* { box-sizing: border-box; }
.teacher-actions { display: flex; flex-wrap: wrap; gap: 8px; }
.teacher-actions:has(button:not([hidden])) { margin-top: 12px; }
.teacher-actions button, #material-visibility { padding: 7px 10px; border: 1px solid #cdd5de; border-radius: 5px; background: #f7f9fb; color: #334356; font-size: 12px; }
#material-visibility { margin-top: 12px; }
#material-hidden { padding: 32px 20px; background: white; border: 1px solid #dde2e8; border-radius: 8px; }
.home { max-width: 640px; margin: 64px auto; padding: 24px; }
.home h1 { margin-bottom: 24px; }
.home h2 { margin-bottom: 20px; }
.home label { display: block; margin-bottom: 8px; }
.home input[type="text"] { max-width: none; }
.home-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 16px; }
.home button, .home a { display: inline-block; padding: 12px 18px; border: 1px solid #cdd5de; border-radius: 6px; background: white; color: #334356; text-decoration: none; }
.home .primary { background: #334f72; color: white; border-color: #334f72; }
.home input[type="email"], .home input[type="password"] { display: block; width: 100%; padding: 10px 12px; border: 1px solid #cdd5de; border-radius: 6px; margin-bottom: 16px; }
.form-note { color: #657080; font-size: 13px; }
.room-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; padding: 16px 0; border-bottom: 1px solid #dce1e8; }
.room-row span { margin-right: auto; font-weight: 600; }
#room-list { margin-bottom: 24px; }
.materials-section { margin-top: 32px; }
#editor-blocks { margin: 24px 0; }
.editor-block h2 { margin-bottom: 16px; }
.editor-block select, .editor-block textarea { display: block; width: 100%; padding: 10px; margin-bottom: 16px; border: 1px solid #cdd5de; border-radius: 6px; font: inherit; }
.editor-block textarea { resize: vertical; }
#choose-material { margin-top: 16px; }
#lesson-select { display: block; width: 100%; padding: 10px; margin-bottom: 12px; border: 1px solid #cdd5de; border-radius: 6px; font: inherit; }
body { margin: 0; background: #f3f4f6; color: #222b36; font: 15px/1.5 system-ui, sans-serif; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; opacity: .45; }
[hidden] { display: none !important; }
:focus-visible { outline: 3px solid #678bbd; outline-offset: 3px; }
.workspace { display: grid; grid-template-columns: minmax(0, 2fr) minmax(0, 1fr); gap: 24px; max-width: 1560px; margin: auto; padding: 32px; align-items: start; }
.lesson-header { padding: 0 0 24px; }
.heading-row, .exercise-heading, .review, .call-heading { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.eyebrow { font-size: 11px; font-weight: 700; letter-spacing: .13em; color: #647080; }
.role-badge { background: #e5eaf0; border-radius: 20px; padding: 4px 12px; font-size: 12px; font-weight: 600; }
h1 { margin: 12px 0 6px; font-size: 30px; line-height: 1.2; letter-spacing: -.03em; }
#lesson-help { margin: 0; color: #657080; font-size: 14px; }
.exercises { display: grid; gap: 16px; }
.exercise { min-width: 0; padding: 24px; border: 1px solid #dde2e8; border-left: 3px solid #dde2e8; border-radius: 10px; background: white; transition: border-color .15s, background .15s; }
.exercise-heading { justify-content: flex-start; margin-bottom: 14px; }
.number { color: #85909e; font-size: 12px; font-weight: 600; font-variant-numeric: tabular-nums; }
h2 { font-size: 16px; line-height: 1.4; margin: 0; font-weight: 600; }
.sentence { display: block; margin-bottom: 12px; font-size: 16px; }
input[type="text"] { display: block; width: 100%; max-width: 420px; border: 1px solid #cdd5de; background: #fafbfc; border-radius: 6px; padding: 10px 12px; color: #222b36; }
input::placeholder { color: #8a94a1; }
input[readonly] { background: #f2f4f7; cursor: default; }
fieldset { border: 0; margin: 0; padding: 0; min-width: 0; }
legend { padding: 0; }
.choices { display: flex; flex-wrap: wrap; gap: 8px; }
.choices label { display: inline-flex; align-items: center; gap: 9px; padding: 9px 14px; border: 1px solid #dce1e8; border-radius: 6px; background: #fafbfc; cursor: pointer; }
.choices label:has(input:checked) { border-color: #8399b7; background: #edf2f8; }
.choices input { accent-color: #486c9a; margin: 0; width: 16px; height: 16px; }
[data-role="teacher"] .choices label { cursor: default; }
[data-role="teacher"] .choices input { opacity: 1; }
.review { border-top: 1px solid #edf0f3; margin-top: 18px; padding-top: 12px; min-height: 34px; }
[data-mark-label] { font-size: 12px; color: #7c8794; }
.mark-buttons { display: flex; gap: 6px; }
.mark-buttons button { width: 34px; height: 30px; border: 1px solid #dce1e8; border-radius: 5px; color: #526071; background: white; font-size: 17px; line-height: 1; }
.exercise[data-mark="correct"] { border-color: #9ec6b2; border-left-color: #438361; background: #f8fcfa; }
.exercise[data-mark="wrong"] { border-color: #dbb0ae; border-left-color: #b35b57; background: #fffafa; }
.exercise[data-mark="correct"] [data-mark-label] { color: #34734f; }
.exercise[data-mark="wrong"] [data-mark-label] { color: #a04b47; }
.mark-buttons [data-mark="correct"][aria-pressed="true"] { background: #e4f1e9; border-color: #7fac91; color: #34734f; }
.mark-buttons [data-mark="wrong"][aria-pressed="true"] { background: #f8e8e7; border-color: #cd9290; color: #a04b47; }
.call-panel { position: sticky; top: 24px; border: 1px solid #dce1e8; border-radius: 10px; background: white; padding: 16px; text-align: center; }
.call-heading { margin-bottom: 14px; }
.call-heading span { font-size: 12px; color: #83909c; }
.videos { position: relative; height: clamp(260px, 42vh, 500px); background: #151a21; border-radius: 7px; overflow: hidden; }
video { background: #151a21; object-fit: contain; }
#remote { width: 100%; height: 100%; }
#local { position: absolute; width: 32%; min-width: 85px; max-width: 160px; aspect-ratio: 16/9; bottom: 10px; right: 10px; border: 1px solid #87929f; border-radius: 5px; transform: scaleX(-1); }
#status { margin: 16px 0 8px; font-size: 14px; }
#hint { color: #657080; margin: 8px 0; font-size: 13px; }
#hint:empty { display: none; }
.controls { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 16px; }
.controls button { padding: 10px 8px; border: 1px solid #dce1e8; border-radius: 6px; background: #f1f4f7; color: #334356; font-size: 12px; }
.controls button[aria-pressed="true"] { background: #f6eddc; border-color: #dfcba4; color: #725225; }
#hangup { grid-column: 1 / -1; background: #a84b4b; border-color: #a84b4b; color: white; }
@media (max-width: 760px) {
  .workspace { grid-template-columns: 1fr; padding: 16px; gap: 20px; }
  .call-panel { position: static; }
  .videos { height: 280px; }
  .exercise { padding: 18px; }
  h1 { font-size: 26px; }
}
.lesson-image,.editor-media {display:block;max-width:100%;max-height:420px;object-fit:contain;margin:12px 0;}
.lesson-video {display:block;width:100%;aspect-ratio:16/9;border:0;margin:12px 0;}
.exercise audio {display:block;max-width:100%;margin:12px 0;}
.matching-row {display:flex;align-items:center;justify-content:space-between;gap:12px;margin:10px 0;}
.matching-row select {max-width:60%;}
.word-order,.word-bank {display:flex;flex-wrap:wrap;gap:8px;min-height:40px;margin:12px 0;}
.word-order {border-bottom:1px solid #cdd5de;padding-bottom:8px;}
.editor-block textarea {width:100%;box-sizing:border-box;}
#block-picker {display:block;margin:12px 0;max-width:100%;}
#block-picker[hidden] {display:none;}

.teacher-nav,.dashboard>.teacher-actions{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin-bottom:20px}.student-latest{display:block;color:#64748b;margin-top:6px;font-weight:normal}#start-form{margin-top:20px}#past-blocks .mark-controls,#past-blocks .teacher-controls{display:none}

#material-list .material-card{border:1px solid #dce1e8;border-radius:6px;padding:16px;margin-bottom:12px;background:white}

.lesson-builder{max-width:960px}
.lesson-builder .builder-modes{display:flex;gap:8px;margin:24px 0;flex-wrap:wrap}
.lesson-builder .builder-modes [aria-pressed="true"]{background:#334f72;color:white;border-color:#334f72}
.lesson-builder .builder-section-heading,.lesson-builder .builder-card-heading{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}
.lesson-builder .builder-section-heading h2,.lesson-builder .builder-card-heading h3{margin:0}
.lesson-builder .builder-block-actions{display:flex;gap:6px;flex-wrap:wrap}
.lesson-builder .builder-block-actions button{padding:6px 10px;font-size:13px}
.lesson-builder .editor-block{margin:16px 0;padding:22px;border:1px solid #dce1e8;border-radius:8px;background:white}
.lesson-builder textarea{display:block;width:100%;padding:10px;font:inherit;border:1px solid #cdd5de;border-radius:5px;margin-bottom:16px;resize:vertical}
.lesson-builder .editor-block input[type="text"]{width:100%;padding:10px;font:inherit;border:1px solid #cdd5de;border-radius:5px;margin-bottom:12px}
.lesson-builder .builder-array{margin-top:20px}
.lesson-builder .builder-array h4{margin-bottom:6px}
.lesson-builder .builder-array-row{display:flex;align-items:end;gap:10px;margin:10px 0}
.lesson-builder .builder-array-row label{flex:1;min-width:0;margin:0}
.lesson-builder .builder-array-row label span{display:block;font-size:13px;margin-bottom:6px}
.lesson-builder .builder-array-row input[type="text"]{margin:0}
.lesson-builder .builder-array-row button{padding:10px;font-size:13px}
.lesson-builder #block-picker{margin-top:20px;padding:20px;background:#f4f6f8;border:1px solid #dce1e8;border-radius:8px}
.lesson-builder .block-types{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:10px;margin-top:16px}
.lesson-builder .block-types button{text-align:left;display:flex;flex-direction:column;gap:7px}
.lesson-builder .block-types span{font-size:13px;color:#657080}
.lesson-builder #save-material{margin-top:24px}
.lesson-builder #preview-panel{margin-top:20px}
.lesson-builder #preview-blocks>.exercise,.lesson-builder #preview-blocks>div{margin-bottom:16px}
@media(max-width:600px){.lesson-builder .builder-array-row{flex-wrap:wrap}.lesson-builder .builder-array-row label{min-width:100px}.lesson-builder .editor-block{padding:14px}}

