/* ==========================================================
   北部湾物流系统 · 门户站统一样式
   设计语言：深海军蓝 × 港口科技感 × 大气留白
   ========================================================== */

:root {
    --navy-900: #071a30;
    --navy-800: #0a2540;
    --navy-700: #0f3460;
    --navy-600: #14467e;
    --blue-500: #2f7fd1;
    --cyan-400: #38bdf8;
    --cyan-300: #7dd3fc;
    --gold-400: #e2b45a;
    --ink-900: #16283c;
    --ink-600: #4a5c70;
    --ink-400: #7c8ba0;
    --line: #e3eaf2;
    --bg-soft: #f4f7fb;
    --bg-white: #ffffff;
    --shadow-lg: 0 24px 60px -18px rgba(10, 37, 64, 0.25);
    --shadow-md: 0 12px 32px -12px rgba(10, 37, 64, 0.18);
    --shadow-sm: 0 4px 14px -4px rgba(10, 37, 64, 0.12);
    --radius: 14px;
    --grad-hero: linear-gradient(160deg, rgba(7, 26, 48, 0.88) 0%, rgba(15, 52, 96, 0.72) 45%, rgba(7, 26, 48, 0.9) 100%);
    --grad-accent: linear-gradient(120deg, #38bdf8 0%, #2f7fd1 60%, #5ea0e8 100%);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Microsoft Yahei", "PingFang SC", system-ui, sans-serif;
    background: var(--bg-soft);
    color: var(--ink-900);
    line-height: 1.75;
    -webkit-font-smoothing: antialiased;
}

a {
    text-decoration: none;
    color: inherit;
}

img {
    max-width: 100%;
    display: block;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ----------------------------------------------------------
   顶部导航
---------------------------------------------------------- */
header {
    position: sticky;
    top: 0;
    z-index: 999;
    background: rgba(7, 26, 48, 0.82);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.nav-wrap {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 72px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-wrap {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-mark {
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: var(--grad-accent);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: 0 6px 18px -6px rgba(56, 189, 248, 0.6);
}

.logo-mark svg {
    width: 22px;
    height: 22px;
}

.logo-text {
    color: #fff;
    font-size: 19px;
    font-weight: 700;
    letter-spacing: 1px;
    line-height: 1.3;
}

.logo-text small {
    display: block;
    font-size: 11px;
    font-weight: 400;
    letter-spacing: 2.5px;
    color: rgba(255, 255, 255, 0.55);
    text-transform: uppercase;
}

nav {
    display: flex;
    align-items: center;
    gap: 8px;
}

nav a {
    position: relative;
    color: rgba(255, 255, 255, 0.78);
    font-size: 15px;
    padding: 8px 16px;
    border-radius: 8px;
    transition: color .25s, background .25s;
}

nav a:hover {
    color: #fff;
    background: rgba(255, 255, 255, 0.08);
}

nav a.active {
    color: var(--cyan-300);
    font-weight: 600;
}

nav a.active::after {
    content: "";
    position: absolute;
    left: 16px;
    right: 16px;
    bottom: 2px;
    height: 2px;
    border-radius: 2px;
    background: var(--grad-accent);
}

/* ----------------------------------------------------------
   首页 Hero
---------------------------------------------------------- */
.hero {
    position: relative;
    min-height: calc(100vh - 72px);
    display: flex;
    align-items: center;
    overflow: hidden;
    background: var(--navy-900);
}

.hero-bg {
    position: absolute;
    inset: 0;
    background-size: cover;
    background-position: center;
    animation: heroZoom 24s ease-in-out infinite alternate;
}

@keyframes heroZoom {
    from { transform: scale(1); }
    to   { transform: scale(1.12); }
}

.hero-mask {
    position: absolute;
    inset: 0;
    background: var(--grad-hero);
}

.hero-inner {
    position: relative;
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 110px 24px 140px;
    color: #fff;
}

.hero-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
    letter-spacing: 4px;
    color: var(--cyan-300);
    border: 1px solid rgba(125, 211, 252, 0.35);
    padding: 8px 18px;
    border-radius: 999px;
    background: rgba(56, 189, 248, 0.08);
    margin-bottom: 28px;
}

