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

body {
    font-family: 'Noto Sans SC', 'Montserrat', sans-serif;
    line-height: 1.6;
    color: #333;
    overflow-x: hidden;
}

/* 自定义属性 - 色彩系统 */
:root {
    --primary-color: #2A5DB0;      /* 主色（专业） */
    --secondary-color: #FF6B35;    /* 辅助色（活力） */
    --background-color: #FFFFFF;    /* 背景色 */
    --text-primary: #1f2937;       /* 主要文字 */
    --text-secondary: #6b7280;     /* 次要文字 */
    --border-color: #e5e7eb;       /* 边框色 */
    --shadow-light: rgba(0, 0, 0, 0.1);
    --shadow-medium: rgba(0, 0, 0, 0.15);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 1rem 0;
    transition: all 0.3s ease;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-logo h2 {
    color: var(--primary-color);
    font-size: 1.8rem;
    font-weight: 700;
    font-family: 'Montserrat', sans-serif;
}

.nav-logo span {
    color: #64748b;
    font-size: 0.9rem;
    font-weight: 400;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #374151;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: var(--primary-color);
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
}

.bar {
    width: 25px;
    height: 3px;
    background: #374151;
    margin: 3px 0;
    transition: 0.3s;
}

/* 主页横幅 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding-top: 80px;
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    padding: 12px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

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

.btn-primary:hover {
    background: #1e4a8a;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(42, 93, 176, 0.3);
}

.btn-secondary {
    background: var(--secondary-color);
    color: white;
    border: 2px solid var(--secondary-color);
}

.btn-secondary:hover {
    background: #e55a2b;
    border-color: #e55a2b;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(255, 107, 53, 0.3);
}

.btn-secondary {
    background: transparent;
    color: white;
    border: 2px solid white;
}

.btn-secondary:hover {
    background: white;
    color: #2563eb;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

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

.hero-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
    margin-top: 2rem;
}

.stat-item {
    text-align: center;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 15px;
    backdrop-filter: blur(10px);
}

.stat-item h3 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-item p {
    font-size: 1rem;
    opacity: 0.8;
}

/* 章节标题 */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-header h2 {
    font-size: 2.5rem;
    font-weight: 700;
    color: #1f2937;
    margin-bottom: 1rem;
}

.section-header p {
    font-size: 1.1rem;
    color: #6b7280;
}

/* 关于我们 */
.about {
    padding: 6rem 0;
    background: #f8fafc;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-text h3 {
    font-size: 2rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1.5rem;
}

.about-text p {
    font-size: 1.1rem;
    color: #6b7280;
    margin-bottom: 2rem;
    line-height: 1.8;
}

.features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.feature {
    text-align: center;
    padding: 1.5rem;
    background: white;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s ease;
}

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

.feature i {
    font-size: 2rem;
    color: #2563eb;
    margin-bottom: 1rem;
}

.feature h4 {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #1f2937;
}

.feature p {
    font-size: 0.9rem;
    color: #6b7280;
}

.about-image img {
    width: 100%;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

/* 培训课程 */
.services {
    padding: 6rem 0;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2.5rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, #2563eb, #7c3aed);
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.service-card.featured {
    border: 2px solid #2563eb;
    transform: scale(1.05);
}

.service-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, #2563eb, #7c3aed);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.service-icon i {
    font-size: 2rem;
    color: white;
}

.service-card h3 {
    font-size: 1.5rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
}

.service-card p {
    color: #6b7280;
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.service-features {
    list-style: none;
    margin-bottom: 2rem;
}

.service-features li {
    padding: 0.5rem 0;
    color: #374151;
    position: relative;
    padding-left: 1.5rem;
}

.service-features li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: #2563eb;
    font-weight: bold;
}

/* 师资团队 */
.teachers {
    padding: 6rem 0;
    background: #f8fafc;
}

.teachers-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.teacher-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

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

.teacher-image {
    height: 250px;
    overflow: hidden;
    background: linear-gradient(135deg, #667eea, #764ba2);
    display: flex;
    align-items: center;
    justify-content: center;
}

.teacher-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.teacher-info {
    padding: 2rem;
}

.teacher-info h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.teacher-title {
    color: #2563eb;
    font-weight: 500;
    margin-bottom: 1rem;
}

.teacher-desc {
    color: #6b7280;
    line-height: 1.6;
}

/* 经验技巧 */
.tips {
    padding: 6rem 0;
    background: #f8fafc;
}

.tips-filter {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.filter-btn {
    padding: 10px 20px;
    border: 2px solid #e5e7eb;
    background: white;
    color: #374151;
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.filter-btn:hover,
.filter-btn.active {
    background: #2563eb;
    color: white;
    border-color: #2563eb;
    transform: translateY(-2px);
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.tip-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    opacity: 1;
    transform: translateY(0);
}

.tip-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.tip-card.hidden {
    display: none;
}

.tip-card.fade-out {
    opacity: 0;
    transform: translateY(20px);
}

.tip-image {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.tip-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.tip-card:hover .tip-image img {
    transform: scale(1.1);
}

