:root {
    --bg-color: #5c94fc;
    /* Mario Sky Blue */
    --text-color: #ffffff;
    --primary-color: #e60012;
    /* Mario Red */
    --secondary-color: #fbd000;
    /* Coin Yellow */
    --font-main: 'Outfit', sans-serif;
}

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

body {
    font-family: var(--font-main);
    background-color: #0d0d12;
    /* Outer dark bg */
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    overflow: hidden;
}

.sky-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(#5c94fc, #85b4ff);
    z-index: -1;
}

.game-container {
    text-align: center;
    position: relative;
    z-index: 10;
}

header {
    margin-bottom: 1rem;
    position: relative;
    text-shadow: 2px 2px 0 rgba(0, 0, 0, 0.2);
}

.back-link {
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    color: white;
    text-decoration: none;
    font-weight: 600;
    background: rgba(0, 0, 0, 0.3);
    padding: 0.5rem 1rem;
    border-radius: 20px;
    transition: background 0.3s;
}

.back-link:hover {
    background: rgba(0, 0, 0, 0.5);
}

h1 {
    font-size: 2.5rem;
    color: white;
    font-family: 'Arial Black', sans-serif;
    /* Blocky font */
    letter-spacing: -1px;
}

.score-board {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    font-weight: 700;
    text-shadow: 1px 1px 0 #000;
}

canvas {
    background: transparent;
    /* Sky is behind */
    /* border: 4px solid #fff; */
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    border-radius: 4px;
    max-width: 100%;
    display: block;
    margin: 0 auto;
}

.instruction {
    margin-top: 1rem;
    color: white;
    font-size: 0.9rem;
    text-shadow: 1px 1px 0 rgba(0, 0, 0, 0.5);
}

.btn {
    margin-top: 1rem;
    padding: 0.8rem 2rem;
    border: none;
    border-radius: 50px;
    background: var(--primary-color);
    color: white;
    font-weight: 700;
    cursor: pointer;
    font-size: 1rem;
    box-shadow: 0 4px 0 #99000c;
    transition: transform 0.1s;
}

.btn:active {
    transform: translateY(4px);
    box-shadow: none;
}

.hidden {
    display: none;
}