.hero-eyebrow::before {
    content: "";
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--cyan-400);
    box-shadow: 0 0 12px var(--cyan-400);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: .35; }
}

.hero h1 {
    font-size: clamp(38px, 5.4vw, 66px);
    font-weight: 800;
    letter-spacing: 2px;
    line-height: 1.22;
    margin-bottom: 22px;
    text-shadow: 0 6px 30px rgba(0, 0, 0, 0.45);
}

.hero h1 em {
    font-style: normal;
    background: linear-gradient(120deg, #7dd3fc, #38bdf8 45%, #e2b45a);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.hero-sub {
    font-size: clamp(16px, 2vw, 20px);
    color: rgba(255, 255, 255, 0.82);
    max-width: 640px;
    margin-bottom: 44px;
    letter-spacing: 1px;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 18px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 15px 36px;
    border-radius: 999px;
    font-size: 16px;
    font-weight: 600;
    letter-spacing: 1px;
    transition: transform .25s, box-shadow .25s, background .25s;
}

.btn-primary {
    background: var(--grad-accent);
    color: #fff;
    box-shadow: 0 14px 34px -10px rgba(56, 189, 248, 0.65);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 20px 44px -10px rgba(56, 189, 248, 0.75);
}

.btn-ghost {
    color: #fff;
    border: 1px solid rgba(255, 255, 255, 0.45);
    background: rgba(255, 255, 255, 0.06);
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.14);
    transform: translateY(-3px);
}

.hero-scroll {
    position: absolute;
    left: 50%;
    bottom: 34px;
    transform: translateX(-50%);
    color: rgba(255, 255, 255, 0.6);
    font-size: 12px;
    letter-spacing: 3px;
    text-align: center;
}

.hero-scroll span {
    display: block;
    width: 1px;
    height: 42px;
    margin: 10px auto 0;
    background: linear-gradient(to bottom, rgba(255,255,255,.7), transparent);
    animation: scrollHint 2s infinite;
}

@keyframes scrollHint {
    0% { transform: scaleY(0); transform-origin: top; }
    55% { transform: scaleY(1); transform-origin: top; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* 首页轮播背景（相对本 CSS 文件定位） */
.bg1 { background-image: url('/static/portal/images/bg1.jpg'); }
.bg2 { background-image: url('/static/portal/images/bg2.jpg'); }
.bg3 { background-image: url('/static/portal/images/bg3.jpg'); }
.bg4 { background-image: url('/static/portal/images/bg4.jpg'); }

/* 轮播（首页 hero 背景切换） */
.hero-bg-slide {
    position: absolute;
    inset: 0;
    opacity: 0;
    background-size: cover;
    background-position: center;
    transition: opacity 1.6s ease;
}

.hero-bg-slide.show {
    opacity: 1;
    animation: heroZoom 22s ease-in-out infinite alternate;
}

/* ----------------------------------------------------------
   数据条
---------------------------------------------------------- */
.stats-strip {
    position: relative;
    z-index: 2;
    margin-top: -70px;
}

.stats-card {
    background: var(--bg-white);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    overflow: hidden;
}

.stat {
    padding: 40px 20px;
    text-align: center;
    position: relative;
}

.stat + .stat::before {
    content: "";
    position: absolute;
    left: 0;
    top: 26%;
    bottom: 26%;
    width: 1px;
    background: var(--line);
}

.stat .num {
    font-size: 40px;
    font-weight: 800;
    background: var(--grad-accent);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    line-height: 1.2;
}

.stat .num sup {
    font-size: 20px;
}

.stat .label {
    margin-top: 6px;
    color: var(--ink-600);
    font-size: 15px;
    letter-spacing: 1px;
}

/* ----------------------------------------------------------
   通用板块
---------------------------------------------------------- */
.section {
    padding: 96px 0;
}

.section.alt {
    background: var(--bg-white);
}

.section-head {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 64px;
}

.section-head .eyebrow {
    display: inline-block;
    font-size: 13px;
    letter-spacing: 5px;
    color: var(--blue-500);
    text-transform: uppercase;
    margin-bottom: 14px;
    font-weight: 600;
}

