@import "https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&display=swap";:root{--accent:#2f80ed;--accent-soft:color-mix(in srgb, var(--accent) 12%, white);--sidebar:#23272f;--sidebar-hover:#2f3440;--sidebar-text:#aab1bf;--bg:#f1f3f6;--card:#fff;--text:#1d2330;--muted:#6b7385;--line:#e3e6ec;--ok:#27ae60;--ok-soft:#e4f6ec;--bad:#e5484d;--bad-soft:#fdeceb;--warn:#e8a317;--warn-soft:#fdf4e0;--info:#2f80ed;--info-soft:#e7f0fd;--gray-soft:#eef0f3;--radius:10px;--shadow:0 1px 2px #141e320f, 0 1px 8px #141e320a;--shadow-lg:0 10px 40px #141e322e;color:var(--text);background:var(--bg);-webkit-font-smoothing:antialiased;font-family:Inter,Segoe UI,Roboto,Arial,sans-serif;font-size:14px;line-height:1.5}*{box-sizing:border-box}body{background:var(--bg);margin:0}a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}h1,h2,h3,h4{margin:0 0 .5em;line-height:1.25}h1{font-size:24px;font-weight:700}h2{font-size:18px;font-weight:600}h3{font-size:15px;font-weight:600}p{margin:0 0 .75em}button,input,select,textarea{font:inherit;color:inherit}.app{min-height:100vh;display:flex}.sidebar{background:var(--sidebar);width:92px;color:var(--sidebar-text);flex-direction:column;flex-shrink:0;align-items:stretch;height:100vh;display:flex;position:sticky;top:0;overflow-y:auto}.sidebar .logo{color:#fff;letter-spacing:.3px;text-align:center;border-bottom:1px solid #ffffff0f;flex-direction:column;align-items:center;gap:4px;padding:16px 6px 14px;font-size:11px;font-weight:700;display:flex}.sidebar .logo .mark{background:var(--accent);color:#fff;border-radius:10px;place-items:center;width:40px;height:40px;font-size:18px;display:grid}.nav-item{color:var(--sidebar-text);text-align:center;flex-direction:column;align-items:center;gap:5px;padding:12px 4px;font-size:11px;line-height:1.2;display:flex;position:relative}.nav-item:hover{background:var(--sidebar-hover);color:#fff;text-decoration:none}.nav-item.active{color:#fff;background:var(--sidebar-hover)}.nav-item.active:before{content:"";background:var(--accent);border-radius:0 3px 3px 0;width:3px;position:absolute;top:8px;bottom:8px;left:0}.nav-item .count{background:var(--bad);color:#fff;border-radius:10px;min-width:16px;padding:0 5px;font-size:10px;font-weight:600;line-height:16px;position:absolute;top:6px;right:18px}.sidebar .spacer{flex:1}.sidebar .me{border-top:1px solid #ffffff0f;padding:12px 6px}.main{flex-direction:column;flex:1;min-width:0;display:flex}.topbar{background:var(--card);border-bottom:1px solid var(--line);z-index:5;align-items:center;gap:16px;height:56px;padding:0 24px;display:flex;position:sticky;top:0}.topbar .crumbs{color:var(--muted);white-space:nowrap;text-overflow:ellipsis;flex:1;min-width:0;font-size:13px;overflow:hidden}.topbar .crumbs a{color:var(--muted)}.topbar .crumbs b{color:var(--text);font-weight:600}.content{width:100%;padding:24px}.page-head{flex-wrap:wrap;align-items:flex-start;gap:16px;margin-bottom:20px;display:flex}.page-head .grow{flex:1;min-width:240px}.page-head .sub{color:var(--muted);margin:0}.card{background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);border:1px solid var(--line)}.card.pad{padding:20px}.card+.card{margin-top:16px}.card-title{border-bottom:1px solid var(--line);align-items:center;gap:8px;padding:14px 20px;font-weight:600;display:flex}.card-title .grow{flex:1}.btn{border:1px solid var(--line);cursor:pointer;white-space:nowrap;background:#fff;border-radius:8px;justify-content:center;align-items:center;gap:6px;height:36px;padding:0 14px;font-weight:500;transition:background .15s,border-color .15s,opacity .15s;display:inline-flex}.btn:hover{background:#f6f7f9;text-decoration:none}.btn:disabled{opacity:.5;cursor:not-allowed}.btn.primary{background:var(--accent);border-color:var(--accent);color:#fff}.btn.primary:hover{filter:brightness(.95)}.btn.success{background:var(--ok);border-color:var(--ok);color:#fff}.btn.danger{color:var(--bad);background:#fff;border-color:#f3c3c3}.btn.danger.solid{background:var(--bad);border-color:var(--bad);color:#fff}.btn.ghost{background:0 