:root {
    --primary-color: #2563EB;
    --secondary-color: #7C3AED;
    --accent-color: #F97316;
    --grad: linear-gradient(135deg, #2563EB 0%, #7C3AED 54%, #F97316 100%);
    --success-color: #34C759;
    --warning-color: #F59E0B;
    --danger-color: #FF3B30;
    --text-primary: #111827;
    --text-secondary: #6b7280;
    --bg-primary: #FBFBFD;
    --bg-secondary: #F4F5F9;
    --card: #FFFFFF;
    --border-color: #E7E8EE;
    --shadow: 0 2px 15px rgba(20, 22, 40, 0.06);
    --shadow-lg: 0 18px 50px rgba(20, 22, 40, 0.14);
    --nav-bg: rgba(255, 255, 255, 0.72);
    --chip-bg: rgba(37, 99, 235, 0.08);
    --radius: 22px;
}

:root[data-theme="dark"] {
    --text-primary: #F5F6FA;
    --text-secondary: #9a9aa6;
    --bg-primary: #0B0B0F;
    --bg-secondary: #131319;
    --card: #17171F;
    --border-color: #26262F;
    --shadow: 0 2px 15px rgba(0, 0, 0, 0.4);
    --shadow-lg: 0 18px 50px rgba(0, 0, 0, 0.55);
    --nav-bg: rgba(15, 15, 20, 0.72);
    --chip-bg: rgba(59, 130, 246, 0.16);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', Roboto, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    transition: background-color .4s ease, color .4s ease;
}

html { scroll-behavior: smooth; scroll-padding-top: 90px; overflow-x: clip; }
body { overflow-x: clip; }
img { display: block; max-width: 100%; }

a:focus-visible, button:focus-visible, summary:focus-visible, input:focus-visible {
    outline: 3px solid rgba(37, 99, 235, 0.45);
    outline-offset: 3px;
    border-radius: 6px;
}

.container { max-width: 1180px; margin: 0 auto; padding: 0 22px; }

.skip-link {
    position: absolute; left: -999px; top: 0; z-index: 2000;
    background: var(--primary-color); color: #fff; padding: 10px 16px; border-radius: 0 0 10px 0;
}
.skip-link:focus { left: 0; }

.section-title { font-size: clamp(28px, 4vw, 38px); font-weight: 800; text-align: center; letter-spacing: -0.02em; }
.section-sub { text-align: center; color: var(--text-secondary); font-size: 17px; margin-top: 12px; margin-bottom: 52px; }

.visually-hidden { position: absolute; width: 1px; height: 1px; margin: -1px; padding: 0; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }

/* ---------- Scroll progress ---------- */
.scroll-progress { position: fixed; top: 0; left: 0; right: 0; height: 3px; background: var(--grad); transform: scaleX(0); transform-origin: 0 50%; z-index: 1200; pointer-events: none; }

/* ---------- Navbar ---------- */
.navbar {
    position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
    background: var(--nav-bg);
    backdrop-filter: saturate(180%) blur(18px);
    -webkit-backdrop-filter: saturate(180%) blur(18px);
    border-bottom: 1px solid transparent;
    padding: 12px 0;
    transition: border-color .3s, box-shadow .3s, background .4s;
}
.navbar.scrolled { border-bottom-color: var(--border-color); box-shadow: 0 6px 24px rgba(20,22,40,.06); }
.navbar .container { display: flex; justify-content: space-between; align-items: center; }
.nav-brand { display: flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 700; text-decoration: none; color: var(--text-primary); }
.brand-icon { display: inline-flex; filter: drop-shadow(0 4px 10px rgba(124,58,237,.35)); }
.brand-icon svg { display: block; border-radius: 9px; }
.nav-menu { display: flex; align-items: center; gap: 22px; }
.nav-link { text-decoration: none; color: var(--text-secondary); font-weight: 500; font-size: 15px; transition: color .25s; }
.nav-link:hover { color: var(--primary-color); }
.icon-btn, .lang-switch {
    background: var(--bg-secondary); color: var(--text-primary); border: 1px solid var(--border-color);
    border-radius: 999px; cursor: pointer; font-weight: 600; transition: all .25s; display: inline-flex; align-items: center; justify-content: center;
}
.icon-btn { width: 38px; height: 38px; }
.lang-switch { padding: 8px 15px; font-size: 14px; }
.icon-btn:hover, .lang-switch:hover { border-color: var(--primary-color); color: var(--primary-color); }
.icon-btn .i-moon { display: none; }
:root[data-theme="dark"] .icon-btn .i-sun { display: none; }
:root[data-theme="dark"] .icon-btn .i-moon { display: block; }

