/* button
------------------------- */

.button {
  display: inline-block;
  padding: 5px 15px;
  margin-bottom: 10px;
  background: #f6b20e;
  border: none;
  /*background-image: linear-gradient( to bottom, hsla(0, 0%, 0%, 0), hsla(0, 0%, 0%, 0.2) );*/
  color: #222;
  font-weight: 500;
  cursor: pointer;
}

.button:hover {
  background-color: #CCCCCC;
  color: #222;
}

.button:active,
.button.is-checked,
.button.is-selected {
  background-color: #6C6C6C;
}

.button.is-checked,
.button.is-selected {
  color: white;
 
}

/*
.button:active {
  box-shadow: inset 0 1px 10px hsla(0, 0%, 0%, 0.8);
}
*/

/* hide radio inputs */
.button input[type="radio"] { display: none; }

/* ---- button-group ---- */

.button-group:after {
  content: '';
  display: block;
  clear: both;
}

.button-group .button {
  float: left;
 
  border-radius: 0.5em 0.5em 0.5em 0.5em;
  margin-right: 1px;
}








/* element-item
------------------------- */

.element-item {
  position: relative;
  float: left;
  width: 180px;
  height: 120px;
  margin: 5px;

 
  color: #262524;
}

.element-item > * {
  margin: 0;
  padding: 0;
}






.element-item.alkali          { background: #F00; background: hsl(   0, 100%, 50%); }
.element-item.alkaline-earth  { background: #F80; background: hsl(  36, 100%, 50%); }
.element-item.lanthanoid      { background: #FF0; background: hsl(  72, 100%, 50%); }
.element-item.actinoid        { background: #0F0; background: hsl( 108, 100%, 50%); }
/*.element-item.transition      { background: #0F8; background: hsl( 144, 100%, 50%); }*/
.element-item.post-transition { background: #0FF; background: hsl( 180, 100%, 50%); }
.element-item.metalloid       { background: #08F; background: hsl( 216, 100%, 50%); }
.element-item.diatomic        { background: #00F; background: hsl( 252, 100%, 50%); }
.element-item.halogen         { background: #F0F; background: hsl( 288, 100%, 50%); }
.element-item.noble-gas       { background: #F08; background: hsl( 324, 100%, 50%); }