:root{
  --bg:#f3f6fb;
  --surface:#ffffff;
  --surface-2:#f7f9fc;
  --surface-3:#edf2f8;
  --text:#172033;
  --muted:#667085;
  --muted-2:#98a2b3;
  --line:#e4e9f1;
  --line-strong:#d4dce8;
  --brand:#3157d5;
  --brand-2:#5b7cf2;
  --brand-soft:#eef2ff;
  --navy:#101828;
  --green:#16885a;
  --green-soft:#eaf8f1;
  --amber:#b56a00;
  --amber-soft:#fff6e5;
  --red:#c73b49;
  --red-soft:#fff0f1;
  --shadow-sm:0 1px 2px rgba(16,24,40,.05);
  --shadow-md:0 10px 30px rgba(16,24,40,.10);
  --shadow-lg:0 24px 70px rgba(16,24,40,.18);
  --radius-sm:10px;
  --radius:14px;
  --radius-lg:20px;
  --header-h:68px;
  --sidebar-w:292px;
}
*{box-sizing:border-box}
html,body{margin:0;min-height:100%;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;color:var(--text);background:var(--bg)}
body{min-height:100vh;overflow:hidden}
button,input,select,textarea{font:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed;opacity:.55}
input,select,textarea{color:var(--text)}
.hidden{display:none!important}
.mobile-only{display:none!important}
.eyebrow{display:block;font-size:11px;font-weight:800;letter-spacing:.12em;color:var(--brand);margin-bottom:7px}

/* Auth */
.auth-screen{height:100vh;overflow:auto;background:radial-gradient(circle at 12% 20%,rgba(49,87,213,.12),transparent 30%),radial-gradient(circle at 75% 75%,rgba(91,124,242,.10),transparent 26%),#f8fafc;padding:40px}
.auth-shell{max-width:1180px;min-height:calc(100vh - 80px);margin:0 auto;display:grid;grid-template-columns:minmax(0,1.1fr) minmax(380px,460px);grid-template-rows:auto 1fr;gap:40px 80px;align-items:center}
.auth-brand{grid-column:1/-1;display:flex;align-items:center;gap:12px;align-self:start}
.brand-mark{width:44px;height:44px;border-radius:13px;background:linear-gradient(145deg,var(--navy),var(--brand));color:white;display:grid;place-items:center;font-weight:900;box-shadow:0 8px 24px rgba(49,87,213,.22)}
.brand-mark.small{width:38px;height:38px;border-radius:11px;font-size:15px}
.brand-name{font-size:20px;font-weight:850;letter-spacing:-.03em}
.brand-name.compact{font-size:17px}
.brand-tag,.header-context{font-size:12px;color:var(--muted);margin-top:2px}
.auth-copy{max-width:650px;padding:40px 0}
.auth-copy h1{margin:0;max-width:620px;font-size:clamp(42px,5.3vw,72px);line-height:1.02;letter-spacing:-.055em;font-weight:820;color:#131a2b}
.auth-copy>p{max-width:610px;margin:24px 0 0;font-size:18px;line-height:1.7;color:#5d6678}
.auth-feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:38px}
.auth-feature-grid>div{background:rgba(255,255,255,.72);border:1px solid rgba(212,220,232,.8);border-radius:16px;padding:18px;display:flex;flex-direction:column;gap:8px;backdrop-filter:blur(10px)}
.auth-feature-grid b{font-size:12px;color:var(--brand)}
.auth-feature-grid span{font-weight:720;font-size:14px}
.auth-card{background:rgba(255,255,255,.94);border:1px solid rgba(212,220,232,.88);border-radius:26px;padding:30px;box-shadow:var(--shadow-lg);backdrop-filter:blur(12px)}
.auth-card-head h2{margin:0;font-size:28px;letter-spacing:-.03em}.auth-card-head p{margin:8px 0 22px;color:var(--muted)}
.segmented{display:grid;grid-template-columns:1fr 1fr;background:var(--surface-3);border-radius:12px;padding:4px;margin-bottom:22px}
.segmented-btn{border:0;border-radius:9px;background:transparent;color:var(--muted);padding:9px 12px;font-weight:750}.segmented-btn.active{background:white;color:var(--text);box-shadow:var(--shadow-sm)}
.form-field{display:flex;flex-direction:column;gap:7px;margin-bottom:16px}.form-field label{font-size:13px;font-weight:700;color:#344054}
.form-field input,.form-field select,.form-field textarea,.admin-filterbar input,.admin-filterbar select{width:100%;border:1px solid var(--line-strong);background:white;border-radius:11px;padding:11px 12px;outline:none;transition:.16s;box-shadow:0 0 0 0 rgba(49,87,213,0)}
