:root{--ink:#24364b;--green:#3466b0;--accent:#3466b0;--cream:#f5f7fa;--muted:#7b8797;--line:#e6eaf0;--gold:#7d8ca4;--word:#eaf0fb}*{box-sizing:border-box}body{margin:0;color:var(--ink);background:var(--cream);font-family:system-ui,-apple-system,"PingFang SC","Microsoft YaHei",sans-serif;font-size:14px}button,input,select,textarea{font:inherit}button{cursor:pointer;border:1px solid var(--line);background:white;border-radius:8px;padding:9px 14px;color:var(--ink);transition:background .15s,border-color .15s}button:hover{border-color:#b7c9e6;background:#f1f5fc}button:focus-visible,a:focus-visible,input:focus-visible{outline:3px solid #9bbbe8;outline-offset:3px}button:disabled{opacity:.35;cursor:default}button.primary,button.active{background:var(--accent);color:white;border-color:var(--accent)}button.primary:hover{background:#285793}header{height:72px;display:flex;justify-content:space-between;align-items:center;padding:0 max(24px,calc((100vw - 1360px)/2));border-bottom:1px solid var(--line);background:white;gap:18px}.brand{display:flex;align-items:center;gap:10px;color:var(--ink);text-decoration:none;white-space:nowrap}.brand b{font-size:18px;letter-spacing:1px}.brand-mark{width:32px;height:34px;display:flex;justify-content:center;align-items:center;background:var(--accent);color:white;font-size:19px;border-radius:9px 9px 9px 2px}.brand small{font-size:9px;letter-spacing:2px;color:#9aa5b4;border-left:1px solid var(--line);padding-left:12px}nav{display:flex;gap:7px;flex-wrap:wrap}nav button{border:0;background:transparent;font-size:13px;color:#637085;padding:8px 10px}nav #account{border:1px solid var(--line);color:var(--accent);background:#f7f9fd}main{max-width:1250px;margin:auto;padding:36px 28px}.eyebrow{font-size:10px;font-weight:650;color:var(--accent);letter-spacing:2.5px}.hero{display:grid;grid-template-columns:1fr 210px;padding:32px 36px;background:linear-gradient(120deg,#eaf0fb,#f3f6fd);border:1px solid #dee6f3;border-radius:14px;gap:32px;margin-bottom:28px}.hero h1{font-size:30px;line-height:1.45;letter-spacing:1px;margin:12px 0}.hero p{color:#6b7c93;line-height:1.9;margin:0 0 22px}.hero-art{display:flex;align-items:center;justify-content:center;font:64px Georgia;color:#9caecd;border-left:1px solid #d5deee;line-height:1.2}.stats{display:flex;gap:36px}.stats b{display:block;font:25px Georgia;color:#425e87}.stats span{font-size:11px;color:var(--muted)}.row{display:flex;gap:10px;align-items:center;flex-wrap:wrap;justify-content:space-between}.filters{display:flex;gap:8px;flex-wrap:wrap}.grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:20px}.card{padding:24px;background:white;border:1px solid var(--line);border-radius:12px;cursor:pointer;transition:box-shadow .15s,transform .15s}.card:hover{box-shadow:0 8px 24px #223f6b0b;transform:translateY(-2px)}.card small{color:var(--gold);font-size:10px;letter-spacing:1.4px}.card h3{font-size:17px;font-weight:600;line-height:1.6;min-height:48px;margin:14px 0}.card p{font-size:12px;color:var(--muted)}.card-foot{display:flex;justify-content:space-between;align-items:center;font-size:11px;border-top:1px solid var(--line);padding-top:14px;color:#7c8ba2}.search{width:260px}.muted{color:var(--muted);font-size:12px;line-height:1.9}.text-button{border:0;background:transparent;padding:7px 9px;font-size:12px;color:#6c7f99}.text-button:hover{background:#edf2fa;border-color:transparent}.learning-main{max-width:1360px;padding:22px 28px 36px}.reader-top{display:flex;align-items:center;gap:18px;color:#8995a6;font-size:11px;margin:0 0 16px}.reader-top #back{padding-left:0;color:#526b8e}.reader-top>span:nth-child(2){border-left:1px solid #d9dfe8;padding-left:18px}.top-progress{margin-left:auto}.study-shell{display:grid;grid-template-columns:minmax(0,1fr) 350px;align-items:start;gap:22px}.reading-pane{background:white;border:1px solid var(--line);border-radius:13px;overflow:hidden}.chapter-heading{padding:30px 34px 