/* ============================================================
   冰球突破 · 极光冰晶设计系统
   域名：bingqiutupo77.cn
   风格：冰晶玻璃态 + 极光几何切割
   特色：冰蓝白底 × 极光紫点缀 × 冰晶质感
   ============================================================ */

/* ----- 基础重置 & 变量 ----- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 冰晶色板 — 完全无黑色/深色背景 */
    --ice-white:       #F4F9FF;
    --ice-bg:          #EDF4FA;
    --ice-mist:        #E1EDF7;
    --ice-light:       #D1E3F2;
    --ice-blue:        #8AB8D9;
    --ice-crystal:     #4A8BC2;
    --ice-deep:        #2A6A9E;
    --aurora-light:    #C4B5E8;
    --aurora:          #8B6CCE;
    --aurora-deep:     #6C4FA8;
    --mint-frost:      #5ECCC8;
    --text-dark:       #1A2D44;
    --text-mid:        #4A6E8A;
    --text-light:      #7A9AB5;
    --glass-bg:        rgba(255, 255, 255, 0.58);
    --glass-border:    rgba(255, 255, 255, 0.82);
    --glass-shadow:    0 12px 36px rgba(74, 139, 194, 0.10);
    --grad-aurora:     linear-gradient(135deg, #4A8BC2 0%, #8B6CCE 70%, #5ECCC8 100%);
    --grad-ice:        linear-gradient(145deg, #F4F9FF 0%, #E1EDF7 100%);
    --grad-card:       linear-gradient(165deg, rgba(255,255,255,0.9) 0%, rgba(232,241,250,0.5) 100%);
    --aurora-glow:     0 0 40px rgba(139, 108, 206, 0.25);
    --ice-glow:        0 0 30px rgba(74, 139, 194, 0.15);
}

body {
    font-family: system-ui, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    overflow-x: hidden;
    background: var(--ice-white);
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
}

/* ----- 核心布局 ----- */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 88px 0;
    position: relative;
    background: var(--ice-white);
}

.section:nth-child(even) {
    background: var(--ice-bg);
}

/* 冰晶装饰光晕 */
.section::before {
    content: '';
    position: absolute;
    top: -20%;
    left: -10%;
    width: 50%;
    height: 80%;
    background: radial-gradient(ellipse at 30% 50%, rgba(139, 108, 206, 0.06) 0%, transparent 70%);
    pointer-events: none;
    z-index: 0;
}

.section:nth-child(even)::before {
    left: auto;
    right: -10%;
    background: radial-gradient(ellipse at 70% 50%, rgba(74, 139, 194, 0.06) 0%, transparent 70%);
}

.section > .container {
    position: relative;
    z-index: 1;
}

/* ----- 导航 — 冰晶玻璃态 ----- */
.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: var(--glass-bg);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    border-bottom: 1px solid var(--glass-border);
    box-shadow: 0 4px 30px rgba(74, 139, 194, 0.06);
}

.site-header::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--grad-aurora);
    opacity: 0.4;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 68px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 1.25rem;
    text-decoration: none;
    color: var(--text-dark);
    letter-spacing: 1px;
    position: relative;
}

.logo-icon {
    width: 38px;
    height: 38px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.1rem;
    background: var(--grad-aurora);
    color: #fff;
    box-shadow: 0 4px 16px rgba(139, 108, 206, 0.3);
    position: relative;
    overflow: hidden;
}

.logo-icon::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.4) 0%, transparent 50%);
    border-radius: inherit;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 28px;
    list-style: none;
}

.main-nav a {
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--text-mid);
    transition: all 0.3s ease;
    position: relative;
    padding: 4px 0;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--grad-aurora);
    border-radius: 2px;
    transition: width 0.35s ease;
}

.main-nav a:hover {
    color: var(--ice-deep);
}

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

.nav-cta {
    padding: 9px 24px !important;
    border-radius: 40px !important;
    color: #fff !important;
    font-weight: 600 !important;
    background: var(--grad-aurora) !important;
    box-shadow: 0 4px 18px rgba(139, 108, 206, 0.30) !important;
    transition: all 0.3s ease !important;
    position: relative;
    overflow: hidden;
}

.nav-cta::after {
    display: none !important;
}

.nav-cta::before {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.25) 0%, transparent 60%);
    border-radius: inherit;
}