.form-field textarea{min-height:110px;resize:vertical;line-height:1.5}
.form-field input:focus,.form-field select:focus,.form-field textarea:focus,.admin-filterbar input:focus,.admin-filterbar select:focus,.composer textarea:focus{border-color:#92a8f4;box-shadow:0 0 0 3px rgba(49,87,213,.10)}
.password-field{position:relative}.password-field input{padding-right:62px}.icon-text-btn{position:absolute;right:7px;top:50%;transform:translateY(-50%);border:0;background:transparent;color:var(--brand);font-size:12px;font-weight:800;padding:6px}
.form-error{background:var(--red-soft);border:1px solid #f8cfd4;color:#9f2633;border-radius:11px;padding:10px 12px;font-size:13px;margin-bottom:14px}

/* Buttons */
.btn{border:1px solid transparent;border-radius:11px;padding:10px 14px;font-weight:780;transition:.15s;display:inline-flex;align-items:center;justify-content:center;gap:7px;white-space:nowrap}.btn:hover{transform:translateY(-1px)}.btn:active{transform:translateY(0)}
.btn-primary{background:linear-gradient(135deg,var(--brand),var(--brand-2));color:white;box-shadow:0 7px 18px rgba(49,87,213,.20)}
.btn-secondary{background:white;color:#344054;border-color:var(--line-strong);box-shadow:var(--shadow-sm)}
.btn-quiet{background:var(--surface-2);color:#344054;border-color:var(--line)}
.btn-danger{background:var(--red-soft);color:var(--red);border-color:#f7c9cf}
.btn-block{width:100%}
.icon-btn{width:38px;height:38px;border-radius:10px;border:1px solid var(--line);background:white;color:#475467;display:grid;place-items:center;font-size:20px;line-height:1}.icon-btn.subtle{border-color:transparent;background:var(--surface-2)}
.text-btn{border:0;background:transparent;color:var(--brand);font-size:13px;font-weight:800;padding:4px}

/* App shell */
.app{height:100vh;background:var(--bg)}
.app-header{height:var(--header-h);background:rgba(255,255,255,.94);border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 18px;position:relative;z-index:30;backdrop-filter:blur(12px)}
.header-left,.header-actions,.header-brand,.profile-btn{display:flex;align-items:center}.header-left{gap:10px}.header-brand{gap:10px}.header-actions{gap:10px;position:relative}.presence{font-size:12px;color:var(--muted);display:flex;align-items:center;gap:7px;padding:8px 10px}.presence-dot{width:8px;height:8px;background:#22a06b;border-radius:50%;box-shadow:0 0 0 4px #e7f7ef}
.profile-btn{border:1px solid var(--line);background:white;border-radius:12px;padding:6px 9px 6px 6px;gap:8px;color:var(--text)}.profile-avatar{width:32px;height:32px;border-radius:9px;background:var(--brand-soft);color:var(--brand);display:grid;place-items:center;font-size:12px;font-weight:900}.profile-copy{display:flex;flex-direction:column;text-align:left;line-height:1.15}.profile-copy b{font-size:12px}.profile-copy small{color:var(--muted);font-size:10px;margin-top:3px}
.profile-menu{position:absolute;right:0;top:48px;width:230px;background:white;border:1px solid var(--line);border-radius:13px;box-shadow:var(--shadow-md);padding:7px;z-index:50}.profile-menu-copy{padding:10px 10px 12px;border-bottom:1px solid var(--line);display:flex;flex-direction:column;gap:4px}.profile-menu-copy b{font-size:13px}.profile-menu-copy span{font-size:11px;color:var(--muted);overflow:hidden;text-overflow:ellipsis}.profile-menu button{margin-top:6px;width:100%;border:0;background:transparent;text-align:left;border-radius:8px;padding:9px 10px;color:var(--red);font-weight:700}.profile-menu button:hover{background:var(--red-soft)}
.app-body{height:calc(100vh - var(--header-h));display:grid;grid-template-columns:var(--sidebar-w) minmax(0,1fr)}
