:root {
    --bg-color: #050505;
    --text-color: #ffffff;
    --accent: #00ffcc;
    --accent-secondary: #ff00ff;
    --glass-bg: rgba(10, 10, 15, 0.4);
    --glass-border: rgba(255, 255, 255, 0.08);
}

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

body, html {
    width: 100%;
    height: 100%;
    font-family: 'Outfit', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    overflow: hidden;
    user-select: none;
}

#game-container {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    background: radial-gradient(circle at center, #111, #000);
}

#game-canvas, #three-canvas {
    display: block;
    width: 100%;
    height: 100%;
}

#three-canvas {
    pointer-events: none;
    z-index: 10;
    position: absolute;
    top: 0;
    left: 0;
}

#bg-canvas {
    display: block;
    width: 100%;
    height: 100%;
    position: absolute;
    top: 0;
    left: 0;
    z-index: -1;
}

#ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 20;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(12px);
    z-index: 100;
    pointer-events: auto;
    transition: opacity 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.screen.hidden {
    opacity: 0;
    pointer-events: none;
    transform: scale(1.05); /* subtle zoom out effect when hiding */
}

.glass-panel {
    background: var(--glass-bg);
    border: 1px solid var(--glass-border);
    border-top: 1px solid rgba(255,255,255,0.2);
    border-left: 1px solid rgba(255,255,255,0.2);
    box-shadow: 0 25px 50px rgba(0,0,0,0.5);
    border-radius: 20px;
    padding: 40px 60px;
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    max-width: 90vw;
}

h1 {
    font-size: 4.5rem;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 2px;
    margin-bottom: 10px;
    background: linear-gradient(135deg, var(--accent), var(--accent-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    filter: drop-shadow(0px 0px 8px rgba(0, 255, 204, 0.4));
}

h2 {
    font-size: 4rem;
    color: #ff3333;
    margin-bottom: 20px;
    text-shadow: 0 0 20px rgba(255, 51, 51, 0.5);
}

p.subtitle {
    font-size: 1.2rem;
    color: #aaa;
    letter-spacing: 4px;
    text-transform: uppercase;
    margin-bottom: 30px;
}

.instruction {
    background: rgba(255,255,255,0.05);
    padding: 15px 30px;
    border-radius: 12px;
    margin-bottom: 30px;
    display: flex;
    align-items: center;
    gap: 15px;
}

.hand-icon {
    font-size: 2rem;
    animation: wave 2s infinite ease-in-out;
}

@keyframes wave {
    0%, 100% { transform: translateX(0); }
    50% { transform: translateX(10px); }
}

.pulsate {
    animation: pulsate 1.5s infinite opacity;
    color: var(--accent);
}

@keyframes pulsate {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

button {
    padding: 16px 48px;
    font-size: 1.5rem;
    font-family: inherit;
    font-weight: 700;
    color: white;
    background: linear-gradient(90deg, #00C9FF 0%, #92FE9D 100%);
    border: none;
    border-radius: 50px;
    cursor: pointer;
    box-shadow: 0 10px 20px rgba(0, 201, 255, 0.3);
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    overflow: hidden;
}

button::before {
    content: '';
    position: absolute;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(255,255,255,0.2);
    transform: translateX(-100%) skewX(-15deg);
    transition: transform 0.5s;
}

button:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 201, 255, 0.5);
}

button:hover::before {
    transform: translateX(100%) skewX(-15deg);
}

button:active {
    transform: translateY(2px);
}

#hud {
    position: absolute;
    top: 30px;
    left: 40px;
    right: 40px;
    display: flex;
    justify-content: space-between;
    z-index: 50;
    transition: opacity 0.3s ease;
}

#hud.hidden {
    opacity: 0;
}

.hud-item {
    background: var(--glass-bg);
    backdrop-filter: blur(8px);
    border: 1px solid var(--glass-border);
    padding: 12px 24px;
    border-radius: 12px;
    font-size: 1.5rem;
    font-weight: 700;
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
    display: flex;
    align-items: center;
    gap: 10px;
}

.score-container span { color: var(--accent); }
.speed-container span { color: var(--accent-secondary); }

.highlight {
    color: var(--accent);
    font-size: 2.5rem;
    font-weight: 900;
}

.settings {
    margin-top: 30px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    color: #94a3b8;
}

input[type=range] {
    -webkit-appearance: none;
    width: 100%;
    background: transparent;
    cursor: pointer;
}

input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 8px;
    background: rgba(255,255,255,0.1);
    border-radius: 4px;
}

input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 20px;
    width: 20px;
    border-radius: 50%;
    background: var(--accent);
    margin-top: -6px;
    box-shadow: 0 0 10px var(--accent);
}

#debug-view {
    position: absolute;
    bottom: 20px;
    right: 20px;
    width: 160px;
    height: 140px;
    background: var(--glass-bg);
    backdrop-filter: blur(5px);
    border-radius: 12px;
    overflow: hidden;
    border: 1px solid var(--glass-border);
    display: flex;
    flex-direction: column;
    box-shadow: 0 10px 20px rgba(0,0,0,0.5);
    z-index: 75;
}

.debug-header {
    background: rgba(0,0,0,0.8);
    color: #888;
    font-size: 0.7rem;
    text-align: center;
    padding: 4px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

#debug-canvas {
    width: 100%;
    flex: 1;
    background-color: #000;
}

@media (max-width: 768px) {
    h1 { font-size: 3rem; }
    h2 { font-size: 2.5rem; }
    .hud-item { font-size: 1.2rem; padding: 8px 16px; }
    #hud { top: 15px; left: 15px; right: 15px; }
    .glass-panel { padding: 30px 20px; width: 90%; }
    button { padding: 12px 30px; font-size: 1.2rem; }
    #debug-view { width: 120px; height: 100px; bottom: 10px; right: 10px; }
}