* { margin: 0; padding: 0; box-sizing: border-box; }
        html { scroll-behavior: smooth; }
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.8;
            color: #333;
            background-color: #f9f9f9;
            background-image: linear-gradient(to bottom, #f0f4f8 0%, #ffffff 100px);
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 15px;
        }
        img { max-width: 100%; height: auto; display: block; }
        .site-header {
            background: linear-gradient(135deg, #1a237e 0%, #283593 50%, #3949ab 100%);
            color: white;
            padding: 1.5rem 0;
            margin-bottom: 2rem;
            border-radius: 0 0 12px 12px;
            box-shadow: 0 4px 20px rgba(26, 35, 126, 0.3);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 0 1rem;
            flex-wrap: wrap;
        }
        .my-logo {
            font-family: 'Georgia', serif;
            font-size: 2.5rem;
            font-weight: bold;
            color: #fff;
            text-decoration: none;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
            transition: transform 0.3s ease, text-shadow 0.3s ease;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .my-logo:hover {
            transform: scale(1.05);
            text-shadow: 3px 3px 6px rgba(0,0,0,0.4);
        }
        .my-logo i { font-size: 2.2rem; }
        .main-nav { display: flex; }
        .nav-links {
            display: flex;
            list-style: none;
            gap: 1.8rem;
            align-items: center;
        }
        .nav-links a {
            color: #e8eaf6;
            text-decoration: none;
            font-weight: 600;
            padding: 0.5rem 0.8rem;
            border-radius: 6px;
            transition: all 0.3s ease;
            white-space: nowrap;
        }
        .nav-links a:hover,
        .nav-links a:focus {
            background-color: rgba(255, 255, 255, 0.2);
            color: #ffffff;
            transform: translateY(-2px);
        }
        .hamburger {
            display: none;
            background: none;
            border: none;
            color: white;
            font-size: 1.8rem;
            cursor: pointer;
            padding: 0.5rem;
        }
        .breadcrumb {
            padding: 1rem 0;
            font-size: 0.9rem;
            color: #666;
            border-bottom: 1px solid #e0e0e0;
            margin-bottom: 2rem;
        }
        .breadcrumb a {
            color: #3949ab;
            text-decoration: none;
        }
        .breadcrumb a:hover { text-decoration: underline; }
        main { display: grid; grid-template-columns: 1fr 300px; gap: 2.5rem; margin-bottom: 3rem; }
        @media (max-width: 768px) { main { grid-template-columns: 1fr; } }
        article { background: white; padding: 2.5rem; border-radius: 12px; box-shadow: 0 6px 18px rgba(0,0,0,0.08); }
        h1 { color: #1a237e; font-size: 2.8rem; margin-bottom: 1.5rem; line-height: 1.2; border-bottom: 3px solid #ffc107; padding-bottom: 0.7rem; }
        h2 { color: #283593; font-size: 2rem; margin: 2.5rem 0 1.2rem; padding-top: 0.5rem; }
        h3 { color: #3949ab; font-size: 1.6rem; margin: 2rem 0 1rem; }
        h4 { color: #5c6bc0; font-size: 1.3rem; margin: 1.5rem 0 0.8rem; }
        p { margin-bottom: 1.5rem; text-align: justify; }
        .lead { font-size: 1.25rem; color: #555; font-weight: 300; }
        b, strong { color: #1a237e; }
        em { font-style: italic; color: #d81b60; }
        .highlight { background-color: #fff9c4; padding: 0.2rem 0.4rem; border-radius: 3px; }
        .emoji { font-size: 1.2em; margin-right: 0.3rem; }
        aside {
            background: #f3f5fd;
            padding: 1.8rem;
            border-radius: 12px;
            align-self: start;
            position: sticky;
            top: 140px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.05);
        }
        .sidebar-widget { margin-bottom: 2.5rem; }
        .sidebar-widget h3 { font-size: 1.4rem; color: #1a237e; margin-bottom: 1.2rem; padding-bottom: 0.5rem; border-bottom: 2px dashed #bbdefb; }
        .toc ul { list-style: none; }
        .toc li { margin-bottom: 0.8rem; }
        .toc a {
            color: #5c6bc0;
            text-decoration: none;
            display: block;
            padding: 0.5rem 0.8rem;
            border-radius: 6px;
            transition: all 0.2s;
        }
        .toc a:hover { background: #e8eaf6; color: #1a237e; padding-left: 1.2rem; }
        .form-container { background: #f8f9fa; padding: 1.8rem; border-radius: 10px; margin: 2.5rem 0; border: 1px solid #e0e0e0; }