.library-panel{background:white;border-right:1px solid var(--line);display:flex;flex-direction:column;min-height:0;z-index:20}.library-scroll{overflow:auto;padding:20px 15px 14px;flex:1}.library-title-row{display:flex;align-items:flex-start;justify-content:space-between;margin-bottom:18px}.library-title-row h2{font-size:23px;letter-spacing:-.03em;margin:0}.selector-stack{display:grid;grid-template-columns:1fr 1fr;gap:9px;margin-bottom:18px}.compact-field{margin:0}.compact-field label{font-size:11px}.compact-field select{padding:9px 10px;font-size:13px}.list-section-head{display:flex;align-items:center;justify-content:space-between;color:#475467;font-size:12px;font-weight:800;margin:4px 2px 9px}.count-badge{min-width:24px;height:22px;border-radius:999px;padding:0 8px;background:var(--surface-3);display:grid;place-items:center;font-size:11px;color:var(--muted)}
.lesson-list{display:flex;flex-direction:column;gap:8px}.lesson-card{border:1px solid var(--line);background:white;border-radius:13px;padding:12px;text-align:left;transition:.16s;width:100%}.lesson-card:hover{border-color:#b4c1e9;box-shadow:var(--shadow-sm);transform:translateY(-1px)}.lesson-card.active{border-color:#93a9f4;background:linear-gradient(135deg,#f6f8ff,#fff)}.lesson-card-top{display:flex;gap:10px;align-items:flex-start}.lesson-number{width:30px;height:30px;border-radius:9px;background:var(--surface-3);color:#475467;display:grid;place-items:center;font-weight:850;font-size:11px;flex:0 0 auto}.lesson-card.active .lesson-number{background:var(--brand);color:white}.lesson-card-copy{min-width:0}.lesson-card-copy b{display:block;font-size:13px;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.lesson-card-copy span{display:block;color:var(--muted);font-size:11px;margin-top:4px}.lesson-health{margin-top:10px;display:flex;gap:6px;align-items:center;color:var(--muted);font-size:10px}.lesson-health .dot{width:6px;height:6px;border-radius:50%;background:var(--green)}
.empty-state{display:flex;flex-direction:column;align-items:center;text-align:center;color:var(--muted)}.compact-empty{border:1px dashed var(--line-strong);background:var(--surface-2);border-radius:14px;padding:24px 14px;gap:5px}.empty-icon{width:34px;height:34px;border-radius:11px;background:var(--brand-soft);color:var(--brand);display:grid;place-items:center;font-size:12px;font-weight:900;margin-bottom:5px}.compact-empty b{font-size:12px;color:#344054}.compact-empty span{font-size:11px;line-height:1.5}
.library-footer{border-top:1px solid var(--line);padding:14px 16px;background:#fbfcfe}.progress-mini-copy{display:flex;justify-content:space-between;gap:8px;font-size:10px;color:var(--muted);margin-bottom:7px}.progress-mini-copy span{overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.progress-mini-copy b{color:#344054}.mini-progress{height:6px;background:#e9edf4;border-radius:99px;overflow:hidden}.mini-progress span{display:block;width:0;height:100%;background:linear-gradient(90deg,var(--brand),#7d96ef);transition:width .25s}

/* Student workspace */
.workspace{min-width:0;min-height:0;overflow:auto}.welcome-view{min-height:100%;display:flex;flex-direction:column;justify-content:center;max-width:1060px;margin:0 auto;padding:48px 40px}.welcome-hero{max-width:720px}.welcome-hero h1{font-size:clamp(38px,5vw,64px);line-height:1.03;letter-spacing:-.055em;margin:0}.welcome-hero p{font-size:17px;line-height:1.65;color:var(--muted);max-width:680px;margin:20px 0 26px}.welcome-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:14px;margin-top:50px}.welcome-cards article{background:white;border:1px solid var(--line);border-radius:18px;padding:20px;box-shadow:var(--shadow-sm)}.welcome-cards article>span{display:inline-grid;place-items:center;width:30px;height:30px;background:var(--brand-soft);color:var(--brand);font-size:10px;font-weight:850;border-radius:9px;margin-bottom:16px}.welcome-cards b{display:block;font-size:14px}.welcome-cards p{color:var(--muted);font-size:12px;line-height:1.55;margin:8px 0 0}
