body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background: #f4f4f4;
    color: #222;
    display: flex;
    flex-direction: column;
    align-items: center;
	overflow:hidden;
  }

  h1 {
    position:fixed;
    top:0;
    width: 100%;
    text-align: center;
    background: #222;
    color: white;
    margin: 0;
    padding: 8px 0;
    font-size: 1.6rem;
	z-index:9999;
  }
.menu_bottom{
    display: flex;
    flex-wrap: nowrap;
	justify-content: space-between;
    padding: 5px 0 10px;
    width: 100%;
	position: fixed;
    bottom: 0;
    background-color: #fff;
	z-index:9999;
	box-shadow: 0 0 15px rgba(0, 0, 0, 0.3);

}
  .menu_bottom .img_content{width:25%;text-align:center;}
  .menu_bottom img {
	max-height:45px;    
	margin: 0 8px;
  }
  .buttons {
    display: flex;
    flex-wrap: nowrap;
    justify-content: space-evenly;
    gap: 15px;
	margin-right:15px;
	flex:1;
  }

  button {
    flex: 1 1 45%;
    border: none;
    color: white;
    padding: 12px;
    border-radius: 2px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.2s;
	width:45px;
	height:45px;
	background-color: #fff;
	background-repeat:no-repeat;
	background-position: center center;
  }
  button.btn_poules {
	background-image:url(/src/btn-poules.png);
  }
  button.btn_tab {
	background-image:url(/src/btn-tab.png);
  }
  button.btn_class {
	background-image:url(/src/btn-class.png);
  }
  button:hover {
    background-color: #eee;
  }

  iframe {
    width: 100%;
    height: calc(100vh - 131px);
    border: 0px solid #fff;
    background: white;
  }

  @media (min-width: 600px) {
    button {
      flex: 1 1 20%;
    }
  }
.sheet-frame-wrap {
  --visible-height: calc(100vh - 34px);
  --topbar: -15px;
  width: 100%;
  height: calc(var(--visible-height));
  overflow: hidden;
  position: relative;
}

.sheet-frame-wrap iframe {
  width: 100%;
  height: calc(var(--visible-height) + var(--topbar));
  border: 0;
  display: block;
  transform: translateY(calc(var(--topbar) * -1));
  -webkit-transform: translateY(calc(var(--topbar) * -1));
  background-image:url(/src/loading_icon.gif);
  background-repeat:no-repeat;
  background-position: center center;
}