* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

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

a {
    color: #2563eb;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

.site-header {
    background-color: #fff;
    border-bottom: 1px solid #e5e7eb;
    padding: 15px 0;
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 20px;
    font-weight: 700;
    color: #1f2937;
    text-decoration: none;
}

.logo:hover {
    text-decoration: none;
    color: #2563eb;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-toggle span {
    width: 25px;
    height: 3px;
    background-color: #1f2937;
    margin: 3px 0;
    transition: 0.3s;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 30px;
}

.main-nav a {
    color: #4b5563;
    font-weight: 500;
    font-size: 15px;
    padding: 8px 0;
    display: block;
}

.main-nav a:hover {
    color: #2563eb;
    text-decoration: none;
}

.hero-banner {
    background: #1f2937;
    color: #fff;
    padding: 80px 0;
}

.banner-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.banner-text h1 {
    font-size: 42px;
    line-height: 1.2;
    margin-bottom: 20px;
    font-weight: 700;
}

.banner-text p {
    font-size: 18px;
    line-height: 1.7;
    margin-bottom: 30px;
    opacity: 0.95;
}

.btn-primary {
    display: inline-block;
    background-color: #fff;
    color: #1f2937;
    padding: 14px 32px;
    border-radius: 6px;
    font-weight: 600;
    font-size: 16px;
    text-decoration: none;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    text-decoration: none;
}

.banner-image img {
    width: 100%;
    height: auto;
    border-radius: 8px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.2);
}

.content-section {
    padding: 80px 0;
}

.gray-bg {
    background-color: #f9fafb;
}

.content-section h2 {
    font-size: 36px;
    margin-bottom: 40px;
    color: #1f2937;
    font-weight: 700;
}

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

.card {
    background-color: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    transition: box-shadow 0.3s, transform 0.3s;
}

.card:hover {
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    transform: translateY(-5px);
}

.card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.card-content {
    padding: 25px;
}

.card-content h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: #1f2937;
    font-weight: 600;
}

.card-content h3 a {
    color: #1f2937;
    text-decoration: none;
}

.card-content h3 a:hover {
    color: #2563eb;
    text-decoration: none;
}

.card-content p {
    color: #6b7280;
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: 15px;
}

.category {
    display: inline-block;
    background-color: #e5e7eb;
    color: #374151;
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 13px;
    font-weight: 600;
}

.site-footer {
    background-color: #1f2937;
    color: #d1d5db;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: #fff;
    font-size: 18px;
    margin-bottom: 15px;
    font-weight: 600;
}

.footer-section p {
    font-size: 14px;
    line-height: 1.6;
}

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

.footer-section ul li {
    margin-bottom: 10px;
}

.footer-section a {
    color: #d1d5db;
    font-size: 14px;
    text-decoration: none;
}

.footer-section a:hover {
    color: #fff;
    text-decoration: underline;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 20px;
    text-align: center;
}

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

.article-header {
    padding: 60px 0 40px;
    background-color: #f9fafb;
    border-bottom: 1px solid #e5e7eb;
}

.article-header h1 {
    font-size: 42px;
    color: #1f2937;
    margin-bottom: 15px;
    line-height: 1.2;
    font-weight: 700;
}

.article-meta {
    color: #6b7280;
    font-size: 15px;
}

.article-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 60px 20px;
}

.article-content h2 {
    font-size: 32px;
    color: #1f2937;
    margin-top: 50px;
    margin-bottom: 20px;
    font-weight: 700;
}

.article-content h3 {
    font-size: 24px;
    color: #1f2937;
    margin-top: 35px;
    margin-bottom: 15px;
    font-weight: 600;
}

.article-content p {
    font-size: 17px;
    line-height: 1.8;
    color: #374151;
    margin-bottom: 20px;
}

.related-articles {
    margin-top: 80px;
    padding-top: 60px;
    border-top: 2px solid #e5e7eb;
}

.related-articles h2 {
    font-size: 28px;
    color: #1f2937;
    margin-bottom: 30px;
    font-weight: 700;
}

.related-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.related-card {
    background-color: #f9fafb;
    border-radius: 8px;
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    border: 1px solid #e5e7eb;
}

.related-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
}

.related-card img {
    width: 100%;
    height: 150px;
    object-fit: cover;
}

.related-card-content {
    padding: 20px;
}

.related-card h3 {
    font-size: 16px;
    margin-bottom: 8px;
    line-height: 1.4;
}

.related-card h3 a {
    color: #1f2937;
    text-decoration: none;
}

.related-card h3 a:hover {
    color: #2563eb;
}

.related-card p {
    font-size: 14px;
    color: #6b7280;
    line-height: 1.5;
    margin-bottom: 0;
}

.related-card:nth-child(4) {
    display: none;
}

.article-content ul,
.article-content ol {
    margin-bottom: 20px;
    padding-left: 30px;
}

.article-content li {
    font-size: 17px;
    line-height: 1.8;
    color: #374151;
    margin-bottom: 10px;
}

