web-html5-scripts/templates-and-navigation/full-page-nav/style.css

html, body {
  max-height: 100%;
  height: 100%;
  padding: 0;
  margin: 0;
  font-family: "Helvetica Neue","Helvetica",Arial,sans-serif;
  background: #ee0979;
  /* fallback for old browsers */
  background: -webkit-linear-gradient(to right, #ff6a00, #ee0979);
  /* Chrome 10-25, Safari 5.1-6 */
  background: linear-gradient(to right, #ff6a00, #ee0979);
  /* W3C, IE 10+/ Edge, Firefox 16+, Chrome 26+, Opera 12+, Safari 7+ */
}

* {
  box-sizing: border-box;
}

#menu-toggle {
  position: fixed;
  transform: translateX(-500px);
}
#menu-toggle:checked ~ .hamburger > span:first-child {
  transform: translateY(8px) rotate(45deg);
}
#menu-toggle:checked ~ .hamburger > span:nth-child(2) {
  opacity: 0;
}
#menu-toggle:checked ~ .hamburger > span:last-child {
  transform: translateY(-8px) rotate(-45deg);
}
#menu-toggle:checked ~ .wrapper {
  overflow: hidden;
}
#menu-toggle:checked ~ .wrapper nav {
  transform: translateX(0);
}
#menu-toggle:checked ~ .wrapper nav ul li {
  opacity: 1;
  transform: translateY(0);
}
#menu-toggle:checked ~ .wrapper .page-content {
  filter: blur(5px);
  opacity: .1;
}

.wrapper {
  max-width: 100%;
  max-height: 100%;
  overflow: auto;
}

.page-content {
  display: block;
  transition: .5s ease-in-out;
}

.page-content {
  background: white;
  padding: 80px 20px 20px 20px;
}
.page-content p {
  margin: 0 auto 20px auto;
  max-width: 800px;
}
.page-content p:last-child {
  margin-bottom: 0;
}

.hamburger {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 100;
  background: rgba(255, 255, 255, 0.85);
  height: 40px;
  width: 40px;
  border-radius: 5px;
  backdrop-filter: blur(5px);
}
.hamburger > span {
  display: block;
  width: calc(100% - 16px);
  height: 4px;
  background: black;
  border-radius: 4px;
  position: absolute;
  left: 8px;
  transition: 0.25s cubic-bezier(0.86, 0, 0.07, 1);
}
.hamburger > span:first-child {
  top: 10px;
}
.hamburger > span:nth-child(2) {
  top: 18px;
}
.hamburger > span:last-child {
  top: 26px;
}

nav {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
  transform: translateY(100%);
  display: flex;
  align-items: center;
  justify-content: center;
}
nav ul {
  margin: 0;
  padding: 0;
  list-style-type: none;
  text-align: center;
}
nav ul li {
  font-size: 25px;
  line-height: 50px;
  opacity: 0;
  transform: translateY(100px);
  transition: 0.6s cubic-bezier(0.86, 0, 0.07, 1);
}
nav ul li a {
  display: block;
  text-decoration: none;
  color: white;
}
nav ul li:first-child {
  transition-delay: .1s;
}
nav ul li:nth-child(2) {
  transition-delay: .2s;
}
nav ul li:nth-child(3) {
  transition-delay: .3s;
}
nav ul li:nth-child(4) {
  transition-delay: .4s;
}