:root {
  --background-color: rgb(167, 167, 167);
  --itembkg: white;
}

body {
  background-color: var(--background-color);
}

#arrow {
  width: 0; 
  height: 0; 
  border-left: 5px solid transparent;
  border-right: 5px solid transparent;
  border-top: 10px solid rgb(255, 0, 0);
}

nav ul{
  list-style: none;
  margin: 0;
  padding: 0;
}

#range {
  display: none;
}

.pcenter{
  display: none;
}

.active{
  display: block;
}

.arrowactive {
  rotate: 180deg;
}

.link {
  text-decoration: none;
  color: black;
}

#slider {
  appearance: none;
  width: 100%;
  height: 25px;
  background: var(--background-color);
  outline: none;
}

.mar20 {
  margin: 20;
}

.item {
  background-color: var(--itembkg);
  border: 1px solid green;
  width: 100%;
  margin: 0 auto;
  padding: 10px;
}

#container {
  margin: 0 auto;
  width: 40%;
}

#command {
  display: block;
  margin: 0 auto;
}

.item img {
  display: block;
  margin: 0 auto;
}

h1, h3 {
  text-align: center;
}

footer {
  padding: 20px;
  text-align: center;
}


@media (min-width: 700px) {
  .flex {
    display: flex;
  }

  .flex1 {
    flex: 1;
  }

  .item {
    width: 100%;
  }

  #arrow {
    display: none;
  }

  .pcenter {
    display: block;
  }

  nav ul{
    text-align: center;
    margin: 10px;
  }

  #e1::after {
    content: "|";
  }

  nav ul li{
    display: inline-block;
  }
}