.wa-icon {
    width: 30px;
    height: 30px;
    fill: white;
}            
            
/* Variant 19: Minimal Line */
.btn-19 {
    width: 60px;
    height: 60px;
    background: transparent;
    border: 2px solid #25d366;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s;
    position: relative;
}
.btn-19::before {
    content: "";
    position: absolute;
    width: 0;
    height: 0;
    background: #25d366;
    border-radius: 50%;
    transition: all 0.3s;
    z-index: -1;
}
.btn-19:hover::before {
    width: 100%;
    height: 100%;
}
.btn-19 svg {
    fill: #25d366;
    transition: fill 0.3s;
    position: relative;
    z-index: 1;
}
.btn-19:hover svg {
    fill: white;
}