.lesson-view{height:100%;min-height:0;display:flex;flex-direction:column;overflow:hidden}.lesson-toolbar{background:white;border-bottom:1px solid var(--line);min-height:82px;padding:14px 18px;display:flex;align-items:center;justify-content:space-between;gap:20px;flex:0 0 auto}.lesson-breadcrumb{color:var(--brand);font-size:10px;font-weight:850;text-transform:uppercase;letter-spacing:.08em}.lesson-toolbar h1{margin:3px 0 0;font-size:21px;letter-spacing:-.025em;white-space:nowrap;max-width:48vw;overflow:hidden;text-overflow:ellipsis}.lesson-toolbar-actions{display:flex;align-items:center;gap:12px}.lesson-progress-wrap{width:190px}.lesson-progress-copy{display:flex;justify-content:space-between;gap:8px;font-size:10px;color:var(--muted);margin-bottom:6px}.lesson-progress-copy b{color:#344054}.lesson-progress{height:6px;border-radius:99px;background:#e9edf4;overflow:hidden}.lesson-progress span{display:block;width:0;height:100%;background:var(--brand);transition:width .25s}
.learning-grid{display:grid;grid-template-columns:minmax(360px,46%) minmax(420px,1fr);flex:1;min-height:0}.material-panel{background:#eef2f7;border-right:1px solid var(--line);display:flex;flex-direction:column;min-height:0}.panel-head{height:54px;padding:0 14px;background:white;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;flex:0 0 auto}.panel-head>div:first-child{display:flex;flex-direction:column;gap:2px}.panel-kicker{font-size:9px;font-weight:850;letter-spacing:.11em;color:var(--muted)}.panel-kicker.light{color:#adb8d0}.panel-head b{font-size:12px}.page-nav{display:flex;align-items:center;gap:8px}.page-nav .icon-btn{width:32px;height:32px;font-size:15px}.page-nav span{font-size:11px;color:var(--muted);min-width:44px;text-align:center}.pdf-wrap{position:relative;flex:1;min-height:220px;margin:12px 12px 8px;background:white;border:1px solid var(--line);border-radius:14px;overflow:hidden;box-shadow:var(--shadow-sm)}.pdf-frame{border:0;width:100%;height:100%;display:block;background:white}.pdf-loading{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;gap:9px;color:var(--muted);font-size:12px;background:white;z-index:2}.spinner{width:17px;height:17px;border-radius:50%;border:2px solid #dce3ee;border-top-color:var(--brand);animation:spin .8s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}.lesson-text-details{background:white;border:1px solid var(--line);border-radius:12px;margin:0 12px 12px;max-height:32%;overflow:auto}.lesson-text-details summary{padding:11px 12px;cursor:pointer;font-size:11px;font-weight:800;color:#475467;position:sticky;top:0;background:white;border-bottom:1px solid transparent}.lesson-text-details[open] summary{border-bottom-color:var(--line)}.part-text{padding:12px;font-size:12px;line-height:1.65;color:#475467;white-space:pre-wrap}
.teacher-panel{min-width:0;min-height:0;display:flex;flex-direction:column;background:white}.teacher-stage{height:160px;background:linear-gradient(135deg,#151d31,#253354);display:grid;grid-template-columns:190px 1fr;overflow:hidden;flex:0 0 auto}.teacher-media{position:relative;display:flex;align-items:flex-end;justify-content:center;overflow:hidden}.teacher-media:after{content:"";position:absolute;left:22px;right:22px;bottom:8px;height:14px;background:rgba(0,0,0,.26);filter:blur(10px);border-radius:50%}.teacher-media video{height:152px;max-width:100%;object-fit:contain;position:relative;z-index:1}.teacher-pulse{position:absolute;left:20px;top:18px;width:9px;height:9px;border-radius:50%;background:#6fe0ad;box-shadow:0 0 0 0 rgba(111,224,173,.5);z-index:3}.teacher-pulse.speaking{animation:pulse 1.3s infinite}@keyframes pulse{70%{box-shadow:0 0 0 10px rgba(111,224,173,0)}100%{box-shadow:0 0 0 0 rgba(111,224,173,0)}}.teacher-stage-copy{padding:22px 20px 18px 4px;color:white;display:flex;flex-direction:column;justify-content:center}.teacher-title-row{display:flex;justify-content:space-between;align-items:flex-start;gap:12px}.teacher-title-row h2{margin:2px 0 0;font-size:23px;letter-spacing:-.03em}.teacher-stage-copy>p{margin:7px 