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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB',
        'Microsoft YaHei', 'Helvetica Neue', Helvetica, Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    padding: 20px;
    color: #333;
}

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

/* Header */
header {
    text-align: center;
    padding: 40px 20px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    margin-bottom: 40px;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
}

header h1 {
    font-size: 2.5rem;
    color: #667eea;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.2rem;
    color: #888;
    margin-bottom: 20px;
}

.clock {
    font-size: 1.5rem;
    color: #667eea;
    font-weight: 600;
    font-family: 'Courier New', monospace;
}

/* Grid */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

/* Cards */
.card {
    background: white;
    border-radius: 20px;
    padding: 40px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    position: relative;
    overflow: hidden;
}

.card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, #667eea, #764ba2);
}

.card:hover {
    box-shadow: 0 15px 50px rgba(0, 0, 0, 0.2);
}

.card-icon {
    font-size: 4rem;
    margin-bottom: 20px;
}

.card h2 {
    font-size: 1.8rem;
    margin-bottom: 15px;
    color: #333;
}

.card p {
    color: #666;
    line-height: 1.6;
    margin-bottom: 25px;
}

.card-footer {
    display: flex;
    gap: 10px;
    flex-wrap: wrap;
}

.tag {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

/* Footer */
footer {
    text-align: center;
    padding: 30px;
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

footer p {
    color: #666;
    margin-bottom: 10px;
    font-size: 0.95rem;
}

.update-time {
    font-size: 0.85rem;
    color: #999;
}

/* Responsive */
@media (max-width: 768px) {
    header h1 {
        font-size: 2rem;
    }

    .clock {
        font-size: 1.2rem;
    }

    .card {
        padding: 30px;
    }

    .card-icon {
        font-size: 3rem;
    }

    .card h2 {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    header {
        padding: 30px 15px;
    }

    header h1 {
        font-size: 1.8rem;
    }

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

    .card {
        padding: 25px;
    }
}

/* Animation */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.card {
    animation: fadeIn 0.5s ease-out;
}

.card:nth-child(2) {
    animation-delay: 0.1s;
}

.card:nth-child(3) {
    animation-delay: 0.2s;
}