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

body {
    background: linear-gradient(#0b1d3a, #000);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.menu-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: linear-gradient(#0b1d3a, #000);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
}

.title-container {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 30px;
}

.logo {
    width: 60px;
}

.menu-buttons button {
    display: block;
    margin: 10px;
    padding: 10px 20px;
    font-size: 18px;
    cursor: pointer;
}

.menu-content {
    margin-top: 20px;
    max-width: 300px;
    text-align: center;
}

.hidden {
    display: none;
}

.game-board {
    width: 1200px;
    height: 500px;
    border: 15px solid green;
    position: relative;
    overflow: hidden;
    background: linear-gradient(#87CEEB, #E0F6FF);
}

.akaza {
    position: absolute;
    bottom: 0;
    width: 80px;
    right: -80px;
    animation: akaza-animation 1.5s infinite linear; 
}

.rengoku {
    width: 80px;
    left: 20px;
    position: absolute;
    bottom: -5px;
}

.jump {
    animation: jump 500ms ease-out;
}

.clouds {
    position: absolute;
    width: 300px;
    margin-top: 20px;
    animation: clouds-animation 20s infinite linear;
}

.score {
    position: absolute;
    top: 10px;
    right: 20px;
    font-size: 24px;
    color: black;
    font-family: Arial, sans-serif;
}

.game-over {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.6);
    color: white;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    font-family: Arial;
}

.hidden {
    display: none;
}

.game-over button {
    padding: 10px 20px;
    font-size: 18px;
    margin-top: 20px;
    cursor: pointer;
}

@keyframes akaza-animation {
    from {
        right: 0;
    }

    to {
        right: 100%;
    }
}

@keyframes jump {
    0% {
        bottom: 0%;
    }

    40% {
        bottom: 180px;
    }

    50% {
        bottom: 180px;
    }

    60% {
        bottom: 180px;
    }

    100% {
        bottom: 0;
    }
}

@keyframes clouds-animation {
    from {
        right: -300px;
    }

    to {
        right: 100%;
    }
}


@media (max-width: 768px) {

    .game-board {
        height: 400px;
        border-width: 10px;
    }

    .rengoku {
        width: 70px;
        left: 15px;
    }

    .akaza {
        width: 70px;
    }

    .clouds {
        width: 250px;
    }

    .score {
        font-size: 20px;
        right: 15px;
    }

    .menu-screen {
        height: 100vh;
    }

    .menu-buttons button {
        font-size: 16px;
        padding: 8px 16px;
    }

    .logo {
        width: 50px;
    }
}



@media (max-width: 480px) {

    .game-board {
        height: 300px;
        border-width: 8px;
    }

    .rengoku {
        width: 60px;
        left: 10px;
    }

    .akaza {
        width: 60px;
    }

    .clouds {
        width: 200px;
    }

    .score {
        font-size: 18px;
        top: 5px;
        right: 10px;
    }

    .menu-screen {
        height: 100vh;
        padding: 20px;
    }

    .title-container {
        flex-direction: column;
        gap: 10px;
    }

    .logo {
        width: 40px;
    }

    .menu-buttons button {
        width: 100%;
        font-size: 16px;
        padding: 12px;
    }

    .game-over h1 {
        font-size: 24px;
    }

    .game-over button {
        width: 80%;
        font-size: 16px;
    }
}