* {
  box-sizing: border-box;
}

form ul {
  list-style: none;
}

label {
  cursor: pointer;
  display: inline-block;
}

input[type="checkbox"],
input[type="radio"] {
  border: 0;
  clip: rect(0 0 0 0);
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  width: 1px;
}

input[type="checkbox"] + label,
input[type="radio"] + label {
  position: relative;
  padding: 5px;
  padding-left: 25px;
  vertical-align: middle;
  -webkit-user-select: none;
     -moz-user-select: none;
      -ms-user-select: none;
          user-select: none;
}
input[type="checkbox"] + label:before,
input[type="radio"] + label:before {
  box-sizing: content-box;
  content: '';
  color: #900;
  position: absolute;
  top: 50%;
  left: 0;
  width: 12px;
  height: 12px;
  margin-top: -7px;
  border: 1px solid #fff;
  text-align: center;
  border-radius:2px;
}
input[type="checkbox"] + label:after,
input[type="radio"] + label:after {
  box-sizing: content-box;
  content: '';
  background-color: #900;
  position: absolute;
  top: 50%;
  left: 4px;
  width: 10px;
  height: 10px;
  margin-top: -5px;
  -webkit-transform: scale(0);
          transform: scale(0);
  -webkit-transform-origin: 50%;
          transform-origin: 50%;
  -webkit-transition: -webkit-transform 200ms ease-out;
  transition: -webkit-transform 200ms ease-out;
  transition: transform 200ms ease-out;
  transition: transform 200ms ease-out, -webkit-transform 200ms ease-out;
}

input[type="checkbox"] + label:after {
  background-color: transparent;
  top: 50%;
  left: 3px;
  width: 8px;
  height: 3px;
  margin-top: -4px;
  border-style: solid;
  border-color: #fff;
  border-width: 0 0 2px 2px;
  -webkit-border-image: none;
       -o-border-image: none;
          border-image: none;
  -webkit-transform: rotate(-45deg) scale(0);
          transform: rotate(-45deg) scale(0);
  -webkit-transition: none;
  transition: none;
}
input[type="checkbox"]:checked + label:before {
  content: '';
 /* background:#fff; */
}
input[type="radio"] + label:before, input[type="radio"] + label:after {
  border-radius: 50%;
}

.error-msg {
  display: block;
  color: red;
  max-height: 0;
  overflow: hidden;
  -webkit-transition: max-height 500ms ease-out;
  transition: max-height 500ms ease-out;
  will-change: max-height;
}

:required:not(:focus) ~ .error-msg,
:invalid:required ~ .error-msg {
  max-height: 9em;
}