/* 全局样式 */
:root {
    --primary-color: #4A90E2;
    --primary-color-dark: #357ABD;
    --secondary-color: #2C3E50;
    --text-color: #333;
    --text-light: #666;
    --background-light: #F8F9FA;
    --white: #FFFFFF;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-hover: 0 4px 8px rgba(0,0,0,0.2);
    --transition: all 0.3s ease;
}

/* Hero section 样式 */
.hero {
    background: linear-gradient(135deg, #4A90E2 0%, #357ABD 100%);
    padding: 60px 0 80px;
    color: var(--white);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at center, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0) 70%);
}

.hero .container {
    position: relative;
    z-index: 1;
}

.hero h1 {
    font-size: 3.5em;
    margin: 40px 0 20px;
    font-weight: 700;
    text-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.hero p {
    font-size: 1.3em;
    margin-bottom: 40px;
    opacity: 0.9;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

/* 分类导航样式 */
.category-nav {
    background-color: var(--white);
    padding: 40px 0;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    margin-bottom: 0;
}

.category-buttons {
    display: flex;
    justify-content: space-between;
    gap: 20px;
    flex-wrap: wrap;
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

.category-btn {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 30px 20px;
    background-color: var(--background-light);
    border: 2px solid rgba(74, 144, 226, 0.2);
    border-radius: 16px;
    text-decoration: none;
    color: var(--text-color);
    transition: var(--transition);
    min-width: 220px;
    box-shadow: var(--shadow);
    position: relative;
    overflow: hidden;
}

.category-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--primary-color);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.category-btn:hover::before {
    transform: scaleX(1);
}

.category-btn:hover {
    transform: translateY(-5px);
    background-color: var(--white);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-hover);
}

.category-btn i {
    font-size: 38px;
    margin-bottom: 20px;
    color: var(--primary-color);
    transition: var(--transition);
}

.category-btn:hover i {
    transform: scale(1.2);
}

.category-btn span {
    font-weight: 600;
    font-size: 1.25em;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    text-align: center;
    line-height: 1.4;
}

/* 热门工具样式 */
.popular-tools {
    padding: 80px 0;
    background-color: var(--white);
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.title-wrapper {
    display: inline-block;
    position: relative;
}

.section-header h2 {
    color: var(--text-color);
    font-size: 2.8em;
    font-weight: 700;
    margin-bottom: 20px;
    text-align: center;
}

.title-decoration {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
    margin-top: 15px;
}

.title-decoration .line {
    width: 60px;
    height: 3px;
    background: var(--primary-color);
    position: relative;
}

.title-decoration .line::before {
    content: '';
    position: absolute;
    width: 6px;
    height: 6px;
    background: var(--primary-color);
    border-radius: 50%;
    top: 50%;
    transform: translateY(-50%);
}

.title-decoration .line:first-child::before {
    right: 0;
}

.title-decoration .line:last-child::before {
    left: 0;
}

.title-decoration i {
    color: var(--primary-color);
    font-size: 1.2em;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.tool-card {
    background: var(--white);
    border-radius: 15px;
    padding: 25px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid rgba(0,0,0,0.05);
}

.tool-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.tool-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.tool-header h3 {
    margin: 0;
}

.tool-header h3 a {
    color: var(--text-color);
    text-decoration: none;
    transition: var(--transition);
    font-size: 1.2em;
}

.tool-header h3 a:hover {
    color: var(--primary-color);
}

.category-tag {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 0.85em;
    font-weight: 500;
}

.tool-card p {
    color: var(--text-light);
    margin-bottom: 25px;
    line-height: 1.6;
    font-size: 1em;
}

.tool-footer {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: auto;
    padding-top: 15px;
    border-top: 1px solid rgba(0,0,0,0.05);
}

.rating {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #FFB800;
}

.rating i {
    font-size: 1.1em;
}

.rating span {
    color: var(--text-light);
    font-weight: 500;
}

.btn-primary {
    background-color: var(--primary-color);
    color: var(--white);
    padding: 10px 20px;
    border-radius: 25px;
    text-decoration: none;
    transition: var(--transition);
    font-weight: 500;
    font-size: 0.95em;
}

.btn-primary:hover {
    background-color: var(--primary-color-dark);
    transform: translateY(-2px);
}

/* 响应式设计 */
@media (max-width: 1200px) {
    .category-buttons {
        justify-content: center;
        max-width: 1000px;
    }
    
    .category-btn {
        min-width: 200px;
        flex: 0 1 calc(33.333% - 20px);
    }
}

@media (max-width: 768px) {
    .category-nav {
        padding: 30px 0;
    }

    .category-buttons {
        gap: 15px;
    }

    .category-btn {
        min-width: calc(50% - 15px);
        flex: 0 1 calc(50% - 15px);
        padding: 25px 15px;
    }

    .category-btn i {
        font-size: 32px;
        margin-bottom: 15px;
    }

    .category-btn span {
        font-size: 1.1em;
    }
}

@media (max-width: 480px) {
    .category-btn {
        min-width: 100%;
        flex: 0 1 100%;
    }
}