/* =========================================================================
 * StarSail 首页（Home / Landing Page）
 * 方案 A · 航海旅程叙事
 * 主题：深海蓝 + 黄金锚 + 星沙米
 * ========================================================================= */

:root {
    /* 品牌色 */
    --deep-sea: #0B1D3A;
    --deep-sea-2: #0F2547;
    --deep-sea-3: #152C5C;
    --star-sand: #E8DCC8;
    --star-sand-2: #F2E9D8;
    --gold-anchor: #E8A93A;
    --gold-anchor-2: #F4B848;
    --gold-soft: rgba(232, 169, 58, 0.12);
    --star-blue: #5B9BD5;
    --ink-100: #FFFFFF;
    --ink-200: #E8DCC8;
    --ink-300: #8A93B8;
    --ink-400: #5A628A;
    --ink-dark: #1A1A1A;
    --ink-mid: #4A4A4A;
    --ink-light: #8A8A8A;
    --line-soft: rgba(255, 255, 255, 0.08);
    --line-mid: rgba(255, 255, 255, 0.14);
    --line-light: #E5E5E5;

    /* 尺寸 */
    --container: 1200px;
    --container-narrow: 880px;
    --radius-lg: 24px;
    --radius-md: 16px;
    --radius-sm: 12px;
    --radius-pill: 999px;

    /* 阴影 */
    --shadow-soft: 0 8px 32px rgba(11, 29, 58, 0.08);
    --shadow-mid: 0 16px 48px rgba(11, 29, 58, 0.12);
    --shadow-gold: 0 12px 36px rgba(232, 169, 58, 0.25);
}

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

[hidden] {
    display: none !important;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Outfit', 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--deep-sea);
    color: var(--ink-100);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

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

a {
    color: var(--gold-anchor);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: var(--gold-anchor-2);
}

.serif {
    font-family: 'Cormorant Garamond', 'Noto Serif SC', 'Source Han Serif SC', 'Songti SC', serif;
    font-weight: 500;
    letter-spacing: 0.01em;
}

.container {
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 24px;
}

.container-narrow {
    max-width: var(--container-narrow);
    margin: 0 auto;
    padding: 0 24px;
}

/* =========================================================================
 * 顶部导航
 * ========================================================================= */

.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    padding: 16px 0;
    background: transparent;
    transition: background 0.3s, backdrop-filter 0.3s, padding 0.3s;
}

.nav.scrolled {
    background: rgba(11, 29, 58, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    padding: 12px 0;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.15);
}

.nav-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 24px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-family: 'Cormorant Garamond', serif;
    font-size: 22px;
    font-weight: 600;
    color: var(--ink-100);
    letter-spacing: 0.02em;
}

.nav-logo-icon {
    color: var(--gold-anchor);
    font-size: 24px;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
}

.nav-menu a {
    color: var(--ink-200);
    font-size: 15px;
    font-weight: 400;
    position: relative;
    transition: color 0.2s;
}

.nav-menu a::after {
    content: '';
    position: absolute;
    left: 50%;
    bottom: -6px;
    width: 0;
    height: 2px;
    background: var(--gold-anchor);
    transition: all 0.25s ease;
    transform: translateX(-50%);
}

.nav-menu a:hover {
    color: var(--gold-anchor);
}

.nav-menu a:hover::after {
    width: 100%;
}

.nav-cta {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 10px 22px;
    background: var(--gold-anchor);
    color: var(--deep-sea);
    font-weight: 600;
    font-size: 14px;
    border-radius: var(--radius-pill);
    transition: all 0.25s;
}

.nav-cta:hover {
    background: var(--gold-anchor-2);
    color: var(--deep-sea);
    transform: translateY(-1px);
    box-shadow: var(--shadow-gold);
}

.nav-toggle {
    display: none;
    background: transparent;
    border: 0;
    color: var(--ink-100);
    font-size: 24px;
    cursor: pointer;
    padding: 4px 8px;
}

