:root{color:#172536;font-synthesis:none;--surface:#fff;--surface-soft:#f7f9fb;--sidebar:#edf2f7;--line:#d8e0e8;--muted:#617184;--accent:#245fc2;--accent-dark:#174a9b;--accent-soft:#e7effc;--warning-soft:#fff5d9;--warning-ink:#6d4b00;--success:#247155;background:#f5f7fa;font-family:Inter,-apple-system,BlinkMacSystemFont,Segoe UI,sans-serif}*{box-sizing:border-box}body{color:#172536;background:#f5f7fa;min-width:320px;min-height:100vh;margin:0}button,select{font:inherit}button{color:inherit}button:focus-visible,select:focus-visible,a:focus-visible{outline-offset:2px;outline:3px solid #f5bf2f}.app-shell{min-height:100vh}.topbar{background:var(--surface);border-bottom:1px solid var(--line);justify-content:space-between;align-items:center;height:64px;padding:0 28px;display:flex}.brand{color:inherit;letter-spacing:-.02em;align-items:center;gap:10px;font-weight:760;text-decoration:none;display:flex}.brand em{border-left:1px solid var(--line);color:var(--muted);letter-spacing:0;padding-left:10px;font-size:13px;font-style:normal;font-weight:620}.brand-mark{grid-template-columns:repeat(3,1fr);align-items:end;gap:3px;width:27px;height:27px;display:grid}.brand-mark i{background:#245fc2;border-radius:2px;height:11px;display:block}.brand-mark i:nth-child(2){background:#ef654f;height:21px}.brand-mark i:nth-child(3){background:#f5bf2f;height:16px}.teacher{text-align:right;line-height:1.25;display:grid}.teacher span{color:var(--muted);font-size:12px}.teacher strong{font-size:14px}.demo-banner{background:var(--warning-soft);min-height:36px;color:var(--warning-ink);text-align:center;border-bottom:1px solid #eadcae;padding:8px 28px;font-size:13px;font-weight:600}.workspace{grid-template-columns:230px minmax(0,1fr);min-height:calc(100vh - 100px);display:grid}.sidebar{background:var(--sidebar);border-right:1px solid var(--line);flex-direction:column;gap:24px;padding:24px 16px;display:flex}.sidebar nav{gap:4px;display:grid}.nav-item{color:#425469;cursor:pointer;text-align:left;background:0 0;border:0;border-radius:9px;justify-content:space-between;align-items:center;width:100%;min-height:42px;padding:9px 12px;font-size:14px;font-weight:630;display:flex}.nav-item:hover{background:#ffffffa8}.nav-item.active{background:var(--surface);color:var(--accent-dark);box-shadow:0 1px 2px #14284614}.nav-item b{background:var(--accent-soft);min-width:22px;color:var(--accent-dark);text-align:center;border-radius:10px;padding:2px 6px;font-size:11px}.sidebar-note{border-top:1px solid var(--line);gap:2px;margin-top:auto;padding:14px 12px;display:grid}.sidebar-note span,.sidebar-note small{color:var(--muted);font-size:12px}.sidebar-note strong{font-size:14px}.main-content{min-width:0;padding:32px clamp(20px,3.5vw,52px) 56px}.page-heading{justify-content:space-between;align-items:flex-start;gap:24px;min-height:66px;display:flex}.page-heading h1{letter-spacing:-.025em;margin:0;font-size:26px;line-height:1.2}.page-heading p{max-width:680px;color:var(--muted);margin:7px 0 0;font-size:14px}.page-heading select{border:1px solid var(--line);background:var(--surface);color:#28394c;border-radius:9px;min-width:170px;padding:9px 34px 9px 11px}.heading-actions{flex-wrap:wrap;justify-content:flex-end;gap:8px;display:flex}.filters{border-bottom:1px solid var(--line);gap:4px;margin:24px 0 12px;display:flex}.filter{color:var(--muted);cursor:pointer;background:0 0;border:0;border-bottom:2px solid #0000;padding:9px 12px 