/* ============================================================
   style.css - 寰钢集团有限公司 品牌官网样式表
   版本: 1.0
   说明: 移动优先，纯CSS装饰，零图片依赖
   ============================================================ */

/* ---------- CSS 变量 (设计令牌) ---------- */
:root {
    /* 品牌色 */
    --color-primary: #1A3A5C;
    --color-primary-light: #2A5A7C;
    --color-primary-dark: #0F2A3F;
    --color-secondary: #C9A84C;
    --color-secondary-light: #DBC06A;
    --color-secondary-dark: #B08F3A;
    --color-accent: #E67E22;
    --color-accent-light: #F09A4A;
    --color-accent-dark: #CF6A1A;

    /* 中性色 */
    --color-white: #FFFFFF;
    --color-off-white: #F5F7FA;
    --color-gray-100: #EEF1F5;
    --color-gray-200: #DCE1E8;
    --color-gray-300: #B8C2CC;
    --color-gray-400: #8E9AA8;
    --color-gray-500: #6A7A8A;
    --color-gray-600: #4A5A6A;
    --color-gray-700: #2E3E4E;
    --color-gray-800: #1E2E3E;
    --color-gray-900: #0F1A2A;
    --color-black: #0A0F18;

    /* 字体 */
    --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

    /* 字号 */
    --font-size-h1: 2.2rem;
    --font-size-h2: 1.8rem;
    --font-size-h3: 1.4rem;
    --font-size-h4: 1.2rem;
    --font-size-body: 1rem;
    --font-size-small: 0.9rem;
    --font-size-xs: 0.8rem;

    /* 间距 */
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 40px;
    --spacing-xl: 60px;
    --spacing-xxl: 80px;
    --spacing-xxxl: 100px;

    /* 圆角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(26, 58, 92, 0.08);
    --shadow-md: 0 4px 20px rgba(26, 58, 92, 0.12);
    --shadow-lg: 0 8px 40px rgba(26, 58, 92, 0.18);
    --shadow-xl: 0 16px 60px rgba(26, 58, 92, 0.25);

    /* 过渡 */
    --transition-fast: 0.2s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;

    /* 容器宽度 */
    --container-max: 1200px;
    --container-padding: 20px;
}

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

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-family);
    font-size: var(--font-size-body);
    line-height: 1.6;
    color: var(--color-gray-800);
    background-color: var(--color-white);
    overflow-x: hidden;
}

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

/* ---------- 标题层级 ---------- */
h1 {
    font-size: var(--font-size-h1);
    font-weight: 700;
    line-height: 1.2;
    color: var(--color-primary);
    letter-spacing: -0.02em;
}

h2 {
    font-size: var(--font-size-h2);
    font-weight: 700;
    line-height: 1.25;
    color: var(--color-primary);
    letter-spacing: -0.01em;
    margin-bottom: var(--spacing-md);
}

h3 {
    font-size: var(--font-size-h3);
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

h4 {
    font-size: var(--font-size-h4);
    font-weight: 600;
    line-height: 1.4;
    color: var(--color-primary);
}

p {
    font-size: var(--font-size-body);
    line-height: 1.7;
    color: var(--color-gray-600);
    margin-bottom: var(--spacing-sm);
}

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

a:hover {
    color: var(--color-secondary);
}

/* ---------- 按钮基础 (三合一效果) ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: 12px 28px;
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 600;
    line-height: 1.2;
    text-align: center;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-full);
    cursor: pointer;
    transition: all var(--transition-base);
    position: relative;
    overflow: hidden;
    min-height: 48px;
}

/* 按钮三合一效果：颜色渐变 + 发光阴影 + scale 1.03 */
.btn-primary {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark));
    color: var(--color-white);
    box-shadow: 0 4px 16px rgba(201, 168, 76, 0.35);
}

.btn-primary:hover {
    background: linear-gradient(135deg, var(--color-secondary-light), var(--color-secondary));
    box-shadow: 0 8px 32px rgba(201, 168, 76, 0.5), 0 0 0 2px rgba(201, 168, 76, 0.2);
    transform: scale(1.03);
    color: var(--color-white);
}

.btn-primary:active {
    transform: scale(0.97);
    box-shadow: 0 2px 8px rgba(201, 168, 76, 0.3);
}

.btn-secondary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    color: var(--color-white);
    box-shadow: 0 4px 16px rgba(26, 58, 92, 0.3);
}