/* =========================================================================
 * 章节通用
 * ========================================================================= */

.section {
    padding: 120px 0;
    position: relative;
    overflow: hidden;
}

.section--light {
    background: var(--star-sand);
    color: var(--ink-dark);
}

.section--sand {
    background: var(--star-sand-2);
    color: var(--ink-dark);
}

.section--white {
    background: #FFFFFF;
    color: var(--ink-dark);
}

.section--deep {
    background: var(--deep-sea);
    color: var(--ink-100);
}

.section-eyebrow {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--gold-anchor);
    margin-bottom: 16px;
    padding: 6px 14px;
    background: var(--gold-soft);
    border-radius: var(--radius-pill);
}

.section-eyebrow--dark {
    color: var(--deep-sea);
    background: rgba(11, 29, 58, 0.08);
}

.section-title {
    font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
    font-size: clamp(32px, 4.5vw, 48px);
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 20px;
    letter-spacing: 0.01em;
}

.section-subtitle {
    font-size: 18px;
    color: var(--ink-light);
    max-width: 720px;
    margin: 0 auto 60px;
    line-height: 1.7;
}

.section--light .section-subtitle,
.section--sand .section-subtitle,
.section--white .section-subtitle {
    color: var(--ink-mid);
}

.section-header {
    text-align: center;
    margin-bottom: 80px;
}

/* 元素进入动画 */
.fade-in {
    opacity: 0;
    transform: translateY(28px);
    transition: opacity 0.7s ease-out, transform 0.7s ease-out;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* =========================================================================
 * 章节 ① Hero
 * ========================================================================= */

.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background:
        radial-gradient(ellipse at 30% 30%, rgba(91, 155, 213, 0.18) 0%, transparent 50%),
        radial-gradient(ellipse at 70% 70%, rgba(232, 169, 58, 0.12) 0%, transparent 45%),
        linear-gradient(180deg, #0B1D3A 0%, #0F2547 100%);
    position: relative;
    padding: 120px 24px 80px;
    overflow: hidden;
}

/* 星辰粒子 */
.starfield {
    position: absolute;
    inset: 0;
    pointer-events: none;
}

.star {
    position: absolute;
    background: #FFFFFF;
    border-radius: 50%;
    animation: twinkle 4s infinite ease-in-out;
}

@keyframes twinkle {

    0%,
    100% {
        opacity: 0.3;
        transform: scale(1);
    }

    50% {
        opacity: 0.9;
        transform: scale(1.4);
    }
}

.hero-anchor {
    position: absolute;
    right: 5%;
    bottom: 10%;
    width: 200px;
    height: 200px;
    opacity: 0.15;
    pointer-events: none;
}

@media (max-width: 768px) {
    .hero-anchor {
        width: 120px;
        height: 120px;
        right: -20px;
        bottom: 5%;
    }
}

.hero-content {
    max-width: 880px;
    position: relative;
    z-index: 1;
}

.hero-mark {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: rgba(232, 169, 58, 0.12);
    border: 1px solid rgba(232, 169, 58, 0.3);
    color: var(--gold-anchor);
    font-size: 32px;
    margin-bottom: 32px;
    animation: float 6s infinite ease-in-out;
}

@keyframes float {

    0%,
    100% {
        transform: translateY(0);
    }

    50% {
        transform: translateY(-8px);
    }
}

.hero-brand {
    font-family: 'Cormorant Garamond', serif;
    font-size: clamp(36px, 5vw, 56px);
    font-weight: 500;
    color: var(--ink-100);
    margin-bottom: 8px;
    letter-spacing: 0.02em;
}

.hero-brand-zh {
    font-family: 'Noto Serif SC', 'Songti SC', serif;
    font-size: 18px;
    color: var(--ink-200);
    letter-spacing: 0.4em;
    margin-bottom: 32px;
}