/* ---------- Buttons ---------- */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 14px 26px; border-radius: 999px; text-decoration: none; font-weight: 600; font-size: 16px; transition: transform .2s, box-shadow .2s, background .25s; white-space: nowrap; border: none; cursor: pointer; }
.btn-sm { padding: 9px 18px; font-size: 14px; }
.btn-primary { background: var(--grad); color: #fff; box-shadow: 0 8px 22px rgba(37,99,235,.32); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(37,99,235,.42); }
.btn-secondary { background: var(--bg-secondary); color: var(--text-primary); border: 1px solid var(--border-color); }
.btn-secondary:hover { transform: translateY(-2px); border-color: var(--primary-color); color: var(--primary-color); }
.nav-cta { box-shadow: 0 6px 16px rgba(37,99,235,.3); }
.apple-icon { margin-right: 2px; }

/* App Store badge (self-contained, no external asset) */
.appstore-btn { display: inline-flex; align-items: center; gap: 12px; background: #000; color: #fff; text-decoration: none; padding: 11px 22px; border-radius: 14px; border: 1px solid rgba(255,255,255,.14); box-shadow: 0 10px 30px rgba(0,0,0,.28); transition: transform .2s, box-shadow .2s; }
.appstore-btn:hover { transform: translateY(-2px); box-shadow: 0 16px 40px rgba(0,0,0,.36); }
.appstore-btn svg { width: 30px; height: 30px; flex-shrink: 0; }
.appstore-txt { display: flex; flex-direction: column; align-items: flex-start; line-height: 1.15; }
.appstore-txt .small { font-size: 11px; opacity: .92; font-weight: 400; }
.appstore-txt .big { font-size: 19px; font-weight: 600; letter-spacing: -0.3px; }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 140px 0 90px; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; z-index: 0; background:
    radial-gradient(58% 52% at 84% 6%, rgba(249,115,22,.16), transparent 60%),
    radial-gradient(60% 55% at 78% 30%, rgba(124,58,237,.18), transparent 60%),
    radial-gradient(55% 50% at 6% 24%, rgba(37,99,235,.16), transparent 60%); }
.hero .container { position: relative; z-index: 1; display: grid; grid-template-columns: 1.05fr 1fr; gap: 56px; align-items: center; }
.eyebrow { display: inline-block; font-size: 13px; font-weight: 700; letter-spacing: .04em; color: var(--primary-color); background: var(--chip-bg); padding: 7px 14px; border-radius: 999px; margin-bottom: 20px; }
.eyebrow.sm { display: table; margin: 0 auto 14px; font-size: 12px; letter-spacing: .1em; padding: 6px 12px; }
.hero-title { font-size: clamp(38px, 5.4vw, 60px); font-weight: 800; line-height: 1.08; letter-spacing: -0.03em; margin-bottom: 18px; background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; text-wrap: balance; }
.hero-subtitle { font-size: 19px; color: var(--text-secondary); margin-bottom: 34px; max-width: 36ch; }
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; align-items: center; }
.hero-trust { list-style: none; display: flex; flex-wrap: wrap; gap: 10px 20px; margin-top: 30px; }
.hero-trust li { font-size: 14px; color: var(--text-secondary); font-weight: 500; }

