/* ============================================================
   品航科技 V2 — 货代物流 AI 智能体
   极简品牌官网：纯文字力量 + 背景氛围
   ============================================================ */

/* ---------- Fonts (self-hosted) ---------- */
@font-face {
    font-family: "Alimama FangYuan Square";
    src: url("fonts/AlimamaFangYuanSquare-Light.woff2") format("woff2");
    font-weight: 200; font-style: normal; font-display: swap;
}
@font-face {
    font-family: "Alimama FangYuan Square";
    src: url("fonts/AlimamaFangYuanSquare-Regular.woff2") format("woff2");
    font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
    font-family: "Alimama FangYuan Square";
    src: url("fonts/AlimamaFangYuanSquare-Bold.woff2") format("woff2");
    font-weight: 700; font-style: normal; font-display: swap;
}
@font-face {
    font-family: "Outfit";
    src: url("fonts/Outfit-ExtraLight.woff2") format("woff2");
    font-weight: 200; font-style: normal; font-display: swap;
}
@font-face {
    font-family: "Outfit";
    src: url("fonts/Outfit-Regular.woff2") format("woff2");
    font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
    font-family: "Outfit";
    src: url("fonts/Outfit-ExtraBold.woff2") format("woff2");
    font-weight: 800; font-style: normal; font-display: swap;
}

/* ---------- Tokens ---------- */
:root {
    color-scheme: dark;
    --brand: #6ef1ff;
    --brand-deep: #4d7cff;
    --accent-deep: #7e85ff;
    --bg: #060a14;
    --surface: #0a1220;
    --surface-raised: #0e1828;
    --text: #f3f7ff;
    --text-secondary: rgba(219, 229, 255, 0.68);
    --text-muted: rgba(219, 229, 255, 0.42);
    --line: rgba(112, 169, 255, 0.12);
    --line-strong: rgba(124, 211, 255, 0.24);
    --shadow-card: 0 24px 80px rgba(0, 0, 0, 0.42), inset 0 0.5px rgba(255, 255, 255, 0.08);
    --shadow-brand: 0 24px 70px rgba(110, 241, 255, 0.16), inset 0 0.5px rgba(255, 255, 255, 0.2);
    --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
    --font-sans: "Outfit", "Alimama FangYuan Square", -apple-system, BlinkMacSystemFont,
        "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", Arial, sans-serif;
    --radius-lg: 22px;
    --radius-xl: 28px;
    --page-width: min(calc(100vw - 48px), 1120px);
    --copy-width: 720px;
    --wide-frame-width: min(calc(100vw - 48px), 1480px);
    --compact-frame-width: min(calc(100vw - 48px), 1120px);
    --section-space: clamp(104px, 11vw, 164px);
}

/* ---------- Reset ---------- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
html.lenis, html.lenis body { height: auto; }
.lenis.lenis-smooth { scroll-behavior: auto !important; }
body {
    min-height: 100vh;
    font-family: var(--font-sans);
    color: var(--text);
    background: var(--bg);
    letter-spacing: 0.008em;
    line-height: 1.7;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
    font-synthesis: none;
}
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
ul, ol { list-style: none; }

/* ---------- Boot ---------- */
.boot-cover {
    position: fixed; inset: 0; z-index: 9999;
    background: var(--bg); pointer-events: none;
    animation: boot-fade 0.6s var(--ease-out) 0.12s forwards;
}
@keyframes boot-fade { to { opacity: 0; visibility: hidden; } }

/* ---------- 滚动进度条 ---------- */
.scroll-progress {
    position: fixed;
    top: 0; left: 0;
    height: 2px;
    width: 0;
    z-index: 200;
    background: linear-gradient(90deg, var(--brand), var(--brand-deep));
    box-shadow: 0 0 8px rgba(110, 241, 255, 0.6);
    pointer-events: none;
}

