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

html,
body {
    height: 100%;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    display: flex;
    justify-content: center;
    align-items: center;
    overflow: hidden;
    color: #e0e0e0;
}

.game-container {
    display: flex;
    flex-direction: column;
    width: calc(100vw - 10px);
    height: calc(100vh - 10px);
    padding: 10px 15px;
    text-align: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

h1 {
    font-size: 1.8rem;
    margin-bottom: 8px;
    color: #00d26a;
    text-shadow: 0 0 15px rgba(0, 210, 106, 0.5);
}

.score-board {
    width: 100%;
    display: flex;
    justify-content: center;
    gap: 80px;
    font-size: 1.4rem;
    padding: 6px 5px;
    margin-bottom: 8px;
}

.score-board span {
    background: rgba(0, 0, 0, 0.3);
    padding: 8px 20px;
    border-radius: 20px;
}

#score {
    color: #00d26a;
    font-weight: bold;
}

#highscore {
    color: #ffd700;
    font-weight: bold;
}

.board-wrap {
    flex: 1;
    min-height: 0;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
}

#gameCanvas {
    border: 3px solid #00d26a;
    border-radius: 10px;
    background-color: #0a0a0a;
    display: block;
    max-width: 100%;
    max-height: 100%;
}

#message {
    margin: 10px 0;
    font-size: 1rem;
    color: #ffcc00;
    min-height: 1.5em;
}

#restartBtn {
    align-self: center;
    padding: 12px 30px;
    font-size: 1.1rem;
    font-weight: bold;
    background: #00d26a;
    color: #0a0a0a;
    border: none;
    border-radius: 25px;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
    display: none;
}

#restartBtn:hover {
    transform: scale(1.05);
    box-shadow: 0 0 20px rgba(0, 210, 106, 0.6);
}