<a href="tel: 8 888 888 88 88" rel="nofollow" class="btn-call">
      <div class="btn-call__ico">
        <i class="fas fa-phone-alt"></i>
      </div>
    </a>

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  background-color: #ccc;
}

/* btn-call */

.btn-call {
    background: #38a3fd;
    border: 2px solid #38a3fd;
    border-radius: 50%;
    box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3);
    cursor: pointer;
    height: 60px;
    width: 60px;
    text-align: center;
    position: fixed;
    right: 50px;
    bottom: 50px;
    z-index: 999;
    transition: .3s;
    -webkit-animation: hoverWave linear 1s infinite;
    animation: hoverWave linear 1s infinite;
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
}

.btn-call__ico {
    display: flex;
    justify-content: center;
    align-items: center;
    animation: 1200ms ease 0s normal none 1 running shake;
    animation-iteration-count: infinite;
    -webkit-animation: 1200ms ease 0s normal none 1 running shake;
    -webkit-animation-iteration-count: infinite;
    color: white;
    font-size: 30px;
    padding-top: 5px;
    transition: .3s all;
}

.btn-call:hover {
    background-color: #fff;
}

.btn-call:hover .btn-call__ico {
    color: #38a3fd;
}

@-webkit-keyframes hoverWave {
    0% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 0 rgba(56, 163, 253, 0.2), 0 0 0 0 rgba(56, 163, 253, 0.2)
    }

    40% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 15px rgba(56, 163, 253, 0.2), 0 0 0 0 rgba(56, 163, 253, 0.2)
    }

    80% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 30px rgba(56, 163, 253, 0), 0 0 0 26.7px rgba(56, 163, 253, 0.067)
    }

    100% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 30px rgba(56, 163, 253, 0), 0 0 0 40px rgba(56, 163, 253, 0.0)
    }
}

@keyframes hoverWave {
    0% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 0 rgba(56, 163, 253, 0.2), 0 0 0 0 rgba(56, 163, 253, 0.2)
    }

    40% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 15px rgba(56, 163, 253, 0.2), 0 0 0 0 rgba(56, 163, 253, 0.2)
    }

    80% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 30px rgba(56, 163, 253, 0), 0 0 0 26.7px rgba(56, 163, 253, 0.067)
    }

    100% {
        box-shadow: 0 8px 10px rgba(56, 163, 253, 0.3), 0 0 0 30px rgba(56, 163, 253, 0), 0 0 0 40px rgba(56, 163, 253, 0.0)
    }
}

/* animations icon */

@keyframes shake {
    0% {
        transform: rotateZ(0deg);
        -ms-transform: rotateZ(0deg);
        -webkit-transform: rotateZ(0deg);
    }

    10% {
        transform: rotateZ(-30deg);
        -ms-transform: rotateZ(-30deg);
        -webkit-transform: rotateZ(-30deg);
    }

    20% {
        transform: rotateZ(15deg);
        -ms-transform: rotateZ(15deg);
        -webkit-transform: rotateZ(15deg);
    }

    30% {
        transform: rotateZ(-10deg);
        -ms-transform: rotateZ(-10deg);
        -webkit-transform: rotateZ(-10deg);
    }

    40% {
        transform: rotateZ(7.5deg);
        -ms-transform: rotateZ(7.5deg);
        -webkit-transform: rotateZ(7.5deg);
    }

    50% {
        transform: rotateZ(-6deg);
        -ms-transform: rotateZ(-6deg);
        -webkit-transform: rotateZ(-6deg);
    }

    60% {
        transform: rotateZ(5deg);
        -ms-transform: rotateZ(5deg);
        -webkit-transform: rotateZ(5deg);
    }

    70% {
        transform: rotateZ(-4.28571deg);
        -ms-transform: rotateZ(-4.28571deg);
        -webkit-transform: rotateZ(-4.28571deg);
    }

    80% {
        transform: rotateZ(3.75deg);
        -ms-transform: rotateZ(3.75deg);
        -webkit-transform: rotateZ(3.75deg);
    }

    90% {
        transform: rotateZ(-3.33333deg);
        -ms-transform: rotateZ(-3.33333deg);
        -webkit-transform: rotateZ(-3.33333deg);
    }

    100% {
        transform: rotateZ(0deg);
        -ms-transform: rotateZ(0deg);
        -webkit-transform: rotateZ(0deg);
    }
}

@-webkit-keyframes shake {
    0% {
        transform: rotateZ(0deg);
        -ms-transform: rotateZ(0deg);
        -webkit-transform: rotateZ(0deg);
    }

    10% {
        transform: rotateZ(-30deg);
        -ms-transform: rotateZ(-30deg);
        -webkit-transform: rotateZ(-30deg);
    }

    20% {
        transform: rotateZ(15deg);
        -ms-transform: rotateZ(15deg);
        -webkit-transform: rotateZ(15deg);
    }

    30% {
        transform: rotateZ(-10deg);
        -ms-transform: rotateZ(-10deg);
        -webkit-transform: rotateZ(-10deg);
    }

    40% {
        transform: rotateZ(7.5deg);
        -ms-transform: rotateZ(7.5deg);
        -webkit-transform: rotateZ(7.5deg);
    }

    50% {
        transform: rotateZ(-6deg);
        -ms-transform: rotateZ(-6deg);
        -webkit-transform: rotateZ(-6deg);
    }

    60% {
        transform: rotateZ(5deg);
        -ms-transform: rotateZ(5deg);
        -webkit-transform: rotateZ(5deg);
    }

    70% {
        transform: rotateZ(-4.28571deg);
        -ms-transform: rotateZ(-4.28571deg);
        -webkit-transform: rotateZ(-4.28571deg);
    }

    80% {
        transform: rotateZ(3.75deg);
        -ms-transform: rotateZ(3.75deg);
        -webkit-transform: rotateZ(3.75deg);
    }

    90% {
        transform: rotateZ(-3.33333deg);
        -ms-transform: rotateZ(-3.33333deg);
        -webkit-transform: rotateZ(-3.33333deg);
    }

    100% {
        transform: rotateZ(0deg);
        -ms-transform: rotateZ(0deg);
        -webkit-transform: rotateZ(0deg);
    }
}