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

body {
    font-family: 'PingFang SC', '思源黑体', 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

/* 头部样式 */
.header {
    text-align: center;
    padding: 3rem 2rem 2rem;
    color: white;
}

.title {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.subtitle {
    font-size: 1.2rem;
    opacity: 0.9;
    font-weight: 300;
}

/* 主内容区域 */
.main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem 4rem;
}

/* 分类网格布局 */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

/* 分类卡片样式 */
.category-card {
    background: white;
    border-radius: 16px;
    padding: 2rem;
    box-shadow: 0 8px 32px rgba(0,0,0,0.1);
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

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

.category-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 16px 48px rgba(0,0,0,0.15);
}

/* 分类图标 */
.category-icon {
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 80px;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    border-radius: 12px;
    margin: -1rem -1rem 1rem -1rem;
}

.icon-svg {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

/* 分类标题 */
.category-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #2c3e50;
}

/* 分类描述 */
.category-desc {
    color: #666;
    margin-bottom: 1rem;
    line-height: 1.5;
}

/* 项目数量 */
.project-count {
    background: linear-gradient(135deg, #667eea, #764ba2);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 20px;
    font-size: 0.9rem;
    font-weight: 500;
    display: inline-block;
    margin-top: auto;
}

/* 页脚 */
.footer {
    text-align: center;
    padding: 2rem;
    color: white;
    opacity: 0.8;
}

/* 授权弹窗样式 */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.35);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal {
    width: 92%;
    max-width: 420px;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0,0,0,0.25);
    padding: 1.5rem;
}

.modal-title {
    margin-bottom: 0.5rem;
    font-size: 1.25rem;
    color: #2c3e50;
}

.modal-desc {
    color: #666;
    margin-bottom: 1rem;
}

.modal-input {
    width: 100%;
    padding: 0.7rem 0.9rem;
    border: 1px solid #e5e7eb;
    border-radius: 10px;
    outline: none;
    font-size: 1rem;
}

.modal-error {
    color: #e11d48;
    font-size: 0.9rem;
    margin-top: 0.5rem;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
    margin-top: 1.25rem;
}

.btn {
    padding: 0.55rem 1rem;
    border-radius: 10px;
    border: none;
    cursor: pointer;
}

.btn-secondary { background: #f3f4f6; color: #111827; }
.btn-primary { background: linear-gradient(135deg, #667eea, #764ba2); color: #fff; }

/* 响应式设计 */
@media (max-width: 768px) {
    .title {
        font-size: 2rem;
    }
    
    .subtitle {
        font-size: 1rem;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .category-card {
        padding: 1.5rem;
    }
    
    .main {
        padding: 0 1rem 2rem;
    }
}

@media (max-width: 480px) {
    .header {
        padding: 2rem 1rem 1rem;
    }
    
    .title {
        font-size: 1.8rem;
    }
    
    .category-card {
        padding: 1rem;
    }
}