0 13px;color:#c3cce0;font-size:12px}.status-chip{border:1px solid rgba(255,255,255,.18);background:rgba(255,255,255,.09);padding:6px 9px;border-radius:999px;font-size:10px;color:#dbe2f2;white-space:nowrap}.teacher-settings{display:flex;align-items:center;gap:8px}.teacher-settings label{font-size:10px;color:#aeb9d1}.teacher-settings select{border:1px solid rgba(255,255,255,.14);background:rgba(255,255,255,.08);color:white;border-radius:8px;padding:6px 8px;font-size:10px;outline:none}.teacher-settings option{color:var(--text);background:white}.teacher-controls{border-bottom:1px solid var(--line);padding:9px 12px;display:flex;align-items:center;gap:7px;overflow-x:auto;flex:0 0 auto}.teacher-controls .btn{padding:8px 11px;font-size:11px}.chat{flex:1;min-height:0;overflow:auto;padding:16px 18px;display:flex;flex-direction:column;gap:11px;background:linear-gradient(#fff,#fff),radial-gradient(circle at 40% 20%,rgba(49,87,213,.04),transparent 40%)}.message{max-width:min(82%,680px);border-radius:16px;padding:11px 13px;font-size:13px;line-height:1.58;white-space:pre-wrap;box-shadow:var(--shadow-sm)}.message.teacher{align-self:flex-start;background:var(--surface-2);border:1px solid var(--line);border-bottom-left-radius:5px}.message.student{align-self:flex-end;background:linear-gradient(135deg,var(--brand),#5e79d9);color:white;border-bottom-right-radius:5px}.message.system{align-self:center;max-width:90%;background:transparent;color:var(--muted);box-shadow:none;font-size:11px;padding:5px}.message.error{align-self:center;background:var(--red-soft);color:#a42f3b;border:1px solid #f6cbd0}.message-actions{display:flex;gap:6px;margin-top:9px}.message-actions button{border:1px solid var(--line-strong);background:white;color:#475467;border-radius:999px;padding:5px 8px;font-size:10px;font-weight:750}.typing-dots{display:flex;gap:4px;align-items:center;height:18px}.typing-dots span{width:5px;height:5px;border-radius:50%;background:#98a2b3;animation:bounce 1.1s infinite}.typing-dots span:nth-child(2){animation-delay:.15s}.typing-dots span:nth-child(3){animation-delay:.3s}@keyframes bounce{50%{transform:translateY(-4px)}}
.composer{border-top:1px solid var(--line);padding:10px 12px 12px;display:grid;grid-template-columns:1fr auto;gap:8px;flex:0 0 auto}.composer-input-wrap{position:relative}.composer textarea{width:100%;max-height:120px;resize:none;border:1px solid var(--line-strong);border-radius:13px;padding:10px 62px 10px 12px;outline:none;line-height:1.4;font-size:12px}.composer-icon-btn{position:absolute;right:6px;top:6px;bottom:6px;border:0;background:var(--surface-3);color:#475467;border-radius:9px;padding:0 9px;font-size:10px;font-weight:800}.composer-icon-btn.active{background:var(--red-soft);color:var(--red)}.send-btn{border:0;border-radius:12px;background:var(--brand);color:white;font-size:11px;font-weight:850;padding:0 15px}

/* Admin */
.admin-shell{position:fixed;inset:0;background:var(--bg);z-index:80;display:flex;flex-direction:column}.admin-header{height:70px;background:white;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 20px;flex:0 0 auto}.admin-brand{display:flex;align-items:center;gap:11px}.admin-brand>div:last-child{display:flex;flex-direction:column;gap:3px}.admin-brand b{font-size:14px}.admin-brand span{font-size:11px;color:var(--muted)}.admin-body{display:grid;grid-template-columns:245px minmax(0,1fr);flex:1;min-height:0}.admin-nav{background:white;border-right:1px solid var(--line);padding:16px 12px;display:flex;flex-direction:column;gap:5px}.admin-nav-btn{border:0;background:transparent;border-radius:11px;padding:11px 12px;text-align:left;color:#475467;display:flex;flex-direction:column;gap:3px}.admin-nav-btn span{font-size:12px;font-weight:800}.admin-nav-btn small{font-size:10px;color:var(--muted)}.admin-nav-btn.active{background:var(--brand-soft);color:var(--brand)}.admin-nav-btn.active