Isotop/Portfolio | CSS Code

#portfolio {
  padding: 100px 0;
  background: #f5f5f5;
}
#portfolio .portfolio-filter {
  list-style: none;
  padding: 0;
  margin: 0 0 50px;
  display: inline-block;
}
#portfolio .portfolio-filter > li {
  float: left;
  display: block;
}
#portfolio .portfolio-filter > li a {
  display: block;
  padding: 7px 15px;
  background: #e5e5e5;
  color: #64686d;
  position: relative;
}
#portfolio .portfolio-filter > li a:hover,
#portfolio .portfolio-filter > li a.active {
  background: #45aed6;
  color: #fff;
  box-shadow: 0 -3px 0 0 #318daf inset;
  -webkit-box-shadow: 0 -3px 0 0 #318daf inset;
}
#portfolio .portfolio-filter > li a.active:after {
  content: " ";
  position: absolute;
  bottom: -17px;
  left: 50%;
  margin-left: -10px;
  border-width: 10px;
  border-style: solid;
  border-color: #318daf transparent transparent transparent;
}
#portfolio .portfolio-filter > li:first-child a {
  border-radius: 4px 0 0 4px;
}
#portfolio .portfolio-filter > li:last-child a {
  border-radius: 0 4px 4px 0;
}
#portfolio .portfolio-items {
  margin: -15px;
}
#portfolio .portfolio-item {
  width: 24.9%;
  float: left;
  padding: 15px;
  -webkit-box-sizing: border-box;
  -moz-box-sizing: border-box;
  -o-box-sizing: border-box;
  -ms-box-sizing: border-box;
  box-sizing: border-box;
}
#portfolio .portfolio-item .portfolio-item-inner {
  position: relative;
}
#portfolio .portfolio-item .portfolio-item-inner .portfolio-info {
  opacity: 0;
  transition: opacity 400ms;
  -webkit-transition: opacity 400ms;
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 10px;
  background: rgba(0, 0, 0, 0.5);
  color: #fff;
}
#portfolio .portfolio-item .portfolio-item-inner .portfolio-info h3 {
  font-size: 16px;
  line-height: 1;
  margin: 0;
  color: #fff;
}
#portfolio .portfolio-item .portfolio-item-inner .portfolio-info .preview {
  position: absolute;
  top: -18px;
  right: 12px;
  border-radius: 50%;
  background-image: -moz-linear-gradient(90deg, #2caab3 0%, #2c8cb3 100%);
  background-image: -webkit-linear-gradient(90deg, #2caab3 0%, #2c8cb3 100%);
  background-image: -ms-linear-gradient(90deg, #2caab3 0%, #2c8cb3 100%);
  width: 36px;
  height: 36px;
  line-height: 36px;
  text-align: center;
  color: #fff;
  box-shadow: 0 0 0 2px #fff;
  -webkit-box-shadow: 0 0 0 2px #fff;
}
#portfolio .portfolio-item:hover .portfolio-info {
  opacity: 1;
}
/* Start: Recommended Isotope styles */
/**** Isotope Filtering ****/
.isotope-item {
  z-index: 2;
}
.isotope-hidden.isotope-item {
  pointer-events: none;
  z-index: 1;
}
/**** Isotope CSS3 transitions ****/
.isotope,
.isotope .isotope-item {
  -webkit-transition-duration: 0.8s;
  -moz-transition-duration: 0.8s;
  -ms-transition-duration: 0.8s;
  -o-transition-duration: 0.8s;
  transition-duration: 0.8s;
}
.isotope {
  -webkit-transition-property: height, width;
  -moz-transition-property: height, width;
  -ms-transition-property: height, width;
  -o-transition-property: height, width;
  transition-property: height, width;
}
.isotope .isotope-item {
  -webkit-transition-property: -webkit-transform, opacity;
  -moz-transition-property: -moz-transform, opacity;
  -ms-transition-property: -ms-transform, opacity;
  -o-transition-property: -o-transform, opacity;
  transition-property: transform, opacity;
}
/**** disabling Isotope CSS3 transitions ****/
.isotope.no-transition,
.isotope.no-transition .isotope-item,
.isotope .isotope-item.no-transition {
  -webkit-transition-duration: 0s;
  -moz-transition-duration: 0s;
  -ms-transition-duration: 0s;
  -o-transition-duration: 0s;
  transition-duration: 0s;
}
/* End: Recommended Isotope styles */
/* disable CSS transitions for containers with infinite scrolling*/
.isotope.infinite-scrolling {
  -webkit-transition: none;
  -moz-transition: none;
  -ms-transition: none;
  -o-transition: none;
  transition: none;
}