style.css

@import url("https://fonts.googleapis.com/css?family=Montserrat");

html {
  box-sizing: border-box;
  background: url("images/rawe.jpg") center no-repeat;
  background-size: cover;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  text-align: center;
  font-family: "Montserrat", Futura, "Trebuchet MS", Arial, sans-serif;
}

*,
*:before,
*:after {
  box-sizing: inherit;
}

.wrapper {
  padding: 20px;
  max-width: 400px;
  background: rgba(245, 245, 245, 0.9);
  box-shadow: 0 0 0 10px rgba(0, 0, 0, 0.1);
}

h2 {
  text-align: center;
  margin: 0;
  font-weight: 200;
}

.tasks {
  margin: 0;
  padding: 0;
  text-align: left;
  list-style: none;
}

.tasks li {
  border-bottom: 1px solid rgba(10, 10, 10, 0.2);
  padding: 10px;
  display: flex;
}

.tasks li .done {
  text-decoration: line-through;
  color: rgba(10, 10, 10, 0.2);
}

.tasks label {
  flex: 1;
  cursor: pointer;
  border-right: 1px solid grey;
  margin-right: 5px;
}

.add-tasks {
  margin-top: 20px;
}

.add-tasks input {
  padding: 10px;
  outline: 0;
  border: 1px solid rgba(0, 0, 0, 0.1);
}

.del {
  -moz-user-select: none;
  -webkit-user-select: none;
  user-select: none;
  padding: 1px 6px;
  margin: auto;
}

.del:hover {
  background-color: rgba(250, 1, 1, 0.6);
}

.footer {
  background: rgba(255, 255, 255, 0.75);
  position: fixed;
  bottom: 0;
  left: 0%;
  right: 0%;
  font-size: 0.7em;
  cursor: pointer;
}

@media only screen and (max-width: 992px) {
  .wrapper {
    max-width: 70vw;
  }
}