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

        body {
            font-family: 'Arial', sans-serif;
            background: linear-gradient(to bottom, #0a0e27 0%, #1a1a3e 50%, #2d1b4e 100%);
            min-height: 100vh;
            overflow: hidden;
            position: relative;
        }

        /* Stars background */
        .stars {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            pointer-events: none;
        }

        .star {
            position: absolute;
            background: white;
            border-radius: 50%;
            animation: twinkle 3s infinite;
        }

        @keyframes twinkle {
            0%, 100% { opacity: 0.3; }
            50% { opacity: 1; }
        }

        .container {
            max-width: 900px;
            margin: 0 auto;
            padding: 20px;
            position: relative;
            z-index: 10;
            height: 100vh;
            display: flex;
            flex-direction: column;
        }

        .header {
            text-align: center;
            margin-bottom: 15px;
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            padding: 15px;
            border-radius: 15px;
            border: 2px solid rgba(255, 255, 255, 0.2);
        }

        .header h1 {
            color: #fff;
            font-size: 2.2em;
            margin-bottom: 10px;
            text-shadow: 0 0 20px rgba(255, 255, 255, 0.5);
        }

        .progress-info {
            display: flex;
            justify-content: space-around;
            font-size: 1.1em;
            color: #fff;
            margin-top: 10px;
        }

        .progress-item {
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .fuel-bar {
            width: 150px;
            height: 20px;
            background: rgba(255, 255, 255, 0.2);
            border-radius: 10px;
            overflow: hidden;
            border: 2px solid rgba(255, 255, 255, 0.3);
        }

        .fuel-fill {
            height: 100%;
            background: linear-gradient(90deg, #f39c12, #e74c3c);
            transition: width 0.3s;
            box-shadow: 0 0 10px rgba(243, 156, 18, 0.8);
        }

        .game-area {
            flex: 1;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px;
            min-height: 0;
        }

        .question-panel {
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            padding: 25px;
            border-radius: 15px;
            border: 2px solid rgba(255, 255, 255, 0.2);
            display: flex;
            flex-direction: column;
            justify-content: center;
        }

        .question {
            font-size: 2.8em;
            text-align: center;
            color: #fff;
            margin-bottom: 25px;
            font-weight: bold;
            text-shadow: 0 0 20px rgba(255, 255, 255, 0.5);
        }

        .answers {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .answer-btn {
            font-size: 1.8em;
            padding: 18px;
            border: none;
            border-radius: 12px;
            cursor: pointer;
            transition: all 0.3s;
            font-weight: bold;
            color: white;
            box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
            border: 2px solid transparent;
        }

        .answer-btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 6px 20px rgba(255, 255, 255, 0.3);
        }

        .answer-btn.option1 {
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            border-color: rgba(102, 126, 234, 0.5);
        }
        .answer-btn.option2 {
            background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
            border-color: rgba(240, 147, 251, 0.5);
        }
        .answer-btn.option3 {
            background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
            border-color: rgba(79, 172, 254, 0.5);
        }

        .answer-btn.shake {
            animation: shake 0.5s;
        }

        @keyframes shake {
            0%, 100% { transform: translateX(0); }
            25% { transform: translateX(-10px); }
            75% { transform: translateX(10px); }
        }

        .space-panel {
            background: rgba(10, 14, 39, 0.5);
            backdrop-filter: blur(10px);
            border-radius: 15px;
            border: 2px solid rgba(255, 255, 255, 0.2);
            position: relative;
            overflow: hidden;
        }

        .altitude-marker {
            position: absolute;
            right: 10px;
            top: 50%;
            transform: translateY(-50%);
            color: rgba(255, 255, 255, 0.4);
            font-size: 0.9em;
            text-align: right;
        }

        .altitude-line {
            width: 100%;
            height: 1px;
            background: rgba(255, 255, 255, 0.2);
            margin: 5px 0;
        }

        .rocket-container {
            position: absolute;
            bottom: 20px;
            left: 50%;
            transform: translateX(-50%);
            transition: bottom 0.8s ease-out;
        }

        .rocket-container.boost {
            transition: bottom 0.5s ease-out;
        }

        .rocket {
            width: 60px;
            height: 100px;
            position: relative;
        }

        .rocket-body {
            width: 40px;
            height: 70px;
            background: linear-gradient(to bottom, #e74c3c, #c0392b);
            border-radius: 20px 20px 5px 5px;
            position: absolute;
            bottom: 0;
            left: 10px;
            border: 2px solid #a93226;
        }

