:root{color-scheme:light dark;--bg:#f3f6f9;--surface:#fff;--ink:#18324b;--muted:#52677a;--line:#d3dfe8;--accent:#205f9a;--tint:#e8f1fa;--good:#16623e;--bad:#a22e30;--warning:#fff3db;--warning-ink:#704900}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 Arial,"DejaVu Sans",sans-serif}a{color:var(--accent);text-underline-offset:3px}button,input,textarea,select{font:inherit}button,a,input,textarea,summary{touch-action:manipulation}button,.button{cursor:pointer}button:disabled{cursor:default;opacity:.65}:focus-visible{outline:3px solid var(--accent);outline-offset:4px}main:focus-visible{outline:none}h1,h2,h3,p{margin-top:0}h1{font-size:clamp(1.8rem,4vw,2.5rem);line-height:1.25;margin-bottom:12px;letter-spacing:-.025em}h2{font-size:1.3rem;line-height:1.4;margin-bottom:12px}h3{font-size:1.08rem;line-height:1.45;margin-bottom:8px}p{margin-bottom:14px}small,.muted{color:var(--muted)}small{font-size:.86rem}.shell{display:grid;grid-template-columns:246px minmax(0,1fr);min-height:100dvh}.sidebar{position:sticky;top:0;height:100dvh;padding:30px 18px 22px;border-right:1px solid var(--line);background:var(--surface);display:flex;flex-direction:column}.brand{display:flex;gap:12px;align-items:center;text-decoration:none;color:var(--ink);font-size:1.18rem;font-weight:700;margin:0 8px 36px}.brand small{display:block;font-size:.7rem;font-weight:400;margin-top:3px}.brand-mark{display:grid;place-items:center;flex:none;width:44px;height:44px;background:var(--accent);color:#fff;border-radius:12px;font-size:1.1rem}.sidebar nav{display:grid;gap:6px}.sidebar nav a{min-height:48px;padding:11px 13px;text-decoration:none;color:var(--muted);border-radius:10px;font-size:.94rem;font-weight:600}.sidebar nav a:hover,.sidebar nav a[aria-current]{color:var(--accent);background:var(--tint)}#review-count:not(:empty){margin-left:5px;border:1px solid var(--line);border-radius:5px;padding:0 5px;font-size:.8rem}.sidebar-note{margin-top:auto;padding:26px 12px 0;font-size:.84rem}.sidebar-note p{margin:12px 0}.sidebar-note strong{font-weight:600}.topbar{min-height:72px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;gap:16px;padding:16px 38px;background:var(--surface);font-size:.88rem;color:var(--muted)}.level,.tag{display:inline-block;font-size:.78rem;font-weight:700;padding:5px 10px;border:1px solid var(--line);border-radius:6px;color:var(--accent);background:var(--surface)}main{padding:36px 38px 44px;max-width:1220px;margin:auto;min-height:70dvh;outline:none}main>section+section{margin-top:32px}.intro{max-width:760px;color:var(--muted)}.welcome{display:grid;grid-template-columns:minmax(0,1.6fr) minmax(230px,1fr);gap:28px;padding:30px;border-radius:16px;background:var(--tint);border:1px solid var(--line);margin:26px 0}.welcome h2{font-size:1.55rem}.welcome p{max-width:54ch}.welcome-side{border-left:1px solid var(--line);padding-left:26px;display:flex;flex-direction:column;justify-content:center}.big-number{font-size:2.5rem;font-weight:700;line-height:1.3}.actions{display:flex;align-items:center;flex-wrap:wrap;gap:10px;margin:18px 0 4px}.button,button.primary{display:inline-flex;align-items:center;justify-content:center;min-height:46px;border-radius:9px;padding:10px 18px;border:1px solid var(--accent);background:var(--accent);color:#fff;font-weight:600;text-decoration:none;font-size:.9rem}.button.secondary{background:var(--surface);color:var(--accent);border-color:var(--line)}button:active,.button:active{transform:translateY(1px)}.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.card{padding:24px;background:var(--surface);border:1px solid var(--line);border-radius:13px;min-width:0}.card p:last-child{margin-bottom:0}.card-link{color:var(--ink);text-decoration:none;display:block}.card-link:hover{border-color:var(--accent)}.card-link h2,.card-link h3{color:var(--accent)}.card .tag{margin-bottom:12px}.card small{display:block}.card-bottom{display:flex;justify-content:space-between;gap:16px;align-items:center;margin-top:16px;font-size:.85rem}.card-bottom strong{color:var(--accent)}.section-heading{margin:30px 0 16px}.stats{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin:24px 0}.stat{padding:20px 24px;border:1px solid var(--line);border-radius:12px;background:var(--surface)}.stat strong{display:block;font-size:1.8rem;line-height:1.3;margin-bottom:8px}.stat span{font-size:.87rem;color:var(--muted)}.notice{padding:18px 20px;background:var(--tint);border-left:3px solid var(--accent);border-radius:0 10px 10px 0;margin:22px 0;font-size:.92rem}.warning{background:var(--warning);color:var(--warning-ink)}#storage-warning{margin:20px 38px 0}.back{display:inline-block;margin-bottom:22px;min-height:36px}.rule{margin:18px 