.section-head h2 {
    font-size: clamp(28px, 3.6vw, 40px);
    color: var(--navy-800);
    font-weight: 800;
    letter-spacing: 2px;
    margin-bottom: 14px;
}

.section-head p {
    color: var(--ink-600);
    font-size: 16px;
}

.section-head .bar {
    width: 64px;
    height: 4px;
    border-radius: 4px;
    background: var(--grad-accent);
    margin: 18px auto 0;
}

/* ----------------------------------------------------------
   产品卡片
---------------------------------------------------------- */
.grid-4 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(255px, 1fr));
    gap: 26px;
}

.p-card {
    background: var(--bg-white);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 40px 30px;
    position: relative;
    overflow: hidden;
    transition: transform .35s ease, box-shadow .35s ease, border-color .35s;
}

.p-card::before {
    content: "";
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    height: 4px;
    background: var(--grad-accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform .4s ease;
}

.p-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-md);
    border-color: transparent;
}

.p-card:hover::before {
    transform: scaleX(1);
}

.p-icon {
    width: 62px;
    height: 62px;
    border-radius: 16px;
    background: linear-gradient(150deg, rgba(56, 189, 248, 0.14), rgba(47, 127, 209, 0.12));
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
}

.p-icon svg {
    width: 30px;
    height: 30px;
    stroke: var(--blue-500);
}

.p-card h4 {
    font-size: 20px;
    color: var(--navy-800);
    margin-bottom: 12px;
    letter-spacing: 1px;
}

.p-card p {
    color: var(--ink-600);
    font-size: 15px;
}

.p-card .tag {
    position: absolute;
    right: 22px;
    top: 22px;
    font-size: 12px;
    letter-spacing: 2px;
    color: rgba(47, 127, 209, 0.35);
    font-weight: 700;
}

/* ----------------------------------------------------------
   解决方案
---------------------------------------------------------- */
.sol-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 26px;
}

.sol-item {
    display: flex;
    gap: 20px;
    background: var(--bg-white);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 32px 28px;
    transition: transform .3s, box-shadow .3s;
}

.sol-item:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}

.sol-num {
    flex-shrink: 0;
    width: 52px;
    height: 52px;
    border-radius: 50%;
    background: var(--grad-accent);
    color: #fff;
    font-size: 20px;
    font-weight: 800;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 20px -8px rgba(47, 127, 209, 0.7);
}

.sol-item h4 {
    font-size: 18px;
    color: var(--navy-800);
    margin-bottom: 8px;
}

.sol-item p {
    font-size: 15px;
    color: var(--ink-600);
}

/* 声明条 */
.declare-band {
    margin-top: 56px;
    border-radius: var(--radius);
    background: linear-gradient(120deg, #0a2540, #14467e);
    color: rgba(255, 255, 255, 0.9);
    padding: 30px 36px;
    display: flex;
    gap: 18px;
    align-items: flex-start;
    font-size: 15px;
    line-height: 1.8;
}

.declare-band .d-icon {
    flex-shrink: 0;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    border: 1px solid rgba(255, 255, 255, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.declare-band strong {
    color: var(--cyan-300);
}

/* ----------------------------------------------------------
   关于（图文分栏）
---------------------------------------------------------- */
.about-split {
    display: grid;
    grid-template-columns: 1.05fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-visual {
    position: relative;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    aspect-ratio: 16 / 11;
    background-size: cover;
    background-position: center;
}

.about-visual::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to top, rgba(7, 26, 48, 0.55), transparent 55%);
}

.about-badge {
    position: absolute;
    z-index: 2;
    left: 26px;
    bottom: 24px;
    color: #fff;
}

.about-badge .b1 {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 1px;
}

.about-badge .b2 {
    font-size: 13px;
    color: rgba(255, 255, 255, 0.75);
    letter-spacing: 2px;
}

.about-copy h3 {
    font-size: clamp(24px, 3vw, 32px);
    color: var(--navy-800);
    letter-spacing: 1px;
    margin-bottom: 20px;
}