10px;font-size:14px;font-weight:650}.filter span{color:#8290a0;margin-left:5px}.filter.active{color:var(--accent-dark);border-color:var(--accent)}.inbox-layout{grid-template-columns:minmax(280px,.78fr) minmax(420px,1.22fr);align-items:start;gap:16px;display:grid}.task-list,.detail-panel,.empty-state,.library-grid button,.lesson-list{background:var(--surface);border:1px solid var(--line);border-radius:12px}.task-list{overflow:hidden}.task-row{border:0;border-bottom:1px solid var(--line);cursor:pointer;text-align:left;background:0 0;grid-template-columns:10px 1fr auto;align-items:start;gap:12px;width:100%;min-height:88px;padding:16px;display:grid}.task-row:last-of-type{border-bottom:0}.task-row:hover{background:var(--surface-soft)}.task-row.selected{background:var(--accent-soft);box-shadow:inset 3px 0 var(--accent)}.status-dot{background:var(--accent);border-radius:50%;width:8px;height:8px;margin-top:6px}.status-dot.viewed{background:#a3afbb}.status-dot.selected-dot{background:var(--success)}.task-row-copy{gap:7px;display:grid}.task-row-copy strong{font-size:14px;line-height:1.35}.task-row-copy small,.task-time{color:var(--muted);font-size:12px}.task-time{white-space:nowrap}.list-empty{color:var(--muted);padding:24px;font-size:14px}.detail-panel{padding:24px}.detail-head{justify-content:space-between;gap:24px;display:flex}.task-code{color:var(--muted);letter-spacing:.07em;font-size:11px;font-weight:700}.detail-head h2{letter-spacing:-.02em;max-width:560px;margin:6px 0 0;font-size:22px;line-height:1.25}.duration{color:var(--muted);flex:none;font-size:13px}.task-facts{border-top:1px solid var(--line);border-bottom:1px solid var(--line);grid-template-columns:repeat(3,1fr);gap:16px;margin:24px 0;padding:16px 0;display:grid}.task-facts div{gap:3px;display:grid}.task-facts dt{color:var(--muted);font-size:12px}.task-facts dd{margin:0;font-size:14px;font-weight:650}.reason-box{background:var(--surface-soft);border-radius:9px;padding:14px 16px}.reason-box span{color:var(--muted);font-size:12px;font-weight:650}.reason-box p{margin:6px 0 0;font-size:14px;line-height:1.5}.detail-actions{flex-wrap:wrap;align-items:center;gap:9px;margin-top:20px;display:flex}.button{cursor:pointer;border:1px solid #0000;border-radius:9px;min-height:40px;padding:9px 15px;font-size:14px;font-weight:680;transition:background-color .16s,border-color .16s}.button.primary{background:var(--accent);color:#fff}.button.primary:hover{background:var(--accent-dark)}.button.secondary{background:var(--surface);border-color:var(--line)}.button.secondary:hover{background:var(--surface-soft)}.button:disabled{opacity:.48;cursor:not-allowed}.text-button{color:var(--accent-dark);cursor:pointer;background:0 0;border:0;padding:8px;font-size:13px;font-weight:650}.text-button:disabled{color:var(--muted);cursor:default}.student-preview{border:1px solid var(--line);background:#fbfcfe;border-radius:10px;margin-top:24px;padding:20px}.preview-bar{color:var(--muted);justify-content:space-between;gap:12px;font-size:11px;font-weight:650;display:flex}.student-preview h3{max-width:580px;margin:26px 0 20px;font-size:19px;line-height:1.4}.pattern{flex-wrap:wrap;gap:10px;margin-bottom:22px;display:flex}.pattern-shape,.pattern-missing{border:1px solid var(--line);background:#fff;border-radius:9px;place-items:center;width:46px;height:46px;font-size:24px;display:grid}.tone-0{color:#ef654f}.tone-1{color:#d89d00}.tone-2{color:#245fc2}.pattern-missing{color:var(--muted);border-style:dashed}.answer-list{gap:8px;display:grid}.answer{border:1px