:root {
    --bg-gradient-start: #1a237e;
    --bg-gradient-end: #283593;
    --text-color: #ffffff;
    --primary-color: #4fc3f7;
    --primary-color-dark: #0093c4;
    --card-bg: rgba(255, 255, 255, 0.05);
}

html,
body {
    height: 100%;
    margin: 0;
    padding: 0;
    overflow: hidden;
    font-family: 'Poppins', sans-serif;
    background-color: var(--bg-gradient-start);
}

header {
    position: fixed;
    top: 0;
    left: 0;
    padding: 20px;
    z-index: 100;
}

.logo img {
    height: 48px;
    width: auto;
    object-fit: contain;
    transition: transform 0.3s ease;
}

.logo img:hover {
    transform: scale(1.05);
}

.container {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    width: 100vw;
    padding: 20px;
    box-sizing: border-box;
    background: linear-gradient(160deg, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 100%);
    color: var(--text-color);
    text-align: center;
}

.screen {
    display: flex;
    flex-direction: column;
    justify-content: space-around;
    align-items: center;
    width: 100%;
    height: 100%;
}

.hidden {
    display: none;
}

h1 {
    font-size: 2.5rem;
    font-weight: 700;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

h2 {
    font-size: 1.8rem;
    font-weight: 600;
    padding: 0 1rem;
}

.main-btn {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-color);
    background-color: var(--primary-color);
    border: none;
    border-radius: 50px;
    padding: 20px 40px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.main-btn:hover {
    background-color: var(--primary-color-dark);
    transform: translateY(-3px);
}

#game-screen {
    justify-content: space-between;
}

#timer {
    font-size: 3rem;
    font-weight: 700;
    color: var(--primary-color);
    background-color: var(--card-bg);
    width: 100px;
    height: 100px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    box-shadow: inset 0 0 15px rgba(0, 0, 0, 0.2);
    margin-top: 5vh;
}

#question-container {
    flex-grow: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

#answers-container {
    display: flex;
    flex-direction: column;
    width: 100%;
    gap: 15px;
    margin-bottom: 5vh;
}

.answer-btn {
    width: 100%;
    padding: 18px;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-color);
    background-color: var(--card-bg);
    border: 2px solid var(--primary-color);
    border-radius: 15px;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.answer-btn:hover {
    background-color: rgba(79, 195, 247, 0.3);
}

.answer-btn.correct {
    background-color: #10b981;
    /* Vert */
    border-color: #10b981;
}

.answer-btn.incorrect {
    background-color: #ef4444;
    /* Rouge */
    border-color: #ef4444;
}

#result-screen p {
    font-size: 1.2rem;
    padding: 0 1rem;
}

/* Star Border Animation */
@property --angle {
    syntax: '<angle>';
    initial-value: 0deg;
    inherits: false;
}

.main-btn.star-border {
    position: relative;
    background: transparent;
    /* We rebuild background with ::after */
    z-index: 0;
    overflow: hidden;
    /* Clean edges */
}

/* The spinning gradient border */
.main-btn.star-border::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
    height: 100%;
    padding: 4px;
    /* Thickness of the border */
    border-radius: 54px;
    /* Match button radius + padding */
    background: conic-gradient(from var(--angle), transparent 75%, #ffffff);
    z-index: -1;
    animation: spin 3s linear infinite;
}

/* The button background */
.main-btn.star-border::after {
    content: '';
    position: absolute;
    inset: 4px;
    /* Match padding of ::before */
    background: var(--primary-color);
    border-radius: 50px;
    z-index: -1;
}

.main-btn.star-border:hover::after {
    background-color: var(--primary-color-dark);
}

@keyframes spin {
    from {
        --angle: 0deg;
    }

    to {
        --angle: 360deg;
    }
}