/* ---------- Hero signature: live fill-light demo ---------- */
.hero-visual { position: relative; display: flex; justify-content: center; }
.light-demo { position: relative; width: 320px; max-width: 82vw; aspect-ratio: 9 / 19.5; display: flex; flex-direction: column; overflow: hidden; background: var(--card); border: 1px solid var(--border-color); border-radius: 42px; padding: 16px 16px 20px; box-shadow: var(--shadow-lg); }
.device-notch { position: absolute; top: 13px; left: 50%; transform: translateX(-50%); width: 92px; height: 22px; background: #0b0b0f; border-radius: 999px; z-index: 3; }
.ld-screen { position: relative; flex: 1; min-height: 0; border-radius: 30px; overflow: hidden; margin-top: 6px; display: flex; align-items: flex-start; justify-content: space-between; padding: 18px; background: #12141c; transition: background .5s ease; }
.ld-glow { position: absolute; top: 50%; left: 50%; width: 220px; height: 220px; transform: translate(-50%, -50%); border-radius: 50%; filter: blur(6px); background: #ffd9a8; box-shadow: 0 0 90px 40px rgba(255,255,255,.25); transition: background .5s ease, box-shadow .5s ease; }
.ld-readout { position: relative; z-index: 2; display: flex; flex-direction: column; gap: 2px; color: #fff; text-shadow: 0 1px 6px rgba(0,0,0,.35); }
.ld-kelvin { font-size: 26px; font-weight: 800; letter-spacing: -0.02em; }
.ld-scene { font-size: 13px; font-weight: 600; opacity: .9; }
.ld-badge { position: relative; z-index: 2; font-size: 11px; font-weight: 700; color: #fff; background: rgba(0,0,0,.28); backdrop-filter: blur(6px); border: 1px solid rgba(255,255,255,.28); padding: 6px 10px; border-radius: 999px; }
.ld-controls { padding: 16px 6px 2px; }
.ld-scenes { display: flex; gap: 8px; margin-bottom: 16px; }
.ld-chip { flex: 1; padding: 9px 6px; border-radius: 12px; border: 1px solid var(--border-color); background: var(--bg-secondary); color: var(--text-secondary); font-size: 13px; font-weight: 700; cursor: pointer; transition: all .25s; }
.ld-chip:hover { border-color: var(--primary-color); color: var(--primary-color); }
.ld-chip.active { background: var(--grad); color: #fff; border-color: transparent; box-shadow: 0 6px 16px rgba(37,99,235,.3); }
.ld-slider-row { display: flex; align-items: center; gap: 12px; }
.ld-slider-row .ld-ic { flex-shrink: 0; color: var(--text-secondary); display: inline-flex; }
.ld-slider { -webkit-appearance: none; appearance: none; flex: 1; height: 10px; border-radius: 999px; outline: none; cursor: pointer; background: linear-gradient(90deg, #ff9d4d 0%, #ffd9a8 30%, #fffdf7 55%, #cfe4ff 78%, #9dc4ff 100%); }
.ld-slider::-webkit-slider-thumb { -webkit-appearance: none; appearance: none; width: 24px; height: 24px; border-radius: 50%; background: #fff; border: 3px solid var(--primary-color); box-shadow: 0 3px 10px rgba(0,0,0,.25); cursor: pointer; }
.ld-slider::-moz-range-thumb { width: 24px; height: 24px; border-radius: 50%; background: #fff; border: 3px solid var(--primary-color); box-shadow: 0 3px 10px rgba(0,0,0,.25); cursor: pointer; }
.ld-slider-caption { display: flex; justify-content: space-between; margin-top: 8px; font-size: 11.5px; font-weight: 600; color: var(--text-secondary); }
.hero-chip { position: absolute; background: var(--card); border: 1px solid var(--border-color); box-shadow: var(--shadow-lg); border-radius: 14px; padding: 10px 14px; font-size: 13px; font-weight: 700; z-index: 4; }
.chip-a { top: 12%; left: -6%; animation: float 5s ease-in-out infinite; }
.chip-b { bottom: 16%; right: -5%; animation: float 5s ease-in-out infinite .8s; }
@keyframes float { 0%,100% { transform: translateY(0); } 50% { transform: translateY(-9px); } }

/* ---------- Proof band ---------- */
.proof { padding: 22px 0; border-top: 1px solid var(--border-color); border-bottom: 1px solid var(--border-color); background: var(--bg-secondary); }
.proof-row { display: flex; align-items: center; justify-content: space-between; gap: 26px; flex-wrap: wrap; }
.proof-rating { display: flex; align-items: center; gap: 12px; }
.store-mark { display: flex; align-items: center; color: var(--text-primary); }
.store-mark svg { display: block; }
.proof-sub { display: flex; flex-direction: column; line-height: 1.25; font-size: 13px; color: var(--text-secondary); }
.proof-sub strong { color: var(--text-primary); font-size: 15px; }
.proof-stats { display: flex; gap: 34px; flex-wrap: wrap; }
.stat { display: flex; flex-direction: column; }
.stat strong { font-size: 20px; font-weight: 800; background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.stat span { font-size: 12.5px; color: var(--text-secondary); }