20px}.chapter-kicker{font-size:10px;font-weight:650;letter-spacing:1.8px;color:#8d9aae}.chapter-heading h1{font-size:25px;line-height:1.5;letter-spacing:.3px;font-weight:650;margin:9px 0 8px}.chapter-heading p{font-size:11px;color:#8c97a6;margin:0}.reading-controls{display:flex;gap:10px;justify-content:space-between;align-items:center;padding:14px 26px;border-top:1px solid #f0f2f6;border-bottom:1px solid var(--line);background:#fcfdff;flex-wrap:wrap}.mode-tabs{display:flex;gap:3px;flex-wrap:wrap}.mode-tabs button{padding:7px 10px;border:0;background:transparent;font-size:12px;color:#7f8ba0;border-radius:6px}.mode-tabs button.active{background:#eaf0fb;color:#3466b0;font-weight:650}.type-controls{display:flex;gap:3px;align-items:center}.type-controls button{border:0;background:transparent;padding:6px;color:#7c8ba2;font-size:12px}.type-controls span{font-size:10px;color:#a0a9b7;min-width:16px;text-align:center}.reading-intro{padding:20px 34px 0;font-size:11px;color:#9ba4b2;display:flex;justify-content:space-between;align-items:center}.story{font-size:var(--size,20px);line-height:2.35;padding:18px 34px 28px;letter-spacing:.35px;word-break:normal;overflow-wrap:anywhere;color:#344153}.word{display:inline;border:0;border-radius:4px;padding:3px 5px;background:var(--word);color:#3d69a5;font-weight:620;font-size:inherit;line-height:inherit;letter-spacing:0}.word:hover,.word.selected{background:#d7e3f9;color:#234f90}.meaning{font-size:.8em;color:#7d8898;padding-right:4px;letter-spacing:0}.blank{display:inline-block;max-width:100%;width:137px;padding:5px 8px;border:1px solid #cbd8eb;background:#f8faff;border-radius:5px;font-size:.8em;line-height:1.4;color:#395985;vertical-align:baseline}.blank::placeholder{color:#93a1b8;font-size:.9em}.correct{border-color:#9cc8b4;background:#f2faf5}.wrong{border-color:#dcb1ac;background:#fdf5f3}.reader-bottom{border-top:1px solid var(--line);margin:0 34px;padding:20px 0 12px;display:flex;justify-content:space-between;align-items:center}.reader-bottom button{min-width:112px;font-size:12px;padding:10px 16px}.reader-bottom #next{background:#f4f7fc;border-color:#dce5f4;color:#3466b0}.page-count{color:#98a4b4;font-size:11px}.study-completion{padding:0 30px 23px;display:flex;justify-content:space-between;align-items:center;gap:10px;flex-wrap:wrap}.study-completion #save-status{font-size:10px;color:#9aa4b1}.study-completion .primary{font-size:12px}.answer-feedback{margin:0 34px 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.audio-dot{background:#5480bb;animation:pulse 1s infinite}.audio-status #stop{margin-left:auto;padding:3px;font-size:10px}.word-list{overflow-y:auto;max-height:calc(100dvh - 300px);min-height:240px;scrollbar-width:thin;scrollbar-color:#dde4ef transparent;position:relative;padding:1px 4px 2px}.vocab-card{border:1px solid #e9edf4;background:#fafbfe;border-radius:9px;padding:14px;margin-bottom:12px;transition:background .15s,border .15s}.vocab-card:nth-child(3n+2){background:#fafbfa}.vocab-card.selected{border-color:#a6bde2;background:#f2f6fd}.vocab-heading{display:flex;justify-content:space-between;align-items:center;gap:8px}.card-word{border:0;background:transparent;padding:0;font-size:17px;font-weight:700;color:#2d4262;text-align:left}.card-word:hover{background:transparent;color:#376ab1}.mini-actions{display:flex;gap:2px;white-space:nowrap}.icon-button{border:0;background:transparent;padding:3px 5px;border-radius:5px;font-size:11px;color:#8a9bb4;min-width:22px;min-height:26px}.icon-button:hover{color:#376ab1;background:#e8effa}.vocab-ipa{font-family:Georgia,"Times New Roman",serif;font-size:13px;color:#8e9bb0;margin:6px 0 9px;letter-spacing:.2px}.vocab-meaning{margin:0;font-size:12px;line-height:1.8;color:#586b83}.pos-badge{font-size:10px;color:#708bad;font-weight:500;display:inline-block;margin-right:4px}.example{border-top:1px solid #e8edf5;margin-top:12px;padding-top:9px}.example-label{display:flex;align-items:center;justify-content:space-between;font-size:10px;color:#95a3b8}.example-en{font-size:12px;line-height:1.8;color:#51647f;margin:5px 