button {
        position: relative;
        display: inline-block;
        cursor: pointer;
        outline: none;
        border: 0;
        vertical-align: middle;
        text-decoration: none;
        background: transparent;
        padding: 0;
        font-size: inherit;
        font-family: inherit;
}

button.btnA {
        width: 210px;
        height: auto;
}

button.btnA .circle {
        position: relative;
        display: block;
        margin: 0;
        width: 40px;
        height: 40px;
        background: #101010;
        border-radius: 26px;
        transition: all 0.45s cubic-bezier(0.65, 0, 0.076, 1);
}

button.btnA .icon {
        transition: all 0.45s cubic-bezier(0.65, 0, 0.076, 1);
        position: absolute;
        top: 0;
        bottom: 0;
        margin: auto;
}

button.btnA .icon.arrow {
        left: 6px; width: 18px; height: 2px;
        transition: all 0.45s cubic-bezier(0.65, 0, 0.076, 1);        
}

button.btnA .icon.arrow::before {
        position: absolute;
        content: "";
        top: -5px;
        right: 1px;
        width: 10px;
        height: 10px;
        border-top: 2px solid #fff;
        border-right: 2px solid #fff;
        transform: rotate(45deg);
}

button.btnA .button-text {
        transition: all 0.45s cubic-bezier(0.65, 0, 0.076, 1);
        position: absolute;
        top: 0; left: 0;
        right: 0; bottom: 0;
        padding: 8px 0;
        margin: 0 0 0 35px;
        font-weight: 400;
        line-height: 1.6;
        text-align: center;
        opacity: 0;
}

button:hover .circle {width: 100%}

button:hover .button-text {
        color: #fff; opacity: 1;
}