0;border-color:#0000}.btn.ghost:hover{background:var(--gray-soft)}.btn.sm{height:30px;padding:0 10px;font-size:13px}.btn.lg{height:44px;padding:0 22px;font-size:15px}.btn.icon{width:36px;padding:0}.btn.sm.icon{width:30px}.field{flex-direction:column;gap:6px;margin-bottom:14px;display:flex}.field>label,.label{color:var(--muted);font-size:13px;font-weight:500}.field .hint{color:var(--muted);font-size:12px}.input,.select,.textarea{border:1px solid var(--line);background:#fff;border-radius:8px;outline:none;width:100%;height:38px;padding:0 12px;transition:border-color .15s,box-shadow .15s}.textarea{resize:vertical;height:auto;min-height:90px;padding:10px 12px}.input:focus,.select:focus,.textarea:focus{border-color:var(--accent);box-shadow:0 0 0 3px var(--accent-soft)}.row{flex-wrap:wrap;align-items:center;gap:12px;display:flex}.row.top{align-items:flex-start}.grow{flex:1}.grid2{grid-template-columns:1fr 1fr;gap:0 16px;display:grid}.grid3{grid-template-columns:repeat(3,1fr);gap:0 16px;display:grid}.check{cursor:pointer;-webkit-user-select:none;user-select:none;align-items:center;gap:8px;display:inline-flex}.check input{width:16px;height:16px;accent-color:var(--accent)}.muted{color:var(--muted)}.small{font-size:12px}.nowrap{white-space:nowrap}.mt{margin-top:16px}.mb{margin-bottom:16px}.divider{background:var(--line);height:1px;margin:16px 0}.badge{white-space:nowrap;border-radius:20px;align-items:center;gap:5px;padding:2px 9px;font-size:12px;font-weight:500;line-height:18px;display:inline-flex}.badge .dot{background:currentColor;border-radius:50%;width:6px;height:6px}.badge.gray{background:var(--gray-soft);color:#5b6477}.badge.info{background:var(--info-soft);color:#1f63c6}.badge.warn{background:var(--warn-soft);color:#a86f00}.badge.ok{background:var(--ok-soft);color:#1e8a4c}.badge.okSolid{background:var(--ok);color:#fff}.badge.bad{background:var(--bad-soft);color:#c4353a}.badge.orange{color:#c25a00;background:#fff0e4}.progress{background:var(--gray-soft);border-radius:6px;height:6px;overflow:hidden}.progress>div{background:var(--accent);border-radius:6px;height:100%;transition:width .3s}.progress.ok>div{background:var(--ok)}.table{border-collapse:collapse;width:100%}.table th{text-align:left;color:var(--muted);text-transform:uppercase;letter-spacing:.3px;border-bottom:1px solid var(--line);background:#fafbfc;padding:10px 16px;font-size:12px;font-weight:500}.table td{border-bottom:1px solid var(--line);vertical-align:middle;padding:12px 16px}.table tr:last-child td{border-bottom:none}.table tr.click{cursor:pointer}.table tr.click:hover td{background:#f8f9fb}.tabs{border-bottom:1px solid var(--line);flex-wrap:wrap;gap:4px;margin-bottom:16px;display:flex}.tab{cursor:pointer;color:var(--muted);background:0 0;border:0;border-bottom:2px solid #0000;margin-bottom:-1px;padding:10px 14px;font-weight:500}.tab:hover{color:var(--text)}.tab.active{color:var(--accent);border-bottom-color:var(--accent)}.tab .n{background:var(--gray-soft);color:var(--muted);border-radius:10px;margin-left:4px;padding:0 7px;font-size:12px}.tab.active .n{background:var(--accent-soft);color:var(--accent)}.avatar{color:#fff;border-radius:50%;flex-shrink:0;place-items:center;width:34px;height:34px;font-size:13px;font-weight:600;display:inline-grid}.avatar.lg{width:56px;height:56px;font-size:20px}.person{align-items:center;gap:10px;min-width:0;display:flex}.person .nm{font-weight:500}.person .em{color:var(--muted);font-size:12px}.empty{text-align:center;color:var(--muted);padding:48px 20px}.empty svg{color:#c3c8d2;margin-bottom:8px}.alert{border-radius:8px;align-items:flex-start;gap:10px;margin-bottom:16px;padding:12px 