/* ---------- Sections base ---------- */
.how, .who, .features, .duo, .screenshots, .tips, .privacy, .compare, .faq { padding: 88px 0; }
.features { background: var(--bg-secondary); }
.tips { background: var(--bg-secondary); }
.faq { background: var(--bg-secondary); }

/* How it works */
.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 26px; }
.step { position: relative; background: var(--card); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 34px 26px; text-align: left; box-shadow: var(--shadow); }
.step-badge { position: absolute; top: -16px; left: 26px; width: 34px; height: 34px; border-radius: 50%; background: var(--grad); color: #fff; font-weight: 800; display: grid; place-items: center; box-shadow: 0 6px 16px rgba(37,99,235,.35); }
.step-ic { width: 52px; height: 52px; border-radius: 15px; background: var(--chip-bg); color: var(--primary-color); display: grid; place-items: center; margin: 8px 0 16px; }
.step h3 { font-size: 20px; margin-bottom: 8px; }
.step p { color: var(--text-secondary); font-size: 15px; }
.steps .step:not(:last-child)::after { content: ""; position: absolute; top: 50%; right: -18px; width: 20px; height: 2px; background: var(--border-color); }

/* Features */
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); gap: 24px; }
.feature-card { background: var(--card); border: 1px solid var(--border-color); padding: 32px; border-radius: var(--radius); transition: transform .3s, box-shadow .3s, border-color .3s; }
.feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: transparent; }
.feature-icon { width: 54px; height: 54px; border-radius: 15px; background: var(--chip-bg); color: var(--primary-color); display: grid; place-items: center; margin-bottom: 20px; }
.feature-card:hover .feature-icon { background: var(--grad); color: #fff; }
.feature-card h3 { font-size: 20px; margin-bottom: 10px; }
.feature-card p { color: var(--text-secondary); font-size: 15px; }

/* ---------- Who lights with it ---------- */
.who-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.who-card { display: flex; flex-direction: column; background: var(--card); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 28px 24px; box-shadow: var(--shadow); transition: transform .3s, box-shadow .3s, border-color .3s; }
.who-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: transparent; }
.who-ic { width: 48px; height: 48px; border-radius: 14px; background: var(--chip-bg); color: var(--primary-color); display: grid; place-items: center; margin-bottom: 16px; }
.who-card:hover .who-ic { background: var(--grad); color: #fff; }
.who-card h3 { font-size: 17px; margin-bottom: 8px; }
.who-card p { color: var(--text-secondary); font-size: 14px; flex: 1; }
.who-tag { align-self: flex-start; margin-top: 16px; font-size: 12px; font-weight: 700; color: var(--primary-color); background: var(--chip-bg); padding: 5px 11px; border-radius: 999px; }

/* ---------- Dual-color lab ---------- */
.duo-wrap { display: grid; grid-template-columns: auto 1fr; gap: 54px; align-items: center; max-width: 860px; margin: 0 auto; }
.duo-stage { position: relative; width: 250px; max-width: 76vw; aspect-ratio: 9 / 18.5; background: var(--card); border: 1px solid var(--border-color); border-radius: 38px; padding: 12px; box-shadow: var(--shadow-lg); margin: 0 auto; transition: box-shadow .5s ease; }
.duo-stage .device-notch { width: 72px; height: 18px; top: 17px; }
.duo-screen { position: relative; height: 100%; border-radius: 28px; overflow: hidden; display: flex; flex-direction: column; background: #12141c; }
.duo-half { flex: 1; transition: background .5s ease; }
.duo-seam { position: absolute; top: 50%; left: -8px; right: -8px; height: 64px; transform: translateY(-50%); filter: blur(12px); opacity: .9; pointer-events: none; transition: background .5s ease; }
.duo-subject { position: absolute; left: 50%; bottom: 8%; transform: translateX(-50%); z-index: 2; filter: drop-shadow(0 4px 14px rgba(0,0,0,.3)); }
.duo-subject svg { display: block; }
.duo-badge { position: absolute; top: 16px; left: 16px; z-index: 3; }
.duo-controls { max-width: 460px; }
.duo-row { margin-bottom: 24px; }
.duo-row:last-child { margin-bottom: 0; }
.duo-label { display: block; font-size: 13px; font-weight: 700; color: var(--text-secondary); letter-spacing: .02em; margin-bottom: 10px; }
.duo-swatches { display: flex; gap: 12px; flex-wrap: wrap; }
.duo-swatch { width: 40px; height: 40px; border-radius: 50%; border: 2px solid var(--border-color); background: var(--sw); cursor: pointer; padding: 0; transition: transform .2s, box-shadow .2s, border-color .2s; }
.duo-swatch:hover { transform: translateY(-2px); }
.duo-swatch.active { border-color: var(--primary-color); box-shadow: 0 0 0 3px var(--chip-bg), 0 6px 14px rgba(0,0,0,.18); }
.duo-combos { display: flex; gap: 10px; flex-wrap: wrap; }
.duo-combo { padding: 9px 16px; border-radius: 12px; border: 1px solid var(--border-color); background: var(--bg-secondary); color: var(--text-secondary); font-size: 13px; font-weight: 700; cursor: pointer; transition: all .25s; }
.duo-combo:hover { border-color: var(--primary-color); color: var(--primary-color); }
.duo-combo.active { background: var(--grad); color: #fff; border-color: transparent; box-shadow: 0 6px 16px rgba(37,99,235,.3); }

