body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    align-content: center;
    text-align: center;
}

header {
    position: relative;
    background-color: white;
    width: 100%;
}

nav {
    background-color: white;
    list-style-type: none;
}
nav ul {
    margin: 0 auto;
    text-align: center;
    display: inline-block;
    list-style-type: none;
}


li {
    display: inline;
}

li a {
    transition-delay: .3s;
    transition: .3s ease-in-out;
}

li a:hover {
    color: red;
    font-size: 110%;
    transition-delay: .1s;
}

section {
    display: block;
    min-height: min-content;
    min-width: 400px;
    position: relative;
}

main section {
    position: relative;
    width: fit-content;
    align-content: center;
    margin: 0 auto;
}

iframe {
    display: block;
    margin: auto;
    transition: display 0.5s ease-in-out;
}


h1 a:hover {
    color: blueviolet;
    font-size: 110%;
    transition-delay: .1s;
}

h1 a {
    transition-delay: .3s;
    transition: .3s ease-in-out;
}

.show-player {
    display: block;
    opacity: 1;
    visibility: visible;
}

.hide-player {
    display: none;
    opacity: 0;
    visibility:hidden;
}

#container_player.show-player {
  animation: show-player 0.3s ease-in-out;
}

@keyframes show-player {
  from {
    display: none;
    visibility:hidden;
    opacity: 0;
    transform: translateY(-100%);
  }
  to {
    display: block;
    visibility: visible;
    opacity: 1;
    transform: translateY(0);
  }
}

#container_player.hide-player {
  animation: hide-player 0.3s ease-in-out;
}
@keyframes hide-player {
  from {
    display: block;
    visibility: visible;
    opacity: 1;
    transform: translateY(0%);
  }
  to {
    visibility: visible;
    display: none;
    opacity: 0;
    transform: translateY(-100%);
  }
}