16px;display:flex}.alert.warn{background:var(--warn-soft);color:#7a5200}.alert.bad{background:var(--bad-soft);color:#9b2a2e}.alert.info{background:var(--info-soft);color:#1b4f9c}.alert.ok{background:var(--ok-soft);color:#176b3b}.alert svg{flex-shrink:0;margin-top:2px}.alert .t{margin-bottom:2px;font-weight:600}.overlay{z-index:50;background:#12161e73;place-items:center;padding:20px;display:grid;position:fixed;inset:0}.modal{width:100%;max-width:520px;box-shadow:var(--shadow-lg);background:#fff;border-radius:12px;flex-direction:column;max-height:calc(100vh - 40px);display:flex}.modal.wide{max-width:760px}.modal-head{border-bottom:1px solid var(--line);align-items:center;padding:18px 20px;display:flex}.modal-head h2{flex:1;margin:0}.modal-body{padding:20px;overflow-y:auto}.modal-foot{border-top:1px solid var(--line);justify-content:flex-end;gap:8px;padding:14px 20px;display:flex}.toasts{z-index:100;flex-direction:column;align-items:center;gap:8px;display:flex;position:fixed;bottom:20px;left:50%;transform:translate(-50%)}.toast{color:#fff;box-shadow:var(--shadow-lg);white-space:pre-line;background:#23272f;border-radius:8px;max-width:520px;padding:10px 16px;animation:.2s ease-out pop}.toast.error{background:var(--bad)}@keyframes pop{0%{opacity:0;transform:translateY(8px)}}.cards{grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:20px;display:grid}.tcard{border-radius:var(--radius);box-shadow:var(--shadow);border:1px solid var(--line);color:inherit;background:#fff;flex-direction:column;transition:transform .15s,box-shadow .15s;display:flex;overflow:hidden}.tcard:hover{text-decoration:none;transform:translateY(-2px);box-shadow:0 6px 20px #141e321a}.tcard .cover{color:#fff;align-items:flex-end;height:132px;padding:14px;display:flex;position:relative}.tcard .cover .kind{text-transform:uppercase;letter-spacing:.6px;background:#00000038;border-radius:10px;padding:2px 8px;font-size:11px;position:absolute;top:12px;left:14px}.tcard .cover .ico{opacity:.35;position:absolute;top:14px;right:14px}.tcard .cover h3{text-shadow:0 1px 2px #0003;margin:0;font-size:17px}.tcard .body{flex-direction:column;flex:1;gap:10px;padding:14px 16px 16px;display:flex}.tcard .meta{color:var(--muted);flex-wrap:wrap;align-items:center;gap:8px;font-size:12px;display:flex}.lessons{margin:0;padding:0;list-style:none}.lesson-row{border-bottom:1px solid var(--line);color:inherit;align-items:center;gap:16px;padding:14px 20px;display:flex}.lesson-row:last-child{border-bottom:none}a.lesson-row:hover{background:#f8f9fb;text-decoration:none}.lesson-row .num{background:var(--gray-soft);width:34px;height:34px;color:var(--muted);border-radius:50%;flex-shrink:0;place-items:center;font-weight:600;display:grid}.lesson-row .num.done{background:var(--ok);color:#fff}.lesson-row .num.locked{color:#b3b9c5;background:#f3f4f6}.lesson-row .num.test{background:var(--accent);color:#fff}.lesson-row .info{flex:1;min-width:0}.lesson-row .info .t{font-weight:500}.lesson-row .info .d{color:var(--muted);font-size:12px}.lesson-row.locked{opacity:.65}.lesson-row.important{border-left:3px solid var(--bad)}.lesson-content{font-size:15px;line-height:1.65}.lesson-content h2{margin-top:1.2em;font-size:20px}.lesson-content h2:first-child{margin-top:0}.lesson-content h3{margin-top:1.1em;font-size:16px}.lesson-content ul,.lesson-content ol{margin:0 0 .8em;padding-left:22px}.lesson-content li{margin-bottom:4px}.lesson-content blockquote{background:var(--info-soft);border-left:3px solid var(--accent);border-radius:0 8px 8px 0;margin:1em 0;padding:12px 16px}.lesson-content img{border-radius:8px;max-width:100%}.block+.block{margin-top:20px}.file-block{border:1px solid var(--line);background:#fafbfc;border-radius:10px;align-items:center;gap:14px;padding:14px 16px;display:flex}.file-block .ext{color:#fff;border-radius:6px;flex-shrink:0;place-items:center;width:44px;height:52px;font-size:11px;font-weight:700;display:grid}.doc-frame{border:1px