/* ---------- Screenshots gallery ---------- */
.gallery { position: relative; }
.gal-track { display: flex; gap: 30px; overflow-x: auto; padding: 10px 4px 24px; scroll-snap-type: x mandatory; scrollbar-width: none; }
.gal-track::-webkit-scrollbar { display: none; }
.shot { flex: 0 0 auto; scroll-snap-align: center; text-align: center; }
.phone { width: 260px; max-width: 70vw; border-radius: 34px; padding: 10px; background: linear-gradient(160deg, #2a2a33, #0e0e12); box-shadow: var(--shadow-lg); cursor: zoom-in; }
.phone img { width: 100%; height: auto; border-radius: 26px; display: block; }
.shot figcaption { margin-top: 16px; font-weight: 600; color: var(--text-secondary); font-size: 15px; }
.gal-arrow { position: absolute; top: 42%; transform: translateY(-50%); width: 46px; height: 46px; border-radius: 50%; border: 1px solid var(--border-color); background: var(--card); color: var(--text-primary); font-size: 24px; line-height: 1; cursor: pointer; box-shadow: var(--shadow); z-index: 2; transition: all .2s; }
.gal-arrow:hover { background: var(--primary-color); color: #fff; border-color: var(--primary-color); }
.gal-arrow.prev { left: -8px; } .gal-arrow.next { right: -8px; }
.gal-dots { display: flex; justify-content: center; gap: 8px; margin-top: 6px; }
.gal-dots button { width: 8px; height: 8px; border-radius: 999px; border: none; background: var(--border-color); cursor: pointer; padding: 0; transition: all .25s; }
.gal-dots button.active { width: 24px; background: var(--primary-color); }

/* Lightbox */
.lightbox { position: fixed; inset: 0; z-index: 3000; background: rgba(0,0,0,.86); display: flex; align-items: center; justify-content: center; opacity: 0; pointer-events: none; transition: opacity .25s; padding: 24px; }
.lightbox.open { opacity: 1; pointer-events: auto; }
.lightbox img { max-width: 92vw; max-height: 88vh; border-radius: 22px; box-shadow: 0 30px 80px rgba(0,0,0,.6); }
.lightbox-close { position: absolute; top: 20px; right: 24px; width: 44px; height: 44px; border-radius: 50%; border: none; background: rgba(255,255,255,.14); color: #fff; font-size: 24px; cursor: pointer; }

/* ---------- Lighting playbook ---------- */
.tips-scroller { position: relative; }
.tips-track { display: flex; gap: 20px; overflow-x: auto; padding: 10px 40px 20px; scroll-snap-type: x mandatory; scrollbar-width: none; }
@media (max-width: 480px) { .tips-track { padding-left: 4px; padding-right: 4px; } }
.tips-track::-webkit-scrollbar { display: none; }
.tip-card { position: relative; flex: 0 0 300px; scroll-snap-align: center; background: var(--card); border: 1px solid var(--border-color); border-radius: var(--radius); padding: 26px 24px; box-shadow: var(--shadow); overflow: hidden; }
.tip-num { position: absolute; top: 10px; right: 18px; font-size: 56px; font-weight: 800; line-height: 1; background: var(--grad); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; opacity: .18; pointer-events: none; }
.tip-ic { width: 46px; height: 46px; border-radius: 13px; background: var(--chip-bg); color: var(--primary-color); display: grid; place-items: center; margin-bottom: 16px; }
.tip-card h3 { font-size: 17px; margin-bottom: 8px; }
.tip-card p { color: var(--text-secondary); font-size: 14px; }
.tip-k { display: inline-flex; align-items: center; gap: 6px; margin-top: 14px; margin-right: 8px; font-size: 12px; font-weight: 700; padding: 4px 11px; border-radius: 999px; border: 1px solid var(--border-color); background: var(--bg-primary); color: var(--text-secondary); }
.tip-k::before { content: ""; width: 8px; height: 8px; border-radius: 50%; }
.tip-k.warm::before { background: #ff9d4d; }
.tip-k.cool::before { background: #9dc4ff; }

