body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
      'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
      sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    color: #ff0;
    background-color: #000;
}

canvas {
    display: block;
}

#start-screen, #game-over-screen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.8);
    text-align: center;
    cursor: default;
}

#start-content, #game-over-screen h1, #game-over-screen p {
    background-color: #111;
    padding: 2em;
    border: 1px solid #ff0;
    border-radius: 5px;
}

#start-screen h1, #game-over-screen h1 {
    color: #ff0;
    margin-bottom: 0.5em;
}

#start-screen p, #game-over-screen p {
    color: #fff;
    max-width: 400px;
    line-height: 1.5;
}

#start-button, #restart-button {
    margin-top: 1.5em;
    padding: 10px 20px;
    font-size: 1.2em;
    background-color: #ff0;
    color: #000;
    border: none;
    cursor: pointer;
    border-radius: 3px;
    font-weight: bold;
}

#start-button:hover, #restart-button:hover {
    background-color: #ffff80;
}