/* coded by Irena Popova, Germany*/
@import url('https://fonts.googleapis.com/css?family=Open+Sans');

body {
  margin: 0;
  background-color: #fff;
  font-family: 'Open Sans', sans-serif;
  font-size: 1.1em;
  color: #050709;
  overflow: hidden;
}
#menu {
  display: none;
}
#navbar {
  float: left;
  top: 0;
  position: fixed;
  height: 100%;
  overflow: auto;
  background-color: #bdf6fd;
  width: 300px;
}
#navbar header {
  text-align: center;
  color: #386975;
  font-size: 1.2em;
}
.nav-link {
  display:block;
  color: #050709;
  font-size: 1em;
  text-decoration: none;
  padding: 20px;
  border-top: 1px solid #386975;
  height: auto;
}
.nav-link:hover {
  animation-name: background-hover;
  animation-duration: 0.7s;
  animation-fill-mode: forwards;
}
@keyframes background-hover {
  100% {
    background-color: #74f7f2;
    padding-left: 30px;
  }
}
.nav-link:active {
  color: #386975;
}
#page {
  /* for the cool scrolling effect! */
  overflow: scroll;
  scroll-behavior: smooth;
  height: 100vh;
  overflow-x: hidden;
}

.main-section {
  margin: 30px 40px 0 340px;
  margin-left: 340px;
  margin-right: 40px;
  z-index: -10;
}
.main-section h2 {
  font-size: 30px;
  color: #386975;
}
.main-section a {
  color: #386975;
}
.main-section a:visited {
  color: #204a54;
}
pre, code {
  background-color: #d5f3f7;
}
pre {
  border: solid 0.5px #386975;
  padding: 15px;
  border-radius: 10px;
  white-space: pre-wrap;
}
p code, li code {
  font-weight: bold;
}
footer {
  background-color: #b3f3fb;
  text-align: center;
  padding: 10px;
  margin-left: 300px;
  font-size: 0.8em;
}
footer a {
  color: #386975;
}
footer a:visited {
  color: #204a54;
}
@media screen and (max-width: 700px) {
  #navbar {
    width: 100%;
    position: absolute;
    top: 80px;
    left:0;
    margin: 0;
    height: initial;
    font-size: 1em;
    max-height: 0;
    overflow: scroll;
    z-index: 30;
  }
  #navbar header {
    font-size: 1.1em;
  }
  .nav-link {
    padding: 10px;
  }
  .main-section {
    margin: auto;
  }
  #page {
    padding: 4%;
    overflow: auto;
    margin: auto;
    scroll-behavior: smooth;
    height: 100vh;
  }
  footer {
    margin: 0;
  }
  header h1 {
    display:none;
  }
  #menu {
    display: block;
  }
  input#menu {
    display:none;
  }
  label {
    font-size: 30px;
    color: #386975;
    cursor: pointer;
    background: url("https://s15.postimg.cc/cpsibt28r/menu.png") no-repeat 2% 50%;
    padding: 30px 0 30px 60px;
    line-height: 1.5em;
    transition: 0.3s;
  }
  input:checked~label {
    background: url("https://s15.postimg.cc/uva23rbqz/error.png") no-repeat 2% 50%;
  }
  input:checked~#navbar {
    max-height: 80%;
    transition: 0.5s;
  }
  .back-to-top div{
    background: url("https://s15.postimg.cc/9itty1tzv/play-button.png") no-repeat;
    transform: rotate(-90deg);
    width: 24px;
    padding: 5px;
    height: 24px;
    cursor: pointer;
  }
}