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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f9f9f9;
}

a {
    text-decoration: none;
    color: inherit;
}

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

/* ============ 按钮样式 ============ */
.btn-primary {
    background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
    display: inline-block;
    text-decoration: none;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #1e40af 0%, #2563eb 100%);
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(30, 58, 138, 0.3);
}

.btn-header {
    padding: 10px 20px;
    font-size: 13px;
}

.btn-large {
    padding: 16px 40px;
    font-size: 16px;
}

/* ============ Header 导航栏 ============ */
.header {
    background: white;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
}

.logo {
    font-size: 20px;
    font-weight: 700;
    color: #1e3a8a;
    white-space: nowrap;
}

.nav {
    display: flex;
    gap: 30px;
    flex: 1;
    margin-left: 60px;
}

.nav a {
    color: #666;
    font-size: 14px;
    transition: color 0.3s;
}

.nav a:hover {
    color: #1e3a8a;
}

/* ============ Hero 部分 ============ */
.hero {
    background: linear-gradient(135deg, #f3f4f6 0%, #e5e7eb 100%);
    padding: 80px 0;
    text-align: center;
}

.hero .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 60px;
}

.hero-content {
    flex: 1;
    text-align: left;
}

.hero h1 {
    font-size: 42px;
    line-height: 1.2;
    margin-bottom: 20px;
    color: #1e3a8a;
}

.hero p {
    font-size: 18px;
    color: #666;
    margin-bottom: 30px;
}

.hero-stats {
    display: flex;
    gap: 40px;
    justify-content: flex-start;
    margin-top: 50px;
}

.stat {
    text-align: center;
}

.stat-number {
    font-size: 32px;
    font-weight: 700;
    color: #1e3a8a;
}

.stat-text {
    font-size: 14px;
    color: #666;
    margin-top: 5px;
}

/* ============ 优势对比 部分 ============ */
.advantages {
    padding: 80px 0;
    background: white;
}

.advantages h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 50px;
    color: #1e3a8a;
}

.comparison-table {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
}

.comparison-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    padding: 50px 60px;
}

.comparison-col h4 {
    font-size: 22px;
    margin-bottom: 25px;
    text-align: center;
    font-weight: 700;
}

.comparison-col:first-child h4 {
    color: #dc2626;
}

.comparison-col:last-child h4 {
    color: #16a34a;
}

.comparison-list {
    list-style: none;
}

.comparison-list li {
    padding: 14px 0;
    font-size: 15px;
    line-height: 1.6;
    border-bottom: 1px solid #e5e7eb;
    text-align: left;
}

.comparison-list li:last-child {
    border-bottom: none;
}

.comparison-list.bad li {
    color: #666;
}

.comparison-list.good li {
    color: #16a34a;
    font-weight: 500;
}

/* ============ 理论基础 部分 ============ */
.theory {
    padding: 80px 0;
    background: #f9fafb;
}

.theory h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 15px;
    color: #1e3a8a;
}

.section-intro {
    text-align: center;
    color: #666;
    margin-bottom: 50px;
    font-size: 16px;
}

.types-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.type-card {
    background: white;
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border-top: 4px solid #1e3a8a;
}

.type-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.12);
}

.type-icon {
    width: 60px;
    height: 60px;
    background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 100%);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    margin: 0 auto 20px;
}

.type-card h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #1e3a8a;
}

.type-card p {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
}

.type-examples {
    font-size: 13px;
    color: #999;
    padding-top: 12px;
    border-top: 1px solid #e5e7eb;
    margin-top: 12px;
}

/* ============ 测评流程 部分 ============ */
.process {
    padding: 80px 0;
    background: white;
}

.process h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 60px;
    color: #1e3a8a;
}

.steps-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 20px;
    flex-wrap: wrap;
}

.step {
    flex: 1;
    min-width: 280px;
    background: linear-gradient(135deg, #f3f4f6 0%, #e5e7eb 100%);
    border-radius: 12px;
    padding: 40px 30px;
    text-align: center;
}

.step-number {
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 100%);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    font-weight: 700;
    margin: 0 auto 20px;
}

.step h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #1e3a8a;
}

.step p {
    color: #666;
    margin-bottom: 15px;
    line-height: 1.6;
}

.step-detail {
    font-size: 12px;
    color: #999;
    padding-top: 12px;
    border-top: 1px solid #d1d5db;
}

