body {
            background-color: #ffffff;
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            color: #333;
            line-height: 1.6;
            margin: 0;
            padding-top: 60px;
        }
        .top-menu {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            background-color: #2c3e50;
            padding: 10px 10px;
            box-shadow: 0 2px 5px rgba(0,0,0,0.1);
            z-index: 1000;
            text-align: center;
        }
        .top-menu a {
            color: #ecf0f1;
            padding: 10px 10px;
            text-decoration: none;
            font-size: 18px;
            transition: background-color 0.3s;
        }
        .top-menu a:hover {
            background-color: #1abc9c;
        }
        .top-menu a.active {
            background-color: #16a085;
        }
        .slide {
            width: 90%;
            max-width: 1200px;
            margin: 40px auto;
            background-color: #f0f0f0;
            border: 1px solid #ccc;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
            display: flex;
            flex-direction: column;
            min-height: 400px;
        }
        .header {
            background-color: #4682B4;
            color: white;
            padding: 5px 10px;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .slide-title {
            font-size: 1.6em;
            font-weight: normal;
            margin: 0;
            text-align: right;
        }
        .slide-number {
            font-weight: bold;
            font-size: 0.9em;
        }
        .content-wrapper {
            display: flex;
            flex-grow: 1;
            align-items: center; /* Vertical centering */
            padding: 25px;
        }
        .content-text {
            flex: 2; /* Occupy 2/3 of the space */
            padding-right: 25px; /* Spacing between text and image area */
            font-size: 1.2em;
            text-align: justify; /* Justified text */
        }
        .content-image {
            flex: 1; /* Occupy 1/3 of the space for illustrations */
            display: flex;
            justify-content: center;
            align-items: center;
        }
        .content-image img {
            max-width: 100%;
            max-height: 100%;
            object-fit: contain;
            border: 1px solid #ddd;
            transition: transform 0.2s;
        }
        .content-image img:hover {
            transform: scale(1.02);
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
        }