.btn-secondary:hover {
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
    box-shadow: 0 8px 32px rgba(26, 58, 92, 0.45), 0 0 0 2px rgba(26, 58, 92, 0.15);
    transform: scale(1.03);
    color: var(--color-white);
}

.btn-secondary:active {
    transform: scale(0.97);
    box-shadow: 0 2px 8px rgba(26, 58, 92, 0.25);
}

.btn-accent {
    background: linear-gradient(135deg, var(--color-accent), var(--color-accent-dark));
    color: var(--color-white);
    box-shadow: 0 4px 16px rgba(230, 126, 34, 0.35);
}

.btn-accent:hover {
    background: linear-gradient(135deg, var(--color-accent-light), var(--color-accent));
    box-shadow: 0 8px 32px rgba(230, 126, 34, 0.5), 0 0 0 2px rgba(230, 126, 34, 0.2);
    transform: scale(1.03);
    color: var(--color-white);
}

.btn-accent:active {
    transform: scale(0.97);
    box-shadow: 0 2px 8px rgba(230, 126, 34, 0.3);
}

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
    box-shadow: none;
}

.btn-outline:hover {
    background: var(--color-primary);
    color: var(--color-white);
    box-shadow: 0 8px 32px rgba(26, 58, 92, 0.3);
    transform: scale(1.03);
}

.btn-outline:active {
    transform: scale(0.97);
}

/* ---------- 区块通用 ---------- */
.section {
    padding: var(--spacing-xxl) 0;
}

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

.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto var(--spacing-xl);
}

.section-header h2 {
    margin-bottom: var(--spacing-sm);
}

.section-header p {
    font-size: 1.1rem;
    color: var(--color-gray-500);
}

/* ---------- 1. 导航栏 (Sticky + 毛玻璃) ---------- */
.header {
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 12px 0;
    background: rgba(255, 255, 255, 0.75);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 2px 20px rgba(26, 58, 92, 0.06);
    transition: background var(--transition-base);
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-sm);
}

/* Logo */
.logo {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--color-primary);
    letter-spacing: -0.02em;
    flex-shrink: 0;
}

.logo-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    border-radius: var(--radius-sm);
    color: var(--color-white);
    font-weight: 800;
    font-size: 0.9rem;
    letter-spacing: 0;
}

.logo .highlight {
    color: var(--color-secondary);
}

/* 导航菜单 (桌面) */
.nav-menu {
    display: none;
    align-items: center;
    gap: var(--spacing-md);
    list-style: none;
}

.nav-menu a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--color-gray-700);
    padding: 6px 4px;
    position: relative;
    transition: color var(--transition-fast);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-secondary);
    transition: width var(--transition-base);
}

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

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

.nav-menu .btn {
    margin-left: var(--spacing-sm);
    padding: 8px 20px;
    font-size: 0.9rem;
    min-height: 40px;
}

/* 汉堡按钮 */
.hamburger {
    display: flex;
    flex-direction: column;
    gap: 5px;
    padding: 6px;
    background: none;
    border: none;
    cursor: pointer;
    width: 36px;
    height: 36px;
    justify-content: center;
    align-items: center;
    border-radius: var(--radius-sm);
    transition: background var(--transition-fast);
}

.hamburger:hover {
    background: rgba(26, 58, 92, 0.06);
}

.hamburger span {
    display: block;
    width: 24px;
    height: 2.5px;
    background: var(--color-primary);
    border-radius: 2px;
    transition: all var(--transition-base);
    transform-origin: center;
}

.hamburger.active span:nth-child(1) {
    transform: translateY(7.5px) rotate(45deg);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0);
}

.hamburger.active span:nth-child(3) {
    transform: translateY(-7.5px) rotate(-45deg);
}

/* 移动端下拉菜单 */
.nav-dropdown {
    display: none;
    flex-direction: column;
    gap: 4px;
    padding: var(--spacing-sm) 0;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    border-top: 1px solid var(--color-gray-100);
    box-shadow: 0 8px 32px rgba(26, 58, 92, 0.1);
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    transform: translateY(-8px);
    opacity: 0;
    transition: all var(--transition-base);
    pointer-events: none;
}

.nav-dropdown.open {
    display: flex;
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
}

.nav-dropdown a {
    padding: 12px var(--container-padding);
    font-size: 1rem;
    font-weight: 500;
    color: var(--color-gray-700);
    transition: all var(--transition-fast);
    border-left: 3px solid transparent;
}

