:root {
    --space-deep: #05070a;
    --neon-blue: #00d2ff;
    --neon-purple: #9d50bb;
    --neon-red: #ff416c;
    --text: #e0e0e0;
}

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

body {
    background-color: var(--space-deep);
    color: var(--text);
    font-family: 'Space Grotesk', sans-serif;
    overflow: hidden;
    height: 100vh;
}

.game-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.game-header {
    background: rgba(0,0,0,0.8);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.back-link {
    color: #666;
    text-decoration: none;
    font-weight: bold;
    font-size: 0.9rem;
}

.root-display {
    background: linear-gradient(135deg, var(--neon-blue), var(--neon-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-size: 2.5rem;
    font-weight: 800;
    font-family: 'JetBrains Mono', monospace;
    filter: drop-shadow(0 0 10px rgba(0, 210, 255, 0.4));
}

#root-index {
    font-size: 1.2rem;
    vertical-align: super;
    margin-right: -5px;
}

.stats {
    font-weight: 800;
    color: var(--neon-blue);
    letter-spacing: 2px;
}

/* stage */
#game-stage {
    flex-grow: 1;
    position: relative;
    background-image: radial-gradient(white, rgba(255,255,255,.2) 2px, transparent 40px),
                      radial-gradient(white, rgba(255,255,255,.15) 1px, transparent 30px);
    background-size: 550px 550px, 350px 350px;
    background-position: 0 0, 40px 60px;
}

#asteroidsCanvas {
    display: block;
}

/* Overlay */
.overlay {
    position: absolute;
    inset: 0;
    background: rgba(0,0,0,0.85);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 100;
}

.overlay.hidden {
    display: none;
}

.content {
    text-align: center;
    max-width: 600px;
    padding: 3rem;
    border: 1px solid rgba(255,255,255,0.1);
    border-radius: 20px;
    background: rgba(10, 10, 20, 0.5);
    backdrop-filter: blur(10px);
}

h1 {
    font-size: 4rem;
    margin-bottom: 1rem;
    background: linear-gradient(90deg, #fff, var(--neon-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    font-weight: 900;
}

.btn-space {
    background: transparent;
    border: 2px solid var(--neon-blue);
    color: var(--neon-blue);
    padding: 1.2rem 3rem;
    font-size: 1.2rem;
    font-weight: 800;
    cursor: pointer;
    margin-top: 2rem;
    border-radius: 50px;
    transition: 0.3s;
    font-family: 'Space Grotesk', sans-serif;
}

.btn-space:hover {
    background: var(--neon-blue);
    color: #000;
    box-shadow: 0 0 30px var(--neon-blue);
}

.controls-guide {
    margin-top: 2.5rem;
    color: #888;
    font-size: 0.9rem;
}