.about-copy p {
    color: var(--ink-600);
    margin-bottom: 16px;
    font-size: 15.5px;
}

.about-points {
    margin: 26px 0 34px;
    display: grid;
    gap: 12px;
}

.about-points li {
    list-style: none;
    display: flex;
    gap: 12px;
    align-items: flex-start;
    color: var(--ink-900);
    font-size: 15px;
}

.about-points .dot {
    flex-shrink: 0;
    width: 22px;
    height: 22px;
    margin-top: 3px;
    border-radius: 50%;
    background: rgba(47, 127, 209, 0.12);
    color: var(--blue-500);
    font-size: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
}

/* ----------------------------------------------------------
   联系 CTA
---------------------------------------------------------- */
.cta-band {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius);
    background: linear-gradient(130deg, #0a2540 0%, #0f3460 55%, #14467e 100%);
    color: #fff;
    padding: 70px 60px;
    box-shadow: var(--shadow-lg);
}

.cta-band::before {
    content: "";
    position: absolute;
    right: -80px;
    top: -80px;
    width: 320px;
    height: 320px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(56, 189, 248, 0.28), transparent 65%);
}

.cta-band::after {
    content: "";
    position: absolute;
    right: 120px;
    bottom: -120px;
    width: 260px;
    height: 260px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(226, 180, 90, 0.18), transparent 65%);
}

.cta-band h3 {
    position: relative;
    font-size: clamp(24px, 3vw, 34px);
    letter-spacing: 2px;
    margin-bottom: 14px;
}

.cta-band p {
    position: relative;
    color: rgba(255, 255, 255, 0.78);
    margin-bottom: 34px;
    max-width: 560px;
}

.cta-band .btn {
    position: relative;
}

/* ----------------------------------------------------------
   联系信息卡
---------------------------------------------------------- */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 26px;
}

.c-card {
    background: var(--bg-white);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 36px 30px;
    text-align: center;
    transition: transform .3s, box-shadow .3s;
}

.c-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-md);
}

.c-card .p-icon {
    margin: 0 auto 18px;
}

.c-card h4 {
    font-size: 16px;
    color: var(--ink-400);
    font-weight: 500;
    letter-spacing: 2px;
    margin-bottom: 8px;
}

.c-card .val {
    font-size: 17px;
    color: var(--navy-800);
    font-weight: 600;
    word-break: break-all;
}

/* ----------------------------------------------------------
   内页 Banner
---------------------------------------------------------- */
.page-banner {
    position: relative;
    padding: 110px 0 90px;
    background-size: cover;
    background-position: center;
    color: #fff;
    overflow: hidden;
}

.page-banner::before {
    content: "";
    position: absolute;
    inset: 0;
    background: var(--grad-hero);
}

.page-banner .inner {
    position: relative;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.page-banner .crumb {
    font-size: 13px;
    letter-spacing: 3px;
    color: var(--cyan-300);
    text-transform: uppercase;
    margin-bottom: 14px;
    font-weight: 600;
}

.page-banner h1 {
    font-size: clamp(32px, 4.4vw, 50px);
    font-weight: 800;
    letter-spacing: 3px;
    margin-bottom: 12px;
}

.page-banner p {
    color: rgba(255, 255, 255, 0.8);
    font-size: 16px;
    max-width: 620px;
}

/* ----------------------------------------------------------
   详情列表卡（产品/方案内页）
---------------------------------------------------------- */
.d-card {
    display: grid;
    grid-template-columns: 96px 1fr;
    gap: 30px;
    background: var(--bg-white);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 44px 42px;
    margin-bottom: 26px;
    transition: box-shadow .3s, transform .3s;
}

.d-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.d-card .p-icon {
    width: 78px;
    height: 78px;
    margin: 0;
}

.d-card .p-icon svg {
    width: 38px;
    height: 38px;
}

.d-card h4 {
    font-size: 21px;
    color: var(--navy-800);
    letter-spacing: 1px;
    margin-bottom: 10px;
}

.d-card p {
    color: var(--ink-600);
    font-size: 15.5px;
}

.d-card .features {
    margin-top: 14px;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
}