.lesson-builder .builder-array-row .correct-option{flex:0 0 auto;display:flex;align-items:center;gap:6px;padding:10px 0}
.lesson-builder .correct-option span{margin:0}.gap-sentence input[type="text"]{display:inline-block;width:160px;max-width:100%;margin:0 8px;vertical-align:middle}
.matching-columns{display:grid;grid-template-columns:1fr 1fr;gap:16px}.matching-columns>div{display:flex;flex-direction:column;gap:8px}.matching-item{padding:12px;border:1px solid #cdd5de;border-radius:6px;background:white;text-align:left;color:#334356;overflow-wrap:anywhere}
.matching-item[aria-pressed="true"]{outline:2px solid #5679a2}.matching-item[data-result="correct"]{background:#e4f1e9;border-color:#7fac91}.matching-item[data-result="wrong"]{background:#f8e8e7;border-color:#cd9290}.matching-feedback,.gap-feedback{font-size:14px}
.image-task-thumb{display:block;width:100%;height:110px;object-fit:contain;margin-bottom:8px}.image-task-editor{margin-top:16px}.image-task-item{border:1px solid #dce1e8;border-radius:6px;padding:14px;margin:12px 0}.image-task-editor select{max-width:100%}.image-task-editor .editor-media{max-height:180px}
.sort-columns{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:12px;margin-top:12px}.sort-column{border:1px solid #cdd5de;border-radius:6px;padding:10px;min-height:100px}.sort-column>button{width:100%;padding:10px}.sort-bank{display:flex;flex-wrap:wrap;gap:8px;min-height:40px}.sort-item{padding:10px;margin:4px;border:1px solid #cdd5de;border-radius:5px;background:white;color:#334356}.sort-item[aria-pressed="true"]{outline:2px solid #5679a2}.sort-item[data-result="correct"]{background:#e4f1e9;border-color:#7fac91}.sort-item[data-result="wrong"]{background:#f8e8e7;border-color:#cd9290}.order-text .word-order,.order-text .word-bank{flex-direction:column;align-items:stretch}.order-text button{text-align:left;white-space:normal;overflow-wrap:anywhere}.vocabulary-card{border-bottom:1px solid #dce1e8;padding:14px 0}.vocabulary-card h3{margin:0 0 8px}
/* Calm UI foundation. Opt-in scope protects the lesson and call interfaces. */
.teacher-shell{--ui-bg:#f7f8fa;--ui-surface:#fff;--ui-text:#202b36;--ui-muted:#75808b;--ui-border:#e8ecf0;--ui-accent:#52776b;--ui-accent-soft:#eaf2ee;--ui-radius:18px;--ui-shadow:0 3px 14px #243a4b04;background:var(--ui-bg);color:var(--ui-text);font:15px/1.55 'Segoe UI',system-ui,sans-serif;display:grid;grid-template-columns:238px minmax(0,1fr);min-height:100vh}
.teacher-shell a{color:inherit;text-decoration:none}.teacher-shell button,.teacher-shell input{font:inherit}.teacher-shell button{transition:background .15s,border-color .15s}.teacher-shell :focus-visible{outline:3px solid #91afa3;outline-offset:4px}.teacher-shell h1,.teacher-shell h2,.teacher-shell h3,.teacher-shell p{margin:0}.teacher-shell h1{font-size:36px;line-height:1.2;font-weight:650;letter-spacing:-1px}.teacher-shell h2{font-size:22px;line-height:1.35;letter-spacing:-.4px;font-weight:650}.teacher-shell h3{font-size:17px;font-weight:600;line-height:1.4}.teacher-shell small{font-size:12px;color:var(--ui-muted)}
.shell-sidebar{background:white;border-right:1px solid var(--ui-border);padding:38px 22px 22px;display:flex;flex-direction:column;position:sticky;top:0;height:100vh}.shell-brand{display:flex;align-items:center;font-size:26px;font-weight:700;letter-spacing:-1px;padding:0 10px}.brand-symbol{display:grid;place-items:center;background:var(--ui-accent);color:#fff;border-radius:12px;width:35px;height:35px;margin-right:10px;font-size:25px}.brand-dot{color:var(--ui-accent)}.teacher-shell .nav-caption{font-size:9px;font-weight:650;letter-spacing:1.4px;color:#98a1a8;margin:54px 10px 17px}.shell-sidebar nav{display:grid;gap:7px}.shell-sidebar nav a{padding:12px 14px;display:flex;gap:13px;align-items:center;border-radius:10px;color:#707b84;font-size:14px;font-weight:500}.shell-sidebar nav a>span{font-size:19px;line-height:20px;width:22px;text-align:center}.shell-sidebar nav a:hover{background:#f6f8f7}.shell-sidebar nav a[aria-current]{background:var(--ui-accent-soft);color:#355d4f}.sidebar-bottom{margin-top:auto;border-top:1px solid var(--ui-border);padding-top:22px;display:flex;gap:10px;align-items:center;flex-wrap:wrap}.teacher-avatar{width:34px;height:34px;background:#f0f2f3;border-radius:50%;display:grid;place-items:center;font-size:12px}.sidebar-bottom strong{font-size:12px;font-weight:600}.sidebar-bottom small{display:block;font-size:10px}.sidebar-bottom button{border:0;background:none;color:#79838a;font-size:11px;padding:6px}
.shell-main{min-width:0}.shell-topbar{height:82px;border-bottom:1px solid var(--ui-border);padding:0 48px;display:flex;justify-content:space-between;align-items:center;color:var(--ui-muted);font-size:12px}.quiet-label{font-size:11px}.shell-content{max-width:1280px;margin:auto;padding:48px}.welcome{margin-bottom:44px}.teacher-shell .eyebrow{font-size:10px;letter-spacing:1.7px;color:var(--ui-accent);font-weight:650;margin-bottom:12px}.welcome>p:last-child{margin-top:12px;color:var(--ui-muted);font-size:14px}.section-heading{display:flex;justify-content:space-between;align-items:center;gap:16px;margin-bottom:22px}.section-heading p{color:var(--ui-muted);font-size:13px;margin-top:5px}.ui-button{display:inline-flex;align-items:center;justify-content:center;padding:11px 16px;min-height:42px;border-radius:10px;border:1px solid transparent;font-size:13px;font-weight:600;white-space:nowrap}.teacher-shell .primary{background:var(--ui-accent);color:#fff;border-color:var(--ui-accent)}.teacher-shell .primary:hover{background:#42665a}.teacher-shell .secondary{background:#f6f8f7;color:#385e50;border-color:#e8eeeb}.teacher-shell .secondary:hover{background:var(--ui-accent-soft)}.ui-text-link{font-size:12px;font-weight:600;color:var(--ui-accent)!important}.ui-text-link span{margin-left:8px}
.ui-card{background:var(--ui-surface);border:1px solid var(--ui-border);border-radius:var(--ui-radius);box-shadow:var(--ui-shadow)}.student-grid,.course-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}.teacher-shell #room-list{margin-bottom:0}.teacher-shell .student-card{display:flex;flex-direction:column;align-items:stretch;gap:0;padding:24px}.student-card-head{display:flex;align-items:center;gap:12px}.student-avatar{width:44px;height:44px;flex-shrink:0;border-radius:15px;background:#edf2f0;color:#5d7c70;display:grid;place-items:center;font-size:14px;font-weight:600}.student-card-head small{display:block;margin-top:4px}.student-last{margin:28px 0 24px;flex:1}.student-last small{font-size:9px;letter-spacing:1.1px;font-weight:600}.student-last p{font-size:14px;margin-top:7px!important;overflow-wrap:anywhere}.student-card-actions{display:flex;gap:12px;flex-wrap:wrap;align-items:center}.teacher-shell .copy-invite{padding:5px 0;border:0;background:none;color:var(--ui-muted);font-size:11px}.copy-invite:hover{color:var(--ui-accent)}#recent-courses-section{margin-top:44px}.course-card{padding:24px;display:block;transition:border-color .15s,box-shadow .15s}.course-card:hover{border-color:#b7cdc3;box-shadow:0 5px 18px #243a4b08}.course-symbol{width:40px;height:40px;display:grid;place-items:center;background:#eff3f1;color:#72877d;border-radius:11px;font-size:22px;margin-bottom:20px}.course-card p{font-size:12px;color:var(--ui-muted);margin:7px 0 22px!important}.course-card small{font-size:11px}.ui-empty{grid-column:1/-1;padding:30px;border:1px dashed #dbe4df;border-radius:var(--ui-radius);font-size:14px;color:var(--ui-muted);line-height:1.7}.teacher-shell input[type="text"]{width:100%;max-width:none;padding:11px 14px;border:1px solid #dce4df;border-radius:10px;background:white;color:var(--ui-text)}.student-form{padding:24px;margin-bottom:22px}.student-form label{display:block;font-size:13px;font-weight:600;margin-bottom:10px}.student-form>div{display:flex;gap:12px}.teacher-shell #account-status{font-size:13px;color:var(--ui-accent);margin-top:20px}.shell-footer{border-top:1px solid var(--ui-border);margin-top:48px;padding-top:20px;color:#9aa3aa;font-size:11px}
@media(min-width:1600px){.shell-content{padding-top:60px}}@media(max-width:1200px){.student-grid,.course-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.shell-content{padding:36px}.shell-topbar{padding:0 36px}}@media(max-width:800px){.teacher-shell{display:block}.shell-sidebar{position:static;height:auto;padding:20px;border-right:0;border-bottom:1px solid var(--ui-border)}.shell-brand{font-size:22px}.teacher-shell .nav-caption,.sidebar-bottom .teacher-avatar,.sidebar-bottom div{display:none}.shell-sidebar nav{display:flex;flex-wrap:wrap;margin-top:20px;gap:4px}.shell-sidebar nav a{padding:9px 12px;font-size:12px}.sidebar-bottom{position:absolute;right:20px;top:20px;border:0;padding:0;margin:0}.shell-topbar{display:none}.shell-content{padding:30px 20px}.teacher-shell h1{font-size:30px}.section-heading{align-items:flex-start;flex-wrap:wrap}.student-grid,.course-grid{grid-template-columns:1fr}.student-form>div{flex-direction:column}.welcome{margin-bottom:32px}}
@media(prefers-reduced-motion:reduce){.teacher-shell *{transition:none!important}}
/* Work-first home: a quiet document/list layout, no dashboard panels. */
.work-home{display:block;background:#fbfbfa;--ui-accent:#294c40;--ui-text:#202522;--ui-muted:#788078}.work-home .shell-sidebar{position:static;height:80px;padding:0 6vw;display:flex;flex-direction:row;align-items:center;border:0;border-bottom:1px solid #ededeb;background:#fbfbfa;gap:52px}.work-home .shell-brand{font-size:23px;padding:0}.work-home .brand-symbol{width:29px;height:29px;border-radius:9px;font-size:21px}.work-home .nav-caption,.work-home .sidebar-bottom>span,.work-home .sidebar-bottom>div{display:none}.work-home .shell-sidebar nav{display:flex;gap:24px;margin:0}.work-home .shell-sidebar nav a{padding:28px 0;border-radius:0;font-size:13px;gap:0;color:#858b85;border-bottom:2px solid transparent}.work-home .shell-sidebar nav a svg{display:none}.work-home .shell-sidebar nav a[aria-current]{background:none;border-bottom-color:#294c40;color:#263e32}.work-home .shell-sidebar nav a:hover{background:none;color:#263e32}.work-home .sidebar-bottom{position:static;margin:0 0 0 auto;border:0;padding:0;display:block}.work-home .sidebar-bottom button{font-size:12px}.work-home .shell-content{max-width:1060px;padding:62px 40px 80px}.work-heading{margin-bottom:56px}.work-heading p{font-size:13px;color:#858b85;margin-bottom:14px}.work-home h1{font-size:46px;letter-spacing:-1.7px;font-weight:600}.work-home h2{font-size:14px;font-weight:550;color:#747e75;letter-spacing:0}.work-home .section-heading{margin-bottom:12px;min-height:36px}.work-home #create-room{background:transparent;border:0;padding:8px 0;color:#526157;font-size:12px;min-height:0}.work-home #create-room:hover{color:#172b20}.work-home .student-grid{display:block}.work-home .work-row{display:flex;align-items:center;gap:20px;padding:26px 0;border-bottom:1px solid #e9ece7;flex-wrap:nowrap}.work-home .student-avatar{width:42px;height:42px;border-radius:50%;background:#eef0eb;color:#707d70;font-size:12px}.work-details{flex:1;min-width:0}.work-home .work-details h3{font-size:17px;letter-spacing:-.25px;font-weight:600}.work-home .work-details p{margin-top:5px;font-size:14px;color:#7c837c;overflow-wrap:anywhere}.work-actions{display:flex;align-items:center;gap:26px}.work-home .work-continue{background:#edf1ec;color:#294437;border:0;font-size:12px;min-height:38px;padding:9px 15px;border-radius:9px}.work-home .work-continue:hover{background:#e2e9e0}.work-home .copy-invite{font-size:11px;color:#929a91;white-space:nowrap}.work-home #today-section{margin-bottom:40px}.work-home #today-list .work-continue{background:#294c40;color:#fff}.work-home #today-list .work-continue:hover{background:#1f3c32}.work-home #today-list .work-row:last-child{border-bottom:0}.work-home .ui-empty{background:none;border:0;padding:24px 0;font-size:14px}.work-home .student-form{box-shadow:none;border-radius:10px;margin-top:12px}.work-home #account-status:empty{margin:0}
@media(max-width:800px){.work-home .shell-sidebar{height:auto;min-height:72px;padding:20px 24px;flex-wrap:wrap;gap:20px}.work-home .shell-sidebar nav{order:3;width:100%;justify-content:space-between;gap:14px}.work-home .shell-sidebar nav a{padding:8px 0;font-size:12px}.work-home .shell-content{padding:38px 24px}.work-home h1{font-size:36px}.work-heading{margin-bottom:36px}.work-home .work-row{gap:14px;flex-wrap:wrap;padding:22px 0}.work-details{flex-basis:calc(100% - 60px)}.work-actions{width:100%;padding-left:56px;justify-content:space-between;gap:12px}.work-home .section-heading{flex-wrap:nowrap}.work-home .work-continue{font-size:12px}.work-home .copy-invite{font-size:11px}}
/* Readability pass: same layout, stronger hierarchy. */
.work-home{--ui-text:#171d19;--ui-muted:#626c64}
.work-home h1{font-size:58px;letter-spacing:-1.8px;color:#171d19}
.work-home h2{font-size:18px;font-weight:600;color:#404d43}
.work-home .work-details h3{font-size:21px;font-weight:650;color:#171d19}
.work-home .work-details p{font-size:16px;color:#4f5c52;margin-top:6px}
.work-home .work-heading p{font-size:15px;color:#687269}
.work-home .work-continue{font-size:14px;font-weight:600;min-height:44px;padding:11px 18px;color:#203f2e}
.work-home #today-list .work-continue{color:#fff}
.work-home .copy-invite{font-size:13px;color:#626f64}
.work-home #create-room{font-size:14px;color:#3b5142}
.work-home .shell-sidebar nav a{font-size:14px;color:#626c64}
.work-home .sidebar-bottom button{font-size:13px;color:#626c64}
.work-home .student-avatar{font-size:14px;color:#4f6253}
@media(max-width:800px){.work-home h1{font-size:45px}.work-home h2{font-size:18px}.work-home .work-details h3{font-size:21px}.work-home .work-continue{font-size:14px}.work-home .copy-invite{font-size:13px}.work-home .shell-sidebar nav a{font-size:14px}}
/* Live lesson: equal video participants, readable material, quiet controls. */
.live-lesson{background:#f7f8f6;color:#1d2721;font:16px/1.6 'Segoe UI',system-ui,sans-serif}.live-lesson .workspace{grid-template-columns:minmax(0,1fr) minmax(300px,350px);max-width:1480px;padding:32px 40px;gap:36px}.live-lesson .lesson-header{padding-bottom:28px}.live-lesson .lesson-header>.heading-row{border-bottom:1px solid #e3e8e1;padding-bottom:16px;margin-bottom:18px}.live-lesson .eyebrow{color:#66746a;font-size:12px;letter-spacing:.06em}.live-lesson .role-badge{background:#eaf0e9;color:#385240;font-size:12px;padding:4px 12px}.live-lesson #class-name{font-size:18px;font-weight:600;margin:0 0 16px;color:#273b2d}.live-lesson .lesson-course-title{font-size:14px;font-weight:500;color:#637468;margin:26px 0 8px}.live-lesson #lesson-title{font-size:38px;line-height:1.2;letter-spacing:-1px;margin:12px 0 20px;overflow-wrap:anywhere}.live-lesson #lesson-help{display:none}.live-lesson #class-material{display:flex;flex-wrap:wrap;align-items:center;gap:10px;margin:12px 0}.live-lesson #class-material label{font-size:13px;color:#637468}.live-lesson #class-lesson{flex:1;min-width:140px;max-width:100%;padding:9px 12px;border:1px solid #dce4da;border-radius:8px;background:white;color:#263b2d;font:inherit;font-size:14px}.live-lesson #class-material button,.live-lesson #material-visibility,.live-lesson #history-back{padding:9px 13px;border:1px solid #dce4da;border-radius:8px;background:#fff;color:#334f3c;font-size:13px}.live-lesson #class-history{font-size:13px;margin:14px 0;color:#647166}.live-lesson summary{cursor:pointer;padding:6px 0}.live-lesson #history-list{padding:12px;background:#fff;border-radius:10px;border:1px solid #e0e6de}.live-lesson #material-visibility{margin-top:0}.live-lesson .exercises{gap:22px}.live-lesson .exercise{padding:28px;border:1px solid #e0e6de;border-left-width:3px;border-radius:14px;box-shadow:0 2px 8px #283d3003}.live-lesson .exercise-heading{gap:12px;margin-bottom:20px}.live-lesson .exercise-heading h2{font-size:19px;color:#25392b}.live-lesson .number{display:grid;place-items:center;min-width:32px;height:32px;border-radius:8px;background:#f0f3ee;color:#64755f;font-size:13px}.live-lesson .sentence{font-size:20px;line-height:1.65;margin-bottom:18px}.live-lesson .exercise h3{font-size:20px}.live-lesson input[type="text"]{font-size:18px;padding:12px 14px;border-radius:9px;border-color:#d2dcd0;background:#fdfefd;color:#1c3022}.live-lesson input[readonly]{background:#f6f8f4}.live-lesson .choices{gap:10px}.live-lesson .choices label{font-size:17px;padding:12px 17px;border-radius:9px;background:#fafcf9;border-color:#dce4d8}.live-lesson .choices label:has(input:checked){border-color:#7e9d7e;background:#edf4e9}.live-lesson .choices input{width:18px;height:18px;accent-color:#35583e}.live-lesson [data-mark-label]{font-size:14px}.live-lesson .mark-buttons button{width:40px;height:36px;font-size:20px;border-radius:8px}.live-lesson .teacher-actions{gap:10px}.live-lesson .teacher-actions button{font-size:13px;padding:8px 11px;background:#f6f8f4;border-color:#e4e9df;color:#4b5e4d;border-radius:7px}.live-lesson .exercise[data-mark="correct"]{border-color:#a0bba0;border-left-color:#4c7f4e;background:#fafdf8}.live-lesson .exercise[data-mark="wrong"]{border-color:#d7b3af;border-left-color:#ab655d;background:#fffaf9}.live-lesson .review{margin-top:22px;padding-top:14px}.live-lesson .call-panel{top:24px;padding:0;border:0;border-radius:0;background:none;box-shadow:none;text-align:left}.live-lesson .call-heading{margin:0 0 16px}.live-lesson .call-heading h2{font-size:17px;font-weight:600;color:#445549}.live-lesson .videos{display:flex;flex-direction:column;gap:14px;height:auto;border-radius:0;background:none;overflow:visible}.live-lesson .video-tile{position:relative;margin:0;width:100%;aspect-ratio:16/10;border-radius:13px;background:#202b26;overflow:hidden;border:1px solid #354139}.live-lesson #local,.live-lesson #remote{position:static;display:block;width:100%;height:100%;min-width:0;max-width:none;aspect-ratio:auto;border:0;border-radius:0;background:#202b26;object-fit:contain}.live-lesson .video-tile figcaption{position:absolute;left:12px;bottom:11px;border-radius:6px;background:#16221bcc;color:#fff;padding:4px 9px;font-size:12px;pointer-events:none}.live-lesson[data-viewer-role="teacher"] .local-tile{order:-1}.live-lesson #status{font-size:14px;color:#4c6152;margin:17px 0 8px}.live-lesson #hint{font-size:13px;color:#69766b}.live-lesson .controls{gap:9px;margin-top:14px}.live-lesson .controls button{font-size:13px;min-height:45px;padding:11px 9px;border-radius:9px;background:#fff;border-color:#dbe3d7;color:#2e4836}.live-lesson .controls button[aria-pressed="true"]{background:#f4ecde;border-color:#d9c3a3;color:#725425}.live-lesson #hangup{background:#9c514b;color:white;border-color:#9c514b}.live-lesson :focus-visible{outline:3px solid #90ac90;outline-offset:3px}.live-lesson .matching-item,.live-lesson .sort-item{font-size:17px}.live-lesson .word-bank button,.live-lesson .word-order button{padding:10px 14px;font:inherit;border:1px solid #dbe3d7;border-radius:8px;background:#f8faf6;color:#294031}
@media(max-width:1050px){.live-lesson .workspace{padding:24px;gap:24px;grid-template-columns:minmax(0,1fr) 290px}.live-lesson #lesson-title{font-size:32px}.live-lesson .exercise{padding:22px}}
@media(max-width:760px){.live-lesson .workspace{grid-template-columns:minmax(0,1fr);padding:18px;gap:28px}.live-lesson .call-panel{position:static;max-width:420px;width:100%;margin:auto}.live-lesson .videos{height:auto}.live-lesson #lesson-title{font-size:30px}.live-lesson .sentence{font-size:18px}.live-lesson .exercise{padding:20px}.live-lesson .exercise-heading h2{font-size:18px}.live-lesson .video-tile{aspect-ratio:16/10}}
/* Lesson builder: selected block workspace. */
.builder-screen{background:#f7f8f6;color:#19231d;font-size:16px}
.builder-screen .lesson-builder{max-width:1800px;margin:0 auto;padding:24px 32px 48px}
.builder-screen #editor-fields{min-width:0}
.builder-screen .teacher-nav{margin-bottom:30px}
.builder-screen .builder-header{display:flex;align-items:center;justify-content:space-between;gap:24px}
.builder-screen .builder-header>div{flex:1;min-width:0}
.builder-screen #material-title{font-size:15px;font-weight:600;color:#626c64;margin:0 0 8px}
.builder-screen #lesson-name{font-size:32px;font-weight:650;letter-spacing:-.7px;background:transparent;border:1px solid transparent;padding:8px 0;margin:0;width:100%;box-shadow:none}
.builder-screen #lesson-name:hover,.builder-screen #lesson-name:focus{border-bottom-color:#9baaa0;outline:none}
.builder-screen #save-material{margin:0;flex-shrink:0;background:#294c40;color:white;border-color:#294c40;padding:13px 22px;border-radius:10px}
.builder-screen .builder-details{margin:16px 0 0;max-width:720px}
.builder-screen .builder-details summary{cursor:pointer;color:#46574c;font-size:15px;width:fit-content}
.builder-screen .builder-details>div{padding:16px 0}
.builder-screen #material-status{min-height:22px;margin:10px 0;font-size:15px}
.builder-screen .builder-workspace{display:grid;grid-template-columns:250px minmax(370px,1.2fr) minmax(310px,1fr);gap:24px;align-items:start}
.builder-screen .builder-outline{position:sticky;top:24px;max-height:calc(100vh - 48px);overflow:auto;padding:8px 12px 16px 0}
.builder-screen h2{font-size:21px;line-height:1.3;margin:0}
.builder-screen #block-count{font-size:13px;color:#626c64}
.builder-screen #outline-title{font-size:15px;font-weight:600;line-height:1.5;overflow-wrap:anywhere;margin:18px 0}
.builder-screen .outline-entry{margin:6px 0;border-radius:10px}
.builder-screen .outline-select{display:flex;gap:12px;align-items:baseline;width:100%;text-align:left;border:0;background:transparent;padding:13px 10px;font-size:15px;line-height:1.4;border-radius:10px;color:#26382d}
.builder-screen .outline-select[aria-current=true]{background:#e4ece5;font-weight:650;color:#203f30}
.builder-screen .outline-number{font-variant-numeric:tabular-nums;font-size:13px;color:#626c64}
.builder-screen .outline-actions{display:flex;justify-content:flex-end;gap:4px;padding:3px 6px}
.builder-screen .outline-actions button{padding:3px 11px;border:0;background:transparent;font-size:17px;min-height:30px;color:#46574c}
.builder-screen .outline-actions button:hover{background:#e4ece5}
