:root {
            --dsa-color: #6a11cb;    /* Deep Purple */
            --webdev-color: #3b82f6; /* Bright Blue */
            --system-color: #ef4444; /* Vibrant Red */
            --light-text: #f8f8f8;
            --dark-text: #333333;
        }

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

        body {
            font-family: "Poppins", sans-serif;
            background: linear-gradient(135deg, #1f2937, #374151); /* Darker, modern gradient */
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            padding: 40px 20px;
            overflow-x: hidden;
        }

        /* Container holding all cards */
        .container {
            display: flex;
            gap: 30px;
            flex-wrap: wrap;
            justify-content: center;
            align-items: flex-start; /* Align cards at the top */
            width: 100%;
            max-width: 1000px;
        }

        /* ---------------------------------------------------- */
        /* ANIMATIONS */
        /* ---------------------------------------------------- */
        /* Subtle continuous float for an attractive look */
        @keyframes float {
            0%, 100% { transform: translateY(0px) rotate(0deg); }
            50% { transform: translateY(-8px) rotate(-0.5deg); }
        }

        /* Initial load animation */
        @keyframes fadeInScale {
            from { opacity: 0; transform: translateY(30px) scale(0.9); }
            to { opacity: 1; transform: translateY(0) scale(1); }
        }

        /* ---------------------------------------------------- */
        /* CARD STYLING */
        /* ---------------------------------------------------- */
        .card {
            background: var(--light-text);
            width: 100%; /* Full width on tiny screens */
            max-width: 320px;
            padding: 30px;
            border-radius: 20px;
            box-shadow: 0 15px 30px rgba(0, 0, 0, 0.2);
            text-align: center;
            color: var(--dark-text);
            
            /* Animation properties */
            animation: fadeInScale 0.6s ease-out forwards;
            transition: all 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
            
            /* Apply continuous float animation */
            animation-name: float, fadeInScale;
            animation-duration: 5s, 0.6s;
            animation-timing-function: ease-in-out, ease-out;
            animation-iteration-count: infinite, 1;
            animation-fill-mode: forwards;
        }

        /* Staggered animation delay for each card */
        .card:nth-child(1) { animation-delay: 0.1s; }
        .card:nth-child(2) { animation-delay: 0.3s; }
        .card:nth-child(3) { animation-delay: 0.5s; }

        /* Hover: makes the card lift and cast a color glow */
        .card:hover {
            transform: translateY(-12px) scale(1.02);
        }

        .card.dsa:hover { box-shadow: 0 15px 40px rgba(106, 17, 203, 0.5); }
        .card.webdev:hover { box-shadow: 0 15px 40px rgba(59, 130, 246, 0.5); }
        .card.systemdesign:hover { box-shadow: 0 15px 40px rgba(239, 68, 68, 0.5); }


        /* Card Header & Icon */
        .card h2 {
            font-size: clamp(1.5rem, 4vw, 1.8rem);
            margin-bottom: 20px;
            font-weight: 700;
            position: relative;
            padding-bottom: 10px;
        }

        .card h2::after {
            content: '';
            position: absolute;
            left: 50%;
            bottom: 0;
            transform: translateX(-50%);
            width: 60px;
            height: 3px;
            border-radius: 5px;
        }

        .dsa h2 { color: var(--dsa-color); }
        .dsa h2::after { background-color: var(--dsa-color); }

        .webdev h2 { color: var(--webdev-color); }
        .webdev h2::after { background-color: var(--webdev-color); }

        .systemdesign h2 { color: var(--system-color); }
        .systemdesign h2::after { background-color: var(--system-color); }


        /* ---------------------------------------------------- */
        /* OPTION STYLING (CSS-Only Interaction) */
        /* ---------------------------------------------------- */
        .options {
            margin: 20px 0 15px;
            /* Hide the actual radio inputs visually */
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
        }
        
        /* Hide the actual radio input element */
        .options input[type="radio"] {
            position: absolute;
            opacity: 0;
            width: 0;
            height: 0;
        }

        /* Styling for the visible option label (button look) */
        .rating-option {
            display: inline-block;
            margin: 6px;
            padding: 10px 18px;
            border: 2px solid #e5e7eb;
            border-radius: 25px;
            cursor: pointer;
            background-color: #e5e7eb;
            font-size: 14px;
            font-weight: 500;
            color: var(--dark-text);
            transition: all 0.3s;
        }

        /* Hover effect (applies to all visible options) */
        .rating-option:hover {
            border-color: #aaa;
            background-color: #ddd;
        }
        