/* ---------- Header（浮动胶囊，滚动两边收缩） ---------- */
.site-header {
    position: fixed;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: var(--wide-frame-width);
    min-height: 60px;
    padding: 8px 10px 8px 20px;
    border-radius: 18px;
    border: 1px solid transparent;
    background: transparent;
    transition: width 0.5s var(--ease-out), border-color 0.5s var(--ease-out),
        background 0.5s var(--ease-out), backdrop-filter 0.5s var(--ease-out),
        -webkit-backdrop-filter 0.5s var(--ease-out), box-shadow 0.5s var(--ease-out);
}
.site-header.is-scrolled {
    width: var(--compact-frame-width);
    border-color: var(--line);
    background: rgba(6, 10, 20, 0.72);
    -webkit-backdrop-filter: blur(24px) saturate(1.35);
    backdrop-filter: blur(24px) saturate(1.35);
    box-shadow: 0 18px 60px rgba(0, 0, 0, 0.32), inset 0 0.5px rgba(255, 255, 255, 0.08);
}
.brand { display: inline-flex; align-items: center; gap: 12px; }
.brand-mark {
    display: grid; place-items: center;
    width: 36px; height: 36px; border-radius: 10px;
    color: var(--brand);
    background: linear-gradient(160deg, rgba(110, 241, 255, 0.14), rgba(125, 133, 255, 0.14));
    border: 1px solid var(--line-strong);
    box-shadow: inset 0 0.5px rgba(255, 255, 255, 0.2);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text strong { font-size: 15px; font-weight: 700; letter-spacing: -0.01em; }
.brand-text em {
    font-style: normal; font-family: "Outfit", var(--font-sans);
    font-size: 9px; letter-spacing: 0.18em;
    color: var(--text-muted); text-transform: uppercase;
}
.site-nav { display: flex; align-items: center; gap: clamp(18px, 2.4vw, 34px); }
.site-nav a { position: relative; font-size: 13.5px; color: var(--text-secondary); transition: color 0.25s var(--ease-out); }
.site-nav a:hover { color: var(--text); }
.site-nav a::after {
    content: ""; position: absolute; left: 0; bottom: -6px;
    width: 0; height: 1.5px; background: var(--brand);
    transition: width 0.3s var(--ease-out);
}
.site-nav a:hover::after { width: 100%; }
.site-nav .nav-cta {
    padding: 8px 16px; border: 1px solid var(--line-strong);
    border-radius: 999px; color: var(--text);
}
.site-nav .nav-cta:hover { border-color: var(--brand); box-shadow: 0 0 22px rgba(110, 241, 255, 0.18); }
.site-nav .nav-cta::after { display: none; }

/* ---------- Hero ---------- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex; align-items: center;
    padding: 150px clamp(24px, 4vw, 48px) 110px;
    overflow: hidden;
}
.hero-backdrop { position: absolute; inset: 0; pointer-events: none; }
.hero-grid {
    position: absolute; inset: 0;
    background-image: linear-gradient(rgba(255, 255, 255, 0.018) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.018) 1px, transparent 1px);
    background-size: 56px 56px;
    mask-image: radial-gradient(circle at 50% 38%, #000 0%, transparent 74%);
    -webkit-mask-image: radial-gradient(circle at 50% 38%, #000 0%, transparent 74%);
}
.hero-glow { position: absolute; border-radius: 50%; }
.glow-a { width: 760px; height: 760px; left: 50%; top: 6%; transform: translateX(-50%) translateY(var(--parallax-a, 0px)); background: radial-gradient(circle, rgba(110, 241, 255, 0.16), rgba(110, 241, 255, 0.06) 42%, transparent 70%); }
.glow-b { width: 560px; height: 560px; right: -120px; bottom: -80px; transform: translateY(var(--parallax-b, 0px)); background: radial-gradient(circle, rgba(125, 133, 255, 0.18), rgba(125, 133, 255, 0.06) 42%, transparent 70%); }
.hero-route { position: absolute; inset: 0; width: 100%; height: 100%; }
.route-line {
    fill: none; stroke: var(--brand); stroke-width: 1.2;
    stroke-linecap: round; opacity: 0.4; stroke-dasharray: 5 8;
    animation: route-flow 26s linear infinite;
}
.route-line.dim { opacity: 0.14; animation-duration: 36s; }
@keyframes route-flow { to { stroke-dashoffset: -1000; } }

