:root{--ink:#183d45;--teal:#2d8b80;--lime:#d8f56c;--bg:#f4f7f6;--line:#dce7e3;--muted:#718686;--card:#fff;--danger:#a34d37}*{box-sizing:border-box}body{margin:0;background:var(--bg);color:#203a3f;font-family:Arial,"PingFang SC","Microsoft YaHei",sans-serif}button,input,textarea{font:inherit}button{cursor:pointer}button:disabled{cursor:not-allowed;opacity:.55}.hidden{display:none!important}.login-shell{min-height:100vh;display:grid;place-items:center;padding:24px;background:radial-gradient(circle at 15% 15%,#e5f3ed,transparent 35%),var(--bg)}.login-card{width:min(440px,100%);padding:42px;border:1px solid var(--line);border-radius:30px;background:rgba(255,255,255,.9);box-shadow:0 24px 80px #315d5c18}.brand-mark{width:54px;height:54px;display:grid;place-items:center;border-radius:17px;background:var(--ink);color:var(--lime);font-size:29px;font-weight:bold}.brand-mark.small{width:38px;height:38px;border-radius:12px;font-size:20px}.eyebrow{margin:0 0 10px;color:var(--teal);font-size:11px;font-weight:800;letter-spacing:.18em}.login-card h1{margin:0 0 14px;color:var(--ink);font-size:42px;line-height:1.06;letter-spacing:-.07em}.muted{color:var(--muted);font-size:13px;line-height:1.7}.stack-form{display:grid;gap:14px}.stack-form label,.form-grid label{display:grid;gap:7px;color:#557075;font-size:13px;font-weight:700}.stack-form input,.form-grid input,.sentence-card input,.sentence-card textarea{width:100%;padding:12px 13px;border:1px solid var(--line);border-radius:12px;background:#fbfdfc;color:#26454a;outline:none}.stack-form input:focus,.form-grid input:focus,.sentence-card input:focus,.sentence-card textarea:focus{border-color:#65a99c;box-shadow:0 0 0 4px #d9f0e8}.primary-btn,.secondary-btn,.text-btn{border:0;border-radius:13px;padding:12px 16px;font-size:13px;font-weight:800}.primary-btn{background:var(--lime);color:var(--ink);box-shadow:0 8px 18px #b7d74738}.secondary-btn{border:1px solid #b9d8cb;background:#eef8f3;color:#24565b}.text-btn{padding:7px 10px;background:transparent;color:var(--muted)}.error-text{min-height:18px;margin:0;color:var(--danger);font-size:12px}.topbar{height:72px;display:flex;align-items:center;justify-content:space-between;padding:0 max(24px,calc((100% - 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28px,680px);padding-top:24px}.topbar{padding:0 15px}.tabs{padding:0 10px;overflow:auto}.tab{padding:14px 12px;white-space:nowrap}.page-heading,.section-head,.editor-footer{align-items:flex-start;flex-direction:column}.book-meta,.sentence-fields{grid-template-columns:1fr}.row-actions{width:100%}.row-actions button{flex:1}.login-card{padding:30px}.login-card h1{font-size:36px}.audio-row{align-items:stretch;flex-direction:column}.audio-row audio{width:100%}}