.zt-title{
    position: relative;
}
.zt-title.zt-title-single-bottom {
    border-bottom: 1px solid #d4d4d4;
}
.zt-title.zt-title-double-bottom{
    border-bottom: 4px double #d4d4d4;
}
.zt-title.zt-title-single-border:before,
.zt-title.zt-title-double-border:before,
.zt-title.zt-title-double-border:after{
    position: absolute;
    content: "";
    width: 100%;
    z-index: 0;
    height: 1px;
    background-color: #d4d4d4;
    left: 0;
}
.zt-title.zt-title-single-border .zt-title-heading,
.zt-title.zt-title-double-border .zt-title-heading{
    background-color: #fff;
    display: inline-block;
    padding-right: 20px;
    position: relative;
    z-index: 9;
    margin: 0;
}
.zt-title.zt-title-single-border:before{
    top: 50%;
}
.zt-title.zt-title-double-border:before{
    top: calc(50% - 2px);
}
.zt-title.zt-title-double-border:after{
    top: calc(50% + 1px);
}