/* CSS Variables for easy theming */
        :root {
            --primary: #2c3e50;
            --secondary: #3498db;
            --accent: #e74c3c;
            --light: #ecf0f1;
            --dark: #2c3e50;
            --success: #27ae60;
            --warning: #f39c12;
            --danger: #e74c3c;
            --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            --radius: 8px;
        }

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

        body {
            font-family: 'Poppins', sans-serif;
            line-height: 1.6;
            color: var(--dark);
            background-color: #f5f7fa;
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        /* Header Styles */
        header {
            background-color: var(--primary);
            color: white;
            padding: 1rem 0;
            box-shadow: var(--shadow);
            position: sticky;
            top: 0;
            z-index: 100;
        }

        .navbar {
            display: flex;
            justify-content: space-between;
            align-items: center;
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 1rem;
        }

        .logo {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            font-size: 1.5rem;
            font-weight: 600;
        }

        .logo img {
            height: 40px;
        }

        .nav-links {
            display: flex;
            gap: 1.5rem;
        }

        .nav-links a {
            color: white;
            text-decoration: none;
            font-weight: 500;
            transition: color 0.3s;
        }

        .nav-links a:hover {
            color: var(--secondary);
        }

        /* Ad Banner Styles */
        .ad-top {
            background-color: #f0f0f0;
            border: 1px dashed #ccc;
            height: 90px;
            width: 100%;
            max-width: 728px;
            margin: 0 auto;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1rem;
        }

        /* Main Content Styles */
        main {
            flex: 1;
            max-width: 1200px;
            margin: 0 auto;
            padding: 1rem;
            width: 100%;
        }

        h1 {
            color: var(--primary);
            margin-bottom: 1rem;
            text-align: center;
        }

        h2 {
            color: var(--secondary);
            margin: 2rem 0 1rem;
            border-bottom: 2px solid var(--secondary);
            padding-bottom: 0.5rem;
        }

        h3 {
            color: var(--primary);
            margin-bottom: 1rem;
        }

        /* Calculator Grid */
        .calculators-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: 1.5rem;
            margin-bottom: 2rem;
        }

        /* Calculator Card */
        .calculator-card {
            background-color: white;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            padding: 1.5rem;
            transition: transform 0.3s, box-shadow 0.3s;
        }

        .calculator-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
        }

        .calculator-header {
            display: flex;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 1rem;
        }

        .reset-btn {
            background: none;
            border: none;
            color: var(--accent);
            cursor: pointer;
            font-size: 1.2rem;
            transition: transform 0.3s;
        }

        .reset-btn:hover {
            transform: rotate(180deg);
        }

        /* Form Styles */
        .form-group {
            margin-bottom: 1rem;
        }

        label {
            display: block;
            margin-bottom: 0.3rem;
            font-weight: 500;
        }

        input, select {
            width: 100%;
            padding: 0.5rem;
            border: 1px solid #ddd;
            border-radius: var(--radius);
            font-family: inherit;
        }

        input:focus, select:focus {
            outline: none;
            border-color: var(--secondary);
            box-shadow: 0 0 0 2px rgba(52, 152, 219, 0.2);
        }

        button {
            background-color: var(--secondary);
            color: white;
            border: none;
            padding: 0.6rem 1.2rem;
            border-radius: var(--radius);
            cursor: pointer;
            font-weight: 500;
            transition: background-color 0.3s;
            width: 100%;
            margin-top: 0.5rem;
        }

        button:hover {
            background-color: #2980b9;
        }

        .result {
            margin-top: 1rem;
            padding: 0.8rem;
            background-color: var(--light);
            border-radius: var(--radius);
            font-weight: 500;
        }

        .error {
            color: var(--danger);
            font-size: 0.8rem;
            margin-top: 0.2rem;
            display: none;
        }

        /* Sidebar Ad */
        .ad-right {
            display: none;
        }

        /* Content Sections */
        .content-section {
            background-color: white;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            padding: 2rem;
            margin-bottom: 2rem;
        }

        /* Footer Styles */
        footer {
            background-color: var(--primary);
            color: white;
            text-align: center;
            padding: 1.5rem;
            margin-top: 2rem;
        }

        .footer-links {
            display: flex;
            justify-content: center;
            gap: 1.5rem;
            margin-bottom: 1rem;
        }

        .footer-links a {
            color: white;
            text-decoration: none;
        }

        .footer-links a:hover {
            text-decoration: underline;
        }

        .ad-bottom {
            background-color: #f0f0f0;
            border: 1px dashed #ccc;
            height: 90px;
            width: 100%;
            max-width: 728px;
            margin: 0 auto;
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 1rem;
        }

        /* Responsive Styles */
        @media (min-width: 992px) {
            .main-content {
                display: flex;
                gap: 2rem;
            }

