:root{--ink:#18233f;--muted:#6e7892;--line:#dfe4f1;--purple:#6655e8;--paper:#f6f5fb}*{box-sizing:border-box}body{margin:0;background:radial-gradient(circle at 85% 0,#e9e6ff 0,transparent 28%),var(--paper);color:var(--ink);font-family:system-ui,-apple-system,"Segoe UI","Microsoft YaHei","PingFang SC",Arial,sans-serif}.hidden{display:none!important}button,input{font:inherit}.practice-topbar{height:72px;padding:0 max(22px,calc((100vw - 1240px)/2));display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid rgba(216,221,237,.9);background:rgba(255,255,255,.82);backdrop-filter:blur(16px);position:sticky;top:0;z-index:20}.back-home{text-decoration:none;color:#4d5874;font-weight:800}.practice-brand{display:flex;align-items:center;gap:10px}.practice-brand>span{width:40px;height:40px;border-radius:13px;display:grid;place-items:center;background:linear-gradient(135deg,#7456ef,#3c7df5);color:#fff;font-weight:900}.practice-brand b,.practice-brand small{display:block}.practice-brand small{color:#8b94aa;font-size:10px;letter-spacing:.12em;margin-top:2px}main{width:min(1240px,calc(100% - 36px));margin:0 auto;padding:42px 0 70px}.practice-hero{display:grid;grid-template-columns:1.4fr 1fr;align-items:end;gap:30px;padding:38px;border-radius:30px;background:linear-gradient(135deg,#5c4bd8,#417cf2);color:#fff;box-shadow:0 24px 54px rgba(66,65,164,.18)}.eyebrow{font-size:12px;font-weight:900;letter-spacing:.16em;opacity:.75}.practice-hero h1{font-size:44px;line-height:1.1;margin:9px 0 13px}.practice-hero p{max-width:680px;margin:0;color:rgba(255,255,255,.82);font-size:17px;line-height:1.75}.hero-counts{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}.hero-counts div{padding:18px 12px;border:1px solid rgba(255,255,255,.2);border-radius:18px;background:rgba(255,255,255,.1);text-align:center}.hero-counts b,.hero-counts span{display:block}.hero-counts b{font-size:26px}.hero-counts span{font-size:11px;opacity:.72;margin-top:3px}.practice-tools{display:flex;justify-content:space-between;gap:18px;margin:30px 0 14px}.practice-search{height:48px;min-width:300px;flex:1;display:flex;align-items:center;gap:9px;padding:0 16px;border:1px solid var(--line);border-radius:15px;background:#fff}.practice-search span{font-size:22px;color:#78839d}.practice-search input{width:100%;border:0;outline:0;color:var(--ink);background:transparent}.display-switch{display:flex;padding:4px;border-radius:15px;background:#e8e8f7}.display-switch button{border:0;border-radius:12px;padding:10px 15px;background:transparent;color:#6d7691;font-weight:800;cursor:pointer}.display-switch button.active{background:#fff;color:#5947dd;box-shadow:0 4px 13px rgba(51,59,114,.11)}.category-list{display:flex;gap:8px;overflow-x:auto;padding:4px 0 20px;scrollbar-width:none}.category-list::-webkit-scrollbar{display:none}.category-list button{flex:0 0 auto;border:1px solid var(--line);border-radius:999px;background:#fff;color:#66718b;padding:9px 14px;font-size:13px;font-weight:800;cursor:pointer}.category-list button.active{border-color:#6655e8;background:#6655e8;color:#fff}.dialogue-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}.dialogue-card{min-width:0;border:1px solid var(--line);border-radius:24px;background:#fff;overflow:hidden;box-shadow:0 10px 28px rgba(44,54,99,.07);transition:transform .16s,border-color .16s}.dialogue-card:hover{transform:translateY(-2px);border-color:#aaa0ef}.dialogue-card.learned{border-color:#9bd8c0}.dialogue-card>header{display:flex;justify-content:space-between;gap:16px;padding:22px 22px 18px;background:linear-gradient(135deg,#fafaff,#f2f6ff)}.dialogue-card header small{color:#6554e3;font-size:10px;font-weight:900;letter-spacing:.12em}.dialogue-card h2{font-size:21px;margin:5px 0 7px}.dialogue-card header p{margin:0;color:var(--muted);font-size:13px;line-height:1.55}.learn-button{flex:0 0 auto;align-self:flex-start;border:1px solid #d9def0;border-radius:11px;background:#fff;color:#66718d;padding:8px 10px;font-size:11px;font-weight:800;cursor:pointer}.learned .learn-button{border-color:#b9e6d3;background:#e9f8f2;color:#27785a}.dialogue-lines{padding:8px 22px}.dialogue-line{display:grid;grid-template-columns:58px minmax(0,1fr) 38px;gap:10px;align-items:start;padding:14px 0;border-bottom:1px solid #edf0f6}.dialogue-line:last-child{border-bottom:0}.dialogue-line>span{display:inline-block;width:max-content;max-width:58px;padding:5px 7px;border-radius:8px;background:#eeecff;color:#5f4ddd;font-size:10px;font-weight:900}.dialogue-line b,.dialogue-line p{display:block;margin:0;line-height:1.55}.dialogue-line b{font-size:15px}.dialogue-line p{color:var(--muted);font-size:13px;margin-top:4px}.speak-line{width:34px;height:34px;border:0;border-radius:50%;background:#eef2ff;color:#5e51dc;cursor:pointer}.dialogue-card>footer{display:grid;grid-template-columns:minmax(130px,.85fr) 