styles.css

*{
    box-sizing: border-box;
}
:root{
    --left--bg-color:rgba(32, 31, 59, 0.7);
    --right--bg-color:rgba(43,43,43,0.8);
    --left-btn-hover-color: rgba(242, 7, 7, 0.598);
    --right-btn-hover-color: rgba(4, 5, 4, 0.419);
    --hover-width: 75%;
    --other-width: 25%;
    --speed: 1000ms;

}

body{
    font-family: 'Roboto', sans-serif;
    height: 100vh;
    overflow: hidden;
    margin: 0;
}
h1{
    font-size: 4rem;
    color: #fff;
    position: absolute;
    left: 50%;
    top: 20%;
    transform: translateX(-50%);
    white-space: nowrap;
}

.btn{
    position: absolute;
    display: flex;
    align-items: center;
    justify-content: center;
    left: 50%;
    top: 40%;
    transform: translateX(-50%);
    text-decoration: none;
    color: #fff;
    border: #fff solid 0.2rem;
    font-size: 1rem;
    font-weight: bold;
    text-transform: uppercase;
    width: 15rem;
    padding: 1.5rem;
    border-radius: 11px;
}
.split.left .btn:hover{
    background-color: var(--left-btn-hover-color);
    border-color: var(--left-btn-hover-color);
}

.split.right .btn:hover{
    background-color: var(--right-btn-hover-color);
    border-color: var(--right-btn-hover-color);
}

.split.right,.split.left,.split.right::before,.split.left::before{
transition: all var(--speed)ease-in-out;
} 

.container{
    position: relative;
    width: 100%;
    height: 100%;
    background-color: #333;
}


.split{
    position: absolute;
    width: 50%;
    height: 100%;
    overflow: hidden;

}

.split.left{
    left: 0;
    background: url(./images/2013-tesla-model-s-reviews-car-and-driver-photo-461958-s-original.jpg);
    background-repeat: no-repeat;
    background-size: cover;
}

.split.left::before{
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background-color:var(--left--bg-color) ;
}

.split.right{
    right: 0;
    background: url(./images/pexels-mike-b-205740.jpg);
    background-repeat: no-repeat;
    background-size: cover;

}

.split.right::before{
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background-color:var(--right--bg-color) ;
}

.hover-left .left{
    width: var(--hover-width);
}

.hover-left .right{
    width: var(--other-width);
}


.hover-right .right{
    width: var(--hover-width);
}

.hover-right .left{
    width: var(--other-width);
}

@media(max-width:800px){
    h1{
        font-size: 2rem;
        top: 30%;
    }

    .btn{   padding: 1.2rem;
            width: 12rem;;
    }
}

footer{
    color: #fff;
}