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

body {
    background: skyblue;
    font-family: sans-serif;

    display: flex;
    justify-content: center;   /* center horizontally */
    align-items: flex-start;   /* stick to top */
    padding-top: 40px;         /* space from top */
}


.game {
    position: relative;
    width: 300px;
    height: 300px;
}

/* Mario */
#mario {
    width: 80px;
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
}

/* Brick */
#brick {
    width: 80px;
    position: absolute;
    bottom: 120px;
    left: 50%;
    transform: translateX(-50%);
}

/* Coin */
#coin {
    width: 40px;
    position: absolute;
    bottom: 140px;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
}


.jump {
    animation: jump 0.6s ease;
}

@keyframes jump {
    0% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(-150px);
    }
    100% {
        transform: translateX(-50%) translateY(0);
    }
}

.hit {
    animation: hit 0.3s ease;
}

@keyframes hit {
    0% {
        transform: translateX(-50%) translateY(0);
    }
    50% {
        transform: translateX(-50%) translateY(-20px);
    }
    100% {
        transform: translateX(-50%) translateY(0);
    }
}


.coin-show {
    animation: coin 0.6s ease;
}

@keyframes coin {
    0% {
        transform: translateX(-50%) translateY(0);
        opacity: 1;
    }
    50% {
        transform: translateX(-50%) translateY(-100px) rotate(360deg);
    }
    100% {
        transform: translateX(-50%) translateY(0);
        opacity: 0;
    }
}

button {
    position: absolute;
    bottom: -60px;
    left: 50%;
    transform: translateX(-50%);
    padding: 10px 20px;
    font-size: 18px;
    cursor: pointer;
}

.navbar {
    position: absolute;
    top: 10px;
    left: 10px;
}


.hamburger {
    font-size: 28px;
    cursor: pointer;
    user-select: none;
}

/* Menu (hidden by default) */
.menu {
    display: none;
    margin-top: 10px;
    background: white;
    padding: 10px;
    border-radius: 8px;
}


.menu a {
    text-decoration: none;
    color: black;
    font-weight: bold;
}

/* Show menu */
.menu.show {
    display: block;
}