small{color:#687fd4}.admin-content{overflow:auto;padding:28px 30px 60px}.admin-tab{max-width:1280px;margin:0 auto}.admin-page-head{display:flex;align-items:flex-start;justify-content:space-between;gap:20px;margin-bottom:22px}.admin-page-head h1{margin:0;font-size:30px;letter-spacing:-.04em}.admin-page-head p{margin:7px 0 0;color:var(--muted);font-size:13px}.stat-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px;margin-bottom:16px}.stat-card{background:white;border:1px solid var(--line);border-radius:16px;padding:17px;box-shadow:var(--shadow-sm)}.stat-card span{display:block;color:var(--muted);font-size:11px;font-weight:700}.stat-card b{display:block;margin-top:9px;font-size:28px;letter-spacing:-.04em}.stat-card small{display:block;margin-top:5px;color:var(--muted-2);font-size:10px}.admin-two-col{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-bottom:16px}.admin-card{background:white;border:1px solid var(--line);border-radius:16px;padding:17px;box-shadow:var(--shadow-sm);margin-bottom:16px}.card-head{display:flex;align-items:flex-start;justify-content:space-between;gap:12px;margin-bottom:14px}.card-head>div{display:flex;flex-direction:column;gap:4px}.card-head b{font-size:13px}.card-head span{font-size:11px;color:var(--muted);line-height:1.4}.recent-list{display:flex;flex-direction:column}.recent-row{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:10px 0;border-top:1px solid var(--line)}.recent-row:first-child{border-top:0}.recent-main{min-width:0}.recent-main b{font-size:12px;display:block;white-space:nowrap;overflow:hidden;text-overflow:ellipsis}.recent-main span{font-size:10px;color:var(--muted);margin-top:4px;display:block}.recent-meta{font-size:10px;color:var(--muted);white-space:nowrap}.admin-filterbar{display:grid;grid-template-columns:minmax(240px,1fr) 180px 180px;gap:8px;margin-bottom:12px}.admin-filterbar input,.admin-filterbar select{padding:9px 11px;font-size:12px}.admin-table-wrap{background:white;border:1px solid var(--line);border-radius:16px;overflow:hidden;box-shadow:var(--shadow-sm)}.admin-table{width:100%;border-collapse:collapse}.admin-table th{background:#fbfcfe;color:var(--muted);font-size:10px;text-align:left;padding:10px 12px;border-bottom:1px solid var(--line);font-weight:800;text-transform:uppercase;letter-spacing:.05em}.admin-table td{padding:12px;border-bottom:1px solid var(--line);font-size:11px;vertical-align:middle}.admin-table tr:last-child td{border-bottom:0}.table-main{min-width:0}.table-main b{display:block;font-size:12px}.table-main span{display:block;color:var(--muted);font-size:10px;margin-top:3px}.row-actions{display:flex;gap:5px;justify-content:flex-end}.row-actions button{border:1px solid var(--line);background:white;border-radius:8px;padding:6px 8px;font-size:10px;font-weight:750;color:#475467}.row-actions button:hover{background:var(--surface-2)}.row-actions button.danger{color:var(--red)}.status-badge{display:inline-flex;align-items:center;gap:5px;padding:5px 8px;border-radius:999px;font-size:9px;font-weight:800}.status-badge.good{background:var(--green-soft);color:var(--green)}.status-badge.warn{background:var(--amber-soft);color:var(--amber)}.status-badge.bad{background:var(--red-soft);color:var(--red)}.status-badge.neutral{background:var(--surface-3);color:#667085}.status-badge .tiny-dot{width:5px;height:5px;border-radius:50%;background:currentColor}