.d-card .features span {
    font-size: 13px;
    color: var(--blue-500);
    background: rgba(47, 127, 209, 0.08);
    border: 1px solid rgba(47, 127, 209, 0.18);
    padding: 4px 14px;
    border-radius: 999px;
}

/* 关于页信息表 */
.info-list {
    display: grid;
    gap: 0;
    margin-top: 26px;
    border-top: 1px solid var(--line);
}

.info-list .row {
    display: grid;
    grid-template-columns: 140px 1fr;
    gap: 20px;
    padding: 16px 4px;
    border-bottom: 1px solid var(--line);
    font-size: 15px;
}

.info-list .row .k {
    color: var(--ink-400);
    letter-spacing: 2px;
}

.info-list .row .v {
    color: var(--ink-900);
    font-weight: 500;
}

/* ----------------------------------------------------------
   页脚
---------------------------------------------------------- */
footer {
    background: var(--navy-900);
    color: rgba(255, 255, 255, 0.62);
    margin-top: 96px;
}

.footer-top {
    max-width: 1200px;
    margin: 0 auto;
    padding: 64px 24px 40px;
    display: grid;
    grid-template-columns: 1.4fr 1fr 1fr;
    gap: 48px;
}

.footer-brand .logo-text {
    font-size: 18px;
    margin-bottom: 14px;
    display: block;
}

.footer-brand p {
    font-size: 14px;
    line-height: 1.9;
    max-width: 360px;
}

.footer-col h5 {
    color: #fff;
    font-size: 15px;
    letter-spacing: 2px;
    margin-bottom: 18px;
    font-weight: 600;
}

.footer-col a,
.footer-col p {
    display: block;
    color: rgba(255, 255, 255, 0.6);
    font-size: 14px;
    padding: 5px 0;
    transition: color .25s;
}

.footer-col a:hover {
    color: var(--cyan-300);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.08);
    text-align: center;
    padding: 22px 20px 26px;
    font-size: 13px;
    line-height: 2;
}

.footer-bottom p {
    margin: 0;
}

/* 备案号区域：工信部 ICP + 公安网安 */
.beian {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 0 18px;
    margin-top: 4px;
}

.beian p {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    margin: 0;
    line-height: 1.6;
}

.beian-icon {
    width: 14px;
    height: 14px;
    flex-shrink: 0;
    display: inline-block;
    vertical-align: middle;
}

@media (max-width: 480px) {
    .beian {
        gap: 2px 12px;
    }
    .beian p {
        font-size: 12px;
    }
}

.footer-bottom a {
    color: var(--cyan-300);
}

.footer-bottom a:hover {
    text-decoration: underline;
}

/* ----------------------------------------------------------
   滚动进场动画
---------------------------------------------------------- */
.reveal {
    opacity: 0;
    transform: translateY(34px);
    transition: opacity .8s ease, transform .8s ease;
}

.reveal.visible {
    opacity: 1;
    transform: none;
}

.reveal.d1 { transition-delay: .08s; }
.reveal.d2 { transition-delay: .16s; }
.reveal.d3 { transition-delay: .24s; }
.reveal.d4 { transition-delay: .32s; }

/* ----------------------------------------------------------
   响应式
---------------------------------------------------------- */
/* 触屏设备：移除悬浮依赖的微动效（性能 + 防误触） */
@media (hover: none) {
    .p-card:hover,
    .sol-item:hover,
    .c-card:hover,
    .d-card:hover,
    .btn-primary:hover,
    .btn-ghost:hover {
        transform: none;
    }
}

@media (max-width: 1100px) {
    .container { padding: 0 20px; }
    .footer-top { padding: 56px 20px 32px; gap: 40px; }
}

@media (max-width: 960px) {
    .hero-inner { padding: 90px 20px 130px; }
    .about-split {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .footer-top {
        grid-template-columns: 1fr 1fr;
    }
    .stats-card {
        grid-template-columns: repeat(2, 1fr);
    }
    .stat:nth-child(3)::before {
        display: none;
    }
    .page-banner { padding: 90px 0 70px; }
}

