:root{--brand: #38bdf8;--brand-dark: #0ea5e9;--text: #111827;--text-muted: #6b7280;--border: #e5e7eb;--bg: #ffffff;--bg-subtle: #f9fafb;--radius: 12px;--focus: 3px solid #1d4ed8}*{box-sizing:border-box}html,body,#root{margin:0;height:100%}body{font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;color:var(--text);background:var(--bg);font-size:16px;line-height:1.5}:focus-visible{outline:var(--focus);outline-offset:2px;border-radius:4px}.skip-link{position:absolute;left:-9999px;top:0;z-index:100;background:var(--text);color:#fff;padding:8px 16px;border-radius:0 0 8px}.skip-link:focus{left:0}@media (prefers-reduced-motion: reduce){*{animation:none!important;transition:none!important}}.topbar{display:flex;align-items:center;gap:8px;padding:0 24px;height:64px;border-bottom:1px solid 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a{text-align:left;padding:8px 12px;border:none;background:none;border-radius:8px;cursor:pointer;font-size:14px;color:var(--text);text-decoration:none}.menu__list button:hover,.menu__list a:hover{background:var(--bg-subtle)}main{padding:24px;max-width:1200px;margin:0 auto}.page-title{font-size:34px;font-weight:800;letter-spacing:-1px;margin:8px 0 16px}.row{display:flex;gap:12px;align-items:center;flex-wrap:wrap}.row--between{justify-content:space-between}.tabs{display:flex;gap:20px;border-bottom:1px solid var(--border);margin-bottom:20px;overflow-x:auto}.tabs button,.tabs a{background:none;border:none;padding:10px 2px;font-size:15px;cursor:pointer;color:var(--text);border-bottom:2px solid transparent;white-space:nowrap;text-decoration:none;display:inline-flex;gap:6px;align-items:center}.tabs .active{border-bottom-color:var(--text);font-weight:600}.btn{border:1px solid var(--border);background:var(--bg);color:var(--text);padding:10px 18px;border-radius:999px;font-size:15px;cursor:pointer;font-weight:500}.btn:hover{background:var(--bg-subtle)}.btn--primary{background:var(--brand);border-color:var(--brand);color:#fff}.btn--primary:hover{background:var(--brand-dark)}.btn--small{padding:6px 12px;font-size:13px}.btn--danger{color:#dc2626}.switch{position:relative;display:inline-flex;width:40px;height:22px;margin:0;cursor:pointer}.switch input{position:absolute;opacity:0;width:100%;height:100%;margin:0;cursor:pointer}.switch__slider{flex:1;border-radius:999px;background:var(--border);transition:background .15s}.switch__slider:before{content:"";position:absolute;top:2px;left:2px;width:18px;height:18px;border-radius:50%;background:#fff;transition:transform .15s;box-shadow:0 1px 2px #0000004d}.switch input:checked+.switch__slider{background:var(--brand)}.switch input:checked+.switch__slider:before{transform:translate(18px)}.switch input:focus-visible+.switch__slider{outline:2px solid var(--brand);outline-offset:2px}input[type=text],input[type=email],input[type=url],input[type=number],input[type=date],input[type=password],select,textarea{border:1px solid var(--border);border-radius:8px;padding:10px 12px;font-size:15px;font-family:inherit;background:var(--bg);color:var(--text);min-width:0}textarea{width:100%}label{font-size:14px;font-weight:600;display:block;margin-bottom:4px}.field{margin-bottom:16px}.search{position:relative}.search input{border-radius:999px;padding-left:38px;width:260px;max-width:100%;background:var(--bg-subtle)}.search:before{content:"🔍";position:absolute;left:12px;top:50%;transform:translateY(-50%);font-size:14px}.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:16px;margin:24px 0}.stat__value{font-size:40px;font-weight:700}.stat__label{color:var(--text-muted);display:flex;gap:8px;align-items:center;font-size:15px}.cards{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:20px}.card{border:none;background:none;text-align:left;padding:0;cursor:pointer;font:inherit;color:inherit;position:relative}.card__cover{aspect-ratio:16/10;border-radius:var(--radius);margin-bottom:10px;display:flex;align-items:flex-start;padding:10px;position:relative;overflow:hidden;background-size:cover;background-position:center}.card__badge{background:#fff;border-radius:999px;padding:3px 10px;font-size:12px;font-weight:600}.card__title{font-weight:600;font-size:16px;margin:0 0 