html {
  height: 100%;
  box-sizing: border-box;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

body {
  position: relative;
  margin: 0;
  min-height: 100%;
}

main {
    padding-bottom: 6rem;
}

.footer {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 250px;
  padding: 1rem;
  background-color: var(--clr-bg-a);
  text-align: center;
  border-top: 1px solid var(--clr-line-a);
  transition: 300ms ease-in-out;
}

#sidebar.close ~ main .footer,
body:has(#sidebar.close) .footer {
  left: 50px; 
}

@media(max-width: 900px){
  .footer {
    display: none;
  }
}