.hero-title {
    font-family: 'Cormorant Garamond', 'Noto Serif SC', serif;
    font-size: clamp(40px, 6vw, 72px);
    font-weight: 600;
    line-height: 1.15;
    color: var(--ink-100);
    margin-bottom: 12px;
    letter-spacing: 0.01em;
}

.hero-slogan {
    font-family: 'Cormorant Garamond', serif;
    font-style: italic;
    font-size: clamp(20px, 2.5vw, 28px);
    color: var(--gold-anchor);
    margin-bottom: 40px;
    letter-spacing: 0.15em;
}

.hero-quote {
    max-width: 600px;
    margin: 0 auto 48px;
    padding: 24px 32px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--line-soft);
    border-radius: var(--radius-md);
    backdrop-filter: blur(20px);
}

.hero-quote p {
    font-family: 'Noto Serif SC', serif;
    font-size: 17px;
    line-height: 1.8;
    color: var(--ink-200);
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 16px 32px;
    border-radius: var(--radius-pill);
    font-size: 16px;
    font-weight: 600;
    transition: all 0.25s;
    cursor: pointer;
    border: 0;
    text-decoration: none;
    font-family: inherit;
}

.btn--primary {
    background: var(--gold-anchor);
    color: var(--deep-sea);
    box-shadow: var(--shadow-gold);
}

.btn--primary:hover {
    background: var(--gold-anchor-2);
    color: var(--deep-sea);
    transform: translateY(-2px);
    box-shadow: 0 16px 40px rgba(232, 169, 58, 0.35);
}

.btn--ghost {
    background: transparent;
    color: var(--ink-100);
    border: 1.5px solid rgba(255, 255, 255, 0.3);
}

.btn--ghost:hover {
    background: rgba(255, 255, 255, 0.08);
    border-color: var(--ink-100);
    color: var(--ink-100);
    transform: translateY(-2px);
}

.btn--dark {
    background: var(--deep-sea);
    color: var(--ink-100);
}

.btn--dark:hover {
    background: var(--deep-sea-2);
    color: var(--ink-100);
    transform: translateY(-2px);
}

.scroll-hint {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--ink-300);
    font-size: 13px;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    animation: float 3s infinite ease-in-out;
}

.scroll-arrow {
    width: 1px;
    height: 32px;
    background: linear-gradient(180deg, var(--gold-anchor), transparent);
    position: relative;
}

.scroll-arrow::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 6px;
    height: 6px;
    border-right: 1px solid var(--gold-anchor);
    border-bottom: 1px solid var(--gold-anchor);
    transform: translateX(-50%) rotate(45deg);
}

/* =========================================================================
 * 章节 ② 四大核心能力
 * ========================================================================= */

.features {
    display: flex;
    flex-direction: column;
    gap: 96px;
}

.feature {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 64px;
    align-items: center;
}

.feature:nth-child(even) {
    direction: rtl;
}

.feature:nth-child(even) > * {
    direction: ltr;
}

.feature-mock {
    aspect-ratio: 4 / 3;
    background: linear-gradient(135deg, #F8F1E0 0%, var(--star-sand) 100%);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-mid);
    position: relative;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
}

.feature-mock-inner {
    width: 80%;
    height: 80%;
    background: rgba(255, 255, 255, 0.7);
    border-radius: 16px;
    box-shadow: 0 8px 24px rgba(11, 29, 58, 0.08);
    display: flex;
    flex-direction: column;
    padding: 16px;
    gap: 8px;
}

.mock-line {
    height: 8px;
    background: rgba(11, 29, 58, 0.08);
    border-radius: 4px;
}

.mock-line--short {
    width: 50%;
}

.mock-line--gold {
    background: var(--gold-anchor);
    width: 30%;
    height: 12px;
}

.mock-card {
    flex: 1;
    background: rgba(91, 155, 213, 0.1);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--star-blue);
    font-size: 32px;
}

