mobile.css

@media screen and (max-width: 900px) {

  .advert {
    display: block;
    margin: auto;
    height: 150vh;
    overflow: hidden;
  }
  .advert img {
    float: none;
    width: inherit;
    margin: auto;

  }
  .flex-container{
    width: 80%;
  }

  .about {
    display: block;
    text-align: center;
    margin: auto;
    height: inherit;
  }

  .about img {
    float: none;
    width: 80%;
  }
  iframe {
    width: 100%;
  }
}

/* Responsive layout - makes a two column-layout instead of four columns */
@media screen and (max-width: 900px) {
  .column {
    width: 50%;
  }
}

/* Responsive layout - makes the two columns stack on top of each other instead of next to each other */
@media screen and (max-width: 600px) {
  .column {
    width: 100%;
  }
}

@media only screen and (max-width: 700px) {
  .grid {
    width: 49.99999%;
    margin: 6px 0;
  }
}

@media only screen and (max-width: 500px) {
  .grid {
    width: 100%;
    margin: auto;
  }
  .column {
    max-width: 80%;
  }
}


/* Tablet menu */
@media all and (min-width: 700px) {
  .menu {
    justify-content: center;
  }
  .logo {
    flex: 1;
  }
  .item.button {
    width: auto;
    order: 1;
    display: block;
  }
  .toggle {
    flex: 1;
    text-align: right;
    order: 2;
  }
  /* Button up from tablet screen */
  .menu li.button a {
    padding: 10px 15px;
    margin: 5px 0;
  }
  .button a {
    background: #0080ff;
    border: 1px royalblue solid;
  }
  .button.secondary {
    border: 0;
  }
  .button.secondary a {
    background: transparent;
    border: 1px #0080ff solid;
  }
  .button a:hover {
    text-decoration: none;
  }
  .button:not(.secondary) a:hover {
    background: royalblue;
    border-color: darkblue;
  }
}
/* Desktop menu */
@media all and (min-width: 960px) {
  .menu {
    align-items: flex-start;
    flex-wrap: nowrap;
    background: none;
  }
  .logo {
    order: 0;
  }
  .item {
    order: 1;
    position: relative;
    display: block;
    width: auto;
  }
  .button {
    order: 2;
  }
  .submenu-active .submenu {
    display: block;
    position: absolute;
    left: 0;
    top: 68px;
    background: #111;
  }
  .toggle {
    display: none;
  }
  .submenu-active {
    border-radius: 0;
  }
}