/* ============================================
   ExMail 企业邮箱 - 主样式表
   ============================================ */

/* CSS 变量 */
:root {
    --color-primary: #1677FF;
    --color-primary-dark: #0958D9;
    --color-primary-light: #4096FF;
    --color-primary-bg: #E6F4FF;
    --color-accent: #FF6A00;
    --color-accent-dark: #D4380D;
    --color-success: #00B4A6;
    --color-danger: #FF4D4F;
    --color-purple: #7B61FF;

    --color-text: #1D2129;
    --color-text-secondary: #4E5969;
    --color-text-tertiary: #86909C;
    --color-text-light: #C9CDD4;

    --color-bg: #FFFFFF;
    --color-bg-gray: #F7F8FA;
    --color-bg-dark: #1D2129;
    --color-border: #E5E6EB;
    --color-border-light: #F2F3F5;

    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, sans-serif;
    --font-size-xs: 12px;
    --font-size-sm: 14px;
    --font-size-base: 16px;
    --font-size-lg: 18px;
    --font-size-xl: 20px;
    --font-size-2xl: 24px;
    --font-size-3xl: 30px;
    --font-size-4xl: 36px;
    --font-size-5xl: 48px;
    --font-size-6xl: 60px;

    --radius-sm: 6px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 20px;
    --radius-full: 9999px;

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04), 0 1px 3px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 24px rgba(0,0,0,0.10);
    --shadow-xl: 0 16px 48px rgba(0,0,0,0.12);
    --shadow-primary: 0 8px 24px rgba(22,119,255,0.25);
    --shadow-accent: 0 8px 24px rgba(255,106,0,0.25);

    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);

    --container-max: 1200px;
    --header-height: 64px;
}

/* 全局重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    color: var(--color-text);
    line-height: 1.6;
    background: var(--color-bg);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-fast);
}

ul {
    list-style: none;
}

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

button {
    border: none;
    cursor: pointer;
    font-family: inherit;
    background: none;
}

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

/* 间距 */
.section-padding {
    padding: 80px 0;
}

.section-padding-gray {
    padding: 80px 0;
    background: var(--color-bg-gray);
}

/* 顶部公告栏 */
.top-bar {
    background: linear-gradient(90deg, #1D2129, #2A2F36);
    color: #C9CDD4;
    font-size: var(--font-size-xs);
    padding: 8px 0;
    position: relative;
    z-index: 100;
}

.top-bar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.top-bar-text {
    opacity: 0.9;
}

.top-bar-links {
    display: flex;
    align-items: center;
    gap: 8px;
}

.top-bar-links a {
    color: var(--color-primary-light);
    transition: var(--transition-fast);
}

.top-bar-links a:hover {
    color: #fff;
}

.top-bar .divider {
    color: #4E5969;
}

/* 导航栏 */
.header {
    position: fixed;
    top: 33px;
    left: 0;
    right: 0;
    height: var(--header-height);
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border-light);
    z-index: 99;
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: var(--shadow-sm);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-shrink: 0;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-text {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-text);
    display: flex;
    align-items: baseline;
    gap: 4px;
}

.logo-sub {
    font-size: var(--font-size-xs);
    font-weight: 400;
    color: var(--color-text-tertiary);
    margin-left: 4px;
}

/* 导航菜单 */
.nav-menu {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    border-radius: var(--radius-md);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--color-primary);
    background: var(--color-primary-bg);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 2px;
    background: var(--color-primary);
    border-radius: 1px;
}

.nav-cta {
    background: var(--color-primary);
    color: #fff !important;
    padding: 8px 20px;
    margin-left: 8px;
}

.nav-cta:hover {
    background: var(--color-primary-dark);
    color: #fff !important;
    box-shadow: var(--shadow-primary);
}

.nav-cta.active::after {
    display: none;
}

/* 移动端菜单按钮 */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 6px;
}

.mobile-menu-btn span {
    width: 24px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: var(--transition-fast);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}
.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}
.mobile-menu-btn.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* 按钮 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 24px;
    font-size: var(--font-size-sm);
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
    white-space: nowrap;
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background: var(--color-primary-dark);
    border-color: var(--color-primary-dark);
    box-shadow: var(--shadow-primary);
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-outline:hover {
    background: var(--color-primary);
    color: #fff;
    transform: translateY(-1px);
}