.nav-dropdown a:hover {
    background: var(--color-off-white);
    color: var(--color-primary);
    border-left-color: var(--color-secondary);
}

.nav-dropdown .btn {
    margin: 8px var(--container-padding) 4px;
    justify-content: center;
}

/* ---------- 2. 英雄区 (Hero) ---------- */
#hero {
    position: relative;
    padding: var(--spacing-xl) 0 var(--spacing-xxl);
    background: linear-gradient(160deg, #f0f4fa 0%, #e8edf5 40%, #dce3ed 100%);
    overflow: hidden;
    min-height: 500px;
    display: flex;
    align-items: center;
}

#hero .container {
    position: relative;
    z-index: 2;
}

/* 几何装饰 - 动态旋转 */
.hero-deco {
    position: absolute;
    border-radius: 50%;
    opacity: 0.12;
    pointer-events: none;
}

.hero-deco-1 {
    width: 320px;
    height: 320px;
    background: radial-gradient(circle, var(--color-secondary), transparent 70%);
    top: -80px;
    right: -60px;
    animation: spin-slow 40s linear infinite;
}

.hero-deco-2 {
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, var(--color-primary), transparent 70%);
    bottom: -40px;
    left: -60px;
    animation: spin-slow 30s linear infinite reverse;
}

.hero-deco-3 {
    width: 120px;
    height: 120px;
    background: radial-gradient(circle, var(--color-accent), transparent 70%);
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation: spin-slow 50s linear infinite;
    opacity: 0.06;
}

@keyframes spin-slow {
    0% {
        transform: rotate(0deg) scale(1);
    }
    50% {
        transform: rotate(180deg) scale(1.1);
    }
    100% {
        transform: rotate(360deg) scale(1);
    }
}

/* 多边形装饰 (CSS clip-path) */
.hero-polygon {
    position: absolute;
    width: 180px;
    height: 180px;
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-light));
    clip-path: polygon(50% 0%, 0% 100%, 100% 100%);
    opacity: 0.08;
    right: 10%;
    bottom: 10%;
    animation: float-polygon 6s ease-in-out infinite;
}

@keyframes float-polygon {
    0%,
    100% {
        transform: translateY(0) rotate(0deg);
    }
    50% {
        transform: translateY(-20px) rotate(5deg);
    }
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 640px;
}

.hero-content h1 {
    font-size: 2.4rem;
    margin-bottom: var(--spacing-sm);
}

.hero-content h1 .highlight {
    color: var(--color-secondary);
}

.hero-content .subtitle {
    font-size: 1.15rem;
    color: var(--color-gray-500);
    margin-bottom: var(--spacing-lg);
    max-width: 480px;
}

.hero-content .btn {
    font-size: 1.05rem;
    padding: 14px 36px;
}

/* ---------- 3. 痛点与情境 (Pain Points) ---------- */
#pain-points {
    background: var(--color-white);
}

.pain-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.pain-item {
    display: flex;
    gap: var(--spacing-md);
    padding: var(--spacing-md);
    background: var(--color-off-white);
    border-radius: var(--radius-md);
    border-left: 4px solid var(--color-secondary);
    transition: all var(--transition-base);
}

.pain-item:hover {
    transform: translateX(6px);
    box-shadow: var(--shadow-sm);
}

.pain-icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(201, 168, 76, 0.12);
    border-radius: var(--radius-sm);
    color: var(--color-secondary);
    font-size: 1.4rem;
    font-weight: 700;
}

.pain-text h4 {
    font-size: 1rem;
    margin-bottom: 4px;
}

.pain-text p {
    font-size: 0.95rem;
    color: var(--color-gray-500);
    margin-bottom: 0;
}

/* ---------- 4. 解决方案 (Solutions) ---------- */
#solutions {
    background: var(--color-off-white);
}

.solution-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
}

.solution-card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    border-top: 4px solid var(--color-secondary);
    transition: all var(--transition-base);
}

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

.solution-card .icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    color: var(--color-white);
    border-radius: var(--radius-sm);
    font-size: 1.6rem;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.solution-card h3 {
    font-size: 1.2rem;
    margin-bottom: var(--spacing-xs);
}

.solution-card p {
    font-size: 0.95rem;
    color: var(--color-gray-500);
    margin-bottom: var(--spacing-sm);
}