.feature-content {
    padding: 0 16px;
}

.feature-number {
    display: inline-block;
    font-family: 'Cormorant Garamond', serif;
    font-size: 56px;
    font-weight: 500;
    color: var(--gold-anchor);
    line-height: 1;
    margin-bottom: 16px;
}

.feature-title {
    font-family: 'Noto Serif SC', 'Cormorant Garamond', serif;
    font-size: 32px;
    font-weight: 600;
    color: var(--ink-dark);
    margin-bottom: 16px;
    line-height: 1.3;
}

.feature-desc {
    font-size: 17px;
    color: var(--ink-mid);
    line-height: 1.8;
    margin-bottom: 24px;
}

.feature-story {
    padding: 16px 20px;
    background: rgba(232, 169, 58, 0.08);
    border-left: 3px solid var(--gold-anchor);
    border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
    font-size: 14px;
    color: var(--ink-mid);
    line-height: 1.7;
    font-style: italic;
}

.section--white .feature-mock {
    background: linear-gradient(135deg, #F5F0E5 0%, var(--star-sand-2) 100%);
}

/* =========================================================================
 * 章节 ③ 核心特色
 * ========================================================================= */

.highlights {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.highlight {
    padding: 32px 20px;
    background: var(--star-sand);
    border-radius: var(--radius-md);
    text-align: center;
    transition: all 0.3s;
    position: relative;
    overflow: hidden;
}

.highlight::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, var(--gold-anchor) 0%, var(--gold-anchor-2) 100%);
    opacity: 0;
    transition: opacity 0.3s;
    z-index: 0;
}

.highlight:hover {
    transform: translateY(-6px);
}

.highlight:hover::before {
    opacity: 1;
}

.highlight:hover .highlight-title,
.highlight:hover .highlight-desc {
    color: var(--deep-sea);
}

.highlight-icon {
    font-size: 40px;
    margin-bottom: 12px;
    display: block;
    position: relative;
    z-index: 1;
    transition: transform 0.3s;
}

.highlight:hover .highlight-icon {
    transform: scale(1.15) rotate(-6deg);
}

.highlight-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 18px;
    font-weight: 600;
    color: var(--deep-sea);
    margin-bottom: 8px;
    position: relative;
    z-index: 1;
    transition: color 0.3s;
}

.highlight-desc {
    font-size: 13px;
    color: var(--ink-mid);
    line-height: 1.6;
    position: relative;
    z-index: 1;
    transition: color 0.3s;
}

/* =========================================================================
 * 章节 ④ 3 步上手
 * ========================================================================= */

.steps {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    position: relative;
    max-width: 1000px;
    margin: 0 auto 60px;
}

.steps::before {
    content: '';
    position: absolute;
    top: 36px;
    left: 16.6%;
    right: 16.6%;
    height: 2px;
    background: linear-gradient(90deg,
            var(--gold-anchor) 0%,
            var(--gold-anchor) 100%);
    opacity: 0.3;
    z-index: 0;
}

.step {
    text-align: center;
    position: relative;
    z-index: 1;
}

.step-num {
    width: 72px;
    height: 72px;
    margin: 0 auto 20px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--gold-anchor) 0%, var(--gold-anchor-2) 100%);
    color: var(--ink-100);
    font-family: 'Cormorant Garamond', serif;
    font-size: 32px;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-gold);
    border: 4px solid #FFFFFF;
}

.step-icon {
    font-size: 40px;
    margin-bottom: 12px;
    display: block;
}

.step-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 22px;
    font-weight: 600;
    color: var(--ink-dark);
    margin-bottom: 8px;
}

.step-desc {
    font-size: 14px;
    color: var(--ink-mid);
    line-height: 1.7;
    margin-bottom: 8px;
}

.step-sub {
    font-size: 12px;
    color: var(--ink-light);
    font-style: italic;
}