.btn-lg {
    padding: 14px 32px;
    font-size: var(--font-size-base);
}

.btn-sm {
    padding: 6px 16px;
    font-size: var(--font-size-xs);
}

.btn-block {
    width: 100%;
}

/* 区块标题 */
.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-tag {
    display: inline-block;
    padding: 4px 14px;
    font-size: var(--font-size-xs);
    font-weight: 600;
    color: var(--color-primary);
    background: var(--color-primary-bg);
    border-radius: var(--radius-full);
    margin-bottom: 16px;
    letter-spacing: 0.5px;
}

.section-tag-light {
    color: rgba(255,255,255,0.9);
    background: rgba(255,255,255,0.15);
}

.section-title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 12px;
    line-height: 1.3;
}

.section-desc {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
}

/* ============ Hero ============ */
.hero {
    position: relative;
    padding-top: calc(33px + var(--header-height) + 40px);
    padding-bottom: 80px;
    overflow: hidden;
    background: linear-gradient(180deg, #F0F7FF 0%, #FFFFFF 100%);
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    overflow: hidden;
    z-index: 0;
}

.hero-orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.3;
    animation: floatOrb 8s ease-in-out infinite;
}

.orb1 {
    width: 500px;
    height: 500px;
    background: var(--color-primary);
    top: -100px;
    right: -100px;
}

.orb2 {
    width: 400px;
    height: 400px;
    background: var(--color-accent);
    bottom: -50px;
    left: -100px;
    animation-delay: 2s;
}

.orb3 {
    width: 300px;
    height: 300px;
    background: var(--color-success);
    top: 200px;
    left: 40%;
    animation-delay: 4s;
}

@keyframes floatOrb {
    0%, 100% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(20px, -30px) scale(1.05); }
}

.hero-container {
    position: relative;
    z-index: 1;
    display: flex;
    align-items: center;
    gap: 60px;
}

.hero-content {
    flex: 1;
    max-width: 580px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 16px;
    background: rgba(255,255,255,0.8);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: 24px;
    backdrop-filter: blur(10px);
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: var(--color-success);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.6; transform: scale(1.2); }
}

.hero-title {
    font-size: var(--font-size-6xl);
    font-weight: 800;
    line-height: 1.15;
    color: var(--color-text);
    margin-bottom: 20px;
    letter-spacing: -0.5px;
}

.gradient-text {
    background: linear-gradient(135deg, var(--color-primary), var(--color-success));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    line-height: 1.8;
    margin-bottom: 32px;
}

.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
}

/* 统计数据 */
.hero-stats {
    display: flex;
    gap: 32px;
    flex-wrap: wrap;
}

.stat-item {
    text-align: left;
}

.stat-number {
    font-size: var(--font-size-3xl);
    font-weight: 800;
    color: var(--color-primary);
    line-height: 1;
    margin-bottom: 4px;
}

.stat-label {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* Hero 可视化 */
.hero-visual {
    flex: 1;
    max-width: 500px;
    position: relative;
}

.hero-card {
    background: #fff;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-xl);
    overflow: hidden;
    border: 1px solid var(--color-border-light);
    transform: perspective(1000px) rotateY(-3deg) rotateX(2deg);
    transition: var(--transition);
}

.hero-card:hover {
    transform: perspective(1000px) rotateY(0) rotateX(0);
}

.card-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 20px;
    background: #FAFAFA;
    border-bottom: 1px solid var(--color-border-light);
}

.card-dots {
    display: flex;
    gap: 6px;
}

.card-dots span {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--color-text-light);
}

.card-dots span:nth-child(1) { background: #FF5F57; }
.card-dots span:nth-child(2) { background: #FEBC2E; }
.card-dots span:nth-child(3) { background: #28C840; }

.card-title {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    font-weight: 500;
}

.card-body {
    padding: 8px 0;
    max-height: 360px;
    overflow: hidden;
}

.mail-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    padding: 12px 20px;
    transition: var(--transition-fast);
    border-bottom: 1px solid var(--color-border-light);
    position: relative;
}

.mail-item:hover {
    background: #F7F9FC;
}

.mail-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: var(--font-size-sm);
    font-weight: 600;
    flex-shrink: 0;
}

.mail-info {
    flex: 1;
    min-width: 0;
}

.mail-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2px;
}

.mail-sender {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text);
}

.mail-time {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    flex-shrink: 0;
}

.mail-subject {
    font-size: var(--font-size-sm);
    color: var(--color-text);
    margin-bottom: 2px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.mail-preview {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.mail-badge {
    font-size: 10px;
    padding: 2px 8px;
    border-radius: var(--radius-full);
    background: var(--color-border);
    color: var(--color-text-tertiary);
    flex-shrink: 0;
    margin-top: 2px;
}

