ul.menu-center  li.active a {
    color: #668846;
}
<!-- ------------------------------------- style for content-------------------------------------------- -->
 ul.menu-center  li.active a {
    font-size: 19px;
    color: #668846;
}
 

.design-item-container:after {
    clear: both;
}

.design-item-container .design-item-left, .design-item-container .design-item-right {
    position: relative;
    top: 50%;
    transform: translateY(-50%);
    float:left;
    
    
}
.design-container {
    float: left;
    height: inherit;
    -webkit-perspective: 1000px;
    -moz-perspective: 1000px;
    perspective: 1000px;
    width: 616px;
}


.design-left-container {
     transform:rotateY(30deg);
     height: inherit;
     width: 711px;
    
}

.design-right-container {
    transform:rotateY(-30deg);
     height: inherit;
     width: 711px;
    margin-left: -50px;
}

.design-item-left .border, .design-item-right .border {
   
    clear: both;
}

.design-item-container img {
    width: inherit;
    height: inherit;
}

.design-item-container .border {
   
    margin: 8px 0px 0px 8px;
}

.design-item-container .border img {
     border: 2px solid #FFF;
}

.design-item-container  .lv1 {
    width: 250px;
    height: 334px; 
}

.design-item-container  .lv2 {
    width: 225px;
    height: 310px;
}

.design-item-container  .lv3 {
    width: 200px;
    height: 300px;
}

.design-item-container {
    display: block;
    margin-left: auto;
    margin-right: auto;
    height: 900px;
    margin-top: 100px;
    width: 1235px;
}

@media only screen and (min-width: 1024px){
    
    .design-container {
       width: 237px;
    }


    .design-left-container {
        width: 270px;
    }

    .design-right-container {
        width: 270px;
        margin-left: -20px;
    }

    .design-item-container  .lv1 {
        width:  84px;
        height: 117px;
    }

    .design-item-container  .lv2 {
        width:  84px;
        height: 117px;
    }

    .design-item-container  .lv3 {
        width:  84px;
        height: 117px;
    }

    .design-item-container {
        height: 351px;
        margin-top: 64px;
        width: 474px;
    }
    
    .design-item-container .border {
        margin: 4px 0px 0px 4px;
    }
}
@media only screen and (min-width: 1600px){
    
    .design-container {
       width: 312px;
    }


    .design-left-container {
        width: 356px;
    }

    .design-right-container {
        width: 356px;
        margin-left: -30px;
    }

    .design-item-container  .lv1 {
        width:  112px;
        height: 151px;
    }

    .design-item-container  .lv2 {
        width:  112px;
        height: 151px;
    }

    .design-item-container  .lv3 {
        width:  112px;
        height: 151px;
    }

    .design-item-container {
        height: 453px;
        margin-top: 82px;
        width: 624px;
    }
}

@media only screen and (min-width: 1920px){
    
    .design-container {
       width: 383px;
    }


    .design-left-container {
        width: 435px;
    }

    .design-right-container {
         width: 435px;
        margin-left: -50px;
    }

    .design-item-container  .lv1 {
        width:  137px;
        height: 184px;
    }

    .design-item-container  .lv2 {
        width:  137px;
        height: 184px;
    }

    .design-item-container  .lv3 {
        width:  137px;
        height: 184px;
    }

    .design-item-container {
        height: 552px;
        margin-top: 100px;
        width: 766px;
    }
}

@media only screen and (min-width: 2560px){
    
    .design-container {
       width: 516px;
    }


    .design-left-container {
        width: 583px;
    }

    .design-right-container {
        width: 583px;
        margin-left: -80px;
    }

    .design-item-container  .lv1 {
        width:  189px;
        height: 255px; 
    }

    .design-item-container  .lv2 {
        width:  189px;
        height: 255px; 
    }

    .design-item-container  .lv3 {
        width:  189px;
        height: 255px; 
    }

    .design-item-container {
        height: 765px;
        margin-top: 139px;
        width: 1032px;
    }
}



/* CSS Hover Image */
.ch-img-item {
    width: 100%;
    height: 100%;
    position: relative;
    cursor: default;
}

.ch-img-info-wrap{
    position: absolute;
    width: 180px;
    height: 180px;
    border-radius: 50%;

    -webkit-perspective: 800px;
    -moz-perspective: 800px;
    -o-perspective: 800px;
    -ms-perspective: 800px;
    perspective: 800px;

    -webkit-transition: all 0.4s ease-in-out;
    -moz-transition: all 0.4s ease-in-out;
    -o-transition: all 0.4s ease-in-out;
    -ms-transition: all 0.4s ease-in-out;
    transition: all 0.4s ease-in-out;

    top: 20px;
    left: 20px;

}

.ch-img-info{
    position: absolute;
    width: 100%;
    height: 100%;
    -webkit-transition: all 0.4s ease-in-out;
    -moz-transition: all 0.4s ease-in-out;
    -o-transition: all 0.4s ease-in-out;
    -ms-transition: all 0.4s ease-in-out;
    transition: all 0.4s ease-in-out;
        
    -webkit-transform-style: preserve-3d;
    -moz-transform-style: preserve-3d;
    -o-transform-style: preserve-3d;
    -ms-transform-style: preserve-3d;
    transform-style: preserve-3d;

}

.ch-img-info > div {
    display: block;
    position: absolute;
    width: 100%;
    height: 100%;
    background-position: center center;

    -webkit-backface-visibility: hidden;
    -moz-backface-visibility: hidden;
    -o-backface-visibility: hidden;
    -ms-backface-visibility: hidden;
    backface-visibility: hidden;
}

.ch-img-info .ch-img-info-back {
    -webkit-transform: rotate3d(0,1,0,180deg);
    -moz-transform: rotate3d(0,1,0,180deg);
    -o-transform: rotate3d(0,1,0,180deg);
    -ms-transform: rotate3d(0,1,0,180deg);
    transform: rotate3d(0,1,0,180deg);
}

.ch-img-item:hover .ch-img-info-wrap {
    box-shadow: 
        0 0 0 0 rgba(255,255,255,0.8), 
        inset 0 0 3px rgba(115,114, 23, 0.8);
}

.ch-img-item:hover .ch-img-info {
    -webkit-transform: rotate3d(0,1,0,-180deg);
    -moz-transform: rotate3d(0,1,0,-180deg);
    -o-transform: rotate3d(0,1,0,-180deg);
    -ms-transform: rotate3d(0,1,0,-180deg);
    transform: rotate3d(0,1,0,-180deg);
}