.hero-inner {
    position: relative;
    width: 100%; max-width: var(--page-width);
    margin: 0 auto;
}
.eyebrow {
    display: inline-flex; align-items: center; gap: 14px;
    font-family: "Outfit", var(--font-sans);
    font-size: 12px; letter-spacing: 0.3em; text-transform: uppercase;
    color: var(--brand); margin-bottom: 30px;
}
.eyebrow::before { content: ""; width: 30px; height: 1px; background: var(--brand); opacity: 0.7; }
.hero h1 {
    font-size: clamp(48px, 8vw, 116px);
    line-height: 1.14;
    font-weight: 700;
    letter-spacing: -0.025em;
    text-wrap: balance;
    margin-bottom: 30px;
    max-width: 11em;
}
.hero h1 .line {
    display: block;
}
.hero h1 .line-inner.brand-word {
    color: var(--brand);
}
.hero h1 .char {
    display: inline-block;
    animation: char-in 0.65s var(--ease-out) both;
    will-change: transform, opacity, filter;
}
@keyframes char-in {
    from { opacity: 0; transform: translateY(0.45em); filter: blur(8px); }
    to { opacity: 1; transform: translateY(0); filter: blur(0); }
}

/* Hero 加载 stagger 动画 */
.eyebrow,
.hero-lead,
.hero-actions {
    animation: hero-fade-up 0.85s var(--ease-out) both;
}
.eyebrow { animation-delay: 0.05s; }
.hero-lead { animation-delay: 1.0s; }
.hero-actions { animation-delay: 1.15s; }
@keyframes hero-fade-up {
    from { opacity: 0; transform: translateY(24px); }
    to { opacity: 1; transform: translateY(0); }
}
.hero-lead {
    max-width: 560px;
    font-size: clamp(16px, 1.3vw, 20px);
    line-height: 1.8;
    color: var(--text-secondary);
    margin-bottom: 44px;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }
.btn {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 15px 28px; border-radius: 999px;
    font-size: 15px; font-weight: 700; letter-spacing: -0.01em;
    cursor: pointer;
    transition: transform 0.3s var(--ease-out), box-shadow 0.3s var(--ease-out), border-color 0.3s var(--ease-out);
}
.btn-primary { color: #04121a; background: linear-gradient(120deg, var(--brand), var(--brand-deep)); box-shadow: var(--shadow-brand); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 28px 90px rgba(110, 241, 255, 0.3); }
.btn-ghost { color: var(--text); border: 1px solid var(--line-strong); background: rgba(255, 255, 255, 0.02); }
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--brand); }

/* ---------- Sections ---------- */
.section { padding: var(--section-space) clamp(24px, 4vw, 48px); }
.section-head {
    max-width: var(--copy-width);
    margin: 0 auto clamp(60px, 7vw, 92px);
}
.section-kicker {
    display: inline-flex; align-items: center; gap: 14px;
    font-family: "Outfit", var(--font-sans);
    font-size: 12px; letter-spacing: 0.28em; text-transform: uppercase;
    color: var(--brand); margin-bottom: 24px;
}
.section-kicker::before { content: ""; width: 30px; height: 1px; background: var(--brand); opacity: 0.7; }
.section-head h2,
.vision-section h2 {
    font-size: clamp(32px, 4.6vw, 60px);
    line-height: 1.08;
    font-weight: 700;
    letter-spacing: -0.02em;
    text-wrap: balance;
}
.section-sub {
    margin-top: 20px;
    font-size: clamp(16px, 1.2vw, 18px);
    line-height: 1.7;
    color: var(--text-secondary);
}

/* ---------- 数据带 ---------- */
.metrics-section { padding-top: 0; padding-bottom: clamp(80px, 9vw, 130px); }
.metrics-grid {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    border-top: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
}
.metric {
    padding: 36px 30px;
    border-right: 1px solid var(--line);
}
.metric:last-child { border-right: none; }
.metric-num {
    display: block;
    font-family: "Outfit", var(--font-sans);
    font-size: clamp(40px, 4vw, 56px);
    font-weight: 800;
    line-height: 1;
    color: var(--brand);
    margin-bottom: 14px;
    letter-spacing: -0.02em;
}
.metric-num small {
    font-size: 0.45em;
    color: var(--text-secondary);
    margin-left: 2px;
    letter-spacing: 0;
}
.metric p { font-size: 13.5px; color: var(--text-secondary); line-height: 1.5; }