.builder-screen #add-block{width:100%;margin-top:18px;padding:13px 8px;border:1px dashed #a9b6ab;background:transparent;border-radius:10px;font-size:15px}
.builder-screen .builder-eyebrow{font-size:14px;font-weight:600;color:#56685a;margin:10px 0 16px}
.builder-screen #editor-panel,.builder-screen #preview-panel{min-width:0}
.builder-screen .editor-block{padding:24px;border:1px solid #e1e6df;border-radius:16px;background:white;box-shadow:0 4px 18px #23382a04;margin:0}
.builder-screen .editor-block[hidden]{display:none!important}
.builder-screen .builder-card-heading{display:block}
.builder-screen .builder-card-heading h3{font-size:26px;line-height:1.2;margin:0 0 16px;letter-spacing:-.4px}
.builder-screen .builder-block-actions{justify-content:flex-start;margin-bottom:20px}
.builder-screen .builder-block-actions [data-action=up],.builder-screen .builder-block-actions [data-action=down],.builder-screen .builder-block-actions [data-action=delete]{display:none}
.builder-screen .builder-block-actions button{border:0;background:#f1f4ef;padding:7px 12px;font-size:14px}
.builder-screen label{font-size:15px;font-weight:550;color:#26382d;line-height:1.45}
.builder-screen input:not([type=checkbox]):not([type=radio]),.builder-screen textarea,.builder-screen select{font-size:16px;border-radius:9px;border-color:#ced7cd;padding:11px 12px;max-width:100%;box-sizing:border-box}
.builder-screen textarea{min-height:100px;resize:vertical}
.builder-screen input:focus-visible,.builder-screen textarea:focus-visible,.builder-screen select:focus-visible,.builder-screen button:focus-visible{outline:2px solid #507861;outline-offset:3px}
.builder-screen .form-note{font-size:14px;line-height:1.55;color:#5d6a60}
.builder-screen .builder-array h4{font-size:18px}
.builder-screen .builder-array-row{flex-wrap:wrap;gap:10px;background:#f7f9f5;padding:12px;border-radius:10px;margin:10px 0}
.builder-screen .builder-array-row>label:not(.correct-option){flex:1 1 160px;min-width:0}
.builder-screen .builder-array-row .correct-option{flex:0 1 auto;font-size:14px}
.builder-screen .builder-array-row button{font-size:13px;padding:7px 10px}
.builder-screen #preview-panel{position:sticky;top:24px;background:#eef2eb;border-radius:16px;padding:22px;max-height:calc(100vh - 48px);overflow:auto}
.builder-screen #preview-panel .builder-eyebrow{margin-top:0}
.builder-screen #preview-title{font-size:20px;margin:0 0 24px;line-height:1.4}
.builder-screen #preview-blocks .exercise{background:white;padding:22px;border:1px solid #e1e6df;border-radius:12px;overflow-wrap:anywhere}
.builder-screen #preview-blocks h3{font-size:21px;line-height:1.4}
.builder-screen #preview-blocks .prompt{font-size:19px;line-height:1.6}
.builder-screen #preview-blocks label{font-size:16px}
.builder-screen #preview-blocks img,.builder-screen #preview-blocks iframe,.builder-screen #preview-blocks audio{max-width:100%}
.builder-screen #empty-builder{padding:50px 24px;line-height:1.8;border:1px dashed #bac7b8;border-radius:16px;color:#46574c}
.builder-screen #block-picker{position:fixed;inset:8vh max(24px,calc((100vw - 1040px)/2));z-index:20;overflow:auto;background:#fff;padding:28px;border:1px solid #d6dfd4;border-radius:18px;box-shadow:0 0 0 100vmax #14231b55,0 24px 80px #14231b22}
.builder-screen #block-picker[hidden]{display:none}
.builder-screen #block-picker .builder-section-heading{margin-bottom:24px}
.builder-screen .block-types button{padding:20px;text-align:left;border:1px solid #dde5d9;border-radius:12px;background:#fafcf8;min-height:114px}
.builder-screen .block-types button:hover{background:#edf3e8;border-color:#789570}
.builder-screen .block-types strong{font-size:18px;color:#253a2b}
.builder-screen .block-types span{font-size:14px;line-height:1.5;color:#5d6a60}
.builder-screen .visually-hidden{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%)}
@media(max-width:1150px){.builder-screen .lesson-builder{padding:20px}.builder-screen .builder-workspace{grid-template-columns:200px minmax(0,1fr);gap:20px}.builder-screen #preview-panel{grid-column:2;position:static;max-height:none}.builder-screen .builder-outline{grid-row:1 / span 2}.builder-screen .outline-actions{justify-content:flex-start}}
@media(max-width:680px){.builder-screen .lesson-builder{padding:16px}.builder-screen .builder-header{align-items:stretch;flex-direction:column;gap:12px}.builder-screen #lesson-name{font-size:26px}.builder-screen #save-material{align-self:flex-start}.builder-screen .builder-workspace{display:flex;flex-direction:column}.builder-screen .builder-outline{position:static;width:100%;max-height:320px;box-sizing:border-box}.builder-screen #editor-panel,.builder-screen #preview-panel{width:100%;box-sizing:border-box}.builder-screen .editor-block{padding:20px}.builder-screen #block-picker{inset:16px;padding:20px}.builder-screen .outline-entry{display:flex;align-items:center}.builder-screen .outline-select{flex:1}.builder-screen .outline-actions{flex-shrink:0}}
/* Materials library: course navigation and lesson rows. */
.materials-screen{background:#f7f8f6;color:#19231d;font-size:16px}
.materials-screen .dashboard{max-width:1360px;margin:0 auto;padding:28px 40px 64px}
.materials-screen .teacher-nav{gap:8px;margin-bottom:52px}
.materials-screen .teacher-nav a,.materials-screen #logout{border:0;background:transparent;border-radius:9px;color:#536158;padding:10px 15px}
.materials-screen .teacher-nav [aria-current=page]{background:#e5ece4;color:#244331;font-weight:600}
.materials-screen #logout{margin-left:auto;font-size:14px}
.materials-screen .library-heading{display:flex;align-items:center;justify-content:space-between;gap:24px}
.materials-screen .library-eyebrow{font-size:14px;color:#606d63;margin:0 0 12px}
.materials-screen h1{font-size:46px;letter-spacing:-1.5px;margin:0;line-height:1.15}
.materials-screen .primary{background:#294c40;color:white;border:1px solid #294c40;border-radius:10px;padding:13px 20px;white-space:nowrap}
.materials-screen #account-status{min-height:24px;margin:22px 0;font-size:15px;color:#365842}
.materials-screen .library-layout{display:grid;grid-template-columns:250px minmax(0,1fr);gap:54px;align-items:start}
.materials-screen .library-sidebar{position:sticky;top:24px;min-width:0}
.materials-screen .library-sidebar h2{font-size:18px;margin:0 0 20px}
.materials-screen #course-outline{display:grid;gap:5px;max-height:45vh;overflow:auto}
.materials-screen #course-outline a{display:flex;align-items:baseline;justify-content:space-between;gap:12px;padding:12px;border:0;background:transparent;border-radius:9px;font-size:15px;color:#324c3b;overflow-wrap:anywhere}
.materials-screen #course-outline a:hover{background:#e7eee3}
.materials-screen .course-total{color:#68786b;font-size:13px;font-variant-numeric:tabular-nums}
.materials-screen #new-course{margin-top:24px;border-top:1px solid #dce4d9;padding-top:20px}
.materials-screen #new-course summary{font-size:15px;cursor:pointer;color:#294c40;list-style:none;padding:8px 0}
.materials-screen #course-form{margin-top:18px}
.materials-screen #course-form label{font-size:14px;line-height:1.5;margin-bottom:16px;color:#34473b}
.materials-screen #course-form input,.materials-screen #course-form textarea{margin-top:7px;border:1px solid #cbd7c9;background:white;border-radius:9px;padding:10px 12px;font:inherit;width:100%;resize:vertical}
.materials-screen #course-form button{width:100%;font-size:15px}
.materials-screen .materials-section{margin:0 0 42px;scroll-margin-top:24px}
.materials-screen .course-heading{display:flex;align-items:flex-start;justify-content:space-between;gap:20px;margin-bottom:20px}
.materials-screen .course-heading>div{min-width:0}
.materials-screen .course-heading h2{font-size:27px;line-height:1.3;margin:0 0 8px;letter-spacing:-.5px;overflow-wrap:anywhere}
.materials-screen .course-count{font-size:13px;color:#607263}
.materials-screen .course-heading p{font-size:15px;color:#637066;line-height:1.6;margin:10px 0 0;max-width:650px;white-space:pre-wrap;overflow-wrap:anywhere}
.materials-screen .course-heading>a{font-size:14px;white-space:nowrap;padding:9px 13px;border-color:#d5dfd1;border-radius:9px;background:transparent;color:#36543e}
.materials-screen #material-list .material-card{display:grid;grid-template-columns:minmax(0,1fr) auto auto;gap:12px;align-items:center;border:0;border-bottom:1px solid #e2e8de;border-radius:0;margin:0;padding:22px 24px;background:white}
.materials-screen #material-list .material-card:first-of-type{border-radius:14px 14px 0 0}
.materials-screen #material-list .material-card:last-child{border-radius:0 0 14px 14px;border-bottom:0}
.materials-screen #material-list .material-card:first-of-type:last-child{border-radius:14px}
.materials-screen .material-card>span{font-size:20px;font-weight:600;line-height:1.4;overflow-wrap:anywhere;margin:0}
.materials-screen .material-card .student-latest{font-size:13px;color:#68766b;margin-top:8px;font-weight:400}
.materials-screen .material-card a{border:1px solid #d3dfcf;background:#edf3e9;color:#2a4e35;border-radius:9px;padding:10px 15px;font-size:14px}
.materials-screen .material-card button{border:0;background:transparent;color:#5b6c5f;padding:10px 12px;font-size:14px}
.materials-screen .material-card button:hover{background:#f1f5ee;border-radius:9px}
.materials-screen .course-empty{padding:28px;border:1px dashed #c8d5c3;border-radius:14px;color:#657661;font-size:15px;margin:0}
.materials-screen :focus-visible{outline:2px solid #507861;outline-offset:3px}
@media(max-width:960px){.materials-screen .dashboard{padding:24px}.materials-screen .library-layout{grid-template-columns:200px minmax(0,1fr);gap:28px}.materials-screen #material-list .material-card{grid-template-columns:1fr auto;padding:20px}.materials-screen .material-card>span{grid-column:1 / -1}.materials-screen .material-card a{justify-self:start}.materials-screen .material-card button{justify-self:end}}
@media(max-width:640px){.materials-screen .dashboard{padding:18px}.materials-screen .teacher-nav{gap:2px;margin-bottom:32px}.materials-screen .teacher-nav a,.materials-screen #logout{padding:9px;font-size:14px}.materials-screen h1{font-size:36px}.materials-screen .library-heading{align-items:flex-start;flex-direction:column;gap:20px}.materials-screen .library-layout{display:block}.materials-screen .library-sidebar{position:static;margin-bottom:32px}.materials-screen #course-outline{max-height:210px}.materials-screen #new-course{margin-top:12px}.materials-screen .course-heading h2{font-size:24px}.materials-screen .course-heading{gap:12px}.materials-screen .course-heading>a{font-size:13px;padding:9px}.materials-screen .material-card>span{font-size:19px}}
/* Shared application shell: one header and visual language across teacher pages. */
.app-ui{--ui-bg:#fbfbfa;--ui-text:#171d19;--ui-muted:#626c64;--ui-accent:#294c40;--ui-border:#e4e8e1;background:var(--ui-bg);color:var(--ui-text);font:16px/1.55 'Segoe UI',system-ui,sans-serif}
.app-ui .app-header{height:80px;display:flex;align-items:center;gap:52px;padding:0 40px;border-bottom:1px solid #ededeb;background:var(--ui-bg);width:100%;box-sizing:border-box}
.app-ui .app-brand{display:flex;align-items:center;gap:10px;flex-shrink:0;text-decoration:none;color:#171d19;font-size:23px;font-weight:700;letter-spacing:-1px}
.app-ui .app-symbol{display:grid;place-items:center;width:29px;height:29px;background:var(--ui-accent);color:white;border-radius:9px;font-size:21px}
.app-ui .app-header nav{display:flex;align-items:center;gap:24px;height:100%}
.app-ui .app-header nav a{display:flex;align-items:center;height:100%;border-bottom:2px solid transparent;color:var(--ui-muted);font-size:14px;text-decoration:none;padding:0;background:transparent;border-radius:0;white-space:nowrap}
.app-ui .app-header nav a[aria-current=page]{border-bottom-color:var(--ui-accent);color:#263e32}
.app-ui .app-header nav a:hover{color:#263e32}
.app-ui .app-header #logout{margin:0 0 0 auto;padding:8px 0;border:0;background:transparent;color:var(--ui-muted);font:inherit;font-size:13px}
.app-ui :focus-visible{outline:2px solid #507861;outline-offset:4px}
.app-ui .home{max-width:1060px;margin:0 auto;padding:62px 40px 80px}
.app-ui.builder-screen .lesson-builder{max-width:1800px;padding:40px 32px 64px}
.app-ui.materials-screen .dashboard{max-width:1060px;padding:62px 40px 80px}
.app-ui.materials-screen .library-layout{grid-template-columns:210px minmax(0,1fr);gap:40px}
.app-ui.materials-screen h1,.app-ui.class-screen h1{font-size:58px;font-weight:600;letter-spacing:-1.8px;color:var(--ui-text)}
.app-ui.materials-screen .library-eyebrow{color:var(--ui-muted);font-size:15px;margin-bottom:14px}
.app-ui.materials-screen .course-heading h2{color:var(--ui-text)}
.app-ui .home .primary{background:var(--ui-accent);border-color:var(--ui-accent);color:#fff;border-radius:10px}
.app-ui .home button,.app-ui .home a{font-family:inherit}
.app-ui .home input,.app-ui .home textarea,.app-ui .home select{font-family:inherit}
.app-ui.class-screen .teacher-actions{gap:12px;margin:28px 0 40px}
.app-ui.class-screen .teacher-actions a,.app-ui.class-screen .teacher-actions button{border-radius:9px;font-size:14px}
.app-ui.class-screen .materials-section h2{font-size:24px;margin-bottom:24px}
.app-ui.class-screen #last-lesson{color:var(--ui-muted);font-size:16px}
.app-ui.class-screen #start-form{padding:24px;background:white;border:1px solid var(--ui-border);border-radius:12px}
.app-ui.class-screen #lesson-choice{padding:12px;border:1px solid #cbd7c9;border-radius:9px;width:100%;font-size:16px}
.app-ui.class-screen .room-row{border-color:var(--ui-border);padding:22px 0}
.app-ui.auth-screen .home{max-width:520px;padding-top:64px}
.app-ui.auth-screen h1{font-size:40px;margin:0 0 32px}
.app-ui.auth-screen #auth-form input{border-color:#cbd7c9;border-radius:9px;padding:12px}
.app-ui.auth-screen #auth-submit{width:100%;margin:12px 0}
.app-ui.auth-screen #auth-switch{padding:8px 0;background:transparent;border:0;color:var(--ui-accent)}
@media(max-width:800px){.app-ui .app-header{height:auto;min-height:72px;padding:20px 24px;flex-wrap:wrap;gap:20px}.app-ui .app-header nav{order:3;width:100%;justify-content:space-between;gap:14px}.app-ui .app-header nav a{padding:8px 0;font-size:14px}.app-ui .home,.app-ui.materials-screen .dashboard{padding:38px 24px}.app-ui.materials-screen h1,.app-ui.class-screen h1{font-size:45px}.app-ui.builder-screen .lesson-builder{padding:28px 20px}.app-ui.materials-screen .library-layout{grid-template-columns:180px minmax(0,1fr);gap:24px}}
@media(max-width:640px){.app-ui.materials-screen .library-layout{display:block}.app-ui.materials-screen h1,.app-ui.class-screen h1{font-size:40px}.app-ui .app-header{padding:16px 20px}.app-ui .app-header nav{gap:12px}.app-ui .app-header nav a{font-size:13px}.app-ui .home,.app-ui.materials-screen .dashboard{padding:32px 20px}.app-ui.materials-screen .library-heading{gap:20px}.app-ui.auth-screen h1{font-size:34px}}
/* Exercise interaction and structured editors. */
.drag-source{cursor:grab;touch-action:manipulation}.drag-source:active{cursor:grabbing}.dragging{opacity:.45}.drop-target.drag-over{outline:3px solid #789d80;outline-offset:3px;background:#edf5e8!important}
[data-result=correct]{border-color:#78ab85!important;background:#edf7ef!important}[data-result=wrong]{border-color:#cc938a!important;background:#fff0ed!important}
.matching-item small{display:block;font-size:14px;margin-top:8px}.word-order{min-height:72px;padding:14px;border:1px dashed #a4b8a4;border-radius:10px}.word-bank{min-height:45px}.word-order button,.word-bank button,.sort-item{padding:10px 15px;border:1px solid #cddbc8;border-radius:9px;background:#fff;color:#213b2b;font:inherit}.sort-column{min-height:140px}.sort-bank{min-height:58px}
.image-exercise-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(155px,1fr));gap:16px}.image-answer-card{border:1px solid #dce5d7;border-radius:12px;padding:12px;min-width:0;background:white}.image-answer-card>img{display:block;width:100%;height:150px;object-fit:contain;margin-bottom:12px}.image-answer-card input,.image-answer-card select,.image-word-target{width:100%;max-width:100%;font:inherit;padding:10px;border:1px solid #b9cbb4;border-radius:8px;background:#fafcf8}.image-word-target{min-height:48px}
.multi-gap-text{font-size:19px;line-height:2.8;white-space:pre-wrap}.multi-gap-text input,.multi-gap-text select,.multi-gap-text button{display:inline-block!important;width:auto!important;max-width:200px!important;min-width:95px;padding:7px 12px!important;margin:3px 7px;border:1px solid #b5c8b0;border-radius:8px;background:white;font:inherit;vertical-align:baseline}.statement-card{padding:18px;border:1px solid #dce5d7;border-radius:12px;margin:14px 0}.statement-card>div:first-child{margin-bottom:14px}
.columns-editor,.image-editor-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(190px,1fr));gap:14px}.column-editor-card,.image-editor-card,.statement-editor-card,.gap-editor-card{padding:16px;background:#f5f8f2;border:1px solid #dce5d6;border-radius:12px;margin:12px 0}.column-editor-card>button,.image-editor-card>button{margin-top:10px}.image-editor-card .editor-media{height:130px;width:100%;object-fit:contain}.image-editor-card input[type=file]{font-size:12px!important;padding:5px!important}
.builder-screen .outline-entry{position:relative}.builder-screen .outline-handle{position:absolute;left:-3px;top:10px;padding:3px!important;border:0!important;background:transparent!important;color:#6d806e!important;cursor:grab;font-size:20px}.builder-screen .outline-select{padding-left:23px}
.rich-toolbar{display:flex;gap:4px;flex-wrap:wrap;padding:7px;background:#f2f6ef;border-bottom:1px solid #d4e0cf;border-radius:9px 9px 0 0}.builder-screen .rich-toolbar button{font-size:12px;padding:5px 7px;border:0;background:transparent;border-radius:5px}.rich-editor{border:1px solid #cbd8c5;border-radius:10px;margin:8px 0 18px;background:white}.rich-input{min-height:100px;padding:12px;font-size:16px;outline:none;overflow-wrap:anywhere}.rich-input p{margin:0 0 8px}.rich-input:focus{box-shadow:inset 0 0 0 2px #718e70;border-radius:0 0 9px 9px}.rich-input a,.rich-content a{color:#294c40;text-decoration:underline}.rich-content{overflow-wrap:anywhere}.rich-content p{margin:8px 0}.rich-input ul,.rich-input ol,.rich-content ul,.rich-content ol{padding-left:24px}
@media(max-width:640px){.image-exercise-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.image-answer-card>img{height:110px}.image-answer-card{padding:9px}.columns-editor,.image-editor-grid{grid-template-columns:1fr}}
.exercise textarea{display:block;width:100%;min-height:190px;padding:14px;border:1px solid #cbd7c9;border-radius:9px;font:inherit;resize:vertical;background:white;color:#172b20}.record-status{font-variant-numeric:tabular-nums}.exercise [data-record]{margin:6px 8px 10px 0;padding:10px 14px;border:1px solid #cbd7c9;border-radius:9px;background:#f5f8f2;font:inherit}.exercise [data-record=save]{background:#294c40;color:#fff}.builder-screen .statement-editor-card>button{margin-top:12px}
/* Compact familiar formatting controls, shared by every rich-text field. */
.builder-screen .rich-toolbar{gap:3px;padding:5px 7px;align-items:center}
.builder-screen .rich-toolbar button{display:inline-flex;align-items:center;justify-content:center;width:30px;height:30px;min-width:30px;padding:0;border-radius:5px;color:#354b3d;line-height:1}
.builder-screen .rich-toolbar button:hover{background:#e1eadd;color:#162e20}
.builder-screen .rich-toolbar .format-letter{font-family:Georgia,'Times New Roman',serif;font-size:17px}
.builder-screen .rich-toolbar [data-format=bold] .format-letter{font-weight:800}
.builder-screen .rich-toolbar [data-format=italic] .format-letter{font-style:italic}
.builder-screen .rich-toolbar [data-format=underline] .format-letter{text-decoration:underline;text-underline-offset:3px}
.builder-screen .rich-toolbar [data-format=insertUnorderedList],.builder-screen .rich-toolbar [data-format=createLink]{margin-left:7px}
.builder-screen .rich-toolbar svg{display:block;flex-shrink:0}
/* Compact lesson sections; exercise presentation remains unchanged. */
.lesson-sections{display:grid;gap:12px;margin-bottom:24px;grid-column:1/-1}
.section-pager{display:flex;align-items:center;gap:12px}.section-pager strong{flex:1;overflow-wrap:anywhere}.section-pager span{color:#5c6962;white-space:nowrap}
.lesson-sections button{border:1px solid #d9e2da;border-radius:8px;background:#fff;color:#23382e;padding:8px 12px;cursor:pointer;font:inherit}.lesson-sections button:disabled{opacity:.45;cursor:default}.lesson-sections button:focus-visible{outline:2px solid #294f43;outline-offset:2px}
.section-tabs{display:flex;gap:6px;flex-wrap:wrap}.section-tabs button{padding:7px 12px;font-size:14px}.section-tabs button[aria-current="true"]{background:#294f43;color:#fff}
.outline-section{margin:12px 0;border-bottom:1px solid #e1e7e2;padding-bottom:12px}.outline-section[data-active="true"]{border-bottom-color:#294f43}
.outline-section-header{display:flex;gap:4px;align-items:center}.builder-outline .outline-section-header input{min-width:0;width:100%;padding:8px 4px;font-weight:650;background:transparent;border:1px solid transparent}.builder-outline .outline-section-header input:focus{border-color:#9cac9f}
.outline-section-header button{padding:5px;flex:none}.outline-section-blocks{min-height:44px;padding:4px 0}.outline-section-blocks>button{font-size:12px;padding:4px 10px;margin:4px 0}.outline-section .outline-select{min-width:0}
.outline-section .outline-number{font-size:12px}.exercise[hidden]{display:none!important}
#add-section{margin:8px 0}#preview-panel .section-pager{gap:6px}#preview-panel .section-pager button{padding:6px 10px}
#import-panel{padding:24px;margin:24px 0;background:#fff;border:1px solid #e1e7e2;border-radius:12px}
#import-panel h2{font-size:24px;margin:0 0 20px}#import-panel>label{display:grid;gap:8px;max-width:600px;margin:16px 0}
#import-panel select,#import-panel input[type=file]{padding:10px 12px;border:1px solid #d9e2da;border-radius:8px;background:#fff;font:inherit;max-width:100%;min-width:0}
#import-panel>button{margin:8px 8px 0 0}#import-report ul{max-height:260px;overflow:auto;padding-left:24px}#import-report li{margin:8px 0}