.solution-card ul {
    list-style: none;
    padding: 0;
}

.solution-card ul li {
    font-size: 0.9rem;
    color: var(--color-gray-600);
    padding: 4px 0;
    padding-left: 20px;
    position: relative;
}

.solution-card ul li::before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--color-secondary);
    font-weight: 700;
}

/* ---------- 5. 信任背书 (Testimonials) ---------- */
#testimonials {
    background: var(--color-white);
}

.testimonial-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
}

.testimonial-card {
    background: var(--color-off-white);
    border-radius: var(--radius-md);
    padding: var(--spacing-md);
    border: 1px solid var(--color-gray-100);
    transition: all var(--transition-base);
}

.testimonial-card:hover {
    box-shadow: var(--shadow-sm);
    transform: translateY(-2px);
}

.testimonial-card .quote {
    font-size: 0.95rem;
    color: var(--color-gray-600);
    font-style: italic;
    margin-bottom: var(--spacing-sm);
    padding-left: 16px;
    border-left: 3px solid var(--color-secondary);
}

.testimonial-card .author {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.testimonial-card .avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: var(--color-white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1.1rem;
    flex-shrink: 0;
}

.testimonial-card .author-info {
    font-size: 0.9rem;
}

.testimonial-card .author-info .name {
    font-weight: 600;
    color: var(--color-primary);
}

.testimonial-card .author-info .role {
    color: var(--color-gray-500);
    font-size: 0.85rem;
}

/* 认证徽章 */
.badge-grid {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    justify-content: center;
    margin-top: var(--spacing-lg);
    padding-top: var(--spacing-lg);
    border-top: 1px solid var(--color-gray-100);
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: var(--color-off-white);
    border: 1px solid var(--color-gray-200);
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-gray-700);
}

.badge .badge-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    background: var(--color-primary);
    color: var(--color-white);
    border-radius: 50%;
    font-size: 0.7rem;
    font-weight: 700;
}

/* 数据统计 */
.stats-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-top: var(--spacing-lg);
    text-align: center;
}

.stat-item .number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--color-secondary);
    display: block;
}

.stat-item .label {
    font-size: 0.9rem;
    color: var(--color-gray-500);
}

/* ---------- 6. 关于我们 (About) ---------- */
#about {
    background: var(--color-off-white);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
}

.about-content p {
    font-size: 1rem;
    line-height: 1.8;
    color: var(--color-gray-600);
}

.about-content .highlight-text {
    color: var(--color-secondary);
    font-weight: 600;
}

.about-info {
    background: var(--color-white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
}

.about-info address {
    font-style: normal;
    line-height: 1.8;
    color: var(--color-gray-600);
}

.about-info address strong {
    color: var(--color-primary);
    display: inline-block;
    min-width: 80px;
}

.about-info .contact-item {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    padding: 8px 0;
    border-bottom: 1px solid var(--color-gray-100);
}

.about-info .contact-item:last-child {
    border-bottom: none;
}

.about-info .contact-item .label {
    font-weight: 600;
    color: var(--color-primary);
    min-width: 80px;
    flex-shrink: 0;
}

/* ---------- 7. 常见问题 (FAQ) ---------- */
#faq {
    background: var(--color-white);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid var(--color-gray-100);
    padding: var(--spacing-sm) 0;
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-question {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--spacing-sm);
    width: 100%;
    padding: 12px 0;
    background: none;
    border: none;
    font-family: var(--font-family);
    font-size: 1rem;
    font-weight: 600;
    color: var(--color-primary);
    text-align: left;
    cursor: pointer;
    transition: color var(--transition-fast);
    line-height: 1.4;
}

.faq-question:hover {
    color: var(--color-secondary);
}

.faq-question .icon {
    flex-shrink: 0;
    font-size: 1.2rem;
    color: var(--color-secondary);
    transition: transform var(--transition-base);
    font-weight: 300;
}

.faq-item.active .faq-question .icon {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-slow), padding var(--transition-base);
    padding: 0 0 0 0;
}

.faq-item.active .faq-answer {
    max-height: 400px;
    padding: 0 0 var(--spacing-sm) 0;
}

.faq-answer p {
    font-size: 0.95rem;
    color: var(--color-gray-500);
    margin-bottom: 0;
    line-height: 1.7;
}