0;padding:24px;border:1px solid var(--line);border-radius:12px;background:var(--surface)}.examples{margin-top:16px;display:grid;gap:10px}.example{padding:12px 16px;background:var(--bg);border-radius:8px}.example p{margin:0}.example small{display:block;margin-top:4px}.vocab{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.vocab .example{border:1px solid var(--line);background:var(--surface);padding:18px}.vocab .example strong{font-size:1.12rem}.dialogue p{padding:10px 0;border-bottom:1px solid var(--line);margin:0}.dialogue p:last-child{border:0}.dialogue small{display:block}.question{margin:18px 0;padding:24px;border:1px solid var(--line);border-radius:12px;background:var(--surface);min-width:0}.question legend{font-weight:700;padding:0 4px;max-width:100%;overflow-wrap:anywhere}.option{display:flex;align-items:flex-start;gap:12px;padding:12px 14px;border:1px solid var(--line);border-radius:9px;margin:9px 0;cursor:pointer;min-height:49px}.option:has(input:checked){border-color:var(--accent);background:var(--tint)}.option input{margin:6px 0 0;accent-color:var(--accent);flex:none;width:17px;height:17px}.feedback{margin:16px 0 0}.feedback:empty{display:none}.feedback strong{display:block}.feedback.good strong{color:var(--good)}.feedback.bad strong{color:var(--bad)}.question button{margin-top:7px}.reading-text{white-space:pre-line;background:var(--bg);padding:20px;border-radius:9px;line-height:1.85}.practice-block{margin-bottom:26px}.practice-block>h2{margin-bottom:6px}details{margin:18px 0;border:1px solid var(--line);padding:15px 18px;border-radius:10px;background:var(--surface)}summary{cursor:pointer;font-weight:600;color:var(--accent);min-height:28px}details[open] summary{margin-bottom:16px}audio{width:100%;margin:14px 0;min-width:0}label.field-label{display:block;font-weight:600;margin:18px 0 8px}textarea{display:block;width:100%;min-height:170px;resize:vertical;max-width:100%;color:var(--ink);background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:16px;line-height:1.7}textarea::placeholder{color:var(--muted)}.checklist{padding-left:22px}.checklist li{margin:8px 0}.save-state{display:block;font-size:.85rem;color:var(--muted);margin:6px 0}.file-label{display:inline-flex;cursor:pointer}.file-label input{max-width:100%;margin-top:6px}.progress-row{padding:15px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;align-items:center;gap:20px}.progress-row a{font-weight:600}.progress-row span{white-space:nowrap;font-size:.88rem}footer{padding:24px 38px 32px;border-top:1px solid var(--line);display:flex;flex-direction:column;gap:8px;color:var(--muted);font-size:.78rem}footer strong{color:var(--ink)}.skip{position:fixed;top:-80px;left:16px;z-index:2;background:var(--surface);padding:12px}.skip:focus{top:10px}.loading{min-height:200px;padding-top:35px;color:var(--muted)}[hidden]{display:none!important}
@media(prefers-color-scheme:dark){:root{--bg:#111e2b;--surface:#192b3c;--ink:#e8f0f7;--muted:#b4c4d2;--line:#385066;--accent:#9acbfa;--tint:#233e55;--good:#90dbb4;--bad:#ffb0ae;--warning:#423720;--warning-ink:#ffe0a2}.button,button.primary,.brand-mark{color:#142d45}}
@media(max-width:900px){.shell{grid-template-columns:210px minmax(0,1fr)}.sidebar{padding:24px 12px}.brand{font-size:1.06rem;gap:8px}.brand small{font-size:.66rem}main{padding:26px 24px}.topbar{padding:16px 24px}.welcome{grid-template-columns:1fr}.welcome-side{padding:18px 0 0;border-left:0;border-top:1px solid var(--line)}.stats{gap:10px}.stat{padding:16px}.grid{gap:12px}.card{padding:20px}}
@media(max-width:700px){.shell{display:block}.sidebar{position:static;height:auto;padding:18px 16px 12px;border-right:0;border-bottom:1px solid var(--line)}.brand{margin:0 0 16px}.sidebar nav{grid-template-columns:repeat(3,minmax(0,1fr));gap:4px}.sidebar nav a{font-size:.77rem;padding:10px 5px;text-align:center;display:grid;place-content:center}.sidebar-note{display:none}.topbar{min-height:52px;padding:10px 20px;font-size:.8rem}main{padding:26px 18px 32px}.grid,.vocab{grid-template-columns:1fr}.welcome{padding:22px;gap:12px;margin:22px 0}.stats{grid-template-columns:repeat(3,minmax(0,1fr));gap:8px}.stat{padding:12px 10px}.stat strong{font-size:1.5rem}.stat span{font-size:.73rem}.question,.rule,.card{padding:19px}.question legend{font-size:.95rem}.option{padding:12px;font-size:.95rem}.progress-row{gap:10px}.progress-row a{font-size:.9rem}footer{padding:24px 18px}#storage-warning{margin:16px 18px 0}h2{font-size:1.22rem}.actions .button{flex-grow:1}.reading-text{padding:15px}.file-label{display:block}.file-label input{width:100%}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}button:active,.button:active{transform:none}}