solid var(--line);background:#fff;border-radius:10px;width:100%;height:560px;margin-top:10px}.video-wrap{aspect-ratio:16/9;background:#000;border-radius:10px;position:relative;overflow:hidden}.video-wrap video,.video-wrap iframe{border:0;width:100%;height:100%;position:absolute;inset:0}.q-card{padding:28px}.q-card .q-text{margin-bottom:20px;font-size:18px;font-weight:600}.opt{border:1.5px solid var(--line);cursor:pointer;border-radius:10px;align-items:center;gap:12px;margin-bottom:10px;padding:12px 16px;transition:border-color .15s,background .15s;display:flex}.opt:hover{border-color:#c9d3e3}.opt.sel{border-color:var(--accent);background:var(--accent-soft)}.opt input{width:18px;height:18px;accent-color:var(--accent)}.opt.right{border-color:var(--ok);background:var(--ok-soft)}.opt.wrong{border-color:var(--bad);background:var(--bad-soft)}.q-nav{flex-wrap:wrap;gap:6px;display:flex}.q-nav button{border:1px solid var(--line);cursor:pointer;background:#fff;border-radius:8px;width:34px;height:34px;font-weight:500}.q-nav button.answered{background:var(--accent-soft);border-color:var(--accent);color:var(--accent)}.q-nav button.cur{background:var(--accent);color:#fff;border-color:var(--accent)}.timer{font-variant-numeric:tabular-nums;align-items:center;gap:6px;font-weight:600;display:inline-flex}.timer.low{color:var(--bad)}.score-ring{border-radius:50%;flex-shrink:0;place-items:center;width:128px;height:128px;display:grid;position:relative}.score-ring .inner{text-align:center;background:#fff;border-radius:50%;place-items:center;width:104px;height:104px;display:grid}.score-ring .pct{font-size:28px;font-weight:700;line-height:1}.stats{grid-template-columns:repeat(auto-fit,minmax(165px,1fr));gap:16px;margin-bottom:20px;display:grid}.stat{color:inherit;flex-direction:column;gap:4px;padding:16px 18px;display:flex}a.stat:hover{text-decoration:none;box-shadow:0 4px 14px #141e3214}.stat .v{font-size:28px;font-weight:700;line-height:1.1}.stat .l{color:var(--muted);align-items:center;gap:6px;font-size:13px;display:flex}.timeline{margin:0;padding:0;list-style:none}.timeline li{padding:0 0 14px 20px;font-size:13px;position:relative}.timeline li:before{content:"";background:var(--accent);border-radius:50%;width:7px;height:7px;position:absolute;top:7px;left:4px}.timeline li:after{content:"";background:var(--line);width:1px;position:absolute;top:16px;bottom:0;left:7px}.timeline li:last-child:after{display:none}.timeline .when{color:var(--muted);font-size:12px}.editor-shell{grid-template-columns:280px 1fr;align-items:start;gap:20px;display:grid}.lesson-nav .item{cursor:pointer;border-radius:8px;align-items:center;gap:8px;padding:10px 12px;display:flex}.lesson-nav .item:hover{background:var(--gray-soft)}.lesson-nav .item.active{background:var(--accent-soft);color:var(--accent);font-weight:500}.lesson-nav .item .t{text-overflow:ellipsis;white-space:nowrap;flex:1;min-width:0;overflow:hidden}.block-edit{border:1px solid var(--line);background:#fff;border-radius:10px;margin-bottom:14px}.block-edit .bh{border-bottom:1px solid var(--line);color:var(--muted);background:#fafbfc;border-radius:10px 10px 0 0;align-items:center;gap:8px;padding:8px 12px;font-size:12px;font-weight:500;display:flex}.block-edit .bb{padding:12px}.rte-toolbar{border-bottom:1px solid var(--line);flex-wrap:wrap;gap:2px;padding:4px;display:flex}.rte-toolbar button{cursor:pointer;color:#4a5263;background:0 0;border:0;border-radius:6px;place-items:center;width:30px;height:30px;display:grid}.rte-toolbar button:hover{background:var(--gray-soft)}.rte{outline:none;min-height:160px;padding:12px 14px}.rte:empty:before{content:attr(data-placeholder);color:#a4abb8}.dropzone{border:2px dashed var(--line);text-align:center;color:var(--muted);cursor:pointer;border-radius:10px;padding:24px;transition:border-color .15s,background .15s}.dropzone:hover,.dropzone.over{border-color:var(--accent);background:var(--accent-soft)}.add-blocks{border:1px dashed var(--line);border-radius:10px;flex-wrap:wrap;justify-content:center;gap:8px;padding:14px;display:flex}.q-edit{border:1px solid var(--line);background:#fff;border-radius:10px;margin-bottom:14px}.q-edit .qh{border-bottom:1px solid var(--line);background:#fafbfc;border-radius:10px 10px 0 0;align-items:center;gap:10px;padding:10px 14px;display:flex}.q-edit .qn{font-weight:600}.q-edit .qb{padding:14px}.opt-edit{align-items:center;gap:8px;margin-bottom:8px;display:flex}.mail{grid-template-columns:360px 1fr;min-height:calc(100vh - 104px);display:grid}.mail-list{border-right:1px solid var(--line);max-height:calc(100vh - 150px);overflow-y:auto}.mail-item{border-bottom:1px solid var(--line);cursor:pointer;padding:12px 16px}.mail-item:hover{background:#f8f9fb}.mail-item.active{background:var(--accent-soft)}.mail-item.unread .s{font-weight:700}.mail-item .s{white-space:nowrap;text-overflow:ellipsis;overflow:hidden}.mail-view{padding:24px 32px}.mail-body{white-space:pre-line;line-height:1.7}.mail-letter{border:1px solid var(--line);border-radius:12px;max-width:600px;overflow:hidden}.mail-letter .lh{background:var(--sidebar);color:#fff;align-items:center;gap:10px;padding:16px 24px;font-weight:700;display:flex}.mail-letter .lb{padding:24px}.login-wrap{grid-template-columns:1.1fr 1fr;min-height:100vh;display:grid}.login-side{background:var(--sidebar);color:#fff;background-image:radial-gradient(circle at 20% 20%, color-mix(in srgb, var(--accent) 45%, transparent), transparent 55%), radial-gradient(circle at 80% 90%, #38ef7d2e, transparent 50%);flex-direction:column;justify-content:space-between;padding:48px;display:flex}.login-side h1{margin-bottom:12px;font-size:36px}.login-side .feat{color:#d4d9e3;align-items:flex-start;gap:12px;margin-bottom:18px;display:flex}.login-side .feat svg{color:#fff;background:#ffffff1a;border-radius:8px;flex-shrink:0;width:34px;height:34px;padding:6px}.login-form{background:#fff;place-items:center;padding:40px;display:grid}.login-form .box{width:100%;max-width:380px}.code-input{letter-spacing:10px;text-align:center;height:52px;font-size:22px;font-weight:600}.demo-fab{z-index:40;position:fixed;bottom:20px;right:20px}.demo-fab>button{height:42px;box-shadow:var(--shadow-lg);color:#fff;cursor:pointer;background:#23272f;border:0;border-radius:24px;align-items:center;gap:8px;padding:0 16px;font-weight:500;display:inline-flex}.demo-panel{width:320px;box-shadow:var(--shadow-lg);border:1px solid var(--line);background:#fff;border-radius:12px;position:absolute;bottom:52px;right:0;overflow:hidden}.demo-panel .dh{border-bottom:1px solid var(--line);color:var(--muted);background:#fafbfc;padding:12px 16px;font-size:12px}.demo-panel .du{cursor:pointer;align-items:center;gap:10px;padding:8px 16px;display:flex}.demo-panel .du:hover{background:#f5f6f8}.demo-panel .du.cur{background:var(--accent-soft)}.demo-panel .df{border-top:1px solid var(--line);gap:8px;padding:12px 16px;display:flex}.answer-review{border:1px solid var(--line);border-radius:10px;margin-bottom:12px;padding:14px 16px}.answer-review .ah{align-items:flex-start;gap:10px;margin-bottom:8px;display:flex}.answer-review .ah .t{flex:1;font-weight:500}.answer-review .given{white-space:pre-line;background:#fafbfc;border-radius:8px;padding:10px 12px}.answer-review.ok{border-left:3px solid var(--ok)}.answer-review.bad{border-left:3px solid var(--bad)}.answer-review.free{border-left:3px solid var(--warn)}@media (width<=900px){.editor-shell,.grid2,.grid3,.login-wrap,.mail{grid-template-columns:1fr}.login-side{display:none}.sidebar{width:72px}.content{padding:16px}}.q-edit .qn{white-space:nowrap}.lesson-nav .item .btn{display:none}.lesson-nav .item:hover .btn,.lesson-nav .item.active .btn{display:inline-flex}.card:has(>.table){overflow-x:auto}