/* ---------- 行业挑战 ---------- */
.pain-section h2 {
    white-space: nowrap;
    font-size: clamp(24px, 3.9vw, 50px);
}
.pain-list {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 28px;
    border-top: 1px solid var(--line);
    padding-top: 40px;
}
.pain-index {
    display: inline-block;
    font-family: "Outfit", var(--font-sans);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 0.14em;
    color: var(--brand);
    margin-bottom: 16px;
    opacity: 0.85;
}
.pain-item h3 {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 10px;
}
.pain-item p {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-secondary);
}

/* ---------- 能力卡片 ---------- */
.cap-grid {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 20px;
}
.cap-card {
    position: relative;
    padding: 36px 32px;
    border-radius: var(--radius-lg);
    border: 1px solid transparent;
    background:
        linear-gradient(var(--surface), var(--surface)) padding-box,
        linear-gradient(160deg, rgba(110, 241, 255, 0.24), rgba(125, 133, 255, 0.08) 55%, rgba(110, 241, 255, 0.12)) border-box;
    box-shadow: var(--shadow-card);
    overflow: hidden;
    transition: transform 0.4s var(--ease-out), box-shadow 0.4s var(--ease-out);
}
.cap-card::before {
    content: ""; position: absolute; inset: 0;
    background: radial-gradient(420px circle at var(--spotlight-x, 50%) var(--spotlight-y, 50%), rgba(110, 241, 255, 0.16), transparent 60%);
    opacity: var(--spotlight-opacity, 0);
    pointer-events: none;
    transition: opacity 0.24s ease;
}
.cap-card::after {
    content: ""; position: absolute; left: 0; right: 0; top: 0; height: 1px;
    background: linear-gradient(90deg, transparent, rgba(110, 241, 255, 0.7), transparent);
    opacity: 0; transition: opacity 0.45s var(--ease-out);
}
.cap-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 30px 80px rgba(0, 0, 0, 0.5), 0 0 40px rgba(110, 241, 255, 0.12);
}
.cap-card:hover::after { opacity: 1; }
.cap-index {
    position: relative; z-index: 1;
    display: inline-block;
    font-family: "Outfit", var(--font-sans);
    font-size: 13px; font-weight: 800; letter-spacing: 0.16em;
    color: var(--brand); margin-bottom: 24px; opacity: 0.9;
}
.cap-card h3 {
    position: relative; z-index: 1;
    font-size: 20px; font-weight: 700; letter-spacing: -0.01em;
    margin-bottom: 12px;
}
.cap-card p {
    position: relative; z-index: 1;
    font-size: 14.5px; line-height: 1.7; color: var(--text-secondary);
}
.cap-card.cap-wide {
    grid-column: 1 / -1;
    display: flex;
    align-items: center;
    gap: 28px;
    padding: 30px 36px;
}
.cap-card.cap-wide .cap-index {
    margin-bottom: 0;
    flex-shrink: 0;
}
.cap-card.cap-wide h3 {
    margin-bottom: 0;
    flex-shrink: 0;
}
.cap-card.cap-wide p {
    max-width: 640px;
}

/* ---------- 优势 ---------- */
.why-grid {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 18px;
}
.why-item {
    position: relative;
    padding: 30px 26px;
    border-radius: var(--radius-lg);
    background: var(--surface);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-card);
    overflow: hidden;
    isolation: isolate;
    transition: transform 0.4s var(--ease-out), border-color 0.4s var(--ease-out);
}
.why-item::before {
    content: ""; position: absolute; inset: 0;
    border-radius: inherit;
    background: radial-gradient(420px circle at var(--spotlight-x, 50%) var(--spotlight-y, 50%), rgba(110, 241, 255, 0.14), transparent 60%);
    opacity: var(--spotlight-opacity, 0);
    pointer-events: none;
    transition: opacity 0.24s ease;
}
.why-item:hover {
    transform: translateY(-4px);
    border-color: var(--line-strong);
}
.why-item > * { position: relative; z-index: 1; }
.why-index {
    display: inline-block;
    font-family: "Outfit", var(--font-sans);
    font-size: 12.5px; font-weight: 800; letter-spacing: 0.14em;
    color: var(--brand); margin-bottom: 18px; opacity: 0.9;
}
.why-item h3 {
    font-size: 18px; font-weight: 700; letter-spacing: -0.01em;
    margin-bottom: 10px;
}
.why-item p { font-size: 13.5px; line-height: 1.7; color: var(--text-secondary); }