.step-arrow {
    font-size: 24px;
    color: #1e3a8a;
    flex-shrink: 0;
}

/* ============ 报告内容 部分 ============ */
.report-preview {
    padding: 80px 0;
    background: #f9fafb;
}

.report-preview h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 50px;
    color: #1e3a8a;
}

.report-items {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
}

.report-item {
    background: white;
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.report-icon {
    font-size: 40px;
    margin-bottom: 15px;
}

.report-item h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #1e3a8a;
}

.report-item p {
    color: #666;
    line-height: 1.6;
}

/* ============ 应用场景 部分 ============ */
.applications {
    padding: 80px 0;
    background: white;
}

.applications h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 50px;
    color: #1e3a8a;
}

.app-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.app-card {
    background: linear-gradient(135deg, #f3f4f6 0%, #e5e7eb 100%);
    border-radius: 12px;
    padding: 30px;
    border-left: 4px solid #1e3a8a;
    transition: all 0.3s ease;
}

.app-card:hover {
    transform: translateX(8px);
}

.app-card h3 {
    font-size: 18px;
    margin-bottom: 12px;
    color: #1e3a8a;
}

.app-card p {
    color: #666;
    line-height: 1.6;
}

/* ============ 数据支撑 部分 ============ */
.data-support {
    padding: 80px 0;
    background: linear-gradient(135deg, #1e3a8a 0%, #1e40af 100%);
    color: white;
    text-align: center;
}

.data-support h2 {
    font-size: 36px;
    margin-bottom: 50px;
    color: white;
}

.data-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.data-card {
    background: rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 40px 20px;
    backdrop-filter: blur(10px);
}

.data-number {
    font-size: 42px;
    font-weight: 700;
    margin-bottom: 10px;
}

.data-desc {
    font-size: 16px;
    opacity: 0.9;
}

/* ============ FAQ 部分 ============ */
.faq {
    padding: 80px 0;
    background: white;
}

.faq h2 {
    font-size: 36px;
    text-align: center;
    margin-bottom: 50px;
    color: #1e3a8a;
}

.faq-items {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    border-bottom: 1px solid #e5e7eb;
    padding: 20px 0;
    cursor: pointer;
    transition: all 0.3s ease;
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-question {
    font-size: 16px;
    font-weight: 600;
    color: #1e3a8a;
    margin-bottom: 12px;
}

.faq-answer {
    font-size: 14px;
    color: #666;
    line-height: 1.6;
    display: block;
}

/* ============ CTA 部分 ============ */
.cta-section {
    padding: 80px 0;
    background: linear-gradient(135deg, #f3f4f6 0%, #e5e7eb 100%);
    text-align: center;
}

.cta-section h2 {
    font-size: 36px;
    margin-bottom: 15px;
    color: #1e3a8a;
}

.cta-section p {
    font-size: 18px;
    color: #666;
    margin-bottom: 30px;
}

/* ============ Footer ============ */
.footer {
    background: #1f2937;
    color: #e5e7eb;
    padding: 50px 0 20px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 40px;
    margin-bottom: 30px;
}

.footer-left h3 {
    color: white;
    margin-bottom: 8px;
    font-size: 18px;
}

.footer-left p {
    font-size: 14px;
    color: #9ca3af;
}

.footer-links {
    display: flex;
    gap: 30px;
}

.footer-links a {
    color: #d1d5db;
    font-size: 14px;
    transition: color 0.3s;
}

.footer-links a:hover {
    color: #1e3a8a;
}

.footer-bottom {
    text-align: center;
    padding-top: 15px;
    border-top: 1px solid #374151;
    font-size: 12px;
    color: #9ca3af;
}

@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
        text-align: center;
    }

    .footer-links {
        flex-wrap: wrap;
        justify-content: center;
    }
}

/* ============ 响应式设计 ============ */
@media (max-width: 768px) {
    body {
        font-size: 15px;
    }

    .container {
        padding: 0 16px;
    }

    .header .container {
        flex-wrap: wrap;
        gap: 12px;
        padding: 12px 16px;
    }

    .logo {
        font-size: 16px;
        flex: 1;
    }

    .nav {
        order: 3;
        width: 100%;
        margin-left: 0;
        gap: 12px;
        flex-wrap: wrap;
    }

