style.css

@charset "UTF-8";
@import url(https://fonts.googleapis.com/css?family=Open+Sans:400,600);



.todo-cmp {
  background: #ffffff;
  color: #497081;
  padding: 1px 10px;
  border-radius: 5px;
  box-shadow: 2px 2px 14px rgba(0, 0, 0, 0.15);
  width: 180px;
}
.todo-cmp__header {
  text-align: center;
  padding: 5px 0;
  border-bottom: 1px solid #ddd;
}
.todo-cmp__header h2 {
  font-weight: 600;
  font-size: 1.2rem;
  margin: 4px auto;
  padding: 0;
}
.todo-cmp__header p {
  padding: 0 0 5px;
  margin: 4px auto;
  font-size: 0.8rem;
}
.todo-cmp__list {
  list-style: none;
  padding: 0;
}
.todo-cmp__list li {
  padding: 2px 0 15px;
  margin: 0;
  text-align: left;
  width: 100%;
}
.todo-cmp__list li label {
  cursor: pointer;
  font-size: 0.82rem;
  width: 100%;
  display: block;
}
.todo-cmp__list li label input {
  float: right;
  opacity: 0;
}
.todo-cmp__list li label span {
  position: relative;
  display: block;
  transition: all 550ms ease-in-out;
}
.todo-cmp__list li label input + span::after {
  content: "";
  display: block;
  border: 1px solid #497081;
  border-radius: 13px;
  height: 13px;
  width: 13px;
  position: absolute;
  right: 0;
  top: 1px;
  z-index: 10;
  transition: all 550ms cubic-bezier(0.68, -0.55, 0.265, 1.55);
  transition-timing-function: cubic-bezier(0.68, -0.55, 0.265, 1.55);
  /* https://matthewlein.com/tools/ceaser */
}
.todo-cmp__list li label input  + span::before {
  content: "✔";
  display: block;
  font-size: 22px;
  height: 13px;
  width: 13px;
  position: absolute;
  right: -2px;
  top: -8px;
  z-index: 10;
  opacity: 0;
}
.todo-cmp__list li label input:checked + span {
  color: #ccc;
  transition: all 550ms ease-in-out;
}
.todo-cmp__list li label input:checked + span::after {
  opacity: 0;
  height: 17px;
  width: 17px;
  top: -2px;
  right: -2px;
}
.todo-cmp__list li label input:checked + span::before {
  opacity: 1;
  transition: all 550ms ease-in-out;
}