/* ========================================
   微载 (WeiZai) - 品牌样式表
   ======================================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: #333;
    line-height: 1.6;
    background: #fff;
    -webkit-font-smoothing: antialiased;
}

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

ul { list-style: none; }

img { max-width: 100%; height: auto; }

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* --- 品牌色板 --- */
:root {
    --primary: #07C160;
    --primary-dark: #06AD54;
    --primary-light: #E8F5E9;
    --secondary: #F5F5F5;
    --accent: #1A73E8;
    --text-primary: #333;
    --text-secondary: #666;
    --text-muted: #999;
    --border: #e5e5e5;
    --white: #fff;
    --shadow: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-hover: 0 8px 30px rgba(0,0,0,0.12);
    --radius: 12px;
    --radius-sm: 8px;
    --transition: all 0.3s ease;
}

/* --- 导航栏 --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

.navbar-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo-link {
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    width: 32px;
    height: 32px;
}

.logo-text {
    font-weight: 700;
    font-size: 20px;
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 32px;
}

.nav-links a {
    font-size: 15px;
    font-weight: 500;
    color: var(--text-secondary);
    transition: var(--transition);
    position: relative;
    padding: 4px 0;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
}

.nav-links a.active::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary);
    border-radius: 1px;
}

.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-btn span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    border-radius: 1px;
    transition: var(--transition);
}

/* --- Hero 区域 --- */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, var(--primary-light) 0%, #fff 50%, var(--primary-light) 100%);
    min-height: 80vh;
    display: flex;
    align-items: center;
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
}

.hero-content {
    flex: 1;
    max-width: 600px;
}

.hero-logo {
    width: 200px;
    margin-bottom: 24px;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.2;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 32px;
}

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

.hero-image {
    flex: 1;
    max-width: 500px;
    display: flex;
    justify-content: center;
}

.hero-illustration {
    width: 100%;
    max-width: 400px;
}

/* --- 按钮 --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    border-radius: var(--radius);
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    text-align: center;
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

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

.btn-secondary:hover {
    background: var(--primary);
    color: var(--white);
    transform: translateY(-2px);
}

/* --- 通用标题 --- */
.section-title {
    font-size: 36px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 16px;
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 48px;
}

/* --- 特性区域 --- */
.features {
    padding: 80px 0;
    background: var(--white);
}

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

.feature-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 24px;
    text-align: center;
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary);
}

.feature-icon {
    margin-bottom: 20px;
}

.feature-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.feature-desc {
    font-size: 14px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* --- 下载区域 --- */
.download {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-light) 0%, #fff 100%);
}

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

.download-card {
    background: var(--white);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 24px;
    text-align: center;
    transition: var(--transition);
}

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

.download-icon {
    margin-bottom: 20px;
}

.download-title {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-primary);
}

.download-version {
    font-size: 14px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.download-size {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.download-btn {
    width: 100%;
    padding: 12px 20px;
    font-size: 14px;
}

/* --- FAQ 区域 --- */
.faq {
    padding: 80px 0;
    background: var(--white);
}

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

.faq-item {
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 12px;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item:hover {
    border-color: var(--primary);
}

.faq-question {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    background: none;
    border: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    color: var(--text-primary);
    text-align: left;
    transition: var(--transition);
}

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

.faq-arrow {
    transition: transform 0.3s ease;
    flex-shrink: 0;
}

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

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

.faq-item.active .faq-answer {
    max-height: 300px;
    padding: 0 24px 20px;
}

.faq-answer p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* --- 页脚 --- */
.footer {
    background: #1a1a2e;
    color: #ccc;
    padding: 60px 0 0;
}

.footer-inner {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr;
    gap: 40px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-logo {
    width: 160px;
    margin-bottom: 16px;
    filter: brightness(0) invert(1);
}

.footer-desc {
    font-size: 14px;
    line-height: 1.6;
    color: #999;
}

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

.footer-links a {
    display: block;
    font-size: 14px;
    color: #999;
    margin-bottom: 8px;
    transition: var(--transition);
}

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

.footer-contact p {
    font-size: 14px;
    color: #999;
    margin-bottom: 8px;
}