.ai-grid{align-items:start}.switch-row{display:flex;align-items:flex-start;gap:10px;margin:4px 0 17px;cursor:pointer}.switch-row input{position:absolute;opacity:0}.switch-ui{width:36px;height:20px;border-radius:999px;background:#dfe4ec;position:relative;flex:0 0 auto;margin-top:1px;transition:.15s}.switch-ui:after{content:"";position:absolute;width:16px;height:16px;left:2px;top:2px;background:white;border-radius:50%;box-shadow:0 1px 4px rgba(0,0,0,.16);transition:.15s}.switch-row input:checked+.switch-ui{background:var(--brand)}.switch-row input:checked+.switch-ui:after{transform:translateX(16px)}.switch-row>span:last-child{display:flex;flex-direction:column;gap:4px}.switch-row b{font-size:11px}.switch-row small{font-size:10px;color:var(--muted);line-height:1.45}.system-health{display:grid;gap:9px}.health-row{display:flex;align-items:center;justify-content:space-between;gap:12px;border-top:1px solid var(--line);padding-top:9px;font-size:11px}.health-row:first-child{border-top:0;padding-top:0}.health-row span{color:var(--muted)}.health-warning{background:var(--amber-soft);border:1px solid #f3dfb5;color:#86530a;border-radius:10px;padding:9px 10px;font-size:10px;line-height:1.45}.key-card-head{align-items:center}.square-add-btn{width:40px;height:40px;border:0;border-radius:11px;background:var(--brand);color:white;font-size:24px;line-height:1;box-shadow:0 7px 18px rgba(49,87,213,.2)}.security-note{background:#f8faff;border:1px solid #dfe6ff;border-radius:11px;padding:10px 12px;margin-bottom:12px;display:flex;flex-direction:column;gap:3px}.security-note b{font-size:10px;color:#3049a0}.security-note span{font-size:10px;color:#69769d;line-height:1.45}.key-list{display:flex;flex-direction:column}.key-row{display:grid;grid-template-columns:minmax(180px,1fr) minmax(170px,.8fr) 130px auto;gap:14px;align-items:center;border-top:1px solid var(--line);padding:12px 0}.key-row:first-child{border-top:0}.key-main b{font-size:12px;display:block}.key-main span{font-size:10px;color:var(--muted);margin-top:4px;display:block}.key-mask{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;color:#475467;font-size:11px}.key-state{display:flex;flex-direction:column;gap:4px;align-items:flex-start}.key-state small{font-size:9px;color:var(--muted)}.key-actions{display:flex;gap:5px}.key-actions button{border:1px solid var(--line);background:white;border-radius:8px;padding:6px 8px;font-size:10px;font-weight:750;color:#475467}.key-actions .danger{color:var(--red)}

/* Modal */
.modal-backdrop{position:fixed;inset:0;background:rgba(16,24,40,.45);backdrop-filter:blur(4px);z-index:120;display:grid;place-items:center;padding:20px}.modal{width:min(620px,100%);max-height:min(820px,calc(100vh - 40px));display:flex;flex-direction:column;background:white;border-radius:20px;box-shadow:var(--shadow-lg);overflow:hidden}.modal-head{padding:18px 20px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between}.modal-head h2{margin:0;font-size:22px;letter-spacing:-.03em}.modal-body{padding:20px;overflow:auto}.modal-footer{padding:12px 20px;border-top:1px solid var(--line);display:flex;justify-content:flex-end;gap:8px}.modal-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}.modal-help{font-size:10px;color:var(--muted);line-height:1.5;margin-top:-6px;margin-bottom:14px}.upload-drop{border:1px dashed #b9c5d6;background:var(--surface-2);border-radius:13px;padding:14px}.upload-drop input{width:100%;font-size:11px}.confirm-copy{font-size:13px;line-height:1.6;color:#475467}.confirm-copy b{color:var(--text)}

/* Toast */
.toast-region{position:fixed;right:18px;top:18px;display:flex;flex-direction:column;gap:8px;z-index:200;pointer-events:none}.toast{width:min(360px,calc(100vw - 36px));background:#111827;color:white;border-radius:12px;padding:11px 13px;box-shadow:var(--shadow-lg);font-size:11px;line-height:1.45;animation:toastIn .18s ease-out}.toast.success{background:#116848}.toast.error{background:#9b2e39}.toast.warn{background:#87520b}@keyframes toastIn{from{opacity:0;transform:translateY(-7px)}to{opacity:1;transform:none}}

@media(max-width:1100px){
  :root{--sidebar-w:270px}.learning-grid{grid-template-columns:minmax(320px,43%) minmax(380px,1fr)}.teacher-stage{grid-template-columns:150px 1fr}.teacher-media video{height:145px}.lesson-progress-wrap{display:none}.stat-grid{grid-template-columns:repeat(2,1fr)}.key-row{grid-template-columns:1fr 160px auto}.key-state{display:none}
