.btn {
    position: relative;
    border-radius: 7px;
    font-size: 20px;
    text-transform: uppercase;
    font-weight: 900;
    font-family: 'Montserrat', Arial, sans-serif;
    background: transparent;
    color: #bbbbbb;
    overflow: hidden;
    -webkit-transition: all 0.2s ease-in;
    -moz-transition: all 0.2s ease-in;
    transition: all 0.2s ease-in;
    box-shadow: inset 0 0 15px rgba(255,15,50,1), 0 0 10px rgba(255,15,50,1);
    backdrop-filter: blur(30px);
}

.btn:hover {
    color: white;
       background: transparent;
    transform: scale(1.05);
    box-shadow: inset 0 0 30px rgba(255,15,50,1), 0 0 10px rgba(255,15,50,1);;
    -webkit-transition: all 0.2s ease-out;
    -moz-transition: all 0.2s ease-out;
    transition: all 0.2s ease-out;
}

.btn:hover::before {
    -webkit-animation: sh02 0.5s 0s linear;
    -moz-animation: sh02 0.5s 0s linear;
    animation: sh02 0.5s 0s linear;
}

.btn::before {
    content: '';
    display: block;
    width: 0px;
    height: 86%;
    position: absolute;
    top: 7%;
    left: 0%;
    opacity: 0;
    background: #fff;
    box-shadow: 0 0 50px 30px #fff;
    -webkit-transform: skewX(-20deg);
    -moz-transform: skewX(-20deg);
    -ms-transform: skewX(-20deg);
    -o-transform: skewX(-20deg);
    transform: skewX(-20deg);
}

@keyframes sh02 {
    from {
        opacity: 0;
        left: 0%;
    }

    50% {
        opacity: 1;
    }

    to {
        opacity: 0;
        left: 100%;
    }
}

.btn:active {
    box-shadow: 0 0 0 0 transparent;
    -webkit-transition: box-shadow 0.2s ease-in;
    -moz-transition: box-shadow 0.2s ease-in;
    transition: box-shadow 0.2s ease-in;
}