style.css

@import url('https://fonts.googleapis.com/css2?family=Dosis:wght@200;300;400;500;600&display=swap');
:root{
    --left-bg-color: rgba(99, 99, 198, 0.6);
    --right-bg-color: rgba(43, 43, 43, 0.8);
    --left-btn-hover-color: rgba(77, 77, 178, 1);
    --right-btn-hover-color: rgba(28, 123, 28, 1);
    --hover-width: 70%;
    --other-width: 30%;
    
}
*{
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Dosis', sans-serif;
    
    height: 100vh;
}

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

.split {
    position: absolute;
    color: #fff;
    width: 50%;
    height: 100%;
    overflow: hidden;
}
.split.left {
    background: url(/playstation5.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    left: 0;
}
.split.left::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: var(--left-bg-color);
}
.split.right {
    background: url(/xbox\ x.jpg);
    background-repeat: no-repeat;
    background-size: cover;
    right: 0;
}
.split.right::before {
    content: '';
    position: absolute;
    width: 100%;
    height: 100%;
    background: var(--right-bg-color);
}

.split.left, .split.left::before, .split.right, .split.right::before {
    transition: all 0.4s ease-in-out  0.255ms;
}

h1 {
    position: absolute;
    top: 30%;
    left: 50%;
    transform: translateX(-50%);
    font-size: clamp(1.5rem, 5vw, 5rem);
    white-space: nowrap;
}

.btn {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translateX(-50%);
    border: 1px solid #fff;
    text-decoration: none;
    font-size: 1em;
    padding: 1.5rem;
    width: 15rem;
    color: #fff;
    text-align: center;
    text-transform: uppercase;
    transition: 0.4s;
}

.split.left .btn:hover {
    background: var(--left-btn-hover-color);
    border-color: var(--left-btn-hover-color);
}
.split.right .btn:hover {
    background: var(--right-btn-hover-color);
    border-color: var(--right-btn-hover-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:729px) {
    .btn {
        font-size: 1em;
        padding: 1rem;
        width: 8rem;
        top: 45%;
    }
}