/* Teacher material library */
.library-search{display:block;max-width:560px;margin:24px 0}.library-search input{width:100%;margin-top:8px}
#library-breadcrumb{margin:24px 0}#library-actions{margin:20px 0}.library-group{margin:36px 0}.library-group h2{font-size:26px}
.library-row{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:22px 0;border-bottom:1px solid #e1e7e2}.library-row>div:first-child{min-width:0}.library-row>div:first-child>span{font-size:20px;font-weight:600;overflow-wrap:anywhere}.library-row small{display:block;margin-top:8px;color:#5d6d65}.library-row-actions{display:flex;align-items:center;gap:18px}.library-row details{position:relative}.library-row details[open]{min-width:150px}.library-row details button{display:block;margin-top:8px;width:100%}.library-pager{display:flex;align-items:center;gap:16px;margin:18px 0}.library-module{border-bottom:1px solid #dde5df;padding:20px 0}.library-module>summary{font-size:22px;cursor:pointer}.library-module>.teacher-actions{margin:18px 0}
#library-dialog{border:1px solid #dce5de;border-radius:16px;padding:28px;max-width:540px;width:calc(100% - 40px)}#library-dialog::backdrop{background:#12261c55}#library-fields label{display:block;margin:18px 0}#library-fields input,#library-fields select,#library-fields textarea{display:block;width:100%;margin-top:8px}#library-error{color:#a52e2e}
.account-menu{margin-left:auto;position:relative}.account-menu summary{cursor:pointer;list-style:none;font-weight:600;padding:10px 14px;border-radius:50%;background:#e8eee9}.account-dropdown{position:absolute;right:0;top:45px;z-index:100;background:white;border:1px solid #dde5df;border-radius:12px;padding:18px;min-width:240px;box-shadow:0 8px 30px #152a1e15}.account-dropdown p{overflow-wrap:anywhere}.account-dropdown button{display:block;width:100%;text-align:left;margin-top:8px}.account-info{border:1px solid #dde5df;border-radius:16px;padding:28px;max-width:440px}
@media(max-width:650px){.library-row{align-items:flex-start;gap:12px}.library-row-actions{flex-direction:column;gap:10px}}

