.t-underline {
    position: relative;
    
    display: inline-block;
    
    transition: color 0.3s ease;
}
.t-underline::before {
    position: absolute;
    
    width: 0%;
    height: 2px;
    bottom: -1px;
    left: 50%;

    content: "";
    background-color: rgb(255, 0, 0);
    
    transition: width 0.3s ease, left 0.3s ease;
}
.t-underline:hover::before {
    width: 100%;
    left: 0;
}
.button-1 {
    border: none;
    background: none;

    margin-bottom: 0.5em;
    padding: 0.4em 2em;
    box-shadow: 0 0 0 1.2em rgb(60, 60, 60) inset;
    
    transition: 0.3s;
    color: white;
    cursor: pointer;
}
.button-1:hover {
    box-shadow: 0 0 0 0.15em rgb(60, 60, 60) inset;
    color: rgb(255, 0, 0);
}