        /* CSS-Only Selection Logic (uses the radio input's checked state) */
        
        /* DSA SELECTED STATE */
        #dsa-r1:checked ~ .options .rating-option[for="dsa-r1"],
        #dsa-r2:checked ~ .options .rating-option[for="dsa-r2"],
        #dsa-r3:checked ~ .options .rating-option[for="dsa-r3"],
        #dsa-r4:checked ~ .options .rating-option[for="dsa-r4"] {
            background-color: var(--dsa-color);
            color: var(--light-text);
            border-color: var(--dsa-color);
            transform: translateY(-2px) scale(1.05);
        }

        /* WEB DEV SELECTED STATE */
        #webdev-r1:checked ~ .options .rating-option[for="webdev-r1"],
        #webdev-r2:checked ~ .options .rating-option[for="webdev-r2"],
        #webdev-r3:checked ~ .options .rating-option[for="webdev-r3"],
        #webdev-r4:checked ~ .options .rating-option[for="webdev-r4"] {
            background-color: var(--webdev-color);
            color: var(--light-text);
            border-color: var(--webdev-color);
            transform: translateY(-2px) scale(1.05);
        }

        /* SYSTEM DESIGN SELECTED STATE */
        #systemdesign-r1:checked ~ .options .rating-option[for="systemdesign-r1"],
        #systemdesign-r2:checked ~ .options .rating-option[for="systemdesign-r2"],
        #systemdesign-r3:checked ~ .options .rating-option[for="systemdesign-r3"],
        #systemdesign-r4:checked ~ .options .rating-option[for="systemdesign-r4"] {
            background-color: var(--system-color);
            color: var(--light-text);
            border-color: var(--system-color);
            transform: translateY(-2px) scale(1.05);
        }
        
        /* Comment box styling */
        textarea {
            width: 100%;
            height: 70px;
            border-radius: 12px;
            border: 1px solid #ddd;
            margin-top: 15px;
            padding: 10px;
            font-family: 'Poppins', sans-serif;
            resize: none;
            outline: none;
            transition: border 0.3s, box-shadow 0.3s;
        }
        
        /* NEW: Targeted Textarea Focus Colors based on the Card */
        .dsa textarea:focus {
            border: 1px solid var(--dsa-color); 
            box-shadow: 0 0 5px rgba(106, 17, 203, 0.4);
        }
        .webdev textarea:focus {
            border: 1px solid var(--webdev-color); 
            box-shadow: 0 0 5px rgba(59, 130, 246, 0.4);
        }
        .systemdesign textarea:focus {
            border: 1px solid var(--system-color); 
            box-shadow: 0 0 5px rgba(239, 68, 68, 0.4);
        }


        /* Submit buttons (now styled divs) */
        .submit {
            margin-top: 20px;
            width: 100%;
            padding: 12px 20px;
            border: none;
            border-radius: 25px;
            color: white;
            cursor: pointer;
            font-weight: 600;
            transition: background 0.3s, transform 0.3s;
            text-transform: uppercase;
        }

        /* Submit button colors */
        .dsa .submit { background-color: var(--dsa-color); }
        .dsa .submit:hover { background-color: #7c3aed; transform: scale(1.03); }

        .webdev .submit { background-color: var(--webdev-color); }
        .webdev .submit:hover { background-color: #2563eb; transform: scale(1.03); }

        .systemdesign .submit { background-color: var(--system-color); }
        .systemdesign .submit:hover { background-color: #dc2626; transform: scale(1.03); }
        
        /* Thank You Message - HIDDEN as it needs JS to show */
        .thankyou {
            display: none;
        }

        /* ---------------------------------------------------- */
        /* RESPONSIVE ADJUSTMENTS */
        /* ---------------------------------------------------- */
        
        /* Tablet and below (Stack cards) */
        @media (max-width: 768px) {
            .container {
                flex-direction: column;
                gap: 25px;
            }
            .card {
                max-width: 100%;
            }
        }
        
        /* Extra small mobile screens (Squeeze internal padding slightly) */
        @media (max-width: 480px) {
            body {
                padding: 20px 10px; /* Reduced overall page padding */
            }
            .card {
                padding: 20px; /* Reduced card internal padding */
                border-radius: 15px;
            }
            .rating-option {
                padding: 8px 14px; /* Slightly smaller button padding */
                font-size: 13px;
                margin: 4px;
            }
        }

        /* Desktop specific styles for animation consistency */
        @media (min-width: 769px) {
            .card {
                animation: float 5s ease-in-out infinite;
                animation-delay: var(--animation-delay, 0s); 
            }
            .card:nth-child(1) { --animation-delay: 0.1s; }
            .card:nth-child(2) { --animation-delay: 0.3s; }
            .card:nth-child(3) { --animation-delay: 0.5s; }
        }