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

.footer-social a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255,255,255,0.1);
    border-radius: 50%;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding: 20px 0;
    font-size: 13px;
    color: #666;
}

/* --- 页面 Hero (关于/联系) --- */
.page-hero {
    padding: 120px 0 60px;
    background: linear-gradient(135deg, var(--primary-light) 0%, #fff 100%);
    text-align: center;
}

.page-title {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.page-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
}

/* --- 关于页 - 品牌故事 --- */
.story {
    padding: 80px 0;
    background: var(--white);
}

.story-content {
    max-width: 800px;
    margin: 0 auto;
}

.story-content p {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 20px;
}

/* --- 使命愿景 --- */
.mission {
    padding: 60px 0;
    background: var(--primary-light);
}

.mission-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.mission-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 32px 24px;
    box-shadow: var(--shadow);
}

.mission-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--primary);
}

.mission-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.mission-card ul {
    padding-left: 20px;
}

.mission-card ul li {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.8;
    list-style: disc;
}

/* --- 团队介绍 --- */
.team {
    padding: 80px 0;
    background: var(--white);
}

.team-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    max-width: 900px;
    margin: 0 auto;
}

.team-card {
    text-align: center;
    padding: 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    transition: var(--transition);
}

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

.team-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
    font-size: 32px;
    font-weight: 700;
    color: var(--primary);
}

.team-name {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--text-primary);
}

.team-role {
    font-size: 13px;
    color: var(--text-muted);
}

/* --- 数据统计 --- */
.stats {
    padding: 60px 0;
    background: var(--primary);
    color: var(--white);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    text-align: center;
}

.stat-number {
    font-size: 36px;
    font-weight: 700;
    display: block;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 16px;
    opacity: 0.9;
}

/* --- 联系页 --- */
.contact-section {
    padding: 80px 0;
    background: var(--white);
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
}

.contact-info .section-title {
    text-align: left;
    margin-bottom: 32px;
}

.contact-item {
    margin-bottom: 24px;
}

.contact-item h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 4px;
}

.contact-item p {
    font-size: 16px;
    color: var(--text-primary);
}

.contact-social h4 {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 12px;
}

.social-links {
    display: flex;
    gap: 12px;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    background: var(--primary-light);
    border-radius: 50%;
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--primary);
    transform: translateY(-2px);
}

/* --- 联系表单 --- */
.contact-form-wrapper .section-title {
    text-align: left;
    margin-bottom: 32px;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-family: inherit;
    transition: var(--transition);
    background: var(--white);
}

.form-group input:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(7,193,96,0.1);
}

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

/* --- Toast 通知 --- */
.toast {
    position: fixed;
    top: 80px;
    right: 20px;
    background: var(--primary);
    color: var(--white);
    padding: 16px 24px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    font-size: 14px;
    z-index: 9999;
    opacity: 0;
    transform: translateX(100%);
    transition: all 0.3s ease;
}

.toast.show {
    opacity: 1;
    transform: translateX(0);
}

.toast.error {
    background: #e74c3c;
}

/* --- 响应式设计 --- */
@media (max-width: 1024px) {
    .features-grid,
    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .team-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .hero .container {
        flex-direction: column;
        text-align: center;
    }
    
    .hero-content {
        max-width: 100%;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-image {
        display: none;
    }
    
    .hero-title {
        font-size: 36px;
    }
}

@media (max-width: 768px) {
    .navbar-inner {
        height: 56px;
    }
    
    .nav-links {
        display: none;
        position: fixed;
        top: 56px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        gap: 16px;
        box-shadow: 0 4px 20px rgba(0,0,0,0.1);
        border-bottom: 1px solid var(--border);
    }
    
    .nav-links.open {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .hero {
        padding: 100px 0 60px;
        min-height: auto;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .features-grid,
    .download-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-inner {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-links a {
        text-align: center;
    }
    
    .footer-social {
        justify-content: center;
    }
    
    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 16px;
    }
    
    .stat-number {
        font-size: 28px;
    }
    
    .mission-grid {
        grid-template-columns: 1fr;
    }
    
    .team-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    
    .page-title {
        font-size: 32px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    
    .hero-title {
        font-size: 24px;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 14px;
    }
    
    .team-grid {
        grid-template-columns: 1fr;
    }
}