/* 平板及以下：启用汉堡菜单 */
@media (max-width: 820px) {
    /* 导航折叠为汉堡菜单 */
    .nav-toggle {
        display: flex;
    }
    header.nav-open .nav-wrap nav {
        display: flex;
        animation: navSlide .3s ease;
    }
    .nav-wrap {
        height: 64px;
        padding: 0 20px;
        position: relative;
    }
    nav {
        display: none;
        position: absolute;
        left: 0;
        right: 0;
        top: 64px;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        background: rgba(7, 26, 48, 0.96);
        backdrop-filter: blur(16px);
        -webkit-backdrop-filter: blur(16px);
        border-bottom: 1px solid rgba(255, 255, 255, 0.08);
        padding: 8px 16px 16px;
        box-shadow: 0 18px 30px -12px rgba(0, 0, 0, 0.4);
        max-height: calc(100vh - 64px);
        overflow-y: auto;
    }
    nav a {
        padding: 14px 12px;
        font-size: 15px;
        border-radius: 8px;
        text-align: left;
        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }
    nav a:last-child { border-bottom: none; }
    nav a.active::after { display: none; }
    nav a.active {
        background: rgba(56, 189, 248, 0.12);
    }
    /* 汉堡菜单按钮 */
    .nav-toggle {
        display: flex;
        width: 44px;
        height: 44px;
        align-items: center;
        justify-content: center;
        background: transparent;
        border: none;
        border-radius: 10px;
        cursor: pointer;
        margin-left: auto;
        color: #fff;
        transition: background .2s;
    }
    .nav-toggle:hover { background: rgba(255, 255, 255, 0.08); }
    .nav-toggle:active { background: rgba(255, 255, 255, 0.15); }
    .nav-toggle span {
        display: block;
        width: 22px;
        height: 2px;
        background: #fff;
        position: relative;
        transition: transform .25s, opacity .2s;
        border-radius: 2px;
    }
    .nav-toggle span::before,
    .nav-toggle span::after {
        content: "";
        position: absolute;
        left: 0;
        width: 22px;
        height: 2px;
        background: #fff;
        border-radius: 2px;
        transition: transform .25s;
    }
    .nav-toggle span::before { top: -7px; }
    .nav-toggle span::after  { top: 7px; }
    /* 展开状态：X 形 */
    header.nav-open .nav-toggle span { background: transparent; }
    header.nav-open .nav-toggle span::before { transform: translateY(7px) rotate(45deg); }
    header.nav-open .nav-toggle span::after  { transform: translateY(-7px) rotate(-45deg); }

    /* logo 在中等屏缩小一些 */
    .logo-text { font-size: 17px; }
    .logo-text small { font-size: 10px; letter-spacing: 2px; }
    .logo-mark { width: 36px; height: 36px; border-radius: 9px; }
    .logo-mark svg { width: 20px; height: 20px; }

    .section { padding: 76px 0; }
    .section-head { margin-bottom: 48px; }
}

@keyframes navSlide {
    from { opacity: 0; transform: translateY(-8px); }
    to   { opacity: 1; transform: none; }
}

@media (max-width: 640px) {
    body { line-height: 1.7; }
    .container { padding: 0 16px; }
    .hero-inner {
        padding: 60px 18px 110px;
    }
    .hero h1 { letter-spacing: 1px; }
    .hero-sub { margin-bottom: 32px; }
    .hero-eyebrow { font-size: 12px; letter-spacing: 3px; padding: 6px 14px; margin-bottom: 22px; }
    .hero-actions { gap: 12px; }
    .btn { padding: 14px 28px; font-size: 15px; }
    .hero-scroll { font-size: 11px; bottom: 22px; }
    .hero-scroll span { height: 32px; }

    .stats-card { border-radius: 12px; }
    .stat { padding: 28px 14px; }
    .stat .num { font-size: 30px; }
    .stat .num sup { font-size: 16px; }
    .stat .label { font-size: 13px; }

    .section { padding: 56px 0; }
    .section-head { margin-bottom: 36px; }
    .section-head p { font-size: 14px; }

