:root{--bg: #f7f3ea;--surface: #fffdf8;--ink: #1d2721;--muted: #5b6660;--line: #e3dccd;--green: #1f4d3a;--green-2: #2f6b52;--green-soft: #e4eee8;--orange: #d9772b;--orange-ink: #9a4a0f;--orange-soft: #fbead9;--red: #a8322b;--red-soft: #f8e1de;--ok: #1f6b45;--ok-soft: #dff0e6;--radius: 14px;--shadow: 0 1px 2px rgba(31, 45, 36, .06), 0 4px 16px rgba(31, 45, 36, .05);--font: "PingFang SC", "Hiragino Sans GB", "Noto Sans CJK SC", "Source Han Sans SC", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;--font-en: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, "Times New Roman", serif;--font-ipa: "Charis SIL", "Doulos SIL", "Gentium Plus", "Lucida Sans Unicode", "Segoe UI", "Arial Unicode MS", sans-serif}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--font);font-size:17px;line-height:1.7}h1,h2,h3,h4{line-height:1.3;margin:0 0 .5em;font-weight:650}h1{font-size:1.85rem;letter-spacing:.01em}h2{font-size:1.3rem}h3{font-size:1.1rem}p{margin:0 0 .8em}a{color:var(--green-2);text-underline-offset:3px}a:hover{color:var(--green)}:focus-visible{outline:3px solid var(--orange);outline-offset:2px;border-radius:6px}[tabindex="-1"]:focus{outline:none}.wrap{max-width:1080px;margin:0 auto;padding:0 20px}.narrow{max-width:760px;margin:0 auto}.muted{color:var(--muted)}.small{font-size:.88rem}.big{font-size:1.25rem;font-weight:650}.eyebrow{color:var(--orange-ink);font-size:.9rem;font-weight:600;letter-spacing:.04em;margin-bottom:.3em}.lead{font-size:1.08rem;color:#33403a}.row-between{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap}.skip-link{position:absolute;left:-999px;top:8px;background:var(--green);color:#fff;padding:8px 14px;border-radius:8px;z-index:10}.skip-link:focus{left:8px}.site-header{background:var(--surface);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:5}.header-inner{display:flex;align-items:center;justify-content:space-between;height:60px;gap:16px}.brand{display:inline-flex;align-items:center;gap:10px;color:var(--green);font-weight:700;font-size:1.15rem;text-decoration:none;letter-spacing:.06em}.brand .dot{color:var(--orange)}.main-nav{display:flex;gap:4px}.main-nav a{padding:8px 14px;border-radius:999px;color:var(--ink);text-decoration:none;font-weight:500}.main-nav a:hover{background:var(--green-soft)}.main-nav a[aria-current=page]{background:var(--green);color:#fff}main{padding-top:28px;padding-bottom:48px;min-height:70vh}.site-footer{color:var(--muted);font-size:.85rem;padding-bottom:96px;border-top:1px solid var(--line);padding-top:16px}.notice{background:var(--orange-soft);border-bottom:1px solid #efcfaf}.notice .wrap{display:flex;justify-content:space-between;align-items:center;gap:12px;padding-top:10px;padding-bottom:10px}.banner{background:var(--orange-soft);border:1px solid #efcfaf;border-radius:10px;padding:10px 14px;margin:12px 0}.banner a{margin:0 4px}.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow);margin-bottom:18px}.grid-2{display:grid;grid-template-columns:1.3fr 1fr;gap:18px}.grid-2>.card{margin-bottom:0}.grid-2+*{margin-top:18px}.page-head{margin-bottom:20px}.btn,.choice-pill{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--green);background:var(--green);color:#fff;border-radius:10px;padding:9px 18px;font:inherit;font-weight:600;cursor:pointer;text-decoration:none;line-height:1.4}.btn:hover{background:var(--green-2);color:#fff}.btn.big{padding:12px 24px;font-size:1.05rem}.btn.small{padding:5px 