        .rocket-window {
            width: 20px;
            height: 20px;
            background: #3498db;
            border-radius: 50%;
            position: absolute;
            top: 15px;
            left: 50%;
            transform: translateX(-50%);
            border: 2px solid #2980b9;
            box-shadow: inset 0 0 10px rgba(255, 255, 255, 0.5);
        }

        .rocket-nose {
            width: 0;
            height: 0;
            border-left: 20px solid transparent;
            border-right: 20px solid transparent;
            border-bottom: 30px solid #e74c3c;
            position: absolute;
            top: -28px;
            left: 10px;
        }

        .rocket-wing {
            width: 0;
            height: 0;
            border-top: 20px solid transparent;
            border-bottom: 20px solid transparent;
            position: absolute;
            bottom: 5px;
        }

        .rocket-wing.left {
            border-right: 20px solid #95a5a6;
            left: -15px;
        }

        .rocket-wing.right {
            border-left: 20px solid #95a5a6;
            right: -15px;
        }

        .rocket-flame {
            position: absolute;
            bottom: -30px;
            left: 50%;
            transform: translateX(-50%);
            width: 30px;
            height: 30px;
            background: radial-gradient(circle, #f39c12 0%, #e74c3c 50%, transparent 70%);
            border-radius: 50% 50% 50% 50% / 60% 60% 40% 40%;
            animation: flicker 0.1s infinite;
        }

        .rocket-flame.turbo {
            height: 60px;
            width: 40px;
            bottom: -60px;
            animation: flickerTurbo 0.1s infinite;
            box-shadow: 0 0 30px rgba(243, 156, 18, 0.8);
        }

        @keyframes flicker {
            0%, 100% { opacity: 1; transform: translateX(-50%) scaleY(1); }
            50% { opacity: 0.8; transform: translateX(-50%) scaleY(0.9); }
        }

        @keyframes flickerTurbo {
            0%, 100% { opacity: 1; transform: translateX(-50%) scaleY(1); }
            50% { opacity: 0.9; transform: translateX(-50%) scaleY(1.1); }
        }

        /* Space objects */
        .space-object {
            position: absolute;
            animation: float 5s infinite ease-in-out;
        }

        @keyframes float {
            0%, 100% { transform: translateY(0); }
            50% { transform: translateY(-20px); }
        }

        .planet {
            width: 50px;
            height: 50px;
            border-radius: 50%;
            box-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
        }

        .asteroid {
            width: 30px;
            height: 30px;
            background: #7f8c8d;
            border-radius: 40% 60% 50% 50%;
            box-shadow: 0 0 10px rgba(127, 140, 141, 0.5);
        }

        .collected-item {
            position: absolute;
            font-size: 2em;
            animation: collect 0.8s ease-out forwards;
            pointer-events: none;
        }

        @keyframes collect {
            0% {
                transform: scale(1) translateY(0);
                opacity: 1;
            }
            100% {
                transform: scale(0.3) translateY(-100px);
                opacity: 0;
            }
        }

        .end-screen {
            display: none;
            text-align: center;
            background: rgba(255, 255, 255, 0.1);
            backdrop-filter: blur(10px);
            padding: 40px;
            border-radius: 15px;
            border: 2px solid rgba(255, 255, 255, 0.2);
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            z-index: 100;
            min-width: 400px;
        }

        .end-screen.show {
            display: block;
        }

        .end-screen h2 {
            font-size: 2.5em;
            color: #f39c12;
            margin-bottom: 20px;
            text-shadow: 0 0 20px rgba(243, 156, 18, 0.8);
        }

        .stats {
            font-size: 1.3em;
            color: #fff;
            margin: 20px 0;
        }

        .stats p {
            margin: 10px 0;
        }

        .btn-restart {
            font-size: 1.3em;
            padding: 12px 35px;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
            border: none;
            border-radius: 10px;
            cursor: pointer;
            margin: 10px;
            transition: transform 0.3s;
            border: 2px solid rgba(255, 255, 255, 0.3);
        }

        .btn-restart:hover {
            transform: scale(1.05);
        }

        @media (max-width: 768px) {
            .game-area {
                grid-template-columns: 1fr;
                gap: 10px;
            }

            .header h1 {
                font-size: 1.8em;
            }

            .question {
                font-size: 2.2em;
            }

            .answer-btn {
                font-size: 1.5em;
                padding: 15px;
            }
        }