4px}.card__meta{color:var(--text-muted);font-size:13px;display:flex;gap:10px;flex-wrap:wrap}.card__fav{position:absolute;top:8px;right:8px;background:#ffffffe6;border:none;border-radius:50%;width:32px;height:32px;cursor:pointer;font-size:15px}.progressbar{height:6px;background:var(--border);border-radius:3px;margin-top:8px;overflow:hidden}.progressbar>div{height:100%;background:var(--brand)}.table-wrap{overflow-x:auto}table{width:100%;border-collapse:collapse;font-size:15px}th{text-align:left;font-size:13px;padding:10px 12px;border-bottom:1px solid var(--border)}td{padding:14px 12px;border-bottom:1px solid var(--border)}tr:hover td{background:var(--bg-subtle)}.panel{border:1px solid var(--border);border-radius:var(--radius);padding:20px;margin-bottom:16px;background:var(--bg)}.panel h3{margin-top:0}.empty{text-align:center;color:var(--text-muted);padding:60px 20px;font-size:17px}.pill{display:inline-block;padding:2px 10px;border-radius:999px;font-size:12px;font-weight:600;background:var(--bg-subtle);border:1px solid var(--border)}.pill--btn{cursor:pointer;font-family:inherit;line-height:inherit;transition:background .12s,border-color .12s}.pill--btn:hover{background:var(--bg);border-color:var(--brand)}.pill--btn:focus-visible{outline:2px solid var(--brand);outline-offset:2px}.learn-grid{display:grid;grid-template-columns:1fr 300px;gap:32px}.sidebar{border-left:1px solid var(--border);padding-left:24px}.sidebar h3{font-size:16px}.sidebar .stat__value{font-size:24px}.player{position:fixed;top:0;right:0;bottom:0;left:0;background:#fff;z-index:50;display:flex;flex-direction:column}.player__bar{display:flex;align-items:center;gap:12px;padding:10px 16px;border-bottom:1px solid var(--border)}.player__frame{flex:1;border:none;width:100%}.player__content{flex:1;overflow:auto;padding:24px;max-width:800px;margin:0 auto;width:100%}.chatbot-fab{position:fixed;right:20px;bottom:20px;z-index:60;width:56px;height:56px;border-radius:50%;border:none;cursor:pointer;background:var(--brand);color:#fff;font-size:24px;box-shadow:0 6px 20px #0003}.chatbot{position:fixed;right:20px;bottom:88px;z-index:60;width:360px;max-width:calc(100vw - 32px);height:480px;max-height:70vh;background:var(--bg);border:1px solid var(--border);border-radius:16px;box-shadow:0 12px 40px #0000002e;display:flex;flex-direction:column;overflow:hidden}.chatbot__head{background:var(--brand);color:#fff;padding:12px 16px;font-weight:600;display:flex;justify-content:space-between;align-items:center}.chatbot__head button{background:none;border:none;color:#fff;font-size:18px;cursor:pointer}.chatbot__log{flex:1;overflow-y:auto;padding:12px;display:flex;flex-direction:column;gap:8px}.msg{max-width:85%;padding:8px 12px;border-radius:14px;font-size:14px;white-space:pre-wrap}.msg--bot{background:var(--bg-subtle);border:1px solid var(--border);align-self:flex-start}.msg--user{background:var(--brand);color:#fff;align-self:flex-end}.msg .courselink{display:block;margin-top:6px;font-weight:600;color:var(--brand-dark)}.chatbot__input{display:flex;gap:8px;padding:10px;border-top:1px solid var(--border)}.chatbot__input input{flex:1}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;z-index:70;background:#11182773;display:grid;place-items:center;padding:16px}.modal{width:420px;max-width:100%;max-height:85vh;overflow:auto;background:var(--bg);border:1px solid var(--border);border-radius:16px;box-shadow:0 12px 40px #00000040;display:flex;flex-direction:column}.modal--wide{width:640px}.modal__head{background:var(--brand);color:#fff;padding:12px 16px;font-weight:600;display:flex;justify-content:space-between;align-items:center;position:sticky;top:0}.modal__head button{background:none;border:none;color:#fff;font-size:18px;cursor:pointer}.modal__body{padding:16px}.editor-block{border:1px solid var(--border);border-radius:10px;padding:12px;margin-bottom:10px}.editor-block__head{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px;color:var(--text-muted);font-size:13px}@media (max-width: 800px){main{padding:16px}.topbar{padding:0 12px;overflow-x:auto}.topbar nav a{padding:8px;font-size:14px}.learn-grid{grid-template-columns:1fr}.sidebar{border-left:none;padding-left:0;border-top:1px solid var(--border);padding-top:16px}.page-title{font-size:26px}.stats{grid-template-columns:repeat(2,1fr)}.search input{width:100%}}