.nav-cta:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 8px 30px rgba(139, 108, 206, 0.40) !important;
    color: #fff !important;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    border-radius: 8px;
    background: var(--ice-mist);
}

.menu-toggle span {
    width: 22px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 4px;
    transition: 0.3s;
}

/* ----- Hero — 冰晶突破 · 极光竞速 ----- */
.hero {
    min-height: 80vh;
    display: flex;
    align-items: center;
    padding-top: 68px;
    background: var(--grad-ice);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background:
        radial-gradient(ellipse at 20% 80%, rgba(74, 139, 194, 0.10) 0%, transparent 60%),
        radial-gradient(ellipse at 80% 20%, rgba(139, 108, 206, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 50%, rgba(94, 204, 200, 0.04) 0%, transparent 40%);
    pointer-events: none;
}

/* 冰晶六边形装饰 */
.hero::after {
    content: '';
    position: absolute;
    top: -10%;
    right: -5%;
    width: 600px;
    height: 600px;
    background:
        repeating-linear-gradient(60deg, transparent, transparent 30px, rgba(138, 184, 217, 0.06) 30px, rgba(138, 184, 217, 0.06) 31px),
        repeating-linear-gradient(-60deg, transparent, transparent 30px, rgba(138, 184, 217, 0.06) 30px, rgba(138, 184, 217, 0.06) 31px);
    clip-path: polygon(50% 0%, 100% 25%, 100% 75%, 50% 100%, 0% 75%, 0% 25%);
    opacity: 0.5;
    pointer-events: none;
    animation: floatHex 20s ease-in-out infinite;
}

@keyframes floatHex {
    0%, 100% { transform: translate(0, 0) rotate(0deg) scale(1); }
    33% { transform: translate(20px, -20px) rotate(5deg) scale(1.02); }
    66% { transform: translate(-10px, 10px) rotate(-3deg) scale(0.98); }
}

.hero-content {
    max-width: 720px;
    position: relative;
    z-index: 1;
}

.hero-eyebrow {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 3px;
    padding: 6px 18px;
    border-radius: 40px;
    margin-bottom: 20px;
    background: linear-gradient(135deg, rgba(74, 139, 194, 0.12), rgba(139, 108, 206, 0.12));
    color: var(--ice-deep);
    border: 1px solid rgba(74, 139, 194, 0.15);
    text-transform: uppercase;
}

.hero h1 {
    font-size: 3.4rem;
    line-height: 1.15;
    margin-bottom: 18px;
    font-weight: 800;
    letter-spacing: -0.5px;
    background: var(--grad-aurora);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-shadow: none;
    position: relative;
}

.hero h1::after {
    content: '⚡';
    position: absolute;
    right: -60px;
    top: -10px;
    font-size: 2rem;
    -webkit-text-fill-color: initial;
    color: var(--mint-frost);
    animation: pulseGlow 2s ease-in-out infinite;
}

@keyframes pulseGlow {
    0%, 100% { opacity: 0.6; transform: scale(1) rotate(0deg); }
    50% { opacity: 1; transform: scale(1.2) rotate(10deg); }
}

.hero p {
    font-size: 1.15rem;
    color: var(--text-mid);
    max-width: 540px;
    margin-bottom: 36px;
    line-height: 1.7;
    font-weight: 400;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
}

.hero-image {
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--glass-shadow), var(--ice-glow);
    background: var(--grad-card);
    border: 1px solid var(--glass-border);
    position: relative;
}

.hero-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* ----- 按钮 — 冰晶光泽 + 极光渐变 ----- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 13px 32px;
    border-radius: 40px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    text-decoration: none;
    transition: all 0.35s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    font-size: 0.95rem;
    position: relative;
    overflow: hidden;
}

.btn::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.20) 0%, transparent 50%);
    border-radius: inherit;
    pointer-events: none;
}

.btn-primary {
    color: #fff;
    background: var(--grad-aurora);
    box-shadow: 0 6px 24px rgba(139, 108, 206, 0.30);
}

.btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 12px 40px rgba(139, 108, 206, 0.40);
}

.btn-outline {
    background: transparent;
    border: 1.5px solid rgba(74, 139, 194, 0.30);
    color: var(--ice-deep);
    backdrop-filter: blur(4px);
}