/* ---------- Privacy ---------- */
.privacy-card { background: var(--grad); color: #fff; border-radius: 28px; padding: 48px; display: grid; grid-template-columns: 1.1fr 1fr; gap: 30px; align-items: center; box-shadow: 0 24px 60px rgba(37,99,235,.3); }
.privacy-lead h2 { font-size: clamp(24px, 3.4vw, 32px); font-weight: 800; margin-bottom: 12px; }
.privacy-lead p { opacity: .92; font-size: 16px; }
.privacy-points { list-style: none; display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.privacy-points li { display: flex; align-items: center; gap: 10px; font-weight: 600; background: rgba(255,255,255,.14); padding: 12px 14px; border-radius: 14px; font-size: 15px; }

/* ---------- Comparison table ---------- */
.table-wrap { max-width: 980px; margin: 0 auto; overflow-x: auto; background: var(--card); border: 1px solid var(--border-color); border-radius: var(--radius); box-shadow: var(--shadow); }
.cmp-table { width: 100%; min-width: 640px; border-collapse: collapse; font-size: 14.5px; }
.cmp-table th, .cmp-table td { padding: 15px 18px; text-align: left; border-bottom: 1px solid var(--border-color); vertical-align: top; }
.cmp-table thead th { font-size: 14px; font-weight: 800; color: var(--text-primary); background: var(--bg-secondary); white-space: nowrap; }
.cmp-table thead th:nth-child(2) { border-top: 3px solid var(--primary-color); }
.cmp-table th:nth-child(2), .cmp-table td:nth-child(2) { background: var(--chip-bg); }
.cmp-table tbody th { font-weight: 600; color: var(--text-primary); white-space: nowrap; }
.cmp-table td { color: var(--text-secondary); }
.cmp-table td:nth-child(2) { color: var(--text-primary); font-weight: 600; }
.cmp-table tbody tr:last-child th, .cmp-table tbody tr:last-child td { border-bottom: none; }
.cmp-table .tick { color: var(--success-color); font-weight: 800; }
.cmp-table .cmp-no { color: var(--text-secondary); opacity: .7; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 780px; margin: 0 auto; display: flex; flex-direction: column; gap: 12px; }
.faq-item { background: var(--card); border: 1px solid var(--border-color); border-radius: 16px; padding: 4px 20px; }
.faq-item summary { list-style: none; cursor: pointer; font-weight: 600; font-size: 17px; padding: 16px 0; display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; font-size: 24px; font-weight: 400; color: var(--primary-color); transition: transform .25s; }
.faq-item[open] summary::after { transform: rotate(45deg); }
.faq-item p { color: var(--text-secondary); padding: 0 0 18px; font-size: 15px; }

/* ---------- Download ---------- */
.download { padding: 96px 0; background: var(--grad); color: #fff; text-align: center; }
.download-content h2 { font-size: clamp(28px, 4vw, 40px); font-weight: 800; margin-bottom: 14px; }
.download-content p { font-size: 19px; margin-bottom: 32px; opacity: .92; }
.download .appstore-btn { background: #000; border-color: rgba(255,255,255,.2); }
.download-note { font-size: 14px; opacity: .82; margin-top: 18px; }

/* ---------- Footer ---------- */
.footer { padding: 52px 0 40px; background: var(--bg-secondary); border-top: 1px solid var(--border-color); color: var(--text-secondary); text-align: center; }
.footer-content p { margin: 5px 0; font-size: 14px; }
.footer a { color: var(--primary-color); text-decoration: none; }
.footer a:hover { text-decoration: underline; }
.footer-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 36px; text-align: left; padding-bottom: 30px; margin-bottom: 24px; border-bottom: 1px solid var(--border-color); }
.footer-col { display: flex; flex-direction: column; align-items: flex-start; gap: 10px; }
.footer-h { font-size: 15px; font-weight: 700; color: var(--text-primary); margin-bottom: 2px; }
.footer-col a { color: var(--text-secondary); font-size: 14px; transition: color .25s; }
.footer-col a:hover { color: var(--primary-color); text-decoration: none; }
.footer-about { font-size: 14px; max-width: 32ch; }
.footer-actions { display: flex; gap: 10px; margin-top: 4px; }

