body {
  padding: 0;
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 15px;
  color: #666;
  line-height: 1.6em;
}

a {
  color: #666;
  text-decoration: none;
}

.container {
  width: 80%;
  margin: auto;
  overflow: auto;
}

header {
  background-color: #333;
  min-height: 55px;
  color: #fff;
}

header a {
  columns: #fff;
}

.logo {
  float: left;
  width: 30%;
  margin-top: 15px;
}

nav {
  float: right;
  width: 70%;
}

nav ul {
  float: right;
}

nav li {
  list-style: none;
  float: left;
  padding: 0 10px;
}

nav a {
  color: #fff;
  padding-bottom: 5px;
}

nav li.current a,
nav a:hover {
  color: #03899c;
  border-bottom: 3px solid #03899c;
}

section {
  padding: 20px 0;
  overflow: hidden;
}

.tagline {
  background-color: #03899c;
  color: #fff;
}

.tagline h1 {
  text-align: center;
  font-size: 35px;
}

#gallery {
  list-style: none;
  margin: 0;
  padding: 0;
  width: 100%;
}

#gallery li {
  display: block;
  float: left;
  width: 23%;
  cursor: pointer;
  border-radius: 5px;
  box-sizing: border-box;
  margin: 0 12px 7px 0;
  position: relative;
}

#gallery img {
  width: 100%;
  border-radius: 5px;
}

footer {
  background-color: #03899c;
  height: 55px;
  color: #fff;
  text-align: center;
  padding-top: 10px;
}

.overlay {
  display: none;
  background: #03899c url("./imgs/overlay.png") no-repeat top center;
  color: #fff;
  position: absolute;
  top: 0;
  left: 0;
  z-index: 100;
  width: 100%;
  height: 100%;
  padding: 20px;
  border-radius: 5px;
  box-sizing: border-box;
  pointer-events: none;
}

.overlay h3 {
  margin: 0;
  padding: 0;
}

@media (max-width: 768px) {
  .logo,
  nav {
    float: none;
    width: 100%;
    text-align: center;
  }

  nav ul,
  nav li {
    float: none;
    padding: 0;
  }

  nav li {
    margin-bottom: 15px;
  }

  #gallery li {
    width: 48%;
    margin-right: 8px;
  }
}

@media (max-width: 568px) {
  #gallery li {
    width: 100%;
    margin-right: 0;
  }
}