0}.example-en strong{font-weight:650;color:#35649f}.example-zh{font-size:11px;color:#93a0b1;line-height:1.8;margin:6px 0 0}.source-link{border:0;background:transparent;font-size:10px;color:#a0aabb;display:block;margin:5px auto 0;padding:5px}.mobile-vocabulary{display:none}.toolbar{display:flex;gap:7px;flex-wrap:wrap;margin:20px 0}.toolbar button{font-size:12px}dialog{border:1px solid var(--line);border-radius:14px;background:white;color:var(--ink);width:min(460px,calc(100vw - 32px));max-height:76vh;padding:28px;box-shadow:0 20px 70px #21345620}dialog::backdrop{background:#243b5733}dialog>.close{position:sticky;top:0;float:right;background:white;border:1px solid var(--line);border-radius:50%;width:34px;height:34px;padding:0;z-index:1;color:#72829a;font-size:15px}#modal h2{margin:12px 0 16px;font-size:24px}#modal label{display:block;margin:16px 0 6px;font-size:12px;color:var(--muted)}input,select,textarea{border:1px solid var(--line);border-radius:7px;padding:10px;background:white;color:var(--ink)}form input,form select{width:100%;margin-bottom:10px}form button{margin-top:8px}.definition{padding:16px;background:#f2f5fa;border-radius:9px;margin:16px 0;line-height:1.8}.ipa{color:var(--muted);font:16px Georgia}#toast{position:fixed;bottom:24px;left:50%;transform:translateX(-50%);background:#34465f;color:white;padding:12px 20px;border-radius:9px;display:none;z-index:100;font-size:12px;max-width:90vw;box-shadow:0 6px 22px #24364b22}.table-wrap{overflow:auto;margin:22px 0}table{border-collapse:collapse;width:100%;background:white;font-size:12px}th,td{padding:13px;text-align:left;border-bottom:1px solid var(--line)}th{color:var(--muted);font-weight:500}.panel{padding:24px;border:1px solid var(--line);border-radius:11px;background:white;margin:20px 0}.panel textarea{width:100%;min-height:220px;font:12px monospace}.empty{padding:60px;text-align:center;color:var(--muted)}#word-popover{position:fixed;z-index:40;width:420px;max-height:min(580px,calc(100dvh - 40px));background:white;border:1px solid #dbe3f0;border-radius:14px;box-shadow:0 12px 60px #304c7630;overflow:hidden;animation:appear .12s ease}.word-popover-head{height:48px;padding:10px 20px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid #edf0f5;background:white}.close-word{border:0;background:#f2f5fa;border-radius:50%;width:32px;height:32px;padding:0;font-size:23px;font-weight:300;color:#7789a0}.word-popover-scroll{padding:18px 22px 22px;overflow-y:auto;max-height:min(532px,calc(100dvh - 88px));scrollbar-width:thin}#word-popover h2{font-size:29px;margin:0 0 7px;color:#2b4262;letter-spacing:.2px}.word-primary-meaning{background:#f4f7fc;padding:12px 14px;border-radius:7px;margin:16px 0;display:flex;gap:8px;align-items:center;flex-wrap:wrap;font-size:15px}.word-primary-meaning .pos-badge{font-size:11px}.word-play-controls{display:flex;gap:7px;flex-wrap:wrap}.word-play-controls button{font-size:12px;padding:8px 12px}.usage-note{font-size:12px;line-height:1.85;color:#8090a7;margin:16px 0 12px}#word-popover .example-en{font-size:15px;line-height:1.8}#word-popover .example-zh{font-size:12px}#word-popover .example-label{font-size:11px}.more-senses{font-size:12px;line-height:1.9;margin-top:15px;color:#70849e}.more-senses summary{cursor:pointer;color:#8a9ab0;font-size:11px}.english-explanation{font-style:italic}.mobile-word-list .vocab-card{margin:12px 0}.sheet-heading{padding-bottom:10px;border-bottom:1px solid var(--line)}[hidden]{display:none!important}@keyframes pulse{50%{opacity:.3}}@keyframes appear{from{opacity:0;transform:translateY(5px)}to{opacity:1;transform:translateY(0)}}@media(min-width:1400px){.study-shell{grid-template-columns:minmax(0,1fr) 370px}.story{padding:20px 42px 32px}.chapter-heading{padding-left:42px}}@media(max-width:1100px) and (min-width:900px){.study-shell{grid-template-columns:minmax(0,1fr) 