.library-search input{font:inherit;font-size:16px;color:#17251f;background:white;border:1px solid #ccd8cf;border-radius:10px;padding:12px 14px;min-height:46px}#library-breadcrumb a{padding:0;border:0;background:none;border-radius:0;min-height:0}#library-breadcrumb{color:#53665b}

/* Material catalog: shared cards on home, course and module pages. */
.materials-screen .home.dashboard{max-width:1320px;width:calc(100% - 64px);margin:0 auto;padding:32px 0 64px}.materials-screen .library-heading{margin:24px 0 20px;align-items:center}.materials-screen .library-heading h1{font-size:44px}.materials-screen #library-breadcrumb{margin:0 0 20px}.materials-screen .library-search{max-width:none;margin:20px 0 28px}.materials-screen #library-actions:empty,.materials-screen #account-status:empty,.materials-screen .library-eyebrow:empty{display:none}
.catalog-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px;margin-top:20px}.catalog-grid:empty,.library-pager:empty{display:none}.catalog-card.library-row{display:flex;flex-direction:column;align-items:stretch;justify-content:flex-start;gap:16px;min-height:220px;padding:24px;border:1px solid #dfe7e1;border-radius:18px;background:#fff;box-shadow:0 3px 12px #1a392705;position:relative}.catalog-card:hover{border-color:#b9cfc1;box-shadow:0 6px 22px #1a39270b}.catalog-symbol{color:#456b5a;font-size:26px;line-height:1;display:block}.catalog-card>div:not(.library-row-actions)>span{display:block;font-size:21px;font-weight:650;line-height:1.35;overflow-wrap:anywhere}.catalog-card small{font-size:13px;color:#637569}.catalog-card p{margin:12px 0}.catalog-card .library-row-actions{display:flex;flex-direction:row;justify-content:space-between;align-items:center;margin-top:auto}.catalog-card .library-row-actions>a{padding:9px 16px;border-radius:9px;background:#edf3ee;border:0;color:#244b3b}.catalog-card .catalog-menu{position:static}.catalog-menu{position:relative}.catalog-menu>summary{cursor:pointer;list-style:none;padding:8px 12px;border-radius:9px;font-size:22px;line-height:1}.catalog-menu>summary::-webkit-details-marker{display:none}.catalog-menu>summary.primary{font-size:16px;line-height:1.4;padding:13px 22px;background:#284e40;color:white}.catalog-menu[open]{z-index:20}.catalog-card .catalog-menu[open]{min-width:0}.catalog-menu>button,.catalog-dropdown{position:relative;background:white}.catalog-menu:not(#create-menu)[open]{background:white;border-radius:10px}.catalog-menu>button{display:block;white-space:nowrap;width:100%;text-align:left;margin:4px 0;padding:8px 12px}.catalog-card .catalog-menu[open]{position:absolute;right:20px;bottom:16px;padding:8px;border:1px solid #dbe5dd;box-shadow:0 8px 24px #17332220}.catalog-dropdown{position:absolute;right:0;top:calc(100% + 8px);width:220px;padding:10px;border:1px solid #dbe5dd;border-radius:12px;box-shadow:0 8px 24px #17332215;z-index:30}.catalog-dropdown a,.catalog-dropdown button{display:block;width:100%;box-sizing:border-box;text-align:left;border:0;background:transparent;padding:12px;font:inherit;color:inherit}.catalog-dropdown a:hover,.catalog-dropdown button:hover{background:#eef4ef}.catalog-modules>.catalog-grid{display:block}.catalog-modules .library-module{padding:20px 0 28px;border:0}.catalog-modules .library-module>summary{font-size:25px;font-weight:600}.catalog-modules .library-module>.teacher-actions{margin:10px 0}.catalog-modules .library-module>.teacher-actions button{font-size:13px;padding:6px 10px}.materials-screen .library-group{margin:32px 0}.materials-screen .library-group h2{font-size:26px;margin-bottom:12px}.materials-screen .library-group>a{display:inline-block;margin-bottom:4px}
@media(min-width:1500px){.catalog-grid{grid-template-columns:repeat(4,minmax(0,1fr))}}
@media(max-width:1000px){.catalog-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.materials-screen .home.dashboard{width:calc(100% - 40px)}}
@media(max-width:600px){.catalog-grid{grid-template-columns:minmax(0,1fr);gap:14px}.materials-screen .home.dashboard{width:calc(100% - 28px);padding-top:20px}.materials-screen .library-heading{align-items:flex-start;gap:16px;flex-wrap:wrap}.materials-screen .library-heading h1{font-size:34px}.catalog-card.library-row{min-height:190px;padding:20px}.materials-screen .app-header{flex-wrap:wrap}.materials-screen .app-header nav{flex-wrap:wrap}}