/* ---------- 8. 终极呼吁 (Contact) ---------- */
#contact {
    background: linear-gradient(160deg, var(--color-primary), var(--color-primary-dark));
    color: var(--color-white);
}

#contact .section-header h2 {
    color: var(--color-white);
}

#contact .section-header p {
    color: rgba(255, 255, 255, 0.7);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.contact-form {
    background: rgba(255, 255, 255, 0.06);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.contact-form .form-group {
    margin-bottom: var(--spacing-md);
}

.contact-form label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 4px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 12px 16px;
    font-family: var(--font-family);
    font-size: 1rem;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-sm);
    color: var(--color-white);
    transition: all var(--transition-fast);
    outline: none;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: rgba(255, 255, 255, 0.4);
}

.contact-form input:focus,
.contact-form textarea:focus {
    background: rgba(255, 255, 255, 0.12);
    border-color: var(--color-secondary);
    box-shadow: 0 0 0 3px rgba(201, 168, 76, 0.15);
}

.contact-form textarea {
    min-height: 120px;
    resize: vertical;
}

.contact-form .btn {
    width: 100%;
    justify-content: center;
    padding: 14px;
    font-size: 1.05rem;
}

.contact-info-side {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    padding: var(--spacing-sm) 0;
}

.contact-info-side .info-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 12px 16px;
    background: rgba(255, 255, 255, 0.06);
    border-radius: var(--radius-sm);
    border-left: 3px solid var(--color-secondary);
}

.contact-info-side .info-item .ico {
    font-size: 1.4rem;
    flex-shrink: 0;
    color: var(--color-secondary);
}

.contact-info-side .info-item .text {
    font-size: 0.95rem;
    color: rgba(255, 255, 255, 0.85);
}

.contact-info-side .info-item .text strong {
    color: var(--color-white);
}

.contact-info-side .quick-response {
    margin-top: var(--spacing-sm);
    padding: var(--spacing-md);
    background: rgba(201, 168, 76, 0.12);
    border-radius: var(--radius-sm);
    border: 1px dashed rgba(201, 168, 76, 0.3);
    text-align: center;
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.95rem;
}

.contact-info-side .quick-response strong {
    color: var(--color-secondary);
}

/* ---------- 9. 页脚 (Footer) ---------- */
.footer {
    background: var(--color-gray-900);
    color: rgba(255, 255, 255, 0.6);
    padding: var(--spacing-lg) 0 var(--spacing-sm);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--spacing-md);
    text-align: center;
}

.footer-brand .logo {
    color: var(--color-white);
    justify-content: center;
}

.footer-brand .logo .logo-icon {
    background: linear-gradient(135deg, var(--color-secondary), var(--color-secondary-dark));
}

.footer-brand p {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.5);
    margin-top: var(--spacing-xs);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--spacing-md);
}

.footer-links a {
    font-size: 0.9rem;
    color: rgba(255, 255, 255, 0.5);
    transition: color var(--transition-fast);
}

.footer-links a:hover {
    color: var(--color-secondary);
}

.footer-legal {
    font-size: 0.85rem;
    color: rgba(255, 255, 255, 0.35);
}

.footer-legal a {
    color: rgba(255, 255, 255, 0.35);
    transition: color var(--transition-fast);
}

.footer-legal a:hover {
    color: var(--color-secondary);
}

.footer-bottom {
    margin-top: var(--spacing-md);
    padding-top: var(--spacing-md);
    border-top: 1px solid rgba(255, 255, 255, 0.06);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    align-items: center;
    font-size: 0.8rem;
    color: rgba(255, 255, 255, 0.3);
}

.footer-bottom .disclaimer {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.2);
    font-style: italic;
}

/* ---------- 响应式: 平板 (≥768px) ---------- */
@media (min-width: 768px) {
    :root {
        --font-size-h1: 2.8rem;
        --font-size-h2: 2rem;
        --font-size-h3: 1.5rem;
        --container-padding: 40px;
    }

    /* 导航 */
    .hamburger {
        display: none;
    }

    .nav-menu {
        display: flex;
    }

    .nav-dropdown {
        display: none !important;
    }

    /* 痛点网格 */
    .pain-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    /* 解决方案网格 */
    .solution-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    /* 证言网格 */
    .testimonial-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    /* 统计行 */
    .stats-row {
        grid-template-columns: repeat(4, 1fr);
    }

