Please add this to Theme Options => Custom CSS:
.woocommerce div.product .woocommerce-tabs ul.tabs {
float: none;
width: 100%;
font-size: 12px;
font-weight: normal;
margin-left: 0;
padding-left: 0;
overflow: visible;
}
.woocommerce div.product .woocommerce-tabs ul.tabs li {
background: transparent !important;
margin: 0 !important;
box-shadow: none;
padding: 0 !important;
-webkit-border-radius: 0;
-moz-border-radius: 0;
border-radius: 0;
border: 0;
width: auto;
display: inline-block;
}
.woocommerce div.product .woocommerce-tabs ul.tabs li a {
white-space: nowrap;
margin-right: 0;
padding: 9px 10px;
display: block;
background: transparent;
text-overflow: none !important;
overflow: auto;
max-width: none !important;
font-size: 12px !important;
text-transform: uppercase;
letter-spacing: 0px;
}
.woocommerce div.product .woocommerce-tabs ul.tabs li.active a {
background: #eee;
}
.woocommerce div.product .woocommerce-tabs ul.tabs li.active a:after {
display:none;
}
.woocommerce div.product .woocommerce-tabs {
margin-top:10px;
}