.mail-badge-unread {
    background: var(--color-danger);
    color: #fff;
}

.mail-item.mail-unread .mail-sender {
    color: var(--color-primary);
}

.card-footer {
    display: flex;
    align-items: center;
    gap: 24px;
    padding: 10px 20px;
    background: #FAFAFA;
    border-top: 1px solid var(--color-border-light);
}

.card-action {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    cursor: pointer;
    transition: var(--transition-fast);
}

.card-action:hover {
    color: var(--color-primary);
}

/* 浮动标签 */
.hero-float {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px 18px;
    background: #fff;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--color-border-light);
    animation: floatCard 3s ease-in-out infinite;
}

.hero-float-1 {
    top: 30px;
    left: -40px;
    animation-delay: 0s;
}

.hero-float-2 {
    bottom: 40px;
    right: -30px;
    animation-delay: 1.5s;
}

@keyframes floatCard {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

.float-icon {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.float-title {
    font-size: var(--font-size-sm);
    font-weight: 700;
    color: var(--color-text);
}

.float-desc {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* ============ 产品版本 ============ */
.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-bottom: 24px;
}

.product-card {
    background: #fff;
    border: 2px solid var(--color-border);
    border-radius: var(--radius-xl);
    padding: 36px 28px;
    transition: var(--transition);
    position: relative;
}

.product-card:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.product-card-featured {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-primary);
    background: linear-gradient(180deg, #FFFFFF 0%, #F0F7FF 100%);
}

.product-card-featured:hover {
    transform: translateY(-8px);
}

.product-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, var(--color-accent), var(--color-accent-dark));
    color: #fff;
    font-size: var(--font-size-xs);
    font-weight: 600;
    padding: 4px 16px;
    border-radius: var(--radius-full);
    white-space: nowrap;
    box-shadow: var(--shadow-accent);
}

.product-header {
    text-align: center;
    margin-bottom: 24px;
}

.product-name {
    font-size: var(--font-size-2xl);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 4px;
}

.product-target {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.product-price {
    text-align: center;
    margin-bottom: 28px;
    padding-bottom: 24px;
    border-bottom: 1px dashed var(--color-border);
}

.price-symbol {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-primary);
    vertical-align: top;
}

.price-amount {
    font-size: var(--font-size-5xl);
    font-weight: 800;
    color: var(--color-primary);
    line-height: 1;
}

.price-unit {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.product-features {
    margin-bottom: 28px;
}

.product-features li {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 0;
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

.check-icon {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: var(--color-primary-bg);
    flex-shrink: 0;
    position: relative;
}

.check-icon::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -60%) rotate(45deg);
    width: 4px;
    height: 8px;
    border-right: 2px solid var(--color-primary);
    border-bottom: 2px solid var(--color-primary);
}

.product-note {
    text-align: center;
    color: var(--color-text-tertiary);
    font-size: var(--font-size-xs);
    line-height: 2;
}

/* ============ 核心优势 ============ */
.advantage-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.advantage-card {
    text-align: center;
    padding: 32px 20px;
    background: #fff;
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
}

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

.advantage-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.advantage-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 8px;
}

.advantage-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ============ 功能特色 ============ */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    padding: 28px 24px;
    background: #fff;
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
}

.feature-card:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
    border-color: var(--color-primary);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    background: var(--color-primary-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    transition: var(--transition);
}

.feature-card:hover .feature-icon {
    background: var(--color-primary);
}

.feature-card:hover .feature-icon svg {
    stroke: #fff;
}

.feature-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 8px;
}

.feature-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ============ 钉邮协同 ============ */
.dingtalk-content {
    max-width: 900px;
    margin: 0 auto;
}

.dingtalk-comparison {
    display: grid;
    grid-template-columns: 1fr auto 1fr;
    gap: 16px;
    align-items: center;
    margin-bottom: 24px;
}

.comparison-item {
    background: #fff;
    border-radius: var(--radius-lg);
    padding: 24px;
    border: 1px solid var(--color-border-light);
}

.comparison-header {
    margin-bottom: 12px;
}

.comparison-before {
    opacity: 0.6;
}

.comparison-after {
    border: 2px solid var(--color-primary);
    background: var(--color-primary-bg);
}

.comparison-tag {
    display: inline-block;
    font-size: var(--font-size-xs);
    font-weight: 600;
    padding: 2px 12px;
    border-radius: var(--radius-full);
    background: var(--color-text-light);
    color: #fff;
    margin-bottom: 8px;
}