        .form-group { margin-bottom: 1.5rem; }
        label { display: block; margin-bottom: 0.5rem; font-weight: 600; color: #444; }
        input, textarea, select {
            width: 100%;
            padding: 0.85rem;
            border: 1px solid #ccc;
            border-radius: 8px;
            font-size: 1rem;
            transition: border 0.3s, box-shadow 0.3s;
        }
        input:focus, textarea:focus, select:focus {
            outline: none;
            border-color: #3949ab;
            box-shadow: 0 0 0 3px rgba(57, 73, 171, 0.2);
        }
        button, .btn {
            background: linear-gradient(to right, #3949ab, #283593);
            color: white;
            border: none;
            padding: 0.9rem 1.8rem;
            border-radius: 8px;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            transition: all 0.3s ease;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
        }
        button:hover, .btn:hover {
            background: linear-gradient(to right, #283593, #1a237e);
            transform: translateY(-3px);
            box-shadow: 0 6px 12px rgba(26, 35, 126, 0.25);
        }
        .rating { display: flex; gap: 0.5rem; margin: 1rem 0; }
        .star { font-size: 1.8rem; color: #ddd; cursor: pointer; transition: color 0.2s; }
        .star:hover,
        .star.active { color: #ffc107; }
        .featured-img {
            margin: 2.5rem auto;
            text-align: center;
            border-radius: 12px;
            overflow: hidden;
            box-shadow: 0 10px 25px rgba(0,0,0,0.1);
        }
        .featured-img img {
            width: 100%;
            max-height: 500px;
            object-fit: cover;
            transition: transform 0.5s ease;
        }
        .featured-img img:hover { transform: scale(1.02); }
        .img-caption {
            font-style: italic;
            color: #666;
            padding: 0.8rem;
            background: #f5f5f5;
            font-size: 0.95rem;
        }
        .article-link {
            color: #1a88ff;
            text-decoration: none;
            border-bottom: 1px dotted #1a88ff;
            font-weight: 500;
        }
        .article-link:hover {
            color: #0d47a1;
            border-bottom-style: solid;
        }
        footer {
            background: #1a237e;
            color: #e8eaf6;
            padding: 3rem 0 2rem;
            border-radius: 12px 12px 0 0;
            margin-top: 4rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2.5rem;
            padding: 0 1.5rem;
        }
        .footer-section h3 { color: #ffc107; font-size: 1.4rem; margin-bottom: 1.5rem; }
        .footer-links { list-style: none; }
        .footer-links li { margin-bottom: 0.8rem; }
        .footer-links a {
            color: #bbdefb;
            text-decoration: none;
            transition: color 0.3s, padding-left 0.3s;
            display: inline-block;
        }
        .footer-links a:hover { color: #ffffff; padding-left: 0.5rem; }
        friend-link {
            display: block;
            background: #283593;
            padding: 1.2rem;
            border-radius: 8px;
            margin: 1rem 0;
            text-align: center;
            font-weight: bold;
        }
        friend-link a { color: #ffc107; text-decoration: none; }
        friend-link a:hover { text-decoration: underline; }
        .copyright {
            text-align: center;
            padding-top: 2rem;
            margin-top: 2rem;
            border-top: 1px solid #3949ab;
            color: #9fa8da;
            font-size: 0.9rem;
        }
        @media (max-width: 992px) {
            h1 { font-size: 2.3rem; }
            h2 { font-size: 1.8rem; }
            .header-container { flex-direction: column; align-items: flex-start; gap: 1.5rem; }
            .main-nav { width: 100%; }
            .nav-links {
                flex-direction: column;
                align-items: flex-start;
                gap: 0.8rem;
                width: 100%;
                display: none;
            }
            .nav-links.active { display: flex; }
            .hamburger { display: block; align-self: flex-end; margin-top: -60px; }
        }
        @media (max-width: 576px) {
            article, aside { padding: 1.5rem; }
            .form-container { padding: 1.2rem; }
            h1 { font-size: 2rem; }
        }
        .text-center { text-align: center; }
        .mt-3 { margin-top: 3rem; }
        .mb-3 { margin-bottom: 3rem; }
        .update-time { font-style: italic; color: #78909c; font-size: 0.95rem; margin-top: 1rem; }