:root {
    --primary-color: #1a237e;
    /* 深蓝 */
    --secondary-color: #ffc107;
    /* 暖黄 */
    --text-color: #333;
    --light-bg: #f5f5f5;
    --dark-bg: #121212;
    --dark-text: #e0e0e0;
}

body {
    font-family: 'Inter', sans-serif;
    color: var(--text-color);
    line-height: 1.6;
}

h1,
h2,
h3 {
    font-family: 'Playfair Display', serif;
}

.navbar {
    background-color: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.hero {
    background: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url('desk.jpg');
    background-size: cover;
    color: white;
}

.project-card {
    transition: transform 0.3s ease;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.project-card:hover {
    transform: translateY(-5px);
}

.polaroid {
    background: white;
    padding: 15px 15px 60px 15px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    transform: rotate(2deg);
    transition: transform 0.3s ease;
}

.polaroid:hover {
    transform: rotate(0deg) scale(1.05);
}

.btn {
    padding: 10px 20px;
    border-radius: 4px;
    transition: all 0.3s ease;
}

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

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

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

/* 夜间模式 */
.dark-mode {
    background-color: var(--dark-bg);
    color: var(--dark-text);
}

.dark-mode .navbar {
    background-color: var(--dark-bg);
}

.dark-mode .project-card,
.dark-mode .polaroid {
    background-color: #1e1e1e;
    color: var(--dark-text);
}

@media (max-width: 768px) {
    .navbar {
        flex-direction: column;
    }

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

    .about-content {
        flex-direction: column;
    }

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