/* ---------- Sticky mobile CTA ---------- */
.sticky-cta { position: fixed; left: 12px; right: 12px; bottom: 12px; z-index: 900; display: none; align-items: center; justify-content: space-between; gap: 12px; background: var(--nav-bg); backdrop-filter: blur(18px); -webkit-backdrop-filter: blur(18px); border: 1px solid var(--border-color); border-radius: 18px; padding: 10px 12px; box-shadow: var(--shadow-lg); transform: translateY(140%); transition: transform .35s; }
.sticky-cta.show { transform: translateY(0); }
.sticky-app { display: flex; align-items: center; gap: 10px; }
.sticky-txt { display: flex; flex-direction: column; line-height: 1.2; }
.sticky-txt strong { font-size: 15px; }
.sticky-txt span { font-size: 12px; color: var(--text-secondary); }

/* ---------- Reveal ---------- */
.reveal { opacity: 0; transform: translateY(28px); transition: opacity .6s ease-out, transform .6s ease-out; }
.reveal.in { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
    .steps { grid-template-columns: 1fr; gap: 30px; }
    .steps .step:not(:last-child)::after { display: none; }
    .privacy-card { grid-template-columns: 1fr; padding: 36px; }
    .who-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 820px) {
    .duo-wrap { grid-template-columns: 1fr; gap: 40px; }
    .duo-controls { max-width: 460px; margin: 0 auto; }
    .duo-swatches, .duo-combos { justify-content: center; }
    .duo-label { text-align: center; }
    .nav-menu .nav-link { display: none; }
    .hero .container { grid-template-columns: 1fr; gap: 44px; text-align: center; }
    .hero-content { display: flex; flex-direction: column; align-items: center; }
    .hero-subtitle { max-width: 42ch; }
    .hero-buttons, .hero-trust { justify-content: center; }
    .hero-visual { order: -1; }
    .chip-a { left: 2%; } .chip-b { right: 2%; }
    .proof-row { justify-content: center; text-align: center; }
    .sticky-cta { display: flex; }
}
@media (max-width: 560px) {
    .hero-chip { display: none; }
    .who-grid { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; gap: 28px; }
    .tip-card { flex-basis: 270px; }
}
@media (max-width: 480px) {
    .container { padding: 0 16px; }
    .hero { padding: 120px 0 60px; }
    .hero-buttons { flex-direction: column; width: 100%; }
    .hero-buttons .btn, .hero-buttons .appstore-btn { width: 100%; justify-content: center; }
    .proof-stats { gap: 18px 24px; }
    .feature-card { padding: 26px; }
    .privacy-points { grid-template-columns: 1fr; }
    .gal-arrow { display: none; }
}

@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; animation: none !important; }
    .reveal { opacity: 1; transform: none; }
}

/* AI-AVATAR: floating "AI分身" assistant widget */
#aiToggle {
    position: fixed; right: 18px; bottom: 18px; z-index: 1200;
    width: 56px; height: 56px; border-radius: 50%; border: none; cursor: pointer;
    background: var(--grad); color: #fff; display: grid; place-items: center;
    box-shadow: 0 10px 26px rgba(37, 99, 235, .38), 0 3px 8px rgba(20, 22, 40, .18);
    transition: transform .2s, box-shadow .2s;
}
#aiToggle:hover { transform: translateY(-3px); box-shadow: 0 16px 34px rgba(37, 99, 235, .46), 0 5px 12px rgba(20, 22, 40, .2); }
#aiToggle svg { display: block; }

#aiPanel {
    position: fixed; right: 18px; bottom: 86px; z-index: 1200;
    width: min(370px, calc(100vw - 24px));
    max-height: min(540px, 75vh);
    display: flex; flex-direction: column;
    background: var(--card); border: 1px solid var(--border-color); border-radius: 16px;
    box-shadow: var(--shadow-lg), var(--shadow);
    overflow: hidden;
}
#aiPanel[hidden] { display: none; }

