:root {
    --bg-gradient: linear-gradient(135deg, #181715 0%, #24221e 50%, #12110e 100%);
    --ink-color: #e3dec9;
    --light-color: #2a2723;
    --ui-bg: #24221e;
    --ui-hover: #312e29;
    --shadow-color: rgba(0, 0, 0, 0.3);
    --shadow-color-hover: rgba(0, 0, 0, 0.5);
    --vignette-color: rgba(0, 0, 0, 0.5);
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    user-select: none;
}

body {
    background: var(--bg-gradient);
    overflow: hidden;
    font-family: 'Space Mono', monospace;
    color: var(--ink-color);
    transition: background 0.4s ease, color 0.4s ease;
}

#scene-canvas {
    display: block;
    width: 100vw;
    height: 100vh;
}

#ui-layer {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    z-index: 10;
}

.paper-box {
    background: var(--ui-bg);
    border: 2px solid var(--ink-color);
    border-radius: 4px;
    padding: 12px 24px;
    width: 320px; 
    text-align: center;
    font-variant-numeric: tabular-nums;
    box-shadow: 4px 4px 0px var(--shadow-color);
    transition: background-color 0.4s ease, border-color 0.4s ease, box-shadow 0.4s ease;
}

#timer-display {
    font-size: 32px;
    font-weight: 700;
    letter-spacing: -2px;
}

.controls {
    display: flex;
    gap: 12px;
    width: 100%;
}

button {
    flex: 1;
    background: var(--ui-bg);
    border: 2px solid var(--ink-color);
    border-radius: 4px;
    padding: 12px 0;
    font-family: 'Space Mono', monospace;
    font-size: 16px;
    font-weight: 700;
    color: var(--ink-color);
    cursor: pointer;
    text-transform: uppercase;
    transition: transform 0.1s ease, box-shadow 0.1s ease, background-color 0.4s ease, border-color 0.4s ease, color 0.4s ease;
    box-shadow: 3px 3px 0px var(--shadow-color);
}

button:hover {
    background: var(--ui-hover);
    transform: translate(-1px, -1px);
    box-shadow: 4px 4px 0px var(--shadow-color-hover);
}

button:active {
    transform: translate(2px, 2px);
    box-shadow: 1px 1px 0px var(--shadow-color-hover);
}

.vignette {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    pointer-events: none;
    background: radial-gradient(circle at center, rgba(0,0,0,0) 30%, var(--vignette-color) 100%);
    z-index: 5;
    transition: background 0.4s ease;
}

@media (max-width: 600px), (max-height: 500px) {
    .paper-box {
        width: 90vw;
        max-width: 280px;
        padding: 8px 12px;
    }
    #timer-display {
        font-size: 20px;
        letter-spacing: -1px;
    }
    button {
        font-size: 13px;
        padding: 8px 0;
    }
    #ui-layer {
        bottom: 15px;
        gap: 8px;
    }
}