:root{font-family:-apple-system,BlinkMacSystemFont,PingFang SC,Microsoft YaHei,Noto Sans SC,Helvetica Neue,Arial,sans-serif;color:#17324d;background:radial-gradient(circle at top,rgba(98,157,238,.12),transparent 30%),linear-gradient(180deg,#edf2f7,#e6ecf3);line-height:1.5;font-weight:400;font-synthesis:none;text-rendering:optimizeLegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}*{box-sizing:border-box}html,body,#root{min-height:100%;margin:0}body{min-height:100vh}button{font:inherit}.page-shell{min-height:100vh;display:flex;align-items:center;justify-content:center;padding:28px 16px}.phone-frame{width:100%;max-width:390px;background:linear-gradient(180deg,#f5f9ff,#eef4fb);border-radius:34px;padding:10px;box-shadow:0 26px 64px #2c4d6e29,0 10px 24px #2c4d6e1f}.phone-screen{min-height:780px;max-height:min(90vh,860px);background:#fff;border-radius:26px;overflow:hidden;display:flex;flex-direction:column;position:relative}.app-header{background:linear-gradient(180deg,#f7fbff,#edf5ff);border-bottom:1px solid #dde8f3;padding:10px 16px 14px}.status-bar{display:flex;align-items:center;justify-content:space-between;font-size:13px;font-weight:600;color:#35526f;margin-bottom:12px}.status-icons{display:flex;gap:6px;align-items:center}.signal,.wifi,.battery{display:inline-block;border-radius:999px;background:#35526f}.signal,.wifi{width:14px;height:7px;opacity:.88}.battery{width:20px;height:10px}.title-bar h1{margin:0;font-size:20px;color:#143d63}.content-area{flex:1;overflow-y:auto;padding:18px 14px 126px;background:linear-gradient(180deg,#f2f7fdb3,#ffffff1f),#fff}.screen-fill{min-height:100%;display:flex;flex-direction:column}.screen-fill-centered{justify-content:center}.screen-fill-bottom{justify-content:flex-end}.screen-fill-between{justify-content:space-between}.message-stack{display:flex;flex-direction:column}.action-zone{margin-top:18px}.footer-bar{position:absolute;left:0;right:0;bottom:0;background:#fffffff5;border-top:1px solid #e2ebf5;padding:12px 14px calc(14px + env(safe-area-inset-bottom));-webkit-backdrop-filter:blur(16px);backdrop-filter:blur(16px)}.button-stack{display:flex;flex-direction:column;gap:10px}.action-button{width:100%;border:none;border-radius:16px;padding:14px 18px;background:linear-gradient(180deg,#2d8eff,#1677ff);color:#fff;font-weight:600;font-size:16px;box-shadow:0 10px 20px #1b76eb38;transition:transform .18s ease,box-shadow .18s ease,opacity .18s ease}.action-button:active{transform:translateY(1px)}.action-button:disabled{opacity:.55;box-shadow:none}.action-button-secondary{background:#eef5ff;color:#1d5ea8;box-shadow:inset 0 0 0 1px #d0e3fb}.intro-card,.section-card,.history-summary-card,.record-card,.hint-card,.empty-card{background:#fff;border-radius:22px;border:1px solid #e4edf7;box-shadow:0 12px 28px #2b527e14}.intro-card{padding:24px 20px}.intro-card h1{margin:10px 0 12px;font-size:30px;color:#10395f}.intro-card p{margin:0 0 12px;color:#4f6983}.intro-badge{display:inline-flex;padding:6px 12px;border-radius:999px;background:#e8f3ff;color:#1b68c9;font-size:12px;font-weight:700;letter-spacing:.04em}.message-row{display:flex;align-items:flex-end;gap:10px;margin-bottom:14px}.message-row-subtle{margin-top:-2px}.message-row-user{justify-content:flex-end}.avatar{width:34px;height:34px;border-radius:50%;background:linear-gradient(180deg,#dceefe,#c4defc);color:#2064af;display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:700;flex-shrink:0}.avatar-user{background:linear-gradient(180deg,#434a54,#242a33);color:#fff;position:relative;overflow:hidden}.user-head{position:absolute;top:7px;left:50%;width:9px;height:9px;margin-left:-4.5px;border-radius:50%;background:currentColor}.user-shoulders{position:absolute;left:50%;bottom:7px;width:18px;height:10px;margin-left:-9px;border-radius:10px 10px 6px 6px;background:currentColor}.bubble{max-width:84%;padding:14px 15px;border-radius:18px;font-size:14px;box-shadow:0 8px 20px #39628f14}.bubble-system{background:#f2f5f8;color:#31485f;border-top-left-radius:8px}.bubble-subtle{background:#f6f9fc}.bubble-user{background:linear-gradient(180deg,#2490ff,#1677ff);color:#fff;border-top-right-radius:8px}.selection-card,.option-card{width:100%;border:1.5px solid #d9e8f8;background:#fff;border-radius:20px;padding:16px;text-align:left;color:#254767;box-shadow:0 10px 18px #2a54830f;margin-bottom:12px}.selection-card-active,.option-card-active{border-color:#2385ff;background:#eef6ff}.selection-card-label{display:block;font-size:12px;color:#1f74d8;font-weight:700;margin-bottom:8px}.history-summary-card,.section-card,.hint-card,.empty-card{padding:14px 16px;margin-bottom:14px}.history-summary-row{display:flex;gap:10px;align-items:center;color:#45627d;font-size:14px}.history-summary-row+.history-summary-row{margin-top:10px}.history-dot{width:8px;height:8px;border-radius:50%;background:#2790ff;flex-shrink:0}.section-card h2{margin:0 0 8px;font-size:20px;color:#113b61}.section-card p,.hint-card,.empty-card{margin:0;color:#547089;font-size:14px}.record-list{display:grid;gap:12px}.record-card{padding:16px}.record-title{color:#1472db;font-size:13px;font-weight:700;margin-bottom:6px}.record-detail{color:#355069}.option-list{display:grid;gap:12px}.toast{position:fixed;left:50%;bottom:36px;transform:translate(-50%);background:#122841eb;color:#fff;padding:12px 16px;border-radius:14px;font-size:14px;box-shadow:0 12px 28px #12284140}.modal-overlay{position:fixed;top:0;right:0;bottom:0;left:0;background:#1b283847;display:flex;align-items:center;justify-content:center;padding:24px;z-index:20}.modal-card{width:min(100%,332px);background:#fff;border:1px solid #dfebf8;border-radius:22px;box-shadow:0 18px 42px #213d5c2e;padding:20px 18px 16px}.modal-card p{margin:0 0 16px;color:#36516c;font-size:15px;line-height:1.7}@media (max-width: 480px){.page-shell{padding:0}.phone-frame{max-width:100%;border-radius:0;padding:0;box-shadow:none;min-height:100vh}.phone-screen{min-height:100vh;max-height:none;border-radius:0}.content-area{padding-bottom:128px}}