solid var(--line);cursor:pointer;text-align:left;background:#fff;border-radius:9px;align-items:center;gap:10px;min-height:44px;padding:9px 12px;font-size:14px;display:flex}.answer:hover{border-color:#9eb3ca}.answer.selected{border-color:var(--accent);background:var(--accent-soft)}.answer span{background:#edf1f5;border-radius:50%;place-items:center;width:24px;height:24px;font-size:11px;font-weight:750;display:grid}.preview-actions{justify-content:flex-end;gap:8px;margin-top:16px;display:flex}.hint{background:var(--warning-soft);color:var(--warning-ink);border-radius:8px;margin:14px 0 0;padding:10px 12px;font-size:13px}.feedback{border-radius:8px;margin:10px 0 0;padding:10px 12px;font-size:13px}.feedback.success{color:#175e46;background:#e4f3ec}.feedback.retry{color:#853727;background:#fbe9e5}.single-sheet-preview{border:1px solid var(--line);background:#fff;border-radius:10px;margin-top:24px;padding:22px}.packet-controls{border:1px solid var(--line);background:var(--surface);border-radius:10px;justify-content:space-between;align-items:center;gap:16px;margin:22px 0 18px;padding:12px 14px;display:flex}.packet-controls label{align-items:center;gap:9px;font-size:14px;font-weight:620;display:flex}.packet-controls input{width:17px;height:17px;accent-color:var(--accent)}.print-packet{gap:24px;display:grid}.worksheet-page{color:#111820;background:#fff;flex-direction:column;width:min(100%,794px);min-height:1028px;margin:0 auto;padding:48px 54px 38px;display:flex;box-shadow:0 3px 8px #1e37551f}.worksheet-header{border-bottom:2px solid #172536;justify-content:space-between;gap:24px;padding-bottom:18px;display:flex}.worksheet-header>div{gap:4px;display:grid}.worksheet-header strong{font-size:18px}.worksheet-header span{color:#4d5d6e;font-size:12px}.student-fields{text-align:right}.worksheet-body{gap:0;display:grid}.worksheet-exercise{border-bottom:1px solid #aeb9c4;min-height:405px;padding:30px 0}.worksheet-exercise:last-child{border-bottom:0}.worksheet-exercise.compact{border:0;min-height:0;padding:0}.exercise-heading{align-items:flex-start;gap:14px;display:flex}.exercise-heading>span{border:2px solid #172536;border-radius:50%;flex:none;place-items:center;width:30px;height:30px;font-size:13px;font-weight:800;display:grid}.exercise-heading small{color:#536273;font-size:11px}.exercise-heading h3{letter-spacing:-.015em;margin:2px 0 0;font-size:18px}.exercise-instruction{margin:18px 0;font-size:15px}.word-task{border:1px solid #9ba8b6;gap:8px;margin:20px 0;padding:16px;display:grid}.word-task span{color:#536273;font-size:11px}.word-task strong{letter-spacing:.03em;font-size:15px}.choice-task{flex-wrap:wrap;gap:18px;margin:20px 0;font-size:14px;display:flex}.writing-lines{gap:18px;margin-top:24px;display:grid}.writing-lines i,.teacher-notes i{border-bottom:1px solid #7a8794;display:block}.worksheet-footer{color:#647181;text-align:center;border-top:1px solid #c3ccd5;margin-top:auto;padding-top:12px;font-size:10px}.teacher-sheet>p{color:#3e4d5c;margin:26px 0 18px;font-size:13px}.observation-table{border-top:1px solid #8d9aa7}.observation-table>div{border-bottom:1px solid #c3ccd5;grid-template-columns:24px 1.4fr repeat(3,.85fr);align-items:center;gap:8px;min-height:42px;font-size:10px;display:grid}.observation-table b{font-size:11px}.observation-table