.wrap {
  margin: 0 auto;
  max-width: 1400px;
  width: 100%;
  display: flex;
  justify-content: center;
}

h1 {
  text-align: center;
  margin: 50px 0;
}

.gallery-wrap,
#gallery {
  overflow: hidden;
}

#filters {
  list-style: none;
}

#filters li span {
  text-decoration: none;
  color: #666;
  border: 1px solid #000;
  cursor: pointer;
  text-transform: uppercase;
  transition: all ease-in-out 0.25s;
}

#filters li:hover span {
  color: #000;
}

#filters li span.active {
  background: #000;
  color: #fff;
}

.gallery-item {
  float: left;
  width: 25%;
  padding: 10px;
  position: relative;
  z-index: 10;
  display: none;
  left: 0;
  right: 0;
}

.gallery-item2 {
  float: left;
  width: 30%;
  padding: 10px;
  position: relative;
  z-index: 10;
  display: none;
  left: 0;
  right: 0;
}


.inside {
  position: relative;
  overflow: hidden;
  width: 100%;
  height: 100%;
}

.inside img {
  float: none;
  width: 100%;
}

.inside img {
  transition: filter .5s ease-in-out;
  -webkit-filter: grayscale(0%); /* Ch 23+, Saf 6.0+, BB 10.0+ */
  filter: grayscale(0%); /* FF 35+ */
}

.inside img:hover {
  -webkit-filter: grayscale(100%); /* Ch 23+, Saf 6.0+, BB 10.0+ */
  filter: grayscale(100%); /* FF 35+ */
}

@media (max-width: 768px) {
  .gallery-item2 {
    float: none;
    width: 49%;
  }
}

@media (max-width: 30em) {
  .wrap {
    padding-left: 1em;
    padding-right: 1em;
  }

  .gallery-item {
    float: none;
    width: 48%;
  }
  .gallery-item2 {
    float: none;
    width: 100%;
  }
}