/* ---------- 方案 ---------- */
.solution-panel {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
    gap: clamp(40px, 6vw, 90px);
    align-items: start;
    padding: clamp(44px, 6vw, 76px);
    border-radius: var(--radius-xl);
    background: linear-gradient(180deg, var(--surface-raised), var(--surface));
    border: 1px solid var(--line);
    box-shadow: var(--shadow-card);
    position: relative;
    overflow: hidden;
}
.solution-panel::before {
    content: ""; position: absolute; inset: 0;
    background: radial-gradient(80% 120% at 100% 0%, rgba(125, 133, 255, 0.1), transparent 55%);
}
.solution-copy { position: relative; }
.solution-copy h2 {
    font-size: clamp(36px, 4.8vw, 64px);
    line-height: 1.04; font-weight: 700; letter-spacing: -0.02em;
}
.solution-copy .brand-word {
    background: linear-gradient(100deg, var(--brand), var(--brand-deep));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.solution-specs { position: relative; display: flex; flex-direction: column; }
.spec {
    padding: 22px 0; border-bottom: 1px solid var(--line);
    display: grid; grid-template-columns: 108px 1fr; gap: 24px; align-items: baseline;
}
.spec:first-child { padding-top: 6px; }
.spec:last-child { border-bottom: none; padding-bottom: 0; }
.spec dt {
    font-family: "Outfit", var(--font-sans);
    font-size: 12px; letter-spacing: 0.16em; text-transform: uppercase;
    color: var(--text-muted);
}
.spec dd { font-size: 17px; font-weight: 600; color: var(--text); }

/* ---------- 合作流程 ---------- */
.steps-grid {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 32px;
}
.step-item {
    position: relative;
    padding: 30px 26px;
    border-radius: var(--radius-lg);
    background: var(--surface);
    border: 1px solid var(--line);
    box-shadow: var(--shadow-card);
}
.step-item:not(:last-child)::after {
    content: "";
    position: absolute;
    top: 44px;
    right: -23px;
    width: 14px;
    height: 14px;
    border-top: 1.5px solid var(--line-strong);
    border-right: 1.5px solid var(--line-strong);
    transform: rotate(45deg);
    opacity: 0.7;
}
.step-num {
    display: block;
    font-family: "Outfit", var(--font-sans);
    font-size: 34px;
    font-weight: 800;
    line-height: 1;
    color: var(--brand);
    margin-bottom: 18px;
    letter-spacing: -0.02em;
}
.step-item h3 {
    font-size: 18px;
    font-weight: 700;
    letter-spacing: -0.01em;
    margin-bottom: 10px;
}
.step-item p {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-secondary);
}

/* ---------- 使命 ---------- */
.vision-section {
    text-align: center;
    display: flex; flex-direction: column; align-items: center;
    gap: 48px;
}
.vision-section h2 { font-size: clamp(42px, 7vw, 96px); line-height: 1.04; }
.vision-section h2 .line { display: block; }
.vision-section h2 .line-inner.brand-word {
    color: var(--brand);
}
.vision-section h2 .char-window {
    display: inline-block;
    overflow: hidden;
    vertical-align: top;
    height: 1.04em;
    line-height: 1.04;
}
.vision-section h2 .char-strip {
    display: block;
}
.vision-section h2 .char {
    display: block;
    height: 1.04em;
    line-height: 1.04;
}
.vision-section.is-revealed h2 .char-strip {
    animation: char-shuffle 0.7s var(--ease-out) forwards;
    will-change: transform;
}
@keyframes char-shuffle {
    0% { transform: translateY(0); }
    45% { transform: translateY(-2.08em); }
    100% { transform: translateY(0); }
}