/* Section outline and full student preview */
.builder-screen #editor-blocks{display:grid;gap:24px}.builder-screen .editor-block{scroll-margin-top:24px}.builder-screen .outline-section[data-active=true]>.outline-section-header{background:#e7efe9;border-radius:9px}.builder-screen .builder-outline{position:sticky;top:20px;max-height:calc(100vh - 40px);overflow:auto}.builder-screen #editor-panel{scroll-margin-top:24px}.preview-section-label{font-weight:600;font-size:16px}
.student-preview-screen{margin:0;background:#f5f7f5;color:#18291f;font-family:Arial,sans-serif}.preview-toolbar{display:flex;justify-content:space-between;align-items:center;gap:16px;padding:16px 28px;background:white;border-bottom:1px solid #dde5df}.preview-toolbar button{margin-left:6px}.preview-toolbar [aria-pressed=true]{background:#294f40;color:white}.student-preview-screen button{font:inherit;cursor:pointer;padding:10px 14px;border:1px solid #d8e2da;border-radius:9px;background:white;color:inherit}.student-preview-screen button:disabled{opacity:.45;cursor:default}
#student-preview-shell{display:grid;grid-template-columns:230px minmax(0,1fr);gap:28px;max-width:1240px;margin:28px auto;padding:0 20px;box-sizing:border-box}#preview-structure{position:sticky;top:20px;max-height:calc(100vh - 40px);overflow:auto;align-self:start}#preview-structure h2{font-size:18px}#preview-structure button{display:block;text-align:left;width:100%;border:0;background:none;margin:4px 0;overflow-wrap:anywhere}#preview-structure [aria-current=true]{background:#e0ece3;font-weight:700}#preview-structure .preview-block-link{padding-left:24px;font-size:14px;color:#526859}#student-preview-page{min-width:0}#student-lesson-title{font-size:32px;overflow-wrap:anywhere}.preview-progress{display:flex;align-items:center;justify-content:space-between;gap:10px;margin:24px 0}.preview-progress>div{min-width:0;overflow-wrap:anywhere}.preview-progress span{display:block;margin-top:8px;color:#596d60}#student-preview-content{display:grid;gap:20px}#student-preview-content .exercise{min-width:0;padding:24px;border:1px solid #dde6df;border-radius:16px;background:white;overflow-wrap:anywhere}#student-preview-content img,#student-preview-content video,#student-preview-content iframe,#student-preview-content audio{max-width:100%}#student-preview-content input:not([type=radio]):not([type=checkbox]),#student-preview-content textarea,#student-preview-content select{max-width:100%;box-sizing:border-box}#student-preview-content textarea{width:100%}#student-preview-content .choices{flex-wrap:wrap}.student-preview-screen[data-device=tablet] #student-preview-shell{max-width:820px;grid-template-columns:170px minmax(0,1fr);gap:16px}.student-preview-screen[data-device=phone] #student-preview-shell{max-width:410px;display:block}.student-preview-screen[data-device=phone] #preview-structure{position:relative;top:0;max-height:180px;border-bottom:1px solid #d8e2da;margin-bottom:20px}.student-preview-screen[data-device=phone] #student-preview-content .exercise{padding:16px}.student-preview-screen[data-device=phone] #student-lesson-title{font-size:26px}
@media(max-width:650px){#student-preview-shell{display:block!important;padding:0 14px}#preview-structure{position:relative;top:0;max-height:180px;margin-bottom:20px}.preview-toolbar{flex-wrap:wrap;padding:12px}#student-preview-content .exercise{padding:16px}.builder-screen .builder-outline{position:sticky;top:0;z-index:3;background:#f5f7f5;max-height:210px}.builder-screen #editor-panel,.builder-screen .editor-block{scroll-margin-top:220px}}