            .calculators-container {
                flex: 3;
            }

            .ad-right {
                flex: 1;
                display: flex;
                align-items: center;
                justify-content: center;
                background-color: #f0f0f0;
                border: 1px dashed #ccc;
                height: 600px;
                position: sticky;
                top: 100px;
                align-self: flex-start;
            }
        }

        @media (max-width: 768px) {
            .navbar {
                flex-direction: column;
                gap: 1rem;
            }

            .nav-links {
                flex-wrap: wrap;
                justify-content: center;
            }
        }
        
    /* GATE Section Styles */
    .gate-header {
        margin: 20px 0;
        text-align: center;
    }
    
    .gate-link {
        display: inline-block;
        padding: 10px 20px;
        background-color: #3a7bd5;
        color: white;
        text-decoration: none;
        border-radius: 5px;
        font-weight: bold;
        transition: all 0.3s;
    }
    
    .gate-link:hover {
        background-color: #00d2ff;
        transform: translateY(-2px);
        box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    }
    
    .badge {
        display: inline-block;
        margin-left: 10px;
        padding: 2px 8px;
        background-color: #ff4757;
        color: white;
        border-radius: 10px;
        font-size: 0.8em;
    }
    
    .gate-section {
        padding: 20px;
        margin-top: 30px;
        background-color: #f9f9f9;
        border-radius: 8px;
        box-shadow: 0 2px 10px rgba(0,0,0,0.05);
    }
    
    .controls {
        display: flex;
        justify-content: space-between;
        margin: 20px 0;
        flex-wrap: wrap;
    }
    
    .search-box {
        display: flex;
    }
    
    .search-box input {
        padding: 8px;
        border: 1px solid #ddd;
        border-radius: 4px 0 0 4px;
        width: 200px;
    }
    
    .search-box button {
        padding: 8px 15px;
        background-color: #3a7bd5;
        color: white;
        border: none;
        border-radius: 0 4px 4px 0;
        cursor: pointer;
    }
    
    .stats {
        display: flex;
        justify-content: space-around;
        margin: 20px 0;
        flex-wrap: wrap;
    }
    
    .stat-card {
        text-align: center;
        padding: 15px;
        background: white;
        border-radius: 8px;
        box-shadow: 0 2px 5px rgba(0,0,0,0.1);
        min-width: 100px;
    }
    
    .stat-number {
        font-size: 1.5em;
        font-weight: bold;
        color: #3a7bd5;
    }
    
    .stat-label {
        display: block;
        font-size: 0.9em;
        color: #666;
    }
    
    .question-card {
        background: white;
        border-radius: 8px;
        padding: 20px;
        margin-bottom: 15px;
        box-shadow: 0 2px 5px rgba(0,0,0,0.1);
        position: relative;
    }
    
    .question-card h3 {
        margin-top: 0;
        color: #3a7bd5;
    }
    
    .question-meta {
        display: flex;
        justify-content: space-between;
        font-size: 0.9em;
        color: #666;
        margin-bottom: 15px;
    }
    
    .show-solution {
        display: inline-block;
        padding: 8px 15px;
        background-color: #3a7bd5;
        color: white;
        text-decoration: none;
        border-radius: 4px;
        border: none;
        cursor: pointer;
        transition: background-color 0.3s;
    }
    
    .show-solution:hover {
        background-color: #00d2ff;
    }
    
    .pagination {
        display: flex;
        justify-content: center;
        align-items: center;
        margin-top: 20px;
    }
    
    .pagination button {
        padding: 8px 15px;
        margin: 0 10px;
        background-color: #f1f1f1;
        border: 1px solid #ddd;
        border-radius: 4px;
        cursor: pointer;
    }
    
    .pagination button:disabled {
        opacity: 0.5;
        cursor: not-allowed;
    }
    
    /* Modal Styles */
    .modal {
        display: none;
        position: fixed;
        z-index: 1000;
        left: 0;
        top: 0;
        width: 100%;
        height: 100%;
        background-color: rgba(0,0,0,0.5);
    }
    
    .modal-content {
        background-color: white;
        margin: 5% auto;
        padding: 20px;
        border-radius: 8px;
        width: 80%;
        max-width: 700px;
        max-height: 80vh;
        overflow-y: auto;
        position: relative;
    }
    
    .close-btn {
        position: absolute;
        right: 20px;
        top: 10px;
        font-size: 1.5em;
        cursor: pointer;
    }
    
    .solution-footer {
        margin-top: 20px;
        padding-top: 15px;
        border-top: 1px solid #eee;
        display: flex;
        justify-content: space-between;
        align-items: center;
    }
    
    #explanation-btn {
        padding: 8px 15px;
        background-color: #6c757d;
        color: white;
        border: none;
        border-radius: 4px;
        cursor: pointer;
    }
    
    .stars {
        display: inline-block;
    }
    
    .star {
        font-size: 1.5em;
        color: #ccc;
        cursor: pointer;
        transition: color 0.2s;
    }
    
    .star:hover, .star.active {
        color: #ffc107;
    }