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14px}.quiz-explain.good{background:var(--brand-soft);color:var(--brand-deep)}.ls-takeaways ul{list-style:none;padding:0;margin:6px 0 0;display:grid;gap:10px}.ls-takeaways li{display:flex;gap:12px;align-items:flex-start;font-size:16px;line-height:1.5}.ls-takeaways .tk{flex:none;width:22px;height:22px;border-radius:6px;background:var(--brand-soft);color:var(--brand-deep);display:grid;place-items:center;font-size:12px;font-weight:800}.lesson-bridge{margin-top:40px;display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;background:#211f1a;color:#f3efe6;border-radius:16px;padding:26px 28px}.lesson-bridge h3{font-family:var(--display);font-size:22px;margin:0 0 6px}.lesson-bridge p{color:#c7c1b4;margin:0;font-size:15px;max-width:52ch}.lesson-next{margin-top:24px;display:flex;align-items:center;gap:16px;flex-wrap:wrap}.lesson-next-card{flex:1;min-width:240px;border:1px solid var(--line);border-radius:14px;padding:18px;background:var(--card)}.lesson-next-card h3{font-family:var(--body);font-weight:700;font-size:17px;margin:8px 0 6px}.lesson-next-card p{color:var(--ink-2);font-size:14px;margin:0 0 12px}.tutor{display:flex;flex-direction:column;max-height:calc(100vh - 108px);border:1px solid var(--line);border-radius:16px;background:var(--card);box-shadow:var(--shadow);overflow:hidden}.tutor-head{display:flex;gap:12px;align-items:center;padding:16px 18px;border-bottom:1px solid var(--line);background:linear-gradient(180deg,var(--brand-soft),var(--paper-2))}.tutor-avatar{position:relative;flex:none;width:40px;height:40px;border-radius:12px;background:var(--brand-deep);color:#fff;display:grid;place-items:center;box-shadow:var(--shadow-sm)}.tutor-avatar svg{width:22px;height:22px}.tutor-avatar-dot{position:absolute;right:-2px;bottom:-2px;width:11px;height:11px;border-radius:50%;background:#3ddc84;border:2px solid var(--card)}.tutor-headtext{min-width:0}.tutor-title{display:flex;align-items:center;gap:8px;font-family:var(--display);font-weight:700;font-size:18px}.tutor-ai{font-family:var(--body);font-size:10px;font-weight:700;letter-spacing:.08em;color:var(--brand-deep);background:#fff;border:1px solid #d5e7da;padding:1px 6px;border-radius:5px}.tutor-sub{font-size:12.5px;line-height:1.4;color:var(--ink-2);margin-top:3px}.tutor-body{flex:1;overflow-y:auto;padding:16px;display:flex;flex-direction:column;gap:10px;min-height:240px}.tutor-empty{display:flex;flex-direction:column;gap:12px}.tutor-chips{display:flex;flex-direction:column;gap:8px}.tutor-chip{text-align:left;font:inherit;font-size:13.5px;padding:10px 13px;border:1px solid var(--line);border-radius:10px;background:var(--paper);color:var(--ink);cursor:pointer;transition:border-color .12s,background .12s}.tutor-chip:hover{border-color:var(--brand);background:var(--brand-soft)}.tutor-msg{font-size:14px;line-height:1.55;padding:11px 14px;border-radius:13px;max-width:88%;white-space:pre-wrap}.tutor-msg.user{align-self:flex-end;background:var(--brand-deep);color:#fff;border-bottom-right-radius:4px}.tutor-msg.assistant{align-self:flex-start;background:var(--paper-2);color:var(--ink);border-bottom-left-radius:4px}.tutor-welcome{max-width:100%}.tutor-thinking{display:flex;align-items:center;gap:8px;color:var(--ink-2)}.tutor-input{display:flex;align-items:center;gap:8px;padding:12px 16px;border-top:1px solid var(--line)}.tutor-input .input{flex:1;height:44px}.tutor-input .btn{height:44px;padding:0 18px}.tutor-note{padding:0 16px 12px;font-size:11px;line-height:1.4;color:var(--ink-2)}@media (max-width: 900px){.lesson{grid-template-columns:1fr}.lesson-side{position:static}.tutor{max-height:none}}@media (max-width: 780px){.hero-grid{grid-template-columns:1fr}.demo{margin-top:8px}.pillars{grid-template-columns:1fr}}