.comparison-tag-active {
    background: var(--color-primary);
}

.comparison-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 4px;
}

.comparison-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

.comparison-arrow {
    display: flex;
    align-items: center;
    justify-content: center;
}

/* ============ 管理功能 ============ */
.manage-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.manage-item {
    padding: 24px 20px;
    background: #fff;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
    text-align: center;
}

.manage-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.manage-icon {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 12px;
}

.manage-item h3 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 6px;
}

.manage-item p {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    line-height: 1.6;
}

/* ============ 服务保障 ============ */
.service-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.service-card {
    text-align: center;
    padding: 36px 24px;
    background: #fff;
    border-radius: var(--radius-xl);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
}

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

.service-icon {
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
}

.service-title {
    font-size: var(--font-size-lg);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 8px;
}

.service-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* ============ 资质认证 ============ */
.cert-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.cert-item {
    text-align: center;
    padding: 32px 16px;
    background: #fff;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    transition: var(--transition);
}

.cert-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.cert-icon {
    margin-bottom: 16px;
    display: flex;
    justify-content: center;
}

.cert-item h3 {
    font-size: var(--font-size-sm);
    font-weight: 600;
    color: var(--color-text);
    margin-bottom: 4px;
    line-height: 1.4;
}

.cert-item p {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
}

/* ============ 常见问题 ============ */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    border-radius: var(--radius-lg);
    border: 1px solid var(--color-border-light);
    margin-bottom: 12px;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item:hover {
    box-shadow: var(--shadow-sm);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 24px;
    font-size: var(--font-size-base);
    font-weight: 600;
    color: var(--color-text);
    cursor: pointer;
    transition: var(--transition-fast);
}

.faq-question:hover {
    background: #FAFAFA;
}

.faq-toggle {
    transition: var(--transition);
    flex-shrink: 0;
    color: var(--color-text-tertiary);
}

.faq-item.active .faq-toggle {
    transform: rotate(180deg);
    color: var(--color-primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease, padding 0.3s ease;
    padding: 0 24px;
}

.faq-item.active .faq-answer {
    max-height: 300px;
    padding: 0 24px 18px;
}

.faq-answer p {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: 1.8;
}

/* ============ 联系我们 ============ */
.contact {
    background: linear-gradient(135deg, #0B1A3A 0%, #152759 50%, #1B3A7A 100%);
    color: #fff;
    position: relative;
    overflow: hidden;
}

.contact::before {
    content: '';
    position: absolute;
    top: -50px;
    right: -50px;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(22,119,255,0.2), transparent 70%);
    border-radius: 50%;
}

.contact-wrapper {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.contact-title {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    margin-bottom: 12px;
    color: #fff;
}

.contact-desc {
    font-size: var(--font-size-lg);
    color: rgba(255,255,255,0.7);
    margin-bottom: 32px;
}

.contact-methods {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.contact-method {
    display: flex;
    align-items: center;
    gap: 14px;
}

.method-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    background: rgba(255,255,255,0.15);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.method-label {
    font-size: var(--font-size-xs);
    color: rgba(255,255,255,0.6);
    margin-bottom: 2px;
}

.method-value {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: #fff;
}

/* 联系表单 */
.contact-form-wrapper {
    position: relative;
}

.contact-form {
    background: #fff;
    border-radius: var(--radius-xl);
    padding: 36px;
    box-shadow: var(--shadow-xl);
}

.form-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: 24px;
    text-align: center;
}

.form-group {
    margin-bottom: 16px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.form-label {
    display: block;
    font-size: var(--font-size-sm);
    font-weight: 500;
    color: var(--color-text-secondary);
    margin-bottom: 6px;
}

.required {
    color: var(--color-danger);
}

.form-input {
    width: 100%;
    padding: 10px 14px;
    font-size: var(--font-size-sm);
    color: var(--color-text);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: #fff;
    font-family: inherit;
    transition: var(--transition-fast);
}

.form-input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-bg);
}

.form-input::placeholder {
    color: var(--color-text-light);
}

.form-textarea {
    resize: vertical;
    min-height: 72px;
}

select.form-input {
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M3 5l3 3 3-3' stroke='%2386909C' stroke-width='1.5' fill='none' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 14px center;
    padding-right: 32px;
}

.form-note {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    text-align: center;
    margin-top: 12px;
}

