:root {
    --bg-color: #1a1a1a;
    --text-color: #ffffff;
    --accent-color: #00d2ff;
    --pipe-color: #444;
    --connected-color: #00d2ff;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

#game-container {
    position: relative;
    width: 100%;
    height: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    background: radial-gradient(circle at center, #2a2a2a 0%, #000000 100%);
}

canvas {
    display: block;
    max-width: 100%;
    max-height: 100%;
    filter: drop-shadow(0 0 20px rgba(0, 210, 255, 0.1));
}

#ui-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

.screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    pointer-events: auto;
    z-index: 10;
    backdrop-filter: blur(5px);
}

.hidden {
    display: none !important;
}

h1 {
    font-size: 4rem;
    margin-bottom: 2rem;
    background: linear-gradient(45deg, #00d2ff, #3a7bd5);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 30px rgba(0, 210, 255, 0.4);
    font-weight: 800;
    letter-spacing: 2px;
}

.mode-select {
    display: flex;
    gap: 20px;
}

.btn {
    background: linear-gradient(45deg, #00d2ff, #3a7bd5);
    border: none;
    padding: 15px 40px;
    margin: 10px;
    border-radius: 30px;
    color: white;
    font-size: 1.2rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    box-shadow: 0 4px 15px rgba(0, 210, 255, 0.3);
}

.btn:hover {
    transform: translateY(-2px) scale(1.05);
    box-shadow: 0 8px 25px rgba(0, 210, 255, 0.6);
}

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

#hud {
    position: absolute;
    top: 20px;
    left: 20px;
    right: 20px;
    display: flex;
    justify-content: space-between;
    font-size: 1.5rem;
    pointer-events: none;
    z-index: 5;
    background: rgba(0, 0, 0, 0.6);
    padding: 15px 30px;
    border-radius: 50px;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

#hud div {
    display: flex;
    align-items: center;
    gap: 10px;
}

#hud span {
    font-weight: bold;
    color: var(--accent-color);
}

#high-scores {
    margin-top: 30px;
    padding: 20px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

#high-scores p {
    margin: 10px 0;
    font-size: 1.2rem;
    color: #ccc;
}

#high-scores span {
    color: var(--accent-color);
    font-weight: bold;
    margin-left: 10px;
}