.btn-outline:hover {
    border-color: var(--aurora);
    background: rgba(139, 108, 206, 0.06);
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(139, 108, 206, 0.10);
}

/* ----- 标签 / 标题 — 冰晶排版 ----- */
.section-label {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 3px;
    text-transform: uppercase;
    margin-bottom: 14px;
    color: var(--ice-crystal);
    padding: 4px 16px;
    border-radius: 30px;
    background: rgba(74, 139, 194, 0.08);
    border: 1px solid rgba(74, 139, 194, 0.12);
}

.section-title {
    font-size: 2.3rem;
    font-weight: 800;
    margin-bottom: 16px;
    line-height: 1.2;
    letter-spacing: -0.3px;
    color: var(--text-dark);
}

.section-title .highlight {
    background: var(--grad-aurora);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.section-desc {
    max-width: 600px;
    color: var(--text-mid);
    font-size: 1.05rem;
    margin-bottom: 44px;
    line-height: 1.7;
}

/* ----- 卡片网格 — 冰晶玻璃态卡片 ----- */
.cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 28px;
}

.category-card {
    border-radius: 16px;
    padding: 32px 28px;
    background: var(--grad-card);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    backdrop-filter: blur(8px);
    transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--grad-aurora);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.category-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 50px rgba(74, 139, 194, 0.15), var(--aurora-glow);
    border-color: rgba(139, 108, 206, 0.15);
}

.category-card:hover::before {
    opacity: 1;
}

.card-icon {
    width: 52px;
    height: 52px;
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 1.4rem;
    background: var(--grad-aurora);
    color: #fff;
    box-shadow: 0 6px 20px rgba(139, 108, 206, 0.25);
    position: relative;
}

.card-icon::after {
    content: '';
    position: absolute;
    inset: 0;
    border-radius: inherit;
    background: linear-gradient(135deg, rgba(255,255,255,0.30) 0%, transparent 50%);
}

.category-card h3 {
    font-size: 1.15rem;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-dark);
}

.category-card p {
    color: var(--text-mid);
    font-size: 0.9rem;
    line-height: 1.6;
    margin-bottom: 16px;
}

.card-link {
    font-weight: 600;
    font-size: 0.85rem;
    text-decoration: none;
    color: var(--aurora);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: gap 0.3s ease;
}

.card-link:hover {
    gap: 12px;
    color: var(--aurora-deep);
}

/* ----- 特性块 — 冰晶左右布局 ----- */
.feature-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.feature-image {
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--glass-shadow), var(--ice-glow);
    border: 1px solid var(--glass-border);
    background: var(--grad-card);
}

.feature-image img {
    width: 100%;
    height: auto;
    display: block;
}

.feature-text h3 {
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: 14px;
    color: var(--text-dark);
}

.feature-text p {
    color: var(--text-mid);
    line-height: 1.7;
    margin-bottom: 20px;
}

.feature-list {
    list-style: none;
}

.feature-list li {
    padding: 8px 0;
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--text-dark);
    font-weight: 500;
}

.feature-list li::before {
    content: '✦';
    font-weight: 700;
    color: var(--aurora);
    font-size: 0.9rem;
}

/* ----- 数据条 — 冰晶数字 ----- */
.stats-bar {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    text-align: center;
}

.stat-item {
    padding: 32px 20px;
    border-radius: 16px;
    background: var(--grad-card);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    backdrop-filter: blur(6px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.stat-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 16px 40px rgba(74, 139, 194, 0.12);
}

.stat-number {
    font-size: 2.6rem;
    font-weight: 800;
    background: var(--grad-aurora);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    line-height: 1.1;
    letter-spacing: -1px;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-mid);
    margin-top: 8px;
    font-weight: 500;
}

/* ----- 内容墙 — 冰晶资讯卡片 ----- */
.content-wall {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 28px;
}

.content-wall-item {
    border-radius: 16px;
    overflow: hidden;
    background: var(--grad-card);
    border: 1px solid var(--glass-border);
    box-shadow: var(--glass-shadow);
    transition: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.content-wall-item:hover {
    transform: translateY(-6px);
    box-shadow: 0 20px 50px rgba(74, 139, 194, 0.15), var(--aurora-glow);
    border-color: rgba(139, 108, 206, 0.15);
}