.ai-head { display: flex; align-items: center; gap: 10px; padding: 12px 14px; border-bottom: 1px solid var(--border-color); flex-shrink: 0; }
.ai-avatar { position: relative; width: 34px; height: 34px; border-radius: 50%; background: var(--grad); color: #fff; display: grid; place-items: center; flex-shrink: 0; }
.ai-presence { position: absolute; right: -1px; bottom: -1px; width: 10px; height: 10px; border-radius: 50%; background: var(--success-color); border: 2px solid var(--card); }
.ai-title { font-size: 14px; font-weight: 700; flex: 1; min-width: 0; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
#aiClose { width: 30px; height: 30px; border-radius: 50%; border: none; background: transparent; color: var(--text-secondary); font-size: 20px; line-height: 1; cursor: pointer; flex-shrink: 0; transition: background .2s, color .2s; }
#aiClose:hover { background: var(--bg-secondary); color: var(--text-primary); }

.ai-msgs { flex: 1; min-height: 140px; overflow-y: auto; padding: 14px; display: flex; flex-direction: column; gap: 9px; overscroll-behavior: contain; }
.ai-msg { max-width: 86%; padding: 9px 13px; border-radius: 14px; font-size: 14px; line-height: 1.5; overflow-wrap: break-word; white-space: pre-wrap; }
.ai-msg.bot { align-self: flex-start; background: var(--bg-secondary); color: var(--text-primary); border-bottom-left-radius: 5px; }
.ai-msg.user { align-self: flex-end; background: var(--grad); color: #fff; border-bottom-right-radius: 5px; }
.ai-typing { display: inline-flex; align-items: center; gap: 5px; padding: 13px; }
.ai-typing span { width: 7px; height: 7px; border-radius: 50%; background: var(--text-secondary); animation: aiBlink 1.2s infinite; }
.ai-typing span:nth-child(2) { animation-delay: .2s; }
.ai-typing span:nth-child(3) { animation-delay: .4s; }
@keyframes aiBlink { 0%, 60%, 100% { opacity: .35; transform: none; } 30% { opacity: 1; transform: translateY(-3px); } }

.ai-chips { display: flex; flex-wrap: wrap; gap: 7px; padding: 0 14px 10px; flex-shrink: 0; }
.ai-chips[hidden] { display: none; }
.ai-chip { background: var(--chip-bg); color: var(--primary-color); border: none; border-radius: 999px; padding: 7px 12px; font-size: 12.5px; font-weight: 600; font-family: inherit; cursor: pointer; transition: background .2s, color .2s; }
.ai-chip:hover { background: var(--primary-color); color: #fff; }

.ai-form { display: flex; gap: 8px; padding: 10px 12px; border-top: 1px solid var(--border-color); flex-shrink: 0; }
#aiInput { flex: 1; min-width: 0; background: var(--bg-secondary); border: 1px solid var(--border-color); border-radius: 999px; padding: 9px 15px; font: inherit; font-size: 14px; color: var(--text-primary); outline: none; transition: border-color .2s; }
#aiInput:focus { border-color: var(--primary-color); }
#aiInput::placeholder { color: var(--text-secondary); }
.ai-send { display: inline-flex; align-items: center; gap: 6px; background: var(--grad); color: #fff; border: none; border-radius: 999px; padding: 9px 16px; font-family: inherit; font-size: 13.5px; font-weight: 600; cursor: pointer; box-shadow: 0 5px 14px rgba(37, 99, 235, .3); transition: transform .2s, box-shadow .2s; }
.ai-send:hover { transform: translateY(-1px); box-shadow: 0 8px 18px rgba(37, 99, 235, .38); }
.ai-send:disabled { opacity: .55; cursor: default; transform: none; box-shadow: none; }
.ai-note { flex-shrink: 0; text-align: center; font-size: 11px; color: var(--text-secondary); padding: 0 12px 9px; margin: 0; }

@media (max-width: 820px) {
    /* keep clear of the sticky download bar */
    #aiToggle { bottom: 84px; }
    #aiPanel { bottom: 152px; max-height: min(480px, 62vh); }
}
@media (max-width: 560px) {
    #aiPanel { right: 10px; width: calc(100vw - 20px); }
}
@media (prefers-reduced-motion: reduce) {
    #aiToggle, .ai-send { transition: none; }
    .ai-typing span { animation: none; }
}
/* /AI-AVATAR */