.article-content img {
    width: 100%;
    max-width: 700px;
    height: auto;
    margin: 30px 0;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.article-content code {
    background-color: #f3f4f6;
    padding: 3px 8px;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 15px;
    color: #e11d48;
}

.article-content pre {
    background-color: #1f2937;
    color: #f9fafb;
    padding: 20px;
    border-radius: 8px;
    overflow-x: auto;
    margin: 25px 0;
}

.article-content pre code {
    background: none;
    padding: 0;
    color: #f9fafb;
    font-size: 14px;
}

.note-box {
    background-color: #fef3c7;
    border-left: 4px solid #f59e0b;
    padding: 20px;
    margin: 30px 0;
    border-radius: 4px;
}

.note-box p {
    margin-bottom: 0;
}

.search-container {
    max-width: 700px;
    margin: 60px auto;
    padding: 0 20px;
}

.search-box {
    position: relative;
    margin-bottom: 40px;
}

.search-input {
    width: 100%;
    padding: 16px 20px;
    font-size: 18px;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    outline: none;
}

.search-input:focus {
    border-color: #2563eb;
}

.search-results {
    margin-top: 30px;
}

.search-result-item {
    background-color: #fff;
    border: 1px solid #e5e7eb;
    border-radius: 8px;
    padding: 25px;
    margin-bottom: 20px;
    transition: box-shadow 0.3s;
}

.search-result-item:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.search-result-item h3 {
    font-size: 22px;
    margin-bottom: 10px;
}

.search-result-item h3 a {
    color: #2563eb;
    text-decoration: none;
}

.search-result-item h3 a:hover {
    text-decoration: underline;
}

.search-result-item p {
    color: #6b7280;
    font-size: 15px;
    line-height: 1.6;
}

.legal-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 60px 20px;
}

.legal-content h1 {
    font-size: 42px;
    color: #1f2937;
    margin-bottom: 30px;
    font-weight: 700;
}

.legal-content h2 {
    font-size: 28px;
    color: #1f2937;
    margin-top: 40px;
    margin-bottom: 15px;
    font-weight: 600;
}

.legal-content h3 {
    font-size: 22px;
    color: #374151;
    margin-top: 30px;
    margin-bottom: 12px;
    font-weight: 600;
}

.legal-content p {
    font-size: 16px;
    line-height: 1.8;
    color: #4b5563;
    margin-bottom: 18px;
}

.legal-content ul {
    margin-bottom: 18px;
    padding-left: 30px;
}

.legal-content li {
    font-size: 16px;
    line-height: 1.8;
    color: #4b5563;
    margin-bottom: 8px;
}

.contact-form {
    max-width: 600px;
    margin: 40px auto;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: #374151;
    font-size: 15px;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 15px;
    font-family: inherit;
    outline: none;
}

.form-group input:focus,
.form-group textarea:focus {
    border-color: #2563eb;
}

.form-group textarea {
    min-height: 150px;
    resize: vertical;
}

.btn-submit {
    background-color: #2563eb;
    color: #fff;
    padding: 14px 32px;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.3s;
}

.btn-submit:hover {
    background-color: #1d4ed8;
}

@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: flex;
    }

    .main-nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: #fff;
        border-top: 1px solid #e5e7eb;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
        display: none;
    }

    .main-nav.active {
        display: block;
    }

    .main-nav ul {
        flex-direction: column;
        gap: 0;
        height: 100vh;
        padding: 15px 0;
    }

    .main-nav li {
        border-bottom: 1px solid #f3f4f6;
    }

    .main-nav a {
        padding: 15px 20px;
    }

    .banner-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .banner-text h1 {
        font-size: 32px;
    }

    .banner-text p {
        font-size: 16px;
    }

    .hero-banner {
        padding: 50px 0;
    }

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

    .content-section h2 {
        font-size: 28px;
    }

    .card-grid {
        grid-template-columns: 1fr;
        gap: 25px;
    }

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

    .related-card:nth-child(4) {
        display: block;
    }

    .footer-content {
        grid-template-columns: 1fr;
        gap: 30px;
    }

    .article-header h1 {
        font-size: 32px;
    }

    .article-content h2 {
        font-size: 26px;
    }

    .article-content h3 {
        font-size: 20px;
    }

    .article-content p,
    .article-content li {
        font-size: 16px;
    }

    .btn-primary {
        padding: 12px 24px;
        font-size: 15px;
    }

    .search-input {
        font-size: 16px;
        padding: 14px 18px;
    }

    .legal-content h1 {
        font-size: 32px;
    }

    .legal-content h2 {
        font-size: 24px;
    }
}

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

    .banner-text h1 {
        font-size: 26px;
    }

    .banner-text p {
        font-size: 15px;
    }

    .content-section h2 {
        font-size: 24px;
        margin-bottom: 30px;
    }

    .article-header {
        padding: 40px 0 30px;
    }

    .article-header h1 {
        font-size: 26px;
    }

    .article-content {
        padding: 40px 15px;
    }

    .btn-primary {
        display: block;
        text-align: center;
    }
}