:root{--blue:#2563eb;--blue-dark:#1d4ed8;--green:#16a34a;--red:#dc2626;--yellow:#d97706;--bg:#f1f5f9;--card:#fff;--text:#1e293b;--muted:#64748b;--border:#cbd5e1}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}html{background:var(--bg);min-width:320px}body{background:var(--bg);min-height:100vh;color:var(--text);margin:0;font-family:-apple-system,BlinkMacSystemFont,HarmonyOS Sans SC,PingFang SC,Microsoft YaHei,sans-serif;font-size:17px}button,input{font:inherit}button,label,input{touch-action:manipulation}.app{width:min(100%,1120px);min-height:100vh;padding:max(18px, env(safe-area-inset-top)) max(18px, env(safe-area-inset-right)) max(28px, env(safe-area-inset-bottom)) max(18px, env(safe-area-inset-left));margin:0 auto}.app>div:not(.page-home)>h1,.app>div:not(.page-home)>.card,.app>div:not(.page-home)>.btn{width:min(100%,840px);margin-left:auto;margin-right:auto}.learning-nav{width:min(100%,840px);margin:0 auto 10px}.back-home{min-height:48px;color:var(--blue-dark);border:1px solid var(--border);cursor:pointer;background:0 0;border-radius:12px;padding:9px 14px;font-weight:700}.back-home:hover{background:#2563eb14}.back-home:active{transform:translateY(1px)}.card{background:var(--card);border:1px solid #94a3b838;border-radius:18px;margin-bottom:18px;padding:clamp(20px,3vw,30px);box-shadow:0 4px 18px #0f172a0f}h1{margin:8px 0 18px;font-size:clamp(26px,3vw,34px);line-height:1.25}p,li{line-height:1.65}.muted{color:var(--muted);font-size:15px}.page-heading{justify-content:space-between;align-items:center;gap:18px;margin-bottom:18px;display:flex}.page-heading h1{margin-bottom:0}.eyebrow{color:var(--blue);letter-spacing:.08em;margin:0 0 4px;font-size:14px;font-weight:700}.section-label{margin:12px 0;font-weight:700}.text-link{min-height:48px;color:var(--blue);border:1px solid var(--border);cursor:pointer;white-space:nowrap;background:0 0;border-radius:12px;padding:8px 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12px;font-weight:700}.date-button:disabled{color:#94a3b8;cursor:not-allowed;background:#f8fafc;border-color:#e2e8f0}.unlock-note{color:var(--yellow);text-align:center;margin:0 0 16px;font-size:14px}.completion-banner{color:#166534;background:#f0fdf4;border:1px solid #bbf7d0;border-radius:12px;margin:12px 0;padding:12px 14px;font-weight:700}.progress-item{margin:18px 0 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