.content-wall-item img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    display: block;
    transition: transform 0.5s ease;
}

.content-wall-item:hover img {
    transform: scale(1.04);
}

.content-wall-body {
    padding: 22px 24px 26px;
}

.content-wall-body .tag {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    color: var(--ice-crystal);
    background: rgba(74, 139, 194, 0.08);
    padding: 3px 12px;
    border-radius: 30px;
    margin-bottom: 10px;
}

.content-wall-body h3 {
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 8px;
    color: var(--text-dark);
    line-height: 1.4;
}

.content-wall-body p {
    color: var(--text-mid);
    font-size: 0.88rem;
    line-height: 1.6;
}

/* ----- FAQ — 冰晶折叠 ----- */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border: 1px solid rgba(74, 139, 194, 0.12);
    border-radius: 14px;
    margin-bottom: 10px;
    overflow: hidden;
    cursor: pointer;
    background: var(--grad-card);
    backdrop-filter: blur(6px);
    transition: box-shadow 0.3s ease;
}

.faq-item:hover {
    box-shadow: 0 4px 20px rgba(74, 139, 194, 0.06);
}

.faq-item .faq-question {
    padding: 18px 24px;
    font-weight: 600;
    font-size: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--text-dark);
    transition: color 0.3s ease;
}

.faq-item .faq-question::after {
    content: '❄';
    font-size: 0.8rem;
    transition: transform 0.4s ease, color 0.3s ease;
    color: var(--ice-blue);
}

.faq-item.open .faq-question::after {
    transform: rotate(180deg);
    color: var(--aurora);
}

.faq-item .faq-answer {
    padding: 0 24px 20px;
    display: none;
    color: var(--text-mid);
    line-height: 1.7;
    font-size: 0.93rem;
}

.faq-item.open .faq-answer {
    display: block;
}

.faq-item.open {
    border-color: rgba(139, 108, 206, 0.20);
    box-shadow: 0 4px 24px rgba(139, 108, 206, 0.06);
}

/* ----- CTA横幅 — 极光冰晶 ----- */
.cta-banner {
    padding: 64px 40px;
    text-align: center;
    border-radius: 20px;
    color: #fff;
    background: var(--grad-aurora);
    box-shadow: 0 20px 60px rgba(139, 108, 206, 0.30);
    position: relative;
    overflow: hidden;
}

.cta-banner::before {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 30% 20%, rgba(255,255,255,0.20) 0%, transparent 50%),
        radial-gradient(ellipse at 70% 80%, rgba(94, 204, 200, 0.15) 0%, transparent 50%);
    pointer-events: none;
}

.cta-banner h2 {
    font-size: 2rem;
    font-weight: 800;
    color: #fff;
    margin-bottom: 14px;
    position: relative;
    z-index: 1;
}

.cta-banner p {
    color: rgba(255, 255, 255, 0.85);
    max-width: 500px;
    margin: 0 auto 28px;
    font-size: 1.05rem;
    position: relative;
    z-index: 1;
}

.cta-banner .btn-primary {
    background: #fff;
    color: var(--aurora-deep);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.12);
    position: relative;
    z-index: 1;
}

.cta-banner .btn-primary:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: 0 14px 40px rgba(0, 0, 0, 0.18);
}

.cta-banner .btn-primary::after {
    background: linear-gradient(135deg, rgba(139, 108, 206, 0.06) 0%, transparent 50%);
}

/* ----- 页脚 — 冰蓝极光 ----- */
.site-footer {
    padding: 64px 0 32px;
    background: linear-gradient(145deg, #E8F1FA 0%, #DCE8F2 100%);
    border-top: 1px solid rgba(74, 139, 194, 0.08);
    position: relative;
}

.site-footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: var(--grad-aurora);
    opacity: 0.3;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 48px;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.footer-brand .logo {
    font-size: 1.1rem;
}

.footer-brand p {
    color: var(--text-mid);
    font-size: 0.88rem;
    line-height: 1.7;
    max-width: 280px;
}

.footer-col h4 {
    font-size: 0.9rem;
    font-weight: 700;
    margin-bottom: 16px;
    color: var(--text-dark);
    letter-spacing: 1px;
    text-transform: uppercase;
}

