* {
    margin: 0;
    padding: 0;

    &,
    &::before,
    &::after {
        box-sizing: border-box;
    }
}

html {
    font-family: Verdana, Geneva, Tahoma, sans-serif;
    line-height: 1.2;
    color: $color-white;
    height: 100%;
    overflow: hidden;
}

body {
    display: flex;
    background: linear-gradient(159deg, #311 0%, #b83939 40%, #441515 80%);
    overflow: hidden;
    width: 100%;
    height: 100%;
    font-size: 16px;

    &:before {
        content: "";
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 470px;
        background: linear-gradient(180deg, #111 0%, transparent 57%);
        z-index: 2;
    }
}

button {
    display: block;
    padding: 16px;
    margin: 24px auto 0;
    width: 100%;
    max-width: 400px;
    border: none;
    background-color: $color-green-dark;
    color: $color-white;
    font-weight: 700;
    font-size: 24px;
    box-shadow: 4px 4px 0 rgba(0, 0, 0, 0.5);
    border-radius: 10px;
    cursor: pointer;
    transition: all 250ms ease;

    &:hover {
        background: #6db58a;
    }
}

#help {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    margin: 0;
    z-index: 9;

    ul {
        margin-top: 12px;
    }

    li {
        text-align: left;
        margin: 8px 0;
    }

    &:not(.-active) {
        display: none;
    }
}

#helpClose {
    position: absolute;
    top: 0;
    right: 0;
    padding: 8px;
    font-size: 20px;
    font-weight: 700;
    cursor: pointer;
}

#helpButton,
#soundButton {
    position: fixed;
    bottom: 10px;
    right: 10px;
    padding: 8px;
    font-size: 30px;
    cursor: pointer;
    z-index: 8;

    @media (min-width: 768px) {
        font-size: 42px;
    }
}

#helpButton {
    &:not(.-active) {
        display: none;
    }

    &.-blink {
        animation: blink 1s infinite;
    }

    right: 60px;

    @media (min-width: 768px) {
        right: 80px;
    }
}

@keyframes blink {
    50% {
        opacity: 0;
    }
}
