.play-btn {
    width: 100px;
    height: 100px;
    background: radial-gradient( rgba(5, 24, 24, 0.8) 60%, rgba(30, 135, 240, 1) 62%);
    border-radius: 50%;
    position: relative;
    display: block;
    margin: 10% 16px 8% auto;
    box-shadow: 0px 0px 25px 3px rgba(30, 135, 239, 0.68);
}
@media (max-width: 474px) {
    .play-btn{
        margin: 2% auto;
        margin-top: 30px;
        margin-bottom: 30px;
    }
    .zero-margin-MAX-474{
        margin: 0 0 0 0 !important;
    }
}

/* triangle */
.play-btn::after {
    content: "";
    position: absolute;
    left: 50%;
    top: 50%;
    -webkit-transform: translateX(-40%) translateY(-50%);
    transform: translateX(-40%) translateY(-50%);
    transform-origin: center center;
    width: 0;
    height: 0;
    border-top: 15px solid transparent;
    border-bottom: 15px solid transparent;
    border-left: 25px solid #fff;
    z-index: 100;
    -webkit-transition: all 400ms cubic-bezier(0.55, 0.055, 0.675, 0.19);
    transition: all 400ms cubic-bezier(0.55, 0.055, 0.675, 0.19);
}

/* pulse wave */
.play-btn:before {
    content: "";
    position: absolute;
    width: 150%;
    height: 150%;
    -webkit-animation-delay: 0s;
    animation-delay: 0s;
    -webkit-animation: pulsate1 2s;
    animation: pulsate1 2s;
    -webkit-animation-direction: forwards;
    animation-direction: forwards;
    -webkit-animation-iteration-count: infinite;
    animation-iteration-count: infinite;
    -webkit-animation-timing-function: steps;
    animation-timing-function: steps;
    opacity: 1;
    border-radius: 50%;
    border: 3px solid rgba(30, 135, 240, .75);
    top: -25.5%;
    left: -25.5%;
    background: rgba(198, 16, 0, 0);
}

@-webkit-keyframes pulsate1 {
    0% {
        -webkit-transform: scale(0.6);
        transform: scale(0.6);
        opacity: 1;
        box-shadow: inset 0px 0px 25px 3px rgba(30, 135, 240, .75), 0px 0px 25px 10px rgba(30, 135, 240, .75);
    }
    100% {
        -webkit-transform: scale(1);
        transform: scale(1);
        opacity: 0;
        box-shadow: none;

    }
}

@keyframes pulsate1 {
    0% {
        -webkit-transform: scale(0.6);
        transform: scale(0.6);
        opacity: 1;
        box-shadow: inset 0px 0px 25px 3px rgba(30, 135, 240, .75), 0px 0px 25px 10px rgba(30, 135, 240, .75);
    }
    100% {
        -webkit-transform: scale(1, 1);
        transform: scale(1);
        opacity: 0;
        box-shadow: none;

    }
}