/* ---------- 联系 ---------- */
.contact-inner {
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: clamp(40px, 6vw, 80px);
    align-items: center;
    padding: clamp(40px, 6vw, 64px);
    border-radius: var(--radius-xl);
    background: linear-gradient(180deg, var(--surface-raised), var(--surface));
    border: 1px solid var(--line);
    box-shadow: var(--shadow-card);
}
.contact-copy h2 {
    font-size: clamp(28px, 3.6vw, 46px);
    line-height: 1.12; font-weight: 700; letter-spacing: -0.02em;
    margin-bottom: 18px;
}
.contact-lead { font-size: 16px; color: var(--text-secondary); margin-bottom: 22px; }
.contact-company { font-size: 14px; color: var(--text-muted); margin-bottom: 10px; }
.contact-link {
    display: inline-block;
    font-family: "Outfit", var(--font-sans);
    font-size: 15px; color: var(--brand);
    border-bottom: 1px solid rgba(110, 241, 255, 0.4); padding-bottom: 2px;
}
.contact-link:hover { border-color: var(--brand); }
.contact-qr {
    width: 200px;
    flex-shrink: 0;
    text-align: center;
}
.qr-image {
    width: 200px;
    height: 200px;
    object-fit: contain;
    border-radius: 16px;
    background: #fff;
    padding: 10px;
    border: 1px solid var(--line-strong);
    box-shadow: var(--shadow-card);
}
.qr-hint {
    margin-top: 14px;
    font-size: 13px;
    color: var(--text-muted);
}

/* ---------- Footer ---------- */
.site-footer {
    display: flex; align-items: center; gap: 14px; flex-wrap: wrap;
    padding: 36px clamp(24px, 4vw, 48px) 44px;
    border-top: 1px solid var(--line);
    color: var(--text-muted); font-size: 13px;
    max-width: var(--page-width); margin: 0 auto;
}
.site-footer strong { color: var(--text); font-weight: 700; }
.site-footer .footer-divider { flex: 1; min-width: 20px; }

/* ---------- 回到顶部 ---------- */
.back-to-top {
    position: fixed;
    right: 24px;
    bottom: 24px;
    z-index: 80;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 128px;
    height: 54px;
    border: 1px solid var(--line-strong);
    border-radius: 16px;
    color: var(--text-secondary);
    background: rgba(10, 18, 32, 0.72);
    -webkit-backdrop-filter: blur(22px) saturate(1.2);
    backdrop-filter: blur(22px) saturate(1.2);
    box-shadow: var(--shadow-card);
    font-family: var(--font-sans);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.02em;
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
    transform: translateY(10px);
    transition: opacity 0.25s ease, transform 0.25s var(--ease-out),
        border-color 0.25s var(--ease-out), color 0.25s var(--ease-out);
}
.back-to-top.is-visible {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}
.back-to-top:hover {
    color: var(--text);
    border-color: var(--brand);
    box-shadow: 0 0 30px rgba(110, 241, 255, 0.2);
}

/* ---------- Reveal ---------- */
.reveal {
    opacity: 0; transform: translateY(28px);
    transition: opacity 0.8s var(--ease-out), transform 0.8s var(--ease-out);
    transition-delay: var(--reveal-delay, 0s);
}
.reveal.is-visible { opacity: 1; transform: translateY(0); }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
    .cap-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .why-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .steps-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .step-item:nth-child(2)::after { display: none; }
    .solution-panel { grid-template-columns: 1fr; }
    .contact-inner { grid-template-columns: 1fr; }
}
@media (max-width: 600px) {
    .site-header,
    .site-header.is-scrolled {
        top: 12px;
        width: calc(100% - 24px);
        min-height: 54px;
        padding: 6px 8px 6px 14px;
        border-radius: 14px;
    }
    .cap-grid { grid-template-columns: 1fr; }
    .why-grid { grid-template-columns: 1fr; }
    .pain-list { grid-template-columns: 1fr; }
    .pain-section h2 { white-space: normal; }
    .steps-grid { grid-template-columns: 1fr; }
    .step-item:not(:last-child)::after { display: none; }
    .site-nav a:not(.nav-cta) { display: none; }
    .spec { grid-template-columns: 1fr; gap: 6px; }
}

@media (prefers-reduced-motion: reduce) {
    * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}