.steps-summary {
    text-align: center;
    font-family: 'Noto Serif SC', serif;
    font-size: 18px;
    color: var(--ink-mid);
    padding: 24px 32px;
    background: rgba(232, 169, 58, 0.08);
    border-radius: var(--radius-md);
    max-width: 720px;
    margin: 0 auto;
}

.steps-summary .gold {
    color: var(--gold-anchor);
    font-weight: 600;
}

/* =========================================================================
 * 章节 ⑤ 目标设备支持
 * ========================================================================= */

.devices {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 40px;
}

.device {
    padding: 32px 24px;
    background: #FFFFFF;
    border-radius: var(--radius-md);
    text-align: center;
    box-shadow: var(--shadow-soft);
    transition: all 0.3s;
    border: 1px solid var(--line-light);
}

.device:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-mid);
    border-color: var(--gold-anchor);
}

.device-icon {
    width: 72px;
    height: 72px;
    margin: 0 auto 20px;
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gold-anchor);
    position: relative;
    background: linear-gradient(135deg, #1A1A1A 0%, #0B1D3A 100%);
    border: 1px solid rgba(232, 169, 58, 0.15);
    transition: all 0.3s;
}

.device-icon svg {
    width: 60%;
    height: 60%;
    max-width: 56px;
    max-height: 56px;
}

.device:hover .device-icon {
    border-color: var(--gold-anchor);
    transform: translateY(-2px);
}

.device-icon--track {
    background: linear-gradient(135deg, #0F2547 0%, #152C5C 100%);
}

.device-icon--rect {
    background: linear-gradient(135deg, #1A1A1A 0%, #0B1D3A 100%);
}

.device-icon--circle {
    background: linear-gradient(135deg, #152C5C 0%, #0F2547 100%);
}

.device-icon--watch {
    background: linear-gradient(135deg, #0B1D3A 0%, #1A1A1A 100%);
}

.device-category {
    font-family: 'Outfit', sans-serif;
    font-size: 11px;
    font-weight: 600;
    color: var(--gold-anchor);
    letter-spacing: 0.18em;
    text-transform: uppercase;
    margin-bottom: 6px;
}

.device-list {
    font-size: 12px;
    color: var(--ink-light);
    margin-bottom: 12px;
    line-height: 1.5;
}

.device-name {
    font-family: 'Noto Serif SC', serif;
    font-size: 17px;
    font-weight: 600;
    color: var(--ink-dark);
    margin-bottom: 6px;
}

.device-badge {
    display: inline-block;
    padding: 4px 10px;
    background: rgba(110, 231, 183, 0.15);
    color: #0D7A50;
    font-size: 12px;
    font-weight: 600;
    border-radius: var(--radius-pill);
}

.devices-more {
    text-align: center;
    font-size: 14px;
    color: var(--ink-mid);
    font-style: italic;
}

/* =========================================================================
 * 章节 ⑥ 团队 & 联系方式
 * ========================================================================= */

.about-team {
    max-width: 720px;
    margin: 0 auto 48px;
    padding: 40px 48px;
    background: #FFFFFF;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-soft);
    text-align: center;
}

.about-team p {
    font-family: 'Noto Serif SC', serif;
    font-size: 17px;
    line-height: 1.9;
    color: var(--ink-mid);
}

.about-team .accent {
    color: var(--gold-anchor);
    font-weight: 600;
}

.about-team .lead {
    font-size: 19px;
    color: var(--ink-dark);
    margin-bottom: 16px;
}

.about-contact {
    max-width: 720px;
    margin: 0 auto 64px;
}

.about-contact-title {
    font-family: 'Noto Serif SC', serif;
    font-size: 22px;
    font-weight: 600;
    color: var(--ink-dark);
    text-align: center;
    margin-bottom: 24px;
}

