.abc {
    position: relative;
    padding: 10px 30px;
    margin: 0 45px;
    color: #3198f3;
    text-decoration: none;
    font-size: 20px;
    text-transform: uppercase;
    transition: 0.5s;
    overflow: hidden;
    -webkit-box-reflect: below 1px linear-gradient(transparent, #0003);
}

.abc:hover {
    background: #3198f3;
    color: #111;
    box-shadow: 0 0 50px #3198f3;
    transition-delay: 0.5s;
}

.abc:nth-child(1) {
    filter: hue-rotate(115deg);
}


.abc::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 10px;
    height: 10px;
    border-top: 2px solid #3198f3;
    border-left: 2px solid #3198f3;
    transition: 0.5s;
    transition-delay: 0.5s;
}

.abc:hover::before {
    width: 100%;
    height: 100%;
    transition-delay: 0s;
}

.abc::after {
    content: '';
    position: absolute;
    right: 0;
    bottom: 0;
    width: 10px;
    height: 10px;
    border-bottom: 2px solid #3198f3;
    border-right: 2px solid #3198f3;
    transition: 0.5s;
    transition-delay: 0.5s;
}

.abc:hover::after {
    width: 100%;
    height: 100%;
    transition-delay: 0s;
}