* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Microsoft YaHei', 'Segoe UI', sans-serif;
}

body {
    background: linear-gradient(135deg, #6a11cb 0%, #2575fc 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 1200px;
    background-color: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
    padding: 40px;
    text-align: center;
    overflow: hidden;
    position: relative;
}

.container::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 70%);
    z-index: 0;
}

h1 {
    color: #2c3e50;
    font-size: 2.8rem;
    margin-bottom: 10px;
    position: relative;
    z-index: 1;
}

.subtitle {
    color: #7f8c8d;
    font-size: 1.2rem;
    margin-bottom: 40px;
    position: relative;
    z-index: 1;
}

.nav-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    position: relative;
    z-index: 1;
}

.nav-item {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    border-radius: 12px;
    padding: 25px 15px;
    text-align: center;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    cursor: pointer;
    transition: all 0.4s ease;
    position: relative;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.nav-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, rgba(106, 17, 203, 0.1) 0%, rgba(37, 117, 252, 0.1) 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.nav-item:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 25px rgba(0, 0, 0, 0.15);
}

.nav-item:hover::before {
    opacity: 1;
}

.nav-item .icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
    color: #6a11cb;
    transition: transform 0.4s ease;
}

.nav-item:hover .icon {
    transform: scale(1.2);
}

.nav-item h3 {
    color: #2c3e50;
    font-size: 1.3rem;
    margin-bottom: 10px;
}

.nav-item p {
    color: #7f8c8d;
    font-size: 0.9rem;
}

/* 点击动画 - 增强版 */
.nav-item.clicked {
    animation: clickEffect 0.6s ease;
}

@keyframes clickEffect {
    0% {
        transform: scale(1);
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
    }
    25% {
        transform: scale(0.95);
        box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
    }
    50% {
        transform: scale(1.05);
        box-shadow: 0 10px 20px rgba(106, 17, 203, 0.3);
        background: linear-gradient(135deg, #e0e7ff 0%, #a5b4fc 100%);
    }
    75% {
        transform: scale(0.98);
        box-shadow: 0 5px 15px rgba(37, 117, 252, 0.2);
    }
    100% {
        transform: scale(1);
        box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
        background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    }
}

/* 波纹效果 */
.ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.6);
    transform: scale(0);
    animation: ripple-animation 0.6s linear;
    pointer-events: none;
}

@keyframes ripple-animation {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

/* 响应式设计 */
@media (max-width: 768px) {
    .nav-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
    
    h1 {
        font-size: 2.2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 20px;
    }
    
    .nav-grid {
        grid-template-columns: 1fr;
    }
    
    h1 {
        font-size: 1.8rem;
    }
}