    /* 关于 */
    .about-grid {
        grid-template-columns: 3fr 2fr;
        align-items: start;
    }

    /* 联系 */
    .contact-grid {
        grid-template-columns: 3fr 2fr;
        align-items: start;
    }

    /* 页脚 */
    .footer-grid {
        grid-template-columns: 2fr 1fr 1fr;
        text-align: left;
    }

    .footer-brand .logo {
        justify-content: flex-start;
    }

    .footer-links {
        justify-content: flex-start;
    }

    .footer-bottom {
        flex-direction: row;
        justify-content: space-between;
    }
}

/* ---------- 响应式: 桌面 (≥1024px) ---------- */
@media (min-width: 1024px) {
    :root {
        --font-size-h1: 3.2rem;
        --font-size-h2: 2.2rem;
        --font-size-h3: 1.6rem;
        --container-padding: 60px;
    }

    .section {
        padding: var(--spacing-xxxl) 0;
    }

    /* 英雄区 */
    #hero {
        min-height: 600px;
        padding: var(--spacing-xxl) 0 var(--spacing-xxxl);
    }

    .hero-content h1 {
        font-size: 3.2rem;
    }

    .hero-content .subtitle {
        font-size: 1.25rem;
    }

    /* 解决方案网格 - 桌面4列 */
    .solution-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    /* 证言网格 - 桌面3列 */
    .testimonial-grid {
        grid-template-columns: repeat(3, 1fr);
    }

    /* 痛点网格 - 桌面4列 */
    .pain-grid {
        grid-template-columns: repeat(4, 1fr);
    }

    /* 几何装饰更大 */
    .hero-deco-1 {
        width: 480px;
        height: 480px;
        top: -120px;
        right: -80px;
    }

    .hero-deco-2 {
        width: 300px;
        height: 300px;
        bottom: -60px;
        left: -80px;
    }

    .hero-deco-3 {
        width: 200px;
        height: 200px;
    }

    .hero-polygon {
        width: 280px;
        height: 280px;
    }
}

/* ---------- 辅助工具 ---------- */
.text-center {
    text-align: center;
}

.text-secondary {
    color: var(--color-secondary);
}

.text-accent {
    color: var(--color-accent);
}

.mt-1 {
    margin-top: var(--spacing-sm);
}
.mt-2 {
    margin-top: var(--spacing-md);
}
.mt-3 {
    margin-top: var(--spacing-lg);
}

.mb-1 {
    margin-bottom: var(--spacing-sm);
}
.mb-2 {
    margin-bottom: var(--spacing-md);
}
.mb-3 {
    margin-bottom: var(--spacing-lg);
}

/* ---------- 滚动条美化 ---------- */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-gray-100);
}

::-webkit-scrollbar-thumb {
    background: var(--color-secondary);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-secondary-dark);
}

/* ---------- 选择高亮 ---------- */
::selection {
    background: var(--color-secondary);
    color: var(--color-white);
}

/* ---------- 打印优化 ---------- */
@media print {
    .header {
        position: static;
        backdrop-filter: none;
        background: var(--color-white);
    }

    .hero-deco,
    .hero-polygon {
        display: none;
    }

    .btn {
        background: var(--color-primary) !important;
        color: var(--color-white) !important;
        box-shadow: none !important;
        transform: none !important;
    }

    .nav-dropdown {
        display: none !important;
    }

    .hamburger {
        display: none !important;
    }

    .nav-menu {
        display: flex !important;
    }

    .section {
        padding: var(--spacing-lg) 0;
        page-break-inside: avoid;
    }

    #contact {
        background: var(--color-white) !important;
        color: var(--color-gray-800) !important;
    }

    #contact .section-header h2 {
        color: var(--color-primary) !important;
    }

    .contact-form {
        background: var(--color-gray-100) !important;
        border: 1px solid var(--color-gray-200) !important;
    }

    .contact-form input,
    .contact-form textarea {
        background: var(--color-white) !important;
        color: var(--color-gray-800) !important;
        border-color: var(--color-gray-200) !important;
    }

    .contact-info-side .info-item {
        background: var(--color-gray-100) !important;
        color: var(--color-gray-800) !important;
    }

    .contact-info-side .info-item .text {
        color: var(--color-gray-800) !important;
    }

    .footer {
        background: var(--color-gray-800) !important;
    }

    .footer-grid .logo {
        color: var(--color-white) !important;
    }
}