* {
    margin: 0;
    padding: 0;
}

body {
    background: #323F4A;
    display: grid;
    place-items: center;
    min-height: 100vh;
}

.button {
    width: 100px;
    background: #1B1C19;
    padding-inline: 18px;
    padding-block: 12px;
    display: grid;
    place-items: center;
    position: relative;
    cursor: pointer;
}

.button span {
    color: #FEE333;
    font-size: 1.2rem;
}

.button .yellow-transition {
    height: 100%;
    width: 0;
    background: #FEE333;
    position: absolute;
    left: 0;
    transition: width .3s ease, transform .3s;
}

.button:hover {
    transform: translateY(-2px);
}

.button::after{
    content: "";
    position: absolute;
    top: 100%;
    width: 100%;
    height: 10px;
}

.button:hover .yellow-transition {
    width: 100%;
}

.button:hover span {
    color: #1B1C19;
    z-index: 1;
    font-weight: 900;
}