body {
    background-color: #0d1a26; /* Deep space background */
    font-family: 'Space Mono', monospace; /* Cool space-y font */
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    margin: 0;
    overflow: hidden; /* Hide overflowing stars */
    color: #e0e0e0; /* Light text color for space theme */
}

.stars-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 10% 20%, rgba(255,255,255,.05) 0%, transparent 15%),
                radial-gradient(circle at 70% 80%, rgba(255,255,255,.05) 0%, transparent 20%),
                radial-gradient(circle at 40% 60%, rgba(255,255,255,.05) 0%, transparent 10%);
    animation: twinkle 15s infinite alternate; /* Stars twinkle */
    z-index: -1;
}

@keyframes twinkle {
    0% { opacity: 0.8; }
    50% { opacity: 0.5; }
    100% { opacity: 0.8; }
}

.quiz-container {
    background-color: rgba(30, 48, 64, 0.9); /* Slightly transparent dark blue */
    border-radius: 15px;
    box-shadow: 0 0 25px rgba(0, 200, 255, 0.4); /* Glow effect */
    width: 600px;
    max-width: 90%;
    overflow: hidden;
    position: relative;
    z-index: 1;
}

.quiz-header {
    padding: 2rem;
    position: relative;
}

h2 {
    padding: 1rem;
    text-align: center;
    margin: 0;
    color: #98fb98; /* NASA green for questions */
    font-size: 1.8rem;
    text-shadow: 0 0 10px rgba(152, 251, 152, 0.5); /* Glow for text */
}

ul {
    list-style-type: none;
    padding: 0;
}

ul li {
    font-size: 1.3rem;
    margin: 1.2rem 0;
    transition: background-color 0.3s ease, transform 0.2s ease;
    border-radius: 8px;
    padding: 10px;
}

ul li:hover {
    background-color: rgba(0, 123, 255, 0.2); /* Blue hover color */
    transform: scale(1.02); /* Slightly enlarge on hover */
}

ul li label {
    cursor: pointer;
    display: block;
    padding: 10px;
    color: #e0e0e0;
}

input[type="radio"] {
    margin-right: 15px;
    transform: scale(1.5); /* Larger radio buttons for kids */
    accent-color: #007bff; /* Blue accent for radio buttons */
}

button {
    background-color: #ff5722; /* Rocket orange/red for button */
    color: #ffffff;
    border: none;
    display: block;
    width: 100%;
    cursor: pointer;
    font-size: 1.8rem;
    padding: 1.5rem;
    border-bottom-left-radius: 15px;
    border-bottom-right-radius: 15px;
    text-transform: uppercase;
    font-weight: bold;
    letter-spacing: 2px;
    transition: background-color 0.3s ease, transform 0.2s ease;
    box-shadow: 0 -5px 15px rgba(255, 87, 34, 0.4);
}

button:hover {
    background-color: #e64a19;
    transform: translateY(-2px);
}

.rocket {
    font-size: 4rem;
    position: absolute;
    bottom: -80px; /* Start below the button */
    left: calc(50% - 2rem); /* Center horizontally */
    transform: rotate(-45deg); /* Angle the rocket */
    transition: all 0.6s ease-out; /* Smooth transition for launching */
    text-shadow: 0 0 15px rgba(255, 255, 255, 0.8);
}

.rocket.launch {
    transform: translateY(-500px) rotate(-45deg); /* Launch animation */
    opacity: 0;
}

.correct-answer {
    background-color: rgba(152, 251, 152, 0.2); /* Light green tint */
    border: 2px solid #98fb98; /* NASA green border */
}

.wrong-answer {
    background-color: rgba(255, 99, 71, 0.2); /* Light red tint */
    border: 2px solid #ff6347; /* Tomato red border */
}

.result-screen {
    text-align: center;
    padding: 4rem;
    color: #e0e0e0;
}

.result-screen h2 {
    color: #00bfff; /* Deep sky blue for results */
    font-size: 2.2rem;
    margin-bottom: 2rem;
    text-shadow: 0 0 10px rgba(0, 191, 255, 0.5);
}

.result-screen button {
    background-color: #1e90ff; /* Dodger blue for reload */
    box-shadow: 0 5px 15px rgba(30, 144, 255, 0.4);
    font-size: 1.5rem;
    padding: 1rem 2rem;
    width: auto;
    border-radius: 8px;
    margin-top: 2rem;
}

.result-screen button:hover {
    background-color: #007bff;
    transform: scale(1.05);
}

.explanation {
    font-size: 1rem;
    margin-top: 1rem;
    color: #b0e0e6; /* Powder blue for explanations */
    font-style: italic;
    background-color: rgba(0, 0, 0, 0.3);
    padding: 10px;
    border-radius: 5px;
}