em{font-style:normal}.teacher-notes{gap:18px;margin-top:28px;font-size:12px;display:grid}.library-grid{grid-template-columns:repeat(3,1fr);gap:14px;margin-top:24px;display:grid}.library-grid button{cursor:pointer;text-align:left;flex-direction:column;align-items:flex-start;gap:10px;min-height:150px;padding:18px;display:flex}.library-grid button:hover{border-color:#aab9c8}.library-grid span,.library-grid small{color:var(--muted);font-size:12px}.library-grid strong{font-size:15px;line-height:1.4}.library-grid small{margin-top:auto}.lesson-list{margin-top:24px;overflow:hidden}.lesson-list>div{border-bottom:1px solid var(--line);grid-template-columns:30px 1fr auto;align-items:center;gap:12px;min-height:72px;padding:14px 18px;display:grid}.lesson-list>div:last-child{border-bottom:0}.lesson-list>div>span{background:var(--accent-soft);width:26px;height:26px;color:var(--accent-dark);border-radius:50%;place-items:center;font-size:12px;font-weight:750;display:grid}.lesson-list>div>div{gap:4px;display:grid}.lesson-list small{color:var(--muted)}.empty-state{text-align:center;place-content:center;min-height:240px;margin-top:24px;padding:36px;display:grid}.empty-state h2{margin:0;font-size:20px}.empty-state p{max-width:430px;color:var(--muted);margin:8px 0 0;font-size:14px}.empty-detail{color:var(--muted);padding:30px}.access-page{background:#eef3f8;place-items:center;min-height:100vh;padding:24px;display:grid}.access-card{border:1px solid var(--line);background:var(--surface);border-radius:12px;gap:14px;width:min(100%,390px);padding:32px;display:grid;box-shadow:0 18px 45px #1e37551a}.access-card h1{letter-spacing:-.025em;margin:8px 0 0;font-size:24px}.access-card p{color:var(--muted);margin:0 0 6px;font-size:14px}.access-card label{font-size:13px;font-weight:680}.access-card input{border:1px solid var(--line);color:#172536;width:100%;height:46px;font:inherit;letter-spacing:.3em;background:#fff;border-radius:9px;padding:8px 12px;font-size:20px}.access-card small{color:var(--muted);text-align:center;font-size:12px}.access-error{color:#8a3325;font-size:13px}@media (width<=900px){.workspace{grid-template-columns:1fr}.sidebar{border-right:0;border-bottom:1px solid var(--line);padding:10px 16px;overflow-x:auto}.sidebar nav{min-width:max-content;display:flex}.nav-item{width:auto}.sidebar-note{display:none}.inbox-layout{grid-template-columns:1fr}.library-grid{grid-template-columns:repeat(2,1fr)}}@media (width<=600px){.topbar{height:58px;padding:0 16px}.brand em,.teacher span{display:none}.demo-banner{padding-inline:16px;font-size:12px}.main-content{padding:24px 16px 40px}.page-heading{gap:16px;display:grid}.page-heading select{width:100%}.task-facts{grid-template-columns:1fr 1fr}.detail-panel{padding:18px}.detail-head{gap:8px;display:grid}.library-grid{grid-template-columns:1fr}.preview-bar{display:grid}.preview-actions{justify-content:stretch}.preview-actions .button{flex:1}}@media (prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}@page{size:A4 portrait;margin:0}@media print{:root{background:#fff}body{-webkit-print-color-adjust:exact;print-color-adjust:exact;background:#fff}.topbar,.demo-banner,.sidebar,.page-heading,.packet-controls{display:none!important}.workspace,.main-content,.print-packet{margin:0;padding:0;display:block}.worksheet-page{width:210mm;min-height:297mm;box-shadow:none;break-after:page;page-break-after:always;margin:0;padding:15mm 17mm 12mm}.worksheet-page:last-child{break-after:auto;page-break-after:auto}.worksheet-exercise{min-height:119mm}}