:root {
    --color-bg: #0A1F1C;
    --color-primary: #00B894;
    --color-secondary: #55EFC4;
    --color-accent: #FDCB6E;
    --color-surface: rgba(10, 31, 28, 0.85);
    --color-text: #FFFFFF;
    --glass-bg: rgba(255, 255, 255, 0.05);
    --glass-border: rgba(255, 255, 255, 0.1);
    --shadow-glow: 0 0 15px rgba(0, 184, 148, 0.3);

    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
    --border-radius: 12px;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

body {
    background-color: var(--color-bg);
    color: var(--color-text);
    font-family: var(--font-family);
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}

.game-container {
    position: relative;
    width: 100%;
    height: 100%;
    max-width: 800px;
    max-height: 900px;
    border: 1px solid var(--glass-border);
    box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
    background: radial-gradient(circle at center, #11302C 0%, #0A1F1C 100%);
    overflow: hidden;
}

canvas {
    display: block;
    width: 100%;
    height: 100%;
}

.ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 10;
}

.hud {
    display: flex;
    justify-content: space-between;
    padding: 20px;
    font-weight: 800;
    letter-spacing: 2px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.5);
}

.label {
    color: var(--color-secondary);
    margin-right: 10px;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background: rgba(10, 31, 28, 0.8);
    backdrop-filter: blur(8px);
    transition: opacity 0.3s ease;
    pointer-events: auto;
}

.screen.hidden {
    opacity: 0;
    pointer-events: none;
}

.screen.active {
    opacity: 1;
    pointer-events: auto;
}

.title {
    font-size: 3rem;
    font-weight: 800;
    color: var(--color-primary);
    text-shadow: var(--shadow-glow);
    margin-bottom: 1rem;
    text-align: center;
    letter-spacing: 4px;
}

.instruction {
    color: var(--color-secondary);
    margin-bottom: 3rem;
    font-size: 1.2rem;
    opacity: 0.8;
}

.primary-btn {
    background: var(--glass-bg);
    border: 1px solid var(--color-primary);
    color: var(--color-primary);
    padding: 16px 32px;
    font-size: 1.2rem;
    font-weight: 600;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all 0.2s ease;
    text-transform: uppercase;
    letter-spacing: 2px;
    backdrop-filter: blur(4px);
    box-shadow: 0 4px 15px rgba(0, 184, 148, 0.2);
}

.primary-btn:hover {
    background: var(--color-primary);
    color: var(--color-bg);
    box-shadow: 0 0 20px var(--color-primary);
    transform: translateY(-2px);
}

.primary-btn:active {
    transform: translateY(1px);
}

@media (max-width: 600px) {
    .title {
        font-size: 2rem;
    }
    .hud {
        font-size: 0.9rem;
        padding: 15px;
    }
}