1.4fr;gap:14px;padding:17px 22px;background:#f8f9fc;border-top:1px solid #edf0f6}.dialogue-card footer small,.dialogue-card footer b{display:block}.dialogue-card footer small{color:#8a93a8;font-size:10px;font-weight:800}.dialogue-card footer b{font-size:13px;color:#4f43c6;margin-top:3px}.dialogue-card footer p{margin:0;color:#68738e;font-size:12px;line-height:1.6}.empty-state{text-align:center;color:#7e88a0;padding:50px}.practice-toast{position:fixed;left:50%;bottom:28px;transform:translate(-50%,20px);padding:11px 16px;border-radius:12px;background:#202a44;color:#fff;font-size:13px;opacity:0;pointer-events:none;transition:.18s;z-index:50}.practice-toast.show{opacity:1;transform:translate(-50%,0)}
@media(max-width:820px){html,body{width:100%;max-width:100%;overflow-x:hidden}.practice-topbar{height:62px;padding:0 14px}.practice-brand{display:none}main{width:calc(100% - 22px);max-width:680px;padding:18px 0 50px;overflow:hidden}.practice-hero,.practice-tools,.category-list,.dialogue-grid{width:100%;max-width:100%}.practice-hero{grid-template-columns:minmax(0,1fr);padding:24px 20px;border-radius:23px;gap:22px}.practice-hero h1{font-size:34px}.practice-hero p{font-size:14px}.hero-counts{grid-template-columns:repeat(2,minmax(0,1fr));gap:7px}.hero-counts div{min-width:0;padding:14px 3px}.hero-counts div:last-child{grid-column:1/-1}.hero-counts b{font-size:22px}.hero-counts span{font-size:10px}.practice-tools{display:block;margin-top:18px}.practice-search{min-width:0;width:100%}.display-switch{width:100%;display:grid;grid-template-columns:repeat(3,minmax(0,1fr));margin-top:10px}.display-switch button{min-width:0;padding:10px 3px;font-size:12px}.dialogue-grid{grid-template-columns:minmax(0,1fr)}.dialogue-card{width:100%;max-width:100%;min-width:0}.dialogue-card>header{padding:19px 17px 15px}.dialogue-lines{padding:6px 14px}.dialogue-line{grid-template-columns:44px minmax(0,1fr) 30px;gap:7px}.dialogue-line>div{min-width:0}.dialogue-line b,.dialogue-line p{overflow-wrap:anywhere}.speak-line{width:30px;height:30px}.dialogue-card>footer{grid-template-columns:1fr;padding:15px 17px}}
.practice-controls{position:sticky;top:72px;z-index:19;margin-top:24px;padding:12px 0 0;background:rgba(246,245,251,.97);backdrop-filter:blur(16px);border-bottom:1px solid var(--line)}
.practice-controls .practice-tools{margin:0 0 10px}
.practice-controls .category-list{padding-bottom:12px}
.category-list button span{margin-left:7px;opacity:.65;font-size:12px}.practice-organize{display:flex;gap:18px;flex-wrap:wrap;align-items:center}.practice-organize label{display:flex;align-items:center;gap:8px;font-size:14px;color:#596781}.practice-organize select{border:1px solid #e1e5f5;border-radius:10px;padding:9px 12px;background:white;color:#26324e;font:inherit;max-width:180px}.result-summary{font-size:13px;color:#74839f;margin:10px 0 14px;scroll-margin-top:240px}.dialogue-card header{position:relative;padding-left:62px}.practice-pin-first{position:absolute;left:18px;top:26px;width:30px;height:30px;border:1px solid #e2e5f4;border-radius:50%;background:white;color:#6d7590;cursor:pointer}.practice-pin-first.active{background:#6652ed;color:white}.practice-explanation{padding:20px 24px;border-top:1px solid #e8ecf7}.practice-explanation summary{color:#6652ed;font-weight:700;cursor:pointer}.practice-explanation section{margin-top:22px}.practice-explanation h3{font-size:16px;margin-bottom:8px;color:#26324e}.practice-explanation p{font-size:15px;line-height:1.9;color:#596781;white-space:pre-line}.practice-pagination{display:flex;justify-content:center;align-items:center;gap:20px;margin:28px 0}.practice-pagination button{border:1px solid #dddff0;border-radius:12px;padding:12px 22px;background:white;color:#6652ed;cursor:pointer}.practice-pagination button:disabled{opacity:.4;cursor:default}.dialogue-grid{align-items:start}@media(max-width:820px){.practice-organize{gap:8px}.practice-organize select{max-width:135px}.result-summary{scroll-margin-top:300px}.practice-explanation{padding:18px}.dialogue-card header{padding-left:55px}.practice-pin-first{left:14px}}
@media(max-width:820px){html,body{overflow-x:clip}main{overflow:visible}.practice-controls{top:62px;margin-top:18px;padding-top:10px}.practice-controls .practice-tools{margin-top:0}.practice-controls .category-list{padding-bottom:10px}}
.knowledge-reveal{display:block;max-width:calc(100% - 44px);margin:12px 22px 20px;padding:10px 14px;border:1px solid var(--line);border-radius:12px;background:#f4f2ff;color:#5947dd;font:inherit;font-size:13px;font-weight:700;cursor:pointer}.knowledge-reveal:focus-visible{outline:2px solid var(--purple);outline-offset:3px}