#checklist {
  --background: #FFFFFF;
  --text: #333333;
  --check: #90D7F3;
  --disabled: #90D7F3;
  --width: 100%px;
  --height: 100%px;
  --border-radius: 25px;
  background: var(--background);
  width: var(--width);
  height: var(--height);
  border-radius: var(--border-radius);
  position: relative;
  box-shadow: 0 10px 30px rgba(65, 72, 86, 0.05);
  padding: 10px 45px;
  display: grid;
  grid-template-columns: 30px auto;
  align-items: center;
}
#checklist label {
  color: var(--text);
  position: relative;
  cursor: pointer;
  display: grid;
  align-items: center;
  width: -webkit-fit-content;
  width: -moz-fit-content;
  width: fit-content;
  transition: color 1s ease;
}
#checklist label::before, #checklist label::after {
  content: "";
  position: absolute;
}
#checklist label::before {
  height: 2px;
  width: 8px;
  left: -27px;
  background: var(--check);
  border-radius: 2px;
  transition: background 1s ease;
}
#checklist label:after {
  height: 4px;
  width: 4px;
  top: 8px;
  left: -25px;
  border-radius: 50%;
}
#checklist input[type=checkbox] {
  -webkit-appearance: none;
  -moz-appearance: none;
  position: relative;
  height: 15px;
  width: 15px;
  outline: none;
  border: 0;
  margin: 0 15px 0 0;
  cursor: pointer;
  background: var(--background);
  display: grid;
  align-items: center;
}
#checklist input[type=checkbox]::before, #checklist input[type=checkbox]::after {
  content: "";
  position: absolute;
  height: 2px;
  top: auto;
  background: var(--check);
  border-radius: 2px;
}
#checklist input[type=checkbox]::before {
  width: 0px;
  right: 60%;
  transform-origin: right bottom;
}
#checklist input[type=checkbox]::after {
  width: 0px;
  left: 40%;
  transform-origin: left bottom;
}
#checklist input[type=checkbox]:checked::before {
  -webkit-animation: check-01 0.4s ease forwards;
          animation: check-01 0.4s ease forwards;
}
#checklist input[type=checkbox]:checked::after {
  -webkit-animation: check-02 0.4s ease forwards;
          animation: check-02 0.4s ease forwards;
}
#checklist input[type=checkbox]:checked + label {
  color: var(--disabled);
  -webkit-animation: move 0.3s ease 0.1s forwards;
          animation: move 0.3s ease 0.1s forwards;
}
#checklist input[type=checkbox]:checked + label::before {
  background: var(--disabled);
  -webkit-animation: slice 0.4s ease forwards;
          animation: slice 0.4s ease forwards;
}
#checklist input[type=checkbox]:checked + label::after {
  -webkit-animation: firework 1s ease forwards 0.1s;
          animation: firework 1s ease forwards 0.1s;
}

@-webkit-keyframes move {
  50% {
    padding-left: 8px;
    padding-right: 0px;
  }
  100% {
    padding-right: 4px;
  }
}

@keyframes move {
  50% {
    padding-left: 8px;
    padding-right: 0px;
  }
  100% {
    padding-right: 4px;
  }
}
@-webkit-keyframes slice {
  60% {
    width: 100%;
    left: 4px;
  }
  100% {
    width: 100%;
    left: -2px;
    padding-left: 0;
  }
}
@keyframes slice {
  60% {
    width: 100%;
    left: 4px;
  }
  100% {
    width: 100%;
    left: -2px;
    padding-left: 0;
  }
}
@-webkit-keyframes check-01 {
  0% {
    width: 4px;
    top: auto;
    transform: rotate(0);
  }
  50% {
    width: 0px;
    top: auto;
    transform: rotate(0);
  }
  51% {
    width: 0px;
    top: 8px;
    transform: rotate(45deg);
  }
  100% {
    width: 5px;
    top: 8px;
    transform: rotate(45deg);
  }
}
@keyframes check-01 {
  0% {
    width: 4px;
    top: auto;
    transform: rotate(0);
  }
  50% {
    width: 0px;
    top: auto;
    transform: rotate(0);
  }
  51% {
    width: 0px;
    top: 8px;
    transform: rotate(45deg);
  }
  100% {
    width: 5px;
    top: 8px;
    transform: rotate(45deg);
  }
}
@-webkit-keyframes check-02 {
  0% {
    width: 4px;
    top: auto;
    transform: rotate(0);
  }
  50% {
    width: 0px;
    top: auto;
    transform: rotate(0);
  }
  51% {
    width: 0px;
    top: 8px;
    transform: rotate(-45deg);
  }
  100% {
    width: 10px;
    top: 8px;
    transform: rotate(-45deg);
  }
}
@keyframes check-02 {
  0% {
    width: 4px;
    top: auto;
    transform: rotate(0);
  }
  50% {
    width: 0px;
    top: auto;
    transform: rotate(0);
  }
  51% {
    width: 0px;
    top: 8px;
    transform: rotate(-45deg);
  }
  100% {
    width: 10px;
    top: 8px;
    transform: rotate(-45deg);
  }
}
@-webkit-keyframes firework {
  0% {
    opacity: 1;
    box-shadow: 0 0 0 -2px #FF0000, 0 0 0 -2px #FFFF00, 0 0 0 -2px #008000, 0 0 0 -2px #0000FF, 0 0 0 -2px #4B0082, 0 0 0 -2px #FFA500;
  }
  30% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    box-shadow: 0 -15px 0 0px #FF0000, 14px -8px 0 0px #FFFF00, 14px 8px 0 0px #008000, 0 15px 0 0px #0000FF, -14px 8px 0 0px #4B0082, -14px -8px 0 0px #FFA500;
  }
}
@keyframes firework {
  0% {
    opacity: 1;
    box-shadow: 0 0 0 -2px #FF0000, 0 0 0 -2px #FFFF00, 0 0 0 -2px #008000, 0 0 0 -2px #0000FF, 0 0 0 -2px #4B0082, 0 0 0 -2px #FFA500;
  }
  30% {
    opacity: 1;
  }
  100% {
    opacity: 0;
    box-shadow: 0 -15px 0 0px #FF0000, 14px -8px 0 0px #FFFF00, 14px 8px 0 0px #008000, 0 15px 0 0px #0000FF, -14px 8px 0 0px #4B0082, -14px -8px 0 0px #FFA500;
  }
}
body {
  background: #C5EAF9;
  height: 100%;
  font: 400 16px "Varela Round", sans-serif;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}