.tip-category {
    position: absolute;
    top: 15px;
    left: 15px;
    background: rgba(37, 99, 235, 0.9);
    color: white;
    padding: 5px 12px;
    border-radius: 15px;
    font-size: 0.8rem;
    font-weight: 500;
}

.tip-content {
    padding: 1.5rem;
}

.tip-content h3 {
    font-size: 1.3rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 1rem;
    line-height: 1.4;
}

.tip-content p {
    color: #6b7280;
    line-height: 1.6;
    margin-bottom: 1.5rem;
}

.tip-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    color: #9ca3af;
}

.tip-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.tip-meta i {
    font-size: 0.8rem;
}

.read-more {
    width: 100%;
    text-align: center;
    padding: 10px 20px;
    font-size: 0.9rem;
}

.load-more {
    text-align: center;
}

.load-more .btn {
    padding: 15px 40px;
    font-size: 1.1rem;
}

/* 在线测试系统 */
.test-system {
    padding: 6rem 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, #1e4a8a 100%);
    color: white;
}

.test-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.test-info {
    display: grid;
    gap: 2rem;
}

.test-feature {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 10px;
    backdrop-filter: blur(10px);
}

.test-feature i {
    font-size: 2rem;
    color: var(--secondary-color);
    margin-top: 0.2rem;
}

.test-feature h4 {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.test-feature p {
    opacity: 0.9;
    line-height: 1.6;
}

.test-form {
    background: white;
    padding: 2.5rem;
    border-radius: 15px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.test-form h3 {
    color: var(--text-primary);
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 2rem;
    text-align: center;
}

/* 学员成果展示 */
.results {
    padding: 6rem 0;
    background: #f8fafc;
}

.results-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 3rem;
    flex-wrap: wrap;
}

.tab-btn {
    padding: 12px 24px;
    border: 2px solid var(--border-color);
    background: white;
    color: var(--text-secondary);
    border-radius: 25px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 500;
}

.tab-btn:hover,
.tab-btn.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
    transform: translateY(-2px);
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* 成功案例 */
.stories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
}

.story-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px var(--shadow-light);
    transition: all 0.3s ease;
}

.story-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px var(--shadow-medium);
}

.story-image {
    height: 200px;
    overflow: hidden;
}

.story-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.story-content {
    padding: 1.5rem;
}

.story-content h4 {
    font-size: 1.2rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.story-desc {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 1.5rem;
    font-style: italic;
}

.story-stats {
    display: flex;
    gap: 1rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.story-stats span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* 学员视频 */
.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.video-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 10px 30px var(--shadow-light);
    transition: all 0.3s ease;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px var(--shadow-medium);
}

.video-thumbnail {
    position: relative;
    height: 200px;
    overflow: hidden;
}

.video-thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.play-btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.play-btn i {
    font-size: 1.5rem;
    color: var(--primary-color);
}

.play-btn:hover {
    background: var(--primary-color);
    transform: translate(-50%, -50%) scale(1.1);
}

.play-btn:hover i {
    color: white;
}

.video-card h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 1rem;
    margin-bottom: 0.5rem;
}

.video-card p {
    color: var(--text-secondary);
    margin: 0 1rem 1rem;
    line-height: 1.6;
}

/* 数据统计 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.stat-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 30px var(--shadow-light);
    transition: all 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 20px 40px var(--shadow-medium);
}

.stat-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 1.5rem;
}

.stat-icon i {
    font-size: 2rem;
    color: white;
}

.stat-card h3 {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-card p {
    font-size: 1.1rem;
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
}

.stat-detail {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.stat-detail span {
    padding: 0.5rem;
    background: #f8fafc;
    border-radius: 5px;
}

/* 联系我们 */
.contact {
    padding: 6rem 0;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
}

.contact-info {
    display: grid;
    gap: 2rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: #f8fafc;
    border-radius: 10px;
    transition: transform 0.3s ease;
}

.contact-item:hover {
    transform: translateX(5px);
}

.contact-item i {
    font-size: 1.5rem;
    color: #2563eb;
    margin-top: 0.2rem;
}

.contact-item h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: #1f2937;
    margin-bottom: 0.5rem;
}

.contact-item p {
    color: #6b7280;
}

.contact-form {
    background: white;
    padding: 2.5rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e5e7eb;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
    font-family: inherit;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: #2563eb;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* 页脚 */
.footer {
    background: #1f2937;
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: white;
}

.footer-section p {
    color: #d1d5db;
    line-height: 1.6;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section ul li a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #2563eb;
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-links a {
    width: 40px;
    height: 40px;
    background: #374151;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    text-decoration: none;
    transition: all 0.3s ease;
}

.social-links a:hover {
    background: #2563eb;
    transform: translateY(-2px);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #374151;
    color: #9ca3af;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background-color: white;
        width: 100%;
        text-align: center;
        transition: 0.3s;
        box-shadow: 0 10px 27px rgba(0, 0, 0, 0.05);
        padding: 2rem 0;
    }

