*, :after, :before { box-sizing: border-box }

body {
  margin: 0;
  font-family: sans-serif
}

.gallery-container {
  width: 900px;
  margin-left: auto;
  margin-right: auto;
  display: -ms-grid;
  display: grid;
-ms-grid-columns:(1fr)[4];
  grid-template-columns: repeat(4, 1fr);
  grid-gap: .5em
}

.gallery-img {
  display: block;
  max-width: 100%;
  cursor: pointer
}

.lightbox-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0,0,0,.8);
  display: -ms-flexbox;
  display: flex;
  z-index: 1
}

.lightbox-container {
  position: relative;
  margin: auto;
  background: #fff;
  padding: 1em;
  border-radius: .2em
}

.close-modal {
  background: tomato;
  color: #fff;
  position: absolute;
  width: 1.8em;
  height: 1.8em;
  text-align: center;
  line-height: 1.8em;
  top: -.9em;
  right: -.9em;
  border-radius: 50%;
  cursor: pointer
}

.lightbox-description {
  text-align: center;
  font-size: 1.1em
}

.lightbox-navigation {
  display: -ms-flexbox;
  display: flex;
  -ms-flex-pack: justify;
  justify-content: space-between;
  font-size: .9em;
  opacity: .8
}

.lightbox-navigation__button {
  text-decoration: none;
  color: tomato
}

h1 { text-align: center }

article {
  width: 70%;
  margin: auto
}

.animated-scroll__menu {
  display: -ms-flexbox;
  display: flex;
  -ms-flex-line-pack: center;
  align-content: center;
  -ms-flex-pack: center;
  justify-content: center;
  list-style-type: none
}

.animated-scroll__menu li { margin: 1em }

.animated-scroll__content {
  padding-top: 4em;
  line-height: 1.8
}