/* Real student lesson: section navigation lives below the participants. */
#student-sections{margin-top:24px;padding-top:18px;border-top:1px solid #dce5df}#student-sections h2{font-size:20px;margin:0 0 12px}#student-sections .section-pager{display:none}#student-sections .lesson-sections{margin:0;padding:0;border:0;background:none}#student-sections .section-list{display:flex;flex-direction:column;gap:6px;max-height:340px;overflow:auto}#student-sections [data-section]{display:block;width:100%;text-align:left;white-space:normal;overflow-wrap:anywhere;padding:10px 12px;border:0;border-radius:9px;background:transparent;font:inherit;color:#354e40}#student-sections [data-section]::before{content:'○';margin-right:9px}#student-sections [data-complete=true]::before{content:'✓'}#student-sections [aria-current=true]{background:#e3eee6;font-weight:650;color:#193f2c}
.multi-gap-text{line-height:1.75;white-space:pre-line}.multi-gap-text p{margin:0 0 .25em;padding:0;line-height:inherit}.multi-gap-text p:last-child{margin-bottom:0}.multi-gap-text input,.multi-gap-text select,.multi-gap-text button{display:inline-block!important;width:var(--gap-width,65px)!important;min-width:40px!important;max-width:140px!important;min-height:0!important;height:30px;box-sizing:border-box;padding:3px 6px!important;margin:0 4px!important;vertical-align:baseline;font-size:inherit;line-height:1.2;white-space:nowrap}.gap-sentence input[type=text]{width:80px;min-width:40px;max-width:140px;padding:3px 6px;margin:0 4px;height:30px;box-sizing:border-box}.multi-gap-text br+br{display:none}
@media(max-width:650px){.multi-gap-text{font-size:17px;line-height:1.85}.multi-gap-text input,.multi-gap-text select,.multi-gap-text button{height:32px}#student-sections .section-list{max-height:240px}}