    .grid-4 { gap: 16px; }
    .p-card { padding: 28px 22px; }
    .p-card .tag { right: 16px; top: 16px; font-size: 11px; }
    .p-card h4 { font-size: 17px; }
    .p-card p { font-size: 14px; }

    .sol-grid { gap: 16px; }
    .sol-item { padding: 24px 20px; gap: 16px; }
    .sol-num { width: 44px; height: 44px; font-size: 17px; }
    .sol-item h4 { font-size: 16px; }
    .sol-item p { font-size: 14px; }

    .declare-band { padding: 22px 22px; gap: 12px; font-size: 13.5px; line-height: 1.75; }
    .declare-band .d-icon { width: 36px; height: 36px; font-size: 16px; }

    .about-copy h3 { font-size: 22px; }
    .about-copy p { font-size: 14.5px; }
    .about-points { margin: 20px 0 26px; }
    .about-points li { font-size: 14px; gap: 10px; }
    .about-points .dot { width: 20px; height: 20px; font-size: 11px; }

    .cta-band { padding: 40px 24px; }
    .cta-band h3 { font-size: 22px; letter-spacing: 1px; }
    .cta-band p { font-size: 14.5px; margin-bottom: 26px; }

    .contact-grid { gap: 16px; }
    .c-card { padding: 26px 20px; }
    .c-card .val { font-size: 15px; }

    .page-banner { padding: 70px 0 50px; }
    .page-banner .inner { padding: 0 18px; }
    .page-banner h1 { letter-spacing: 2px; }
    .page-banner p { font-size: 14.5px; }
    .page-banner .crumb { letter-spacing: 2.5px; font-size: 12px; }

    .d-card { padding: 26px 22px; margin-bottom: 18px; }
    .d-card .p-icon { width: 56px; height: 56px; margin: 0; }
    .d-card .p-icon svg { width: 28px; height: 28px; }
    .d-card h4 { font-size: 18px; }
    .d-card p { font-size: 14px; }
    .d-card .features { gap: 8px; }
    .d-card .features span { font-size: 12px; padding: 3px 11px; }

    .info-list { margin-top: 18px; }
    .info-list .row { padding: 13px 0; gap: 14px; font-size: 14px; }
    .info-list .row .k { letter-spacing: 1px; }

    .footer-top { grid-template-columns: 1fr; gap: 28px; padding: 44px 20px 28px; }
    .footer-brand .logo-text { font-size: 16px; }
    .footer-brand p { font-size: 13.5px; }
    .footer-col h5 { font-size: 14px; margin-bottom: 12px; }
    .footer-col a, .footer-col p { font-size: 13.5px; padding: 4px 0; }
    .footer-bottom { padding: 18px 16px 22px; font-size: 12px; line-height: 1.9; }
}

/* 小屏手机（≤380px，iPhone SE 等） */
@media (max-width: 380px) {
    .container { padding: 0 14px; }
    .nav-wrap { padding: 0 14px; }
    .hero-inner { padding: 50px 14px 100px; }
    .hero-actions .btn { width: 100%; justify-content: center; padding: 13px 22px; }
    .stats-card { grid-template-columns: 1fr; }
    .stat + .stat::before { display: none; }
    .stat { padding: 22px 12px; border-top: 1px solid var(--line); }
    .stats-strip { margin-top: -40px; }
    .p-card { padding: 24px 18px; }
    .sol-item { padding: 22px 18px; }
    .d-card { padding: 22px 18px; }
    .cta-band { padding: 34px 20px; }
    .footer-top { padding: 40px 18px 24px; }
}

/* 平板/手机横屏 */
@media (max-height: 500px) and (orientation: landscape) {
    .hero { min-height: 480px; }
    .hero-inner { padding: 60px 24px 80px; }
    .hero-scroll { display: none; }
    .stats-strip { margin-top: -50px; }
}

/* 折叠屏展开（仅宽度变大） */
@media (min-width: 821px) {
    .nav-toggle { display: none; }
}

/* 减少动效（系统偏好） */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: .001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: .001ms !important;
    }
    html { scroll-behavior: auto; }
    .hero-bg-slide.show { animation: none; }
}