.about-contact-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.about-contact-item {
    display: flex;
    align-items: center;
    gap: 14px;
    padding: 18px 22px;
    background: #FFFFFF;
    border: 1px solid var(--line-light);
    border-radius: var(--radius-md);
    text-decoration: none;
    color: var(--ink-dark);
    transition: all 0.25s;
    box-shadow: var(--shadow-soft);
}

a.about-contact-item:hover {
    border-color: var(--gold-anchor);
    transform: translateY(-2px);
    box-shadow: var(--shadow-mid);
    color: var(--ink-dark);
}

.about-contact-item--static {
    cursor: default;
}

.about-contact-icon {
    font-size: 24px;
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gold-soft);
    border-radius: 50%;
}

.about-contact-label {
    display: block;
    font-size: 12px;
    color: var(--ink-light);
    margin-bottom: 2px;
    letter-spacing: 0.05em;
}

.about-contact-value {
    display: block;
    font-family: 'Outfit', monospace;
    font-size: 15px;
    font-weight: 600;
    color: var(--deep-sea);
    letter-spacing: 0.02em;
}

.about-footer {
    text-align: center;
    border-top: 1px solid var(--line-light);
    padding-top: 32px;
    max-width: 720px;
    margin: 0 auto;
}

.about-footer-copy {
    font-size: 14px;
    color: var(--ink-light);
    margin-bottom: 12px;
}

.about-footer-links {
    display: flex;
    gap: 24px;
    justify-content: center;
    font-size: 13px;
}

.about-footer-links a {
    color: var(--ink-mid);
}

.about-footer-links a:hover {
    color: var(--gold-anchor);
}

.about-footer-icp {
    text-align: center;
    margin-top: 16px;
    font-size: 13px;
    color: var(--ink-light);
}

.about-footer-icp a {
    color: var(--ink-light);
}

.about-footer-icp a:hover {
    color: var(--gold-anchor);
}

/* =========================================================================
 * 浮动 CTA
 * ========================================================================= */

.float-cta {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(120%);
    z-index: 90;
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px 24px;
    background: var(--gold-anchor);
    color: var(--deep-sea);
    border-radius: var(--radius-pill);
    box-shadow: var(--shadow-gold);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    max-width: calc(100% - 32px);
}

.float-cta.show {
    transform: translateX(-50%) translateY(0);
}

.float-cta-text {
    font-weight: 600;
    font-size: 14px;
}

.float-cta-actions {
    display: flex;
    gap: 8px;
}

.float-cta-btn {
    padding: 6px 14px;
    background: var(--deep-sea);
    color: var(--ink-100);
    font-size: 13px;
    font-weight: 500;
    border-radius: var(--radius-pill);
    transition: background 0.2s;
}

.float-cta-btn--ghost {
    background: transparent;
    color: var(--deep-sea);
    border: 1px solid var(--deep-sea);
}

.float-cta-btn:hover {
    background: var(--deep-sea-2);
}

.float-cta-btn--ghost:hover {
    background: var(--deep-sea);
    color: var(--ink-100);
}

/* =========================================================================
 * 响应式 - 平板
 * ========================================================================= */

@media (max-width: 1023px) {

    .section {
        padding: 80px 0;
    }

    .section-header {
        margin-bottom: 56px;
    }

    .feature {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .feature:nth-child(even) {
        direction: ltr;
    }

    .feature-mock {
        max-width: 480px;
        margin: 0 auto;
    }

    .highlights {
        grid-template-columns: repeat(3, 1fr);
    }

    .steps {
        gap: 24px;
    }

    .devices {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* =========================================================================
 * 响应式 - 手机
 * ========================================================================= */

@media (max-width: 767px) {
    :root {
        --container: 100%;
    }

    body {
        font-size: 15px;
    }

    .section {
        padding: 64px 0;
    }

    .container,
    .container-narrow,
    .nav-inner {
        padding: 0 20px;
    }

    /* 导航：折叠为汉堡 */
    .nav-menu {
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        width: 80%;
        max-width: 320px;
        background: var(--deep-sea-2);
        flex-direction: column;
        align-items: flex-start;
        padding: 80px 32px 32px;
        gap: 24px;
        transform: translateX(100%);
        transition: transform 0.3s;
        box-shadow: -8px 0 32px rgba(0, 0, 0, 0.3);
    }