310px;gap:16px}.learning-main{padding:20px}.chapter-heading,.story{padding-left:24px;padding-right:24px}.reading-controls{padding:12px 17px}.mode-tabs button{padding:7px 8px;font-size:11px}.mini-actions{gap:0}.icon-button{padding:3px}}@media(max-width:899px){header{height:64px;padding:0 20px}.brand small{display:none}nav{gap:0}nav button{font-size:11px;padding:7px 8px}main{padding:25px 20px}.learning-main{padding:18px 20px 28px}.study-shell{grid-template-columns:1fr}.vocabulary-pane{display:none}.mobile-vocabulary{display:inline-block}.hero{grid-template-columns:1fr}.hero-art{display:none}.grid{grid-template-columns:repeat(2,1fr)}#word-popover{left:16px!important;right:16px;bottom:18px;top:auto!important;width:auto;max-height:min(540px,67dvh);box-shadow:0 8px 80px #243c6940}.word-popover-scroll{max-height:calc(min(540px,67dvh) - 48px);padding:16px 22px 22px}#word-popover h2{font-size:27px}.reader-top{gap:12px}.reader-top>span:nth-child(2){padding-left:12px}.word-popover-head .chapter-kicker{font-size:11px}}@media(max-width:550px){header{height:auto;min-height:64px;gap:10px;padding:12px 16px;flex-wrap:wrap}.brand b{font-size:17px}.brand-mark{width:29px;height:30px;font-size:17px}nav{width:100%;justify-content:space-between;border-top:1px solid #f0f2f6;padding-top:8px;margin-top:2px}nav button{padding:6px 7px;font-size:11px}nav #account{border:0;background:transparent}main{padding:22px 16px}.learning-main{padding:14px 12px 24px}.grid{grid-template-columns:1fr}.hero{padding:25px}.hero h1{font-size:27px}.hero p{font-size:12px}.stats{gap:30px}.search{width:100%}.reader-top{font-size:10px;margin-bottom:12px}.reader-top .text-button{font-size:11px}.chapter-heading{padding:24px 21px 19px}.chapter-heading h1{font-size:22px;margin:8px 0 9px}.chapter-heading p{font-size:10px}.reading-controls{padding:11px 14px;gap:8px}.mode-tabs{gap:1px}.mode-tabs button{font-size:11px;padding:7px 8px}.type-controls{margin-left:auto}.reading-intro{padding:14px 21px 0;font-size:10px}.reading-intro .text-button{font-size:10px;padding-right:0}.story{padding:15px 21px 25px;font-size:calc(var(--size,20px) - 1px);line-height:2.3;letter-spacing:0}.meaning{font-size:.77em}.word{padding:3px 4px}.reader-bottom{margin:0 21px;padding-top:16px}.reader-bottom button{min-width:100px;font-size:11px;padding:10px 12px}.study-completion{padding:1px 15px 17px}.study-completion #save-status{font-size:9px}.mode-note{padding:0 21px}.answer-feedback{margin:0 21px 20px}.blank{width:124px;padding:6px}dialog{max-height:70dvh;padding:22px}.source-link{font-size:10px}.word-play-controls{gap:6px}.word-play-controls button{padding:9px 12px}.close-word{width:34px;height:34px}#word-popover{bottom:max(16px,env(safe-area-inset-bottom));left:12px!important;right:12px}.panel{padding:18px}.row{gap:8px}}
.paragraph-break{display:block;height:18px}
.word-audio-status{display:flex;justify-content:space-between;align-items:center;min-height:20px;margin-top:8px;font-size:10px;color:#9ca9bb}.word-audio-stop{padding:0;font-size:10px}.word{line-height:1.4}
/* Learning directory */
.directory-head{display:flex;align-items:center;justify-content:space-between;gap:36px;padding:38px 0 34px;border-bottom:1px solid #e5eaf2;margin-bottom:32px}.directory-head h1{font-size:40px;letter-spacing:-1.5px;margin:12px 0 16px}.directory-head p{color:#718098;line-height:1.8;margin:0;max-width:650px}.directory-stat{display:flex;flex-direction:column;gap:6px;text-align:right;white-space:nowrap}.directory-stat b{font-size:48px;font-weight:650;color:#254977}.directory-stat span{font-size:13px;color:#718098}.zone-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:22px}.zone-card{display:block;padding:26px 24px;border:1px solid #dce6f2;border-radius:20px;text-decoration:none;color:#234772;background:linear-gradient(140deg,#f6faff,#edf4ff);transition:transform .2s,box-shadow .2s}.zone-card:hover{transform:translateY(-4px);box-shadow:0 14px 35px #233d6810}.zone-1{background:linear-gradient(140deg,#fbf9ff,#f0edfb);color:#605095;border-color:#e6dff4}.zone-2{background:linear-gradient(140deg,#f4fbf9,#eaf5f2);color:#326e65;border-color:#d9ebe5}.zone-3{background:linear-gradient(140deg,#fffaf5,#faf0e6);color:#896239;border-color:#f0e3d5}.zone-card-top{display:flex;justify-content:space-between;font-size:16px;font-weight:600}.zone-card-top span:last-child{font-size:23px;font-weight:400;opacity:.6}.zone-code{font-size:39px;font-weight:650;letter-spacing:-1px;margin:30px 0 16px;min-height:48px}.zone-card p{font-size:13px;line-height:1.8;min-height:46px;opacity:.75}.zone-card-bottom{display:flex;flex-direction:column;gap:8px;font-size:12px;border-top:1px solid #ffffff;padding-top:16px}.zone-card-bottom span:last-child{font-weight:600}.directory-note{margin-top:36px;padding:24px 30px;border-left:3px solid #a4bbd9;background:#f5f8fc}.directory-note p{color:#768298;font-size:14px;line-height:1.8;margin-bottom:0}.directory-crumbs{display:flex;flex-wrap:wrap;gap:12px;align-items:center;color:#8b96a6;font-size:13px;margin-top:22px}.directory-crumbs a{color:#697c96;text-decoration:none}.directory-crumbs b{color:#304963;font-weight:500}.directory-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:22px;margin-top:24px}.directory-card{color:inherit;display:block;text-decoration:none;background:white;border:1px solid #e0e7f0;border-radius:18px;padding:28px;transition:border-color .2s}.directory-card:hover{border-color:#749ccf}.directory-card small{color:#78899e;font-size:12px;letter-spacing:1px}.directory-card h2{font-size:22px;line-height:1.5;margin:18px 0 12px}.directory-card p{color:#7a8797;font-size:14px;line-height:1.8;min-height:30px}.directory-card-foot{border-top:1px solid #edf0f5;padding-top:20px;display:flex;justify-content:space-between;gap:10px;font-size:13px;color:#7e8b9b}.directory-card-foot b{color:#386394;font-weight:500}.course-overview{display:flex;align-items:center;gap:22px;padding:20px 24px;background:#f0f5fb;border-radius:14px;color:#687e98;font-size:13px;flex-wrap:wrap}.course-overview progress{width:180px;height:6px;accent-color:#315f9a}.directory-section-title{font-size:23px;margin:36px 0 24px}.chapter-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:18px}.chapter-card{display:flex;align-items:center;gap:20px;padding:24px;background:white;border:1px solid #e3e9f1;border-radius:16px;color:inherit;text-decoration:none}.chapter-card:hover{border-color:#8ca9cf}.chapter-number{width:60px;height:60px;display:grid;place-items:center;border-radius:16px;background:#edf3fb;color:#6586ad;font-size:24px;flex-shrink:0}.chapter-card h3{margin:0 0 7px;font-size:18px}.chapter-card p{margin:0 0 12px;color:#8290a2;font-size:13px}.chapter-card small{color:#667b95;font-size:12px}.chapter-card>b{margin-left:auto;color:#92a4ba}.structure-tree details{border-top:1px solid #e4eaf2;padding:14px 0}.structure-tree summary{cursor:pointer;font-weight:600}.structure-tree button{padding:4px 9px;font-size:12px;margin-left:12px}.structure-course{margin:16px 0 0 16px;font-size:14px}.structure-chapter{margin:14px 0 0 16px;color:#647b96}.structure-article{font-size:12px;margin:8px 0 0 16px;color:#8894a4}
@media(max-width:1100px){.zone-grid{grid-template-columns:repeat(2,1fr)}}
@media(max-width:650px){.directory-head{padding-top:22px;gap:15px;align-items:flex-start}.directory-head h1{font-size:29px}.directory-head p{font-size:13px}.directory-stat b{font-size:33px}.directory-stat span{font-size:11px;white-space:normal;max-width:100px}.zone-grid{gap:12px}.zone-card{padding:20px 16px;border-radius:16px}.zone-code{font-size:30px;margin:22px 0 12px}.zone-card-top{font-size:14px}.zone-card p{font-size:12px}.directory-grid,.chapter-grid{grid-template-columns:1fr}.directory-card{padding:24px}.directory-card h2{font-size:20px}.directory-note{padding:20px}.chapter-card{padding:20px;gap:16px}.course-overview{gap:14px;padding:16px}.directory-crumbs{font-size:12px;gap:8px}.structure-course{margin-left:8px}.structure-chapter{margin-left:8px}}