/* Compact participants and shared live section navigation. */
.live-lesson .workspace{grid-template-columns:minmax(0,1fr) 280px}
.live-lesson .videos{gap:8px}
.live-lesson .video-tile{aspect-ratio:16/8;border-radius:10px}
.live-lesson .video-tile figcaption{left:8px;bottom:7px;padding:2px 7px}
.live-lesson .call-heading{margin-bottom:10px}
.live-lesson #status{margin:10px 0 4px}
.live-lesson #hint:empty{display:none}
.live-lesson .controls{display:flex;gap:8px;margin-top:10px}
.live-lesson .controls button{display:grid;place-items:center;flex:0 0 42px;width:42px;height:42px;min-height:42px;padding:9px}
.live-lesson .controls svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.7;stroke-linecap:round;stroke-linejoin:round}
.live-lesson .controls button[aria-pressed=true]{position:relative}
.live-lesson .controls button[aria-pressed=true]::after{content:'';position:absolute;width:27px;height:2px;transform:rotate(-45deg);background:currentColor}
#call-settings-panel{max-width:320px;padding:22px;border:1px solid #dce5df;border-radius:12px;color:#25392b;background:white;box-shadow:0 12px 40px #0002}
#call-settings-panel::backdrop{background:#0002}
.quick-preview-sections{display:flex;flex-direction:column;gap:4px;max-height:190px;overflow:auto;margin-bottom:12px}
.quick-preview-sections button{text-align:left;padding:8px 10px;border:0;border-radius:7px;background:transparent;color:#354e40;font:inherit}
.quick-preview-sections [aria-current=true]{background:#e3eee6;font-weight:600}
@media(max-width:760px){.live-lesson .workspace{grid-template-columns:minmax(0,1fr)}.live-lesson .call-panel{max-width:420px}.live-lesson .videos{display:grid;grid-template-columns:repeat(2,minmax(0,1fr))}.live-lesson .video-tile{aspect-ratio:4/3}.live-lesson .video-tile figcaption{font-size:11px}}

.live-lesson #lesson-toolbar{display:flex;gap:8px;margin:12px 0}
.live-lesson #lesson-toolbar button{padding:8px 14px;background:white;border:1px solid #dce4da;border-radius:8px;font:inherit;font-size:14px}
.live-lesson dialog{width:min(600px,calc(100vw - 48px));max-height:80vh;box-sizing:border-box;overflow:auto;padding:24px;border:1px solid #dce4da;border-radius:14px;color:#25392b}
.live-lesson dialog::backdrop{background:#17241b55}
.live-lesson dialog h2{margin-top:0;font-size:24px}
.live-lesson #class-history{margin:auto;font-size:15px}
.live-lesson #history-list{padding:0;border:0}
.live-lesson dialog button{padding:8px 12px;border:1px solid #dce4da;border-radius:8px;background:white;color:inherit;cursor:pointer}
.live-lesson [data-student-hidden=true]{display:none!important}
.live-lesson [data-teacher-hidden=true]{border-style:dashed}
.live-lesson [data-teacher-hidden=true] [data-lesson-action=visibility]{background:#e3eee6}
.live-lesson #participants-title{overflow-wrap:anywhere}

.live-lesson .lesson-header>.lesson-course-title{margin-top:0}

.live-lesson .videos[hidden],.live-lesson .controls[hidden]{display:none!important}
.live-lesson #start-call{padding:10px 18px;border:0;border-radius:9px;background:#294f40;color:white;font:inherit}
.live-lesson #class-presence{font-size:13px;color:#647166;margin:8px 0 12px}

.live-lesson .call-panel>#call-settings{width:42px;height:42px;padding:9px;margin-left:8px;border:1px solid #dce4da;border-radius:9px;background:white;vertical-align:middle}.live-lesson .call-panel>#call-settings svg{width:22px;height:22px;fill:none;stroke:currentColor;stroke-width:1.7}

#call-setup{width:min(540px,calc(100vw - 32px))}#call-setup .setup-camera{position:relative;aspect-ratio:16/9;background:#202b26;border-radius:12px;overflow:hidden;margin:14px 0}#setup-preview{width:100%;height:100%;object-fit:contain}#setup-camera-off{position:absolute;inset:0;display:grid;place-items:center;color:white}#setup-camera-off[hidden]{display:none}#call-setup>label{display:block;margin:14px 0 5px;font-weight:600}#call-setup>select{width:100%;box-sizing:border-box;padding:10px;font:inherit;border:1px solid #cdd9d0;border-radius:8px}#setup-level{width:100%;height:18px}#call-setup .setup-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:20px}#call-setup #setup-confirm{background:#294f40;color:white}#call-setup button:disabled{opacity:.5}#setup-error{color:#963c34}

.app-header nav a{font-size:17px;font-weight:550;padding:18px 16px}.app-header nav a[aria-current=page]{font-weight:700;color:#234d3d;border-bottom:3px solid #234d3d;background:#edf3ef}

.live-lesson #empty-material{padding:48px 28px;border:1px solid #dce4da;border-radius:14px;background:white;text-align:center}.live-lesson #empty-material h2{font-size:26px}.live-lesson #empty-material button{padding:12px 20px;border:0;border-radius:9px;background:#294f40;color:white;font:inherit}
.live-lesson #lesson-picker{width:min(1150px,calc(100vw - 32px));max-height:90vh}.picker-top{display:flex;justify-content:space-between;align-items:center;gap:20px}#class-catalog .library-heading,#class-catalog #catalog-top-actions,#class-catalog #library-actions,#class-catalog .catalog-menu,#class-catalog .library-module>.teacher-actions{display:none}#class-catalog .catalog-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}#class-catalog .library-search{display:block}#class-catalog #library-search{width:100%;box-sizing:border-box;padding:12px}#class-catalog .library-row-actions{display:flex;gap:8px;flex-wrap:wrap}.picker-busy #class-catalog{pointer-events:none;opacity:.65}@media(max-width:850px){#class-catalog .catalog-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:550px){#class-catalog .catalog-grid{grid-template-columns:1fr}}

#class-catalog .catalog-modules>.catalog-grid{display:block}#class-catalog .library-group{margin:24px 0}#class-catalog .library-group h2{font-size:24px}

.lesson-embed{display:block;width:100%;max-width:100%;border:0;border-radius:10px;background:#f5f7f5}.lesson-video{max-width:100%;aspect-ratio:16/9}