    .nav-menu.open {
        transform: translateX(0);
    }

    .nav-menu a {
        font-size: 17px;
    }

    .nav-toggle {
        display: block;
        z-index: 110;
    }

    .nav-cta-desktop {
        display: none;
    }

    /* Hero */
    .hero {
        min-height: 92vh;
        padding: 100px 20px 60px;
    }

    .hero-mark {
        width: 60px;
        height: 60px;
        font-size: 28px;
    }

    .hero-quote {
        padding: 20px 24px;
    }

    .hero-quote p {
        font-size: 15px;
    }

    .hero-cta {
        flex-direction: column;
        width: 100%;
        max-width: 320px;
        margin: 0 auto;
    }

    .btn {
        width: 100%;
        padding: 14px 24px;
    }

    .scroll-hint {
        display: none;
    }

    /* 通用 */
    .section-eyebrow {
        font-size: 12px;
        padding: 5px 12px;
    }

    .section-title {
        font-size: 28px;
    }

    .section-subtitle {
        font-size: 15px;
        margin-bottom: 40px;
    }

    .section-header {
        margin-bottom: 40px;
    }

    /* 章节 ② */
    .features {
        gap: 64px;
    }

    .feature {
        gap: 24px;
    }

    .feature-number {
        font-size: 40px;
        margin-bottom: 8px;
    }

    .feature-title {
        font-size: 22px;
    }

    .feature-desc {
        font-size: 15px;
    }

    .feature-content {
        padding: 0;
    }

    /* 章节 ③ */
    .highlights {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }

    .highlight {
        padding: 24px 12px;
    }

    .highlight-icon {
        font-size: 32px;
    }

    .highlight-title {
        font-size: 15px;
    }

    .highlight-desc {
        font-size: 12px;
    }

    /* 章节 ⑥ */
    .steps {
        grid-template-columns: 1fr;
        gap: 32px;
        max-width: 360px;
    }

    .steps::before {
        display: none;
    }

    .step-num {
        width: 60px;
        height: 60px;
        font-size: 26px;
    }

    .step-title {
        font-size: 19px;
    }

    .steps-summary {
        font-size: 15px;
        padding: 20px 24px;
    }

    /* 章节 ⑦ */
    .devices {
        grid-template-columns: 1fr 1fr;
        gap: 12px;
    }

    .device {
        padding: 24px 16px;
    }

    .device-icon {
        width: 56px;
        height: 56px;
        border-radius: 14px;
    }

    .device-name {
        font-size: 15px;
    }

    .device-list {
        font-size: 11px;
    }

    /* 章节 ⑥ */
    .about-team {
        padding: 28px 20px;
    }

    .about-team p {
        font-size: 15px;
    }

    .about-team .lead {
        font-size: 16px;
    }

    .about-contact-list {
        grid-template-columns: 1fr;
    }

    .about-contact-item {
        padding: 14px 18px;
    }

    .about-contact-value {
        font-size: 14px;
    }

    /* 浮动 CTA */
    .float-cta {
        flex-direction: column;
        gap: 8px;
        padding: 12px 16px;
        border-radius: var(--radius-md);
        max-width: calc(100% - 24px);
    }

    .float-cta-text {
        font-size: 13px;
    }

    .float-cta-actions {
        width: 100%;
    }

    .float-cta-btn {
        flex: 1;
        text-align: center;
    }
}

@media (max-width: 380px) {
    .highlights {
        grid-template-columns: 1fr;
    }

    .devices {
        grid-template-columns: 1fr;
    }
}

/* =========================================================================
 * 减少动效（无障碍）
 * ========================================================================= */

@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        transition-duration: 0.01ms !important;
    }

    html {
        scroll-behavior: auto;
    }
}