.form-success {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: #fff;
    border-radius: var(--radius-xl);
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 40px;
}

.form-success.show {
    display: flex;
}

.success-icon {
    margin-bottom: 20px;
    animation: successPop 0.5s ease;
}

@keyframes successPop {
    0% { transform: scale(0); opacity: 0; }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); opacity: 1; }
}

.form-success h3 {
    font-size: var(--font-size-xl);
    color: var(--color-text);
    margin-bottom: 8px;
}

.form-success p {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    margin-bottom: 24px;
}

/* ============ 页脚 ============ */
.footer {
    background: #0F1419;
    color: #C9CDD4;
    padding: 60px 0 24px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.logo-footer .logo-text {
    color: #fff;
}

.logo-footer .logo-sub {
    color: #86909C;
}

.footer-desc {
    font-size: var(--font-size-sm);
    color: #86909C;
    line-height: 1.7;
    margin-top: 16px;
    max-width: 320px;
}

.footer-title {
    font-size: var(--font-size-base);
    font-weight: 600;
    color: #fff;
    margin-bottom: 16px;
}

.footer-links li {
    margin-bottom: 10px;
    font-size: var(--font-size-sm);
    color: #86909C;
}

.footer-links a {
    color: #86909C;
    transition: var(--transition-fast);
}

.footer-links a:hover {
    color: #fff;
}

.footer-social {
    display: flex;
    gap: 12px;
    margin-top: 16px;
}

.social-link {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: rgba(255,255,255,0.08);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #C9CDD4;
    transition: var(--transition-fast);
}

.social-link:hover {
    background: var(--color-primary);
    color: #fff;
    transform: translateY(-2px);
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.08);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    font-size: var(--font-size-xs);
    color: #86909C;
    margin-bottom: 4px;
}

/* ============ 返回顶部 ============ */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-primary);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 50;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
}

/* ============ 动画 ============ */
.fade-in-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

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

/* ============ 响应式 ============ */
@media (max-width: 1024px) {
    .hero-title {
        font-size: var(--font-size-5xl);
    }

    .product-grid,
    .advantage-grid,
    .manage-grid,
    .cert-grid {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

@media (max-width: 768px) {
    .top-bar-text {
        font-size: 11px;
    }

    .top-bar-links a {
        font-size: 11px;
    }

    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: #fff;
        flex-direction: column;
        padding: 16px;
        box-shadow: var(--shadow-lg);
        gap: 4px;
    }

    .nav-menu.active {
        display: flex;
    }

    .nav-link {
        width: 100%;
        padding: 12px 16px;
    }

    .nav-link.active::after {
        display: none;
    }

    .nav-cta {
        margin-left: 0;
        text-align: center;
    }

    .mobile-menu-btn {
        display: flex;
    }

    .hero {
        padding-top: calc(33px + var(--header-height) + 24px);
    }

    .hero-container {
        flex-direction: column;
        gap: 40px;
    }

    .hero-content,
    .hero-visual {
        max-width: 100%;
    }

    .hero-title {
        font-size: var(--font-size-4xl);
    }

    .hero-desc {
        font-size: var(--font-size-base);
    }

    .hero-actions {
        flex-direction: column;
    }

    .hero-actions .btn {
        width: 100%;
    }

    .hero-stats {
        gap: 20px;
    }

    .stat-number {
        font-size: var(--font-size-2xl);
    }

    .hero-float {
        display: none;
    }

    .section-title {
        font-size: var(--font-size-3xl);
    }

    .section-padding,
    .section-padding-gray {
        padding: 48px 0;
    }

    .product-grid,
    .advantage-grid,
    .manage-grid,
    .cert-grid,
    .feature-grid,
    .service-grid {
        grid-template-columns: 1fr;
    }

    .dingtalk-comparison {
        grid-template-columns: 1fr;
    }

    .comparison-arrow {
        transform: rotate(90deg);
        padding: 4px 0;
    }

    .contact-wrapper {
        grid-template-columns: 1fr;
        gap: 40px;
    }

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

    .form-row {
        grid-template-columns: 1fr;
    }

    .back-to-top {
        width: 40px;
        height: 40px;
        bottom: 20px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }

    .hero-title {
        font-size: var(--font-size-3xl);
    }

    .section-title {
        font-size: var(--font-size-2xl);
    }

    .top-bar .container {
        flex-direction: column;
        gap: 4px;
    }

    .hero-stats {
        flex-direction: column;
        gap: 16px;
    }

    .contact-form {
        padding: 24px;
    }
}