* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            background-color: #f8f9fa;
            color: #333;
            line-height: 1.7;
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }
        a {
            color: #2a6ebb;
            text-decoration: none;
            transition: color 0.3s ease;
        }
        a:hover {
            color: #e63946;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        .container {
            width: 100%;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 20px;
        }
        header {
            background: linear-gradient(135deg, #1e3c72, #2a5298);
            color: white;
            padding: 1rem 0;
            box-shadow: 0 4px 12px rgba(0,0,0,0.1);
            position: sticky;
            top: 0;
            z-index: 1000;
        }
        .header-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .my-logo a {
            font-size: 2rem;
            font-weight: 800;
            color: white;
            text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .my-logo i {
            color: #4dabf7;
        }
        nav ul {
            display: flex;
            list-style: none;
            gap: 2rem;
        }
        nav a {
            color: white;
            font-weight: 600;
            padding: 0.5rem 0.8rem;
            border-radius: 4px;
        }
        nav a:hover, nav a.active {
            background-color: rgba(255,255,255,0.15);
        }
        .hamburger {
            display: none;
            font-size: 1.8rem;
            cursor: pointer;
            background: none;
            border: none;
            color: white;
        }
        .breadcrumb {
            background-color: #e9ecef;
            padding: 1rem;
            font-size: 0.9rem;
            margin-bottom: 2rem;
            border-radius: 4px;
        }
        .breadcrumb a {
            color: #495057;
        }
        .breadcrumb a:hover {
            color: #1e3c72;
        }
        .breadcrumb span {
            color: #6c757d;
        }
        main {
            flex: 1;
            padding: 2rem 0;
        }
        article {
            background-color: white;
            padding: 2.5rem;
            border-radius: 12px;
            box-shadow: 0 6px 15px rgba(0,0,0,0.05);
            margin-bottom: 2rem;
        }
        h1 {
            font-size: 2.8rem;
            color: #1e3c72;
            margin-bottom: 1.5rem;
            line-height: 1.2;
            border-bottom: 3px solid #ffd166;
            padding-bottom: 0.5rem;
        }
        h2 {
            font-size: 2rem;
            color: #2a5298;
            margin: 2.5rem 0 1rem;
            padding-bottom: 0.5rem;
            border-bottom: 2px dashed #a2d2ff;
        }
        h3 {
            font-size: 1.5rem;
            color: #3a6ea5;
            margin: 2rem 0 1rem;
        }
        h4 {
            font-size: 1.2rem;
            color: #4a8bc2;
            margin: 1.5rem 0 0.8rem;
        }
        p {
            margin-bottom: 1.2rem;
            font-size: 1.1rem;
            text-align: justify;
        }
        .intro {
            font-size: 1.3rem;
            color: #555;
            background-color: #f1faee;
            padding: 1.5rem;
            border-left: 5px solid #457b9d;
            border-radius: 0 8px 8px 0;
            margin-bottom: 2rem;
        }
        .highlight {
            background-color: #ffefc6;
            padding: 1rem;
            border-radius: 8px;
            margin: 1.5rem 0;
            border-left: 4px solid #e63946;
        }
        .tool-box {
            background: linear-gradient(to right, #e3f2fd, #f3e5f5);
            padding: 1.5rem;
            border-radius: 10px;
            margin: 2rem 0;
            border: 1px solid #bbdefb;
        }
        .functional-forms {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 2rem;
            margin: 3rem 0;
        }
        .form-card {
            background: white;
            padding: 1.8rem;
            border-radius: 10px;
            box-shadow: 0 4px 10px rgba(0,0,0,0.08);
        }
        .form-card h3 {
            margin-top: 0;
            display: flex;
            align-items: center;
            gap: 10px;
            color: #1e3c72;
        }
        .form-card form {
            display: flex;
            flex-direction: column;
            gap: 1rem;
        }
        input, textarea, select {
            padding: 0.8rem;
            border: 1px solid #ced4da;
            border-radius: 6px;
            font-size: 1rem;
            width: 100%;
        }
        button {
            background: linear-gradient(to right, #1e3c72, #2a5298);
            color: white;
            border: none;
            padding: 0.9rem 1.5rem;
            border-radius: 6px;
            font-weight: 600;
            cursor: pointer;
            transition: transform 0.3s, box-shadow 0.3s;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 8px;
        }
        button:hover {
            transform: translateY(-3px);
            box-shadow: 0 6px 12px rgba(30, 60, 114, 0.3);
        }
        .featured-img {
            margin: 2.5rem 0;
            text-align: center;
        }
        .featured-img img {
            border-radius: 12px;
            box-shadow: 0 8px 20px rgba(0,0,0,0.15);
            max-width: 800px;
            margin: 0 auto;
        }
        .img-caption {
            font-style: italic;
            color: #666;
            margin-top: 0.8rem;
            font-size: 0.95rem;
        }
        .internal-links {
            background-color: #f8f9fa;
            padding: 1.5rem;
            border-radius: 10px;
            margin: 2rem 0;
        }
        .internal-links ul {
            columns: 2;
            list-style-position: inside;
        }
        .internal-links li {
            margin-bottom: 0.7rem;
        }
        footer {
            background-color: #1e3c72;
            color: #e9ecef;
            padding: 3rem 0 1.5rem;
            margin-top: 3rem;
        }
        .footer-content {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
            gap: 2rem;
            margin-bottom: 2rem;
        }
        .footer-section h4 {
            color: #ffd166;
            margin-bottom: 1.2rem;
            font-size: 1.3rem;
        }
        .footer-links a {
            color: #b3d9ff;
            display: block;
            margin-bottom: 0.8rem;
        }
        .footer-links a:hover {
            color: white;
            padding-left: 5px;
        }
        friend-link {
            display: block;
            background-color: rgba(255,255,255,0.05);
            padding: 1rem;
            border-radius: 6px;
            margin: 1rem 0;
            border-left: 4px solid #4dabf7;
        }
        .copyright {
            text-align: center;
            padding-top: 1.5rem;
            border-top: 1px solid #2a5298;
            font-size: 0.9rem;
            color: #adb5bd;
        }
        @media (max-width: 992px) {
            h1 { font-size: 2.4rem; }
            h2 { font-size: 1.8rem; }
            .header-container { padding: 0 1rem; }
        }
        @media (max-width: 768px) {
            .hamburger { display: block; }
            nav ul {
                display: none;
                flex-direction: column;
                position: absolute;
                top: 100%;
                left: 0;
                width: 100%;
                background-color: #2a5298;
                padding: 1rem;
                box-shadow: 0 10px 15px rgba(0,0,0,0.1);
            }
            nav ul.active { display: flex; }
            nav li { margin: 0.5rem 0; }
            .functional-forms { grid-template-columns: 1fr; }
            .internal-links ul { columns: 1; }
            article { padding: 1.5rem; }
        }
        @media (max-width: 576px) {
            h1 { font-size: 2rem; }
            h2 { font-size: 1.6rem; }
            .intro { font-size: 1.1rem; }
            .my-logo a { font-size: 1.6rem; }
        }