/* 全局样式 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --secondary-color: #f59e0b;
    --accent-color: #10b981;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --border-radius: 12px;
    --border-radius-lg: 16px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    overflow-x: hidden;
}

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

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    z-index: 1000;
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.nav-logo i {
    font-size: 1.8rem;
}

.nav-menu {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-primary);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

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

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: var(--text-primary);
    margin: 3px 0;
    transition: var(--transition);
}

/* 主页横幅 */
.hero {
    padding: 120px 0 80px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="grain" width="100" height="100" patternUnits="userSpaceOnUse"><circle cx="50" cy="50" r="1" fill="white" opacity="0.1"/></pattern></defs><rect width="100" height="100" fill="url(%23grain)"/></svg>');
    opacity: 0.3;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    line-height: 1.6;
}

.hero-stats {
    display: flex;
    gap: 2rem;
    margin-bottom: 2.5rem;
}

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

.stat-number {
    display: block;
    font-size: 2rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

.cta-button {
    display: inline-block;
    background: var(--secondary-color);
    color: white;
    padding: 15px 30px;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    box-shadow: var(--shadow-lg);
}

.cta-button:hover {
    background: #d97706;
    transform: translateY(-2px);
    box-shadow: var(--shadow-xl);
}

.hero-image {
    display: flex;
    justify-content: center;
    align-items: center;
}

.floating-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: var(--border-radius-lg);
    padding: 2rem;
    text-align: center;
    animation: float 6s ease-in-out infinite;
}

.floating-card i {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: var(--secondary-color);
}

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

/* 优惠券区域 */
.coupons-section {
    padding: 80px 0;
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 3rem;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.section-header p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

.filter-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-tab {
    background: white;
    border: 2px solid var(--border-color);
    color: var(--text-secondary);
    padding: 12px 24px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
    font-weight: 500;
}

.filter-tab:hover,
.filter-tab.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.coupons-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.coupon-card {
    background: white;
    border-radius: var(--border-radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-md);
    transition: var(--transition);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.coupon-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
}

.coupon-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.coupon-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-bottom: 1.5rem;
}

.brand-logo {
    width: 60px;
    height: 60px;
    border-radius: 12px;
    object-fit: cover;
}

.coupon-info h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.25rem;
}

.coupon-info p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.coupon-content {
    margin-bottom: 1.5rem;
}

.discount {
    display: flex;
    align-items: baseline;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.discount-amount {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-color);
}

.discount-text {
    font-size: 1rem;
    color: var(--text-secondary);
}

.coupon-desc {
    color: var(--text-secondary);
    line-height: 1.5;
}

.claim-button {
    width: 100%;
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 12px;
    border-radius: var(--border-radius);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.claim-button:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}

/* 品牌展示 */
.brands-section {
    padding: 80px 0;
    background: white;
}

.brands-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.brand-item {
    text-align: center;
    padding: 2rem;
    border-radius: var(--border-radius);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.brand-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.brand-item img {
    width: 120px;
    height: 80px;
    border-radius: 8px;
    margin-bottom: 1rem;
    object-fit: cover;
}

.brand-item h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.brand-item p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* 使用指南 */
.guide-section {
    padding: 80px 0;
    background: var(--bg-secondary);
}

.guide-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.step {
    text-align: center;
    padding: 2rem;
    background: white;
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    transition: var(--transition);
}

.step:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-xl);
}

.step-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.step-icon i {
    font-size: 2rem;
    color: white;
}

.step h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.step p {
    color: var(--text-secondary);
    line-height: 1.6;
}

/* 关于我们 */
.about-section {
    padding: 80px 0;
    background: white;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
}

.about-text p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 2rem;
}

.features {
    display: flex;
    gap: 2rem;
    flex-wrap: wrap;
}

.feature {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-secondary);
}

.feature i {
    color: var(--primary-color);
    font-size: 1.2rem;
}

.stats-card {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 2rem;
    border-radius: var(--border-radius-lg);
    text-align: center;
}

.stats-card .stat {
    margin-bottom: 1.5rem;
}

.stats-card .stat:last-child {
    margin-bottom: 0;
}

.stats-card .stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stats-card .stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

/* 页脚 */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: white;
}

.footer-section h3 {
    font-size: 1.5rem;
    font-weight: 700;
}

.footer-section p {
    color: #9ca3af;
    line-height: 1.6;
    margin-bottom: 1rem;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #9ca3af;
    text-decoration: none;
    transition: var(--transition);
}

.footer-section ul li a:hover {
    color: white;
}

.footer-section ul li i {
    margin-right: 0.5rem;
    color: var(--primary-color);
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: var(--primary-color);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    transition: var(--transition);
}

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

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 2rem;
    text-align: center;
    color: #9ca3af;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .nav-toggle.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-stats {
        justify-content: center;
        flex-wrap: wrap;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .filter-tabs {
        justify-content: flex-start;
        overflow-x: auto;
        padding-bottom: 1rem;
    }

    .brands-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }

    .guide-steps {
        grid-template-columns: 1fr;
    }

    .features {
        flex-direction: column;
        gap: 1rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

    .coupon-card {
        padding: 1rem;
    }

    .discount-amount {
        font-size: 1.5rem;
    }

    .floating-card {
        padding: 1.5rem;
    }

    .floating-card i {
        font-size: 2rem;
    }
}

/* 动画效果 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.coupon-card,
.brand-item,
.step {
    animation: fadeInUp 0.6s ease-out;
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 4px;
}

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

/* 选择文本样式 */
::selection {
    background: var(--primary-color);
    color: white;
}

/* 焦点样式 */
button:focus,
a:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

/* 加载动画 */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}