12px;font-size:.88rem}.btn.ghost{background:transparent;color:var(--green)}.btn.ghost:hover{background:var(--green-soft);color:var(--green)}.btn.danger{background:var(--red);border-color:var(--red)}.btn.danger-ghost{background:transparent;color:var(--red);border-color:var(--red)}.btn:disabled,.btn[disabled]{opacity:.5;cursor:not-allowed}.btn-row{display:flex;flex-wrap:wrap;gap:10px;align-items:center;margin:12px 0}.audio-btn-wrap{display:inline-flex;flex-direction:column;gap:2px}.audio-btn{display:inline-flex;align-items:center;gap:6px;font:inherit;cursor:pointer;border-radius:999px;border:1px solid var(--green);background:var(--surface);color:var(--green);padding:7px 16px;font-weight:600}.audio-btn.primary{background:var(--green);color:#fff}.audio-btn.chip{padding:3px 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var(--line);background:var(--bg);font:inherit;cursor:pointer;color:var(--ink)}.choice-card.on{border-color:var(--green);background:var(--green-soft);box-shadow:inset 0 0 0 1px var(--green)}.choice-pill{background:var(--surface);color:var(--green)}.choice-pill.on{background:var(--green);color:#fff}.stage{margin-bottom:28px}.stage-num{color:var(--orange-ink);font-size:.95rem;margin-right:6px}.lesson-list{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.lesson-link{display:flex;gap:14px;align-items:flex-start;padding:14px 16px;background:var(--surface);border:1px solid var(--line);border-radius:12px;text-decoration:none;color:var(--ink);height:100%}.lesson-link:hover{border-color:var(--green-2)}.lesson-item.next .lesson-link{border-color:var(--orange);box-shadow:inset 0 0 0 1px 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var(--line);margin:0}.chip-row,.chunks{display:flex;flex-wrap:wrap;gap:8px;align-items:center}.mouth{margin:8px 0}.mouth svg{width:100%;max-width:420px;height:auto;display:block}.mouth figcaption{font-size:.78rem;color:var(--muted)}.m-lip{fill:#c98375}.m-inner{fill:#4a2622}.m-seam{stroke:#7a3e35;stroke-width:2}.m-teeth{fill:#fff}.m-tongue{fill:#e59a91}.m-palate{fill:none;stroke:#7d877f;stroke-width:2}.m-teeth-side{fill:#fff;stroke:#b9bfba}.m-lip-side{fill:none;stroke:#c98375;stroke-width:4;stroke-linecap:round}.m-tongue-side{fill:#e59a91;opacity:.9}.m-curl{fill:none;stroke:#b5574c;stroke-width:2}.m-dot{fill:var(--orange)}.m-arrow{stroke:var(--green-2);stroke-width:2}.m-arrowhead{fill:var(--green-2)}.m-voice{fill:none;stroke:var(--orange);stroke-width:2}.m-novoice{stroke:#9aa29d;stroke-width:2;stroke-dasharray:3 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var(--line);vertical-align:middle}.word-table th{font-size:.85rem;color:var(--muted);font-weight:600}.letter-grid{list-style:none;padding:0;display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:14px}.letter-card{margin:0}.letter-big{font-family:var(--font-en);font-size:2rem;color:var(--green);font-weight:600}.letter-sounds{list-style:none;padding:0;margin:0;display:grid;gap:6px}.letter-sounds li{display:flex;gap:10px;align-items:center}.rate-set{border:0;padding:0;margin:10px 0 0}.rate-set legend{margin-bottom:4px}.danger-zone{border-color:#eac3be}.reset-confirm label{display:flex;gap:8px;align-items:center;flex-wrap:wrap}@media(max-width:860px){.grid-2,.quick-links,.lesson-list,.phoneme-grid,.practice-grid{grid-template-columns:1fr}.pick-list{position:static}.four-steps{grid-template-columns:repeat(2,1fr)}}@media(max-width:640px){body{font-size:16px}h1{font-size:1.5rem}.welcome h1{font-size:1.7rem}.wrap{padding:0 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