    .nav-menu.active {
        left: 0;
    }

    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2rem;
    }

    .hero-content h1 {
        font-size: 2.5rem;
    }

    .hero-buttons {
        justify-content: center;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

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

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

    .tips-filter {
        gap: 0.5rem;
    }

    .filter-btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }

    .test-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .results-tabs {
        gap: 0.5rem;
    }

    .tab-btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }

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

    .section-header h2 {
        font-size: 2rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .hero-content h1 {
        font-size: 2rem;
    }

    .btn {
        padding: 10px 20px;
        font-size: 0.9rem;
    }

    .service-card {
        padding: 1.5rem;
    }

    .contact-form {
        padding: 1.5rem;
    }
}

/* 动画效果 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

/* 滚动条样式 */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
}

::-webkit-scrollbar-thumb {
    background: #2563eb;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #1d4ed8;
}

/* 文章详情模态框 */
.article-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 10000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(5px);
}

.modal-content {
    position: relative;
    background: white;
    border-radius: 15px;
    max-width: 800px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    animation: modalSlideIn 0.3s ease-out;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-50px) scale(0.9);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.modal-header {
    padding: 2rem 2rem 1rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
}

.modal-header h2 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-primary);
    margin: 0;
    line-height: 1.3;
}

.modal-close {
    background: none;
    border: none;
    font-size: 2rem;
    color: var(--text-secondary);
    cursor: pointer;
    padding: 0;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.3s ease;
}

.modal-close:hover {
    background: var(--border-color);
    color: var(--text-primary);
}

.modal-body {
    padding: 1rem 2rem 2rem;
}

.article-meta {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 1rem;
    background: #f8fafc;
    border-radius: 10px;
    flex-wrap: wrap;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.article-meta span {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.article-content {
    line-height: 1.8;
    color: var(--text-primary);
}

.article-content h2 {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--primary-color);
    margin: 2rem 0 1rem;
    border-left: 4px solid var(--primary-color);
    padding-left: 1rem;
}

.article-content h2:first-child {
    margin-top: 0;
}

.article-content p {
    margin-bottom: 1rem;
    color: var(--text-primary);
}

.article-content ul {
    margin: 1rem 0;
    padding-left: 2rem;
}

.article-content li {
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* 响应式模态框 */
@media (max-width: 768px) {
    .modal-content {
        width: 95%;
        max-height: 95vh;
    }
    
    .modal-header {
        padding: 1.5rem 1.5rem 1rem;
    }
    
    .modal-header h2 {
        font-size: 1.3rem;
    }
    
    .modal-body {
        padding: 1rem 1.5rem 1.5rem;
    }
    
    .article-meta {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* 加载动画 */
.loading-spinner {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.loading-spinner i {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.loading-spinner p {
    margin: 0;
    font-size: 1rem;
}

/* 错误状态 */
.error-message {
    text-align: center;
    padding: 3rem;
    color: var(--text-secondary);
}

.error-message i {
    font-size: 3rem;
    color: #ef4444;
    margin-bottom: 1rem;
}

.error-message h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
}

.error-message p {
    margin: 0;
} 

/* 在线测试系统样式 */
.test-quiz-box {
    max-width: 500px;
    margin: 2rem auto 0 auto;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(42,93,176,0.08);
    padding: 2rem 2rem 1.5rem 2rem;
    position: relative;
    z-index: 2;
}
.test-quiz-panel h3 {
    font-size: 1.1rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}
.test-question {
    font-size: 1.1rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}
.test-options label {
    display: block;
    background: #f3f6fa;
    border-radius: 8px;
    padding: 0.75rem 1rem;
    margin-bottom: 1rem;
    cursor: pointer;
    transition: background 0.2s;
    font-size: 1rem;
}
.test-options input[type="radio"] {
    margin-right: 0.75rem;
}
.test-options label:hover {
    background: #e6f0ff;
}
.test-quiz-actions {
    text-align: right;
    margin-top: 1.5rem;
}
.test-result-panel {
    text-align: center;
    padding: 2rem 1rem;
}
.test-score {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}
.test-level {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}
.test-level-badge {
    display: inline-block;
    background: #e0e7ff;
    color: #2a5db0;
    border-radius: 6px;
    padding: 0.2em 0.8em;
    font-weight: 600;
    margin-left: 0.5em;
}
.test-recommend {
    font-size: 1.1rem;
    margin-bottom: 1rem;
}
.test-recommend-badge {
    display: inline-block;
    background: #fff7ed;
    color: #ff6b35;
    border-radius: 6px;
    padding: 0.2em 0.8em;
    font-weight: 600;
    margin-left: 0.5em;
}
.test-result-text {
    margin: 1.5rem 0 0.5rem 0;
    color: var(--text-secondary);
    font-size: 1rem;
}
@media (max-width: 600px) {
    .test-quiz-box {
        padding: 1rem 0.5rem 1rem 0.5rem;
    }
    .test-quiz-panel h3 {
        font-size: 1rem;
    }
}