/* Website 157 - 纸张折叠风格 (Paper Fold)
 * 布局：纸张折叠效果，卡片层次感
 * 主题色：暖灰色 (#78716c) + 棕色 (#a16207)
 */

:root {
    --primary-color: #a16207;
    --primary-dark: #854d0e;
    --primary-light: #fbbf24;
    --accent-color: #78716c;
    --accent-light: #a8a29e;
    --bg-dark: #1c1917;
    --bg-card: #292524;
    --text-primary: #fef3c7;
    --text-secondary: #fed7aa;
    --border-color: #92400e;
    --shadow-color: rgba(161, 98, 7, 0.4);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: linear-gradient(135deg, var(--bg-dark) 0%, #1f1b18 50%, var(--bg-dark) 100%);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
}

.paper-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(28, 25, 23, 0.95);
    backdrop-filter: blur(10px);
    padding: 0 40px;
    height: 70px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    z-index: 1000;
    border-bottom: 2px solid var(--primary-color);
}

.nav-logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-light);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-links {
    display: flex;
    gap: 8px;
    list-style: none;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
    padding: 10px 18px;
    border-radius: 4px;
    transition: all 0.3s ease;
    font-weight: 500;
    font-size: 0.95rem;
    border: 1px solid transparent;
}

.nav-links a:hover,
.nav-links a.active {
    background: var(--bg-card);
    border-color: var(--primary-color);
    box-shadow: 3px 3px 0 var(--primary-color);
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.menu-toggle span {
    width: 25px;
    height: 2px;
    background: var(--primary-light);
    transition: all 0.3s ease;
}

.main-content {
    padding-top: 70px;
}

.paper-hero {
    padding: 80px 40px;
    text-align: center;
    background: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 10px,
        rgba(161, 98, 7, 0.03) 10px,
        rgba(161, 98, 7, 0.03) 20px
    );
}

.paper-hero-content {
    max-width: 900px;
    margin: 0 auto;
}

.paper-hero h1 {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 20px;
    color: var(--primary-light);
}

.paper-hero p {
    font-size: 1.25rem;
    color: var(--text-secondary);
    margin-bottom: 30px;
}

.paper-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 24px;
    padding: 40px;
    max-width: 1600px;
    margin: 0 auto;
}

.paper-card {
    background: var(--bg-card);
    border-radius: 4px;
    padding: 30px;
    position: relative;
    overflow: hidden;
    transition: all 0.4s ease;
    border: 1px solid var(--border-color);
    box-shadow: 5px 5px 0 var(--border-color);
}

.paper-card:hover {
    transform: translateY(-8px);
    box-shadow: 8px 8px 0 var(--primary-color);
}

.paper-card .card-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    font-size: 1.8rem;
}

.paper-card h3 {
    font-size: 1.35rem;
    margin-bottom: 12px;
    color: var(--primary-light);
}

.paper-card p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.paper-card .card-tag {
    position: absolute;
    top: 20px;
    right: 20px;
    background: var(--primary-color);
    color: white;
    padding: 4px 12px;
    border-radius: 2px;
    font-size: 0.75rem;
    font-weight: 600;
}

.paper-section {
    padding: 80px 40px;
    background: rgba(161, 98, 7, 0.1);
}

.section-title {
    text-align: center;
    font-size: 2.2rem;
    margin-bottom: 50px;
    color: var(--primary-light);
}

.paper-grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    max-width: 1400px;
    margin: 0 auto;
}

.paper-item {
    background: var(--bg-card);
    border-radius: 4px;
    padding: 35px;
    text-align: center;
    border: 1px solid var(--border-color);
    box-shadow: 5px 5px 0 var(--border-color);
    transition: all 0.3s ease;
}

.paper-item:hover {
    transform: translateY(-5px);
    box-shadow: 8px 8px 0 var(--primary-color);
}

.paper-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
}

.paper-item h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--primary-light);
}

.paper-item p {
    color: var(--text-secondary);
    font-size: 0.95rem;
}

.paper-contact {
    padding: 80px 40px;
    background: linear-gradient(135deg, var(--bg-card) 0%, var(--bg-dark) 100%);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.paper-contact-card {
    background: var(--bg-card);
    padding: 35px;
    border-radius: 4px;
    text-align: center;
    border: 1px solid var(--border-color);
    box-shadow: 5px 5px 0 var(--border-color);
    transition: all 0.3s ease;
}

.paper-contact-card:hover {
    transform: translateY(-5px);
    box-shadow: 8px 8px 0 var(--primary-color);
}

.paper-contact-icon {
    width: 70px;
    height: 70px;
    margin: 0 auto 20px;
    background: linear-gradient(135deg, var(--primary-color), var(--accent-color));
    border-radius: 2px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.8rem;
}

.paper-contact-card h4 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--primary-light);
}

.paper-contact-card p {
    color: var(--text-secondary);
    font-size: 1rem;
}

.paper-footer {
    background: var(--bg-dark);
    padding: 40px;
    text-align: center;
    border-top: 2px solid var(--border-color);
}

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

@media (max-width: 768px) {
    .paper-nav {
        padding: 0 20px;
    }

    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: rgba(28, 25, 23, 0.98);
        flex-direction: column;
        padding: 20px;
        gap: 10px;
        transform: translateY(-150%);
    }

    .nav-links.active {
        transform: translateY(0);
    }

    .menu-toggle {
        display: flex;
    }

    .paper-hero {
        padding: 60px 20px;
    }

    .paper-hero h1 {
        font-size: 2rem;
    }

    .paper-grid {
        padding: 20px;
        grid-template-columns: 1fr;
    }

    .paper-section,
    .paper-contact {
        padding: 60px 20px;
    }

    .section-title {
        font-size: 1.8rem;
    }
}