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

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: #333;
            padding: 2rem;
        }

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

        h1 {
            text-align: center;
            color: white;
            margin-bottom: 2rem;
            font-size: 2.5rem;
        }

        .section {
            background: white;
            border-radius: 12px;
            padding: 2rem;
            margin-bottom: 2rem;
            box-shadow: 0 10px 30px rgba(0,0,0,0.2);
        }

        h2 {
            color: #667eea;
            margin-bottom: 1rem;
            border-bottom: 3px solid #667eea;
            padding-bottom: 0.5rem;
        }

        h3 {
            color: #764ba2;
            margin: 1.5rem 0 1rem 0;
        }

        .explanation {
            background: #f8f9fa;
            padding: 1rem;
            border-left: 4px solid #667eea;
            margin: 1rem 0;
            border-radius: 4px;
        }

        .demo-box {
            border: 2px solid #ddd;
            border-radius: 8px;
            padding: 1rem;
            margin: 1rem 0;
            background: #fafafa;
        }

        .flex-container {
            background: #e3f2fd;
            border: 3px dashed #2196F3;
            padding: 1rem;
            margin: 1rem 0;
            min-height: 150px;
        }

        .flex-item {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            padding: 1.5rem;
            margin: 0.5rem;
            border-radius: 8px;
            font-weight: bold;
            text-align: center;
            box-shadow: 0 4px 6px rgba(0,0,0,0.1);
        }

        .controls {
            background: #fff3cd;
            padding: 1rem;
            border-radius: 8px;
            margin: 1rem 0;
        }

        .control-group {
            margin: 1rem 0;
        }

        label {
            display: inline-block;
            width: 200px;
            font-weight: bold;
            color: #495057;
        }

        select, button {
            padding: 0.5rem 1rem;
            border: 2px solid #667eea;
            border-radius: 6px;
            background: white;
            cursor: pointer;
            font-size: 1rem;
            transition: all 0.3s;
        }

        select:hover, button:hover {
            background: #667eea;
            color: white;
        }

        button {
            background: #667eea;
            color: white;
            margin: 0 0.5rem;
        }

        button:hover {
            background: #764ba2;
            transform: translateY(-2px);
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
        }

        .code-block {
            background: #1e1e1e;
            color: #d4d4d4;
            padding: 1.5rem;
            border-radius: 8px;
            overflow-x: auto;
            margin: 1rem 0;
            font-family: 'Courier New', monospace;
            position: relative;
        }

        .code-block code {
            font-size: 0.9rem;
            line-height: 1.6;
        }

        .property {
            color: #9cdcfe;
        }

        .value {
            color: #ce9178;
        }

        .comment {
            color: #6a9955;
        }

        .visual-guide {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: 1rem;
            margin: 1rem 0;
        }

        .guide-card {
            background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
            color: white;
            padding: 1.5rem;
            border-radius: 12px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
        }

        .guide-card h4 {
            margin-bottom: 0.5rem;
            font-size: 1.2rem;
        }

        .axis-demo {
            position: relative;
            padding: 2rem;
            background: white;
            border-radius: 8px;
            margin: 1rem 0;
        }

        .axis-line {
            position: absolute;
            background: #ff4081;
            opacity: 0.7;
        }

        .axis-label {
            position: absolute;
            color: #ff4081;
            font-weight: bold;
            font-size: 1.2rem;
        }

        @media (max-width: 768px) {
            body {
                padding: 1rem;
            }
            
            h1 {
                font-size: 1.8rem;
            }
            
            label {
                width: 100%;
                display: block;
                margin-bottom: 0.5rem;
            }
        }