    .nav a {
        font-size: 13px;
    }

    .btn-header {
        order: 2;
        padding: 9px 16px;
        font-size: 12px;
        white-space: nowrap;
    }

    .btn-primary {
        padding: 11px 20px;
        font-size: 13px;
    }

    .btn-large {
        padding: 13px 32px;
        font-size: 14px;
        width: 100%;
        max-width: 300px;
    }

    .hero {
        padding: 60px 0 40px;
    }

    .hero .container {
        flex-direction: column;
        gap: 30px;
    }

    .hero-content {
        text-align: center;
    }

    .hero h1 {
        font-size: 28px;
        line-height: 1.3;
        margin-bottom: 16px;
    }

    .hero p {
        font-size: 14px;
        margin-bottom: 24px;
        line-height: 1.6;
    }

    .hero-stats {
        justify-content: center;
        gap: 15px;
        flex-direction: row;
        flex-wrap: wrap;
    }

    .stat {
        min-width: 90px;
    }

    .stat-number {
        font-size: 24px;
    }

    .stat-text {
        font-size: 12px;
    }

    .advantages {
        padding: 50px 0;
    }

    .comparison-table {
        border-radius: 8px;
    }

    .comparison-row {
        grid-template-columns: 1fr;
        gap: 0;
        padding: 30px 20px;
    }

    .comparison-col h4 {
        font-size: 18px;
        margin-bottom: 15px;
    }

    .comparison-list li {
        padding: 10px 0;
        font-size: 13px;
    }

    .theory,
    .process,
    .report-preview,
    .applications,
    .data-support,
    .faq {
        padding: 50px 0;
    }

    h2 {
        font-size: 24px !important;
        margin-bottom: 30px !important;
    }

    .types-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .type-card {
        padding: 20px;
    }

    .type-icon {
        width: 50px;
        height: 50px;
        font-size: 24px;
    }

    .type-card h3 {
        font-size: 16px;
    }

    .type-card p {
        font-size: 13px;
    }

    .type-examples {
        font-size: 12px;
    }

    .steps-container {
        flex-direction: column;
        gap: 10px;
    }

    .step {
        min-width: auto;
        padding: 25px 20px;
    }

    .step-number {
        width: 40px;
        height: 40px;
        font-size: 20px;
    }

    .step h3 {
        font-size: 16px;
        margin-bottom: 10px;
    }

    .step p {
        font-size: 13px;
    }

    .step-detail {
        font-size: 11px;
    }

    .step-arrow {
        transform: rotate(90deg);
        margin: 5px 0;
        font-size: 18px;
    }

    .report-items {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .report-item {
        padding: 20px;
    }

    .report-icon {
        font-size: 32px;
    }

    .report-item h3 {
        font-size: 16px;
    }

    .report-item p {
        font-size: 13px;
    }

    .app-grid {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .app-card {
        padding: 20px;
    }

    .app-card h3 {
        font-size: 16px;
    }

    .app-card p {
        font-size: 13px;
    }

    .data-cards {
        grid-template-columns: repeat(2, 1fr);
        gap: 20px;
    }

    .data-card {
        padding: 25px 15px;
    }

    .data-number {
        font-size: 28px;
    }

    .data-desc {
        font-size: 13px;
    }

    .faq-items {
        max-width: 100%;
    }

    .faq-question {
        font-size: 14px;
    }

    .faq-answer {
        font-size: 13px;
    }

    .cta-section {
        padding: 50px 0;
    }

    .cta-section h2 {
        font-size: 22px;
    }

    .cta-section p {
        font-size: 14px;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 20px;
    }

    .footer-links {
        flex-direction: column;
        gap: 12px;
    }

    .footer-left h3 {
        font-size: 16px;
    }

    .footer-left p {
        font-size: 13px;
    }

    .footer-links a {
        font-size: 13px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 12px;
    }

    .header .container {
        gap: 8px;
        padding: 10px 12px;
    }

    .logo {
        font-size: 14px;
    }

    .nav {
        gap: 8px;
    }

    .nav a {
        font-size: 12px;
    }

    .btn-header {
        padding: 8px 12px;
        font-size: 11px;
    }

    .btn-primary {
        padding: 10px 16px;
        font-size: 12px;
        border-radius: 6px;
        min-height: 44px;
    }