}
@media(max-width:820px){
  body{overflow:hidden}.desktop-only{display:none!important}.mobile-only{display:grid!important}.app-body{display:block}.library-panel{position:fixed;top:var(--header-h);left:0;bottom:0;width:min(88vw,320px);transform:translateX(-102%);transition:transform .2s ease;box-shadow:var(--shadow-lg);z-index:45}.library-panel.open{transform:translateX(0)}.mobile-scrim{position:fixed;inset:var(--header-h) 0 0;background:rgba(16,24,40,.34);z-index:40;display:block!important}.panel-mobile-head{height:58px;border-bottom:1px solid var(--line);padding:10px 12px;display:flex!important;align-items:center;justify-content:space-between}.panel-mobile-head>div{display:flex;flex-direction:column;gap:2px}.panel-mobile-head b{font-size:13px}.panel-mobile-head span{font-size:10px;color:var(--muted)}.workspace{height:calc(100vh - var(--header-h))}.welcome-view{padding:34px 20px}.welcome-cards{grid-template-columns:1fr;margin-top:30px}.lesson-view{height:100%}.lesson-toolbar{min-height:72px;padding:10px 12px}.lesson-toolbar h1{font-size:17px;max-width:60vw}.lesson-toolbar-actions .btn{padding:8px 10px;font-size:10px}.learning-grid{display:block;overflow:auto}.material-panel{height:58vh;border-right:0;border-bottom:1px solid var(--line)}.teacher-panel{height:72vh}.teacher-stage{height:145px;grid-template-columns:135px 1fr}.teacher-media video{height:135px}.teacher-stage-copy{padding:16px 12px 14px 0}.teacher-title-row h2{font-size:19px}.teacher-stage-copy>p{font-size:10px;margin:5px 0 8px}.teacher-settings label{display:none}.chat{min-height:270px}.message{max-width:92%}.admin-body{display:block}.admin-nav{height:62px;flex-direction:row;overflow-x:auto;border-right:0;border-bottom:1px solid var(--line);padding:8px;position:sticky;top:0;z-index:3}.admin-nav-btn{min-width:120px;padding:8px 10px}.admin-nav-btn small{display:none}.admin-content{padding:20px 14px 50px}.admin-page-head{align-items:center}.admin-page-head h1{font-size:25px}.admin-page-head p{display:none}.admin-two-col{grid-template-columns:1fr}.admin-filterbar{grid-template-columns:1fr 1fr}.admin-filterbar input:first-child{grid-column:1/-1}.admin-table-wrap{overflow-x:auto}.admin-table{min-width:760px}.key-row{grid-template-columns:1fr auto}.key-mask{display:none}.key-actions{justify-content:flex-end}.modal-grid{grid-template-columns:1fr}
}
@media(max-width:560px){
  .auth-screen{padding:18px;overflow:auto}.auth-shell{min-height:auto;display:block}.auth-brand{margin-bottom:46px}.auth-copy{padding:0 0 30px}.auth-copy h1{font-size:38px}.auth-copy>p{font-size:14px;margin-top:16px}.auth-feature-grid{display:none}.auth-card{padding:21px;border-radius:20px}.header-context{display:none}.app-header{padding:0 10px}.header-actions{gap:6px}.header-actions .btn{padding:8px 10px;font-size:10px}.profile-btn{border:0;padding:3px;background:transparent}.lesson-toolbar{align-items:flex-start}.lesson-toolbar-actions{padding-top:4px}.teacher-controls{padding:8px}.teacher-controls .btn{flex:0 0 auto}.teacher-stage{grid-template-columns:115px 1fr}.teacher-media video{height:130px}.teacher-title-row{display:block}.status-chip{display:inline-block;margin-top:5px}.teacher-stage-copy>p{display:none}.admin-header{padding:0 12px}.admin-brand span{display:none}.stat-grid{grid-template-columns:1fr 1fr;gap:8px}.stat-card{padding:14px}.stat-card b{font-size:24px}.admin-page-head{margin-bottom:16px}.admin-page-head .btn{padding:9px 10px;font-size:10px}.admin-filterbar{grid-template-columns:1fr}.admin-filterbar input:first-child{grid-column:auto}.modal-backdrop{padding:10px;align-items:end}.modal{max-height:88vh;border-radius:18px 18px 10px 10px}.toast-region{right:10px;top:10px}
}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;animation:none!important;transition:none!important}}

.mt-16{margin-top:16px!important}