.footer-col ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.footer-col ul a {
    text-decoration: none;
    color: var(--text-mid);
    font-size: 0.88rem;
    transition: color 0.3s ease, padding-left 0.3s ease;
}

.footer-col ul a:hover {
    color: var(--aurora);
    padding-left: 4px;
}

.footer-bottom {
    border-top: 1px solid rgba(74, 139, 194, 0.10);
    margin-top: 40px;
    padding-top: 20px;
    text-align: center;
    font-size: 0.82rem;
    color: var(--text-light);
    letter-spacing: 0.5px;
}

/* ----- 工具类 ----- */
.text-accent {
    color: var(--aurora);
}

.text-center {
    text-align: center;
}

.seo-description {
    max-width: 620px;
    margin: 0 auto 48px;
    color: var(--text-mid);
    font-size: 1rem;
    line-height: 1.7;
}

.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

/* ----- 额外冰晶装饰元素 ----- */
.ice-divider {
    width: 60px;
    height: 3px;
    background: var(--grad-aurora);
    border-radius: 4px;
    margin: 0 auto 20px;
}

.ice-texture-bg {
    background-image:
        radial-gradient(circle at 30% 40%, rgba(74, 139, 194, 0.03) 0%, transparent 40%),
        radial-gradient(circle at 70% 60%, rgba(139, 108, 206, 0.03) 0%, transparent 40%);
}

/* ----- 响应式 — 冰晶适配 ----- */
@media (max-width: 1024px) {
    .hero h1 {
        font-size: 2.6rem;
    }
    .hero h1::after {
        right: -30px;
        font-size: 1.4rem;
    }
    .stats-bar {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 32px;
    }
}

@media (max-width: 768px) {
    .hero {
        min-height: 60vh;
        padding: 100px 0 60px;
    }
    .hero h1 {
        font-size: 2rem;
    }
    .hero h1::after {
        display: none;
    }
    .hero p {
        font-size: 1rem;
    }
    .feature-block {
        grid-template-columns: 1fr;
        gap: 36px;
    }
    .section-title {
        font-size: 1.7rem;
    }
    .main-nav {
        display: none;
    }
    .menu-toggle {
        display: flex;
    }
    .main-nav.open {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 68px;
        left: 0;
        width: 100%;
        background: var(--glass-bg);
        backdrop-filter: blur(20px);
        padding: 24px 28px;
        gap: 16px;
        border-bottom: 1px solid var(--glass-border);
        box-shadow: 0 12px 40px rgba(0,0,0,0.06);
    }
    .main-nav.open a {
        font-size: 1rem;
        padding: 8px 0;
    }
    .main-nav.open .nav-cta {
        text-align: center;
        margin-top: 8px;
    }
    .stats-bar {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
    .stat-number {
        font-size: 2rem;
    }
    .footer-grid {
        grid-template-columns: 1fr 1fr;
        gap: 28px;
    }
    .cta-banner {
        padding: 44px 24px;
    }
    .cta-banner h2 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .cards-grid,
    .content-wall,
    .stats-bar {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .footer-brand p {
        max-width: 100%;
    }
    .hero-buttons {
        flex-direction: column;
        align-items: stretch;
    }
    .hero-buttons .btn {
        justify-content: center;
    }
    .hero h1 {
        font-size: 1.7rem;
    }
    .section {
        padding: 56px 0;
    }
    .section-title {
        font-size: 1.4rem;
    }
    .stat-number {
        font-size: 1.8rem;
    }
}

/* ----- 动画关键帧 ----- */
@keyframes shimmer {
    0% { background-position: -200% center; }
    100% { background-position: 200% center; }
}

.shimmer-text {
    background: linear-gradient(90deg, var(--ice-crystal) 0%, var(--aurora) 50%, var(--mint-frost) 100%);
    background-size: 200% auto;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: shimmer 4s linear infinite;
}

/* 冰晶光晕脉冲 */
@keyframes auroraPulse {
    0%, 100% { opacity: 0.4; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.02); }
}

.aurora-glow {
    animation: auroraPulse 4s ease-in-out infinite;
}

/* 滚动条 — 冰晶风格 */
::-webkit-scrollbar {
    width: 6px;
}

::-webkit-scrollbar-track {
    background: var(--ice-bg);
}

::-webkit-scrollbar-thumb {
    background: var(--ice-blue);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--ice-crystal);
}