    .btn-large {
        padding: 12px 24px;
        font-size: 13px;
        max-width: 100%;
    }

    .hero {
        padding: 40px 0 30px;
    }

    .hero h1 {
        font-size: 22px;
        margin-bottom: 12px;
    }

    .hero p {
        font-size: 13px;
        margin-bottom: 20px;
    }

    .hero-stats {
        gap: 12px;
    }

    .stat {
        min-width: 80px;
    }

    .stat-number {
        font-size: 20px;
    }

    .stat-text {
        font-size: 11px;
    }

    .advantages {
        padding: 40px 0;
    }

    .comparison-row {
        padding: 20px 15px;
        border-radius: 6px;
    }

    .comparison-col h4 {
        font-size: 16px;
        margin-bottom: 12px;
    }

    .comparison-list li {
        padding: 8px 0;
        font-size: 12px;
    }

    .theory,
    .process,
    .report-preview,
    .applications,
    .data-support,
    .faq {
        padding: 40px 0;
    }

    h2 {
        font-size: 20px !important;
        margin-bottom: 24px !important;
    }

    .section-intro {
        font-size: 13px;
    }

    .types-grid {
        gap: 15px;
    }

    .type-card {
        padding: 16px;
        border-radius: 10px;
    }

    .type-icon {
        width: 44px;
        height: 44px;
        font-size: 20px;
    }

    .type-card h3 {
        font-size: 15px;
        margin-bottom: 8px;
    }

    .type-card p {
        font-size: 12px;
    }

    .type-examples {
        font-size: 11px;
        padding-top: 8px;
        margin-top: 8px;
    }

    .steps-container {
        gap: 5px;
    }

    .step {
        padding: 20px 16px;
        border-radius: 10px;
    }

    .step-number {
        width: 36px;
        height: 36px;
        font-size: 18px;
        margin: 0 auto 12px;
    }

    .step h3 {
        font-size: 15px;
        margin-bottom: 8px;
    }

    .step p {
        font-size: 12px;
    }

    .step-detail {
        font-size: 10px;
        margin-top: 8px;
    }

    .step-arrow {
        font-size: 16px;
        margin: 3px 0;
    }

    .report-items {
        gap: 15px;
    }

    .report-item {
        padding: 16px;
        border-radius: 10px;
    }

    .report-icon {
        font-size: 28px;
        margin-bottom: 12px;
    }

    .report-item h3 {
        font-size: 15px;
        margin-bottom: 8px;
    }

    .report-item p {
        font-size: 12px;
    }

    .app-grid {
        gap: 15px;
    }

    .app-card {
        padding: 16px;
        border-radius: 10px;
        border-left: 3px solid #1e3a8a;
    }

    .app-card h3 {
        font-size: 15px;
        margin-bottom: 8px;
    }

    .app-card p {
        font-size: 12px;
    }

    .data-cards {
        grid-template-columns: 1fr;
        gap: 15px;
    }

    .data-card {
        padding: 20px 15px;
        border-radius: 10px;
    }

    .data-number {
        font-size: 24px;
    }

    .data-desc {
        font-size: 12px;
    }

    .faq-item {
        padding: 15px 0;
    }

    .faq-question {
        font-size: 13px;
    }

    .faq-answer {
        font-size: 12px;
        margin-top: 8px;
    }

    .cta-section {
        padding: 40px 0;
    }

    .cta-section h2 {
        font-size: 20px;
        margin-bottom: 12px;
    }

    .cta-section p {
        font-size: 13px;
        margin-bottom: 20px;
    }

    .footer {
        padding: 30px 0 15px;
    }

    .footer-content {
        gap: 15px;
        margin-bottom: 20px;
    }

    .footer-left h3 {
        font-size: 15px;
        margin-bottom: 6px;
    }

    .footer-left p {
        font-size: 12px;
    }

    .footer-links {
        gap: 10px;
    }

    .footer-links a {
        font-size: 12px;
        padding: 8px 12px;
        border: 1px solid #374151;
        border-radius: 4px;
        display: inline-block;
    }

    .footer-bottom {
        font-size: 11px;
        padding-top: 12px;
    }
}