body {
    background-color: #0093E9;
    background-image: linear-gradient(157deg, #0093E9 0%, #80D0C7 100%);
    min-height: 100vh;
    height: 100%;
    padding: 4rem 0;
}

.player-container {
    background: rgba( 240, 240, 240, 0.9 );
    box-shadow: 0 8px 32px 0 rgba( 31, 38, 135, 0.37 );
    backdrop-filter: blur( 4.5px );
    -webkit-backdrop-filter: blur( 4.5px );
    border-radius: 10px;
    border: 1px solid rgba( 255, 255, 255, 0.18 );
}

.chapter {
    cursor: pointer;
    color: #1E90FF;
}

.chapter.playing h4 {
    font-weight: 700;
    color: #f19c00;
}

.play-controls .active {
    cursor: pointer;
    color: #1E90FF;
}

.playlist-container {
    max-height: 500px;
    overflow-y: auto;
}

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

@keyframes rotate {
    100% {
        transform: rotate(1turn);
    }
}

.loading-container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 80vh;
}

.rainbow {
    position: relative;
    z-index: 0;
    width: 400px;
    height: 300px;
    border-radius: 10px;
    overflow: hidden;
    padding: 2rem;

    &::before {
        content: '';
        position: absolute;
        z-index: -2;
        left: -50%;
        top: -50%;
        width: 200%;
        height: 200%;
        background-color: #399953;
        background-repeat: no-repeat;
        background-size: 50% 50%, 50% 50%;
        background-position: 0 0, 100% 0, 100% 100%, 0 100%;
        background-image: linear-gradient(#399953, #399953), linear-gradient(#fbb300, #fbb300), linear-gradient(#d53e33, #d53e33), linear-gradient(#377af5, #377af5);
        animation: rotate 4s linear infinite;
    }

    &::after {
        content: '';
        position: absolute;
        z-index: -1;
        left: 6px;
        top: 6px;
        width: calc(100% - 12px);
        height: calc(100% - 12px);
        background: white;
        border-radius: 5px;
        animation: opacityChange 3s infinite alternate;
    }
}

@keyframes opacityChange {
    50% {
        opacity: 1;
    }

    100% {
        opacity: .5;
    }
}