style.css

@import url('https://fonts.googleapis.com/css2?family=Kalam:wght@300&family=Pacifico&display=swap');

body {
  background: rgb(82, 171, 110) url('bg-pic.png') no-repeat center;
  background-attachment: fixed;
  background-size: fixed;
  font-size: 20px;
  color: #7CEC9F;
  display: flex;
  justify-content: center;
}

.container {
  font-family: 'Kalam', cursive;
  overflow: auto;
  width: 350px;
  min-height: 87vh;
  margin: 25px auto auto auto;
  border-radius: 30px;
  text-align: center;
  box-shadow: 0px 0px 80px 5px #07192f;
}

header {
  display: flex;
  justify-content: center;
  flex-direction: row;
  align-items: center;
  font-family: 'Pacifico', cursive;
  border-radius: 30px 30px 0px 0px;
  background-size: cover;
  margin-bottom: 20px;
  width: 100%;
  height: 170px;
}

h1 {
  text-decoration: overline;
}

#reset, #remove {
  border: none;
  padding: 7px 10px;
  width: 15vh;
  border-radius: 20px;
  font-family: 'Times New Roman', Times, serif;
  font-size: 18px;
  text-transform: uppercase;
  margin: 10px auto;
  box-shadow: 0px 4px 8px 0px rgba(76, 76, 76, 0.741);
  outline: none;
}

#reset:active, #remove:active {
  transform: translateY(3px);
  transition: 0.3s ease;
  box-shadow: none;
}

button#remove {
  background: rgb(255, 194, 194);
}

button#reset {
  background-color: rgb(223, 255, 212);
}

input#textinput {
  border: none;
  border-radius: 20px;
  height: 1.9em;
  margin-left: 2px;
  width: 65%;
  outline: none;
  padding: 0px 50px 0px 12px;
  font-family: 'Times New Roman', Times, serif;
  font-size: 1em;
}

input#textinput:focus {
  box-shadow: 0px 4px 8px 0px rgba(76, 76, 76, 0.741);
}

#addButton {
  margin-left: -52px;
  text-align: center;
  vertical-align: middle;
  font-size: 35px;
  color: #07192f;
  background-color: rgba(255, 255, 255, 0);
  border: none;
  outline: none;
}

#addButton:active {
  color: rgb(97, 181, 123);
}

ul#list {
  margin: 10px auto;
}

ul li {
  list-style: none;
  text-align: start;
  background-color: #7CEC9F;
  color: #07192f;
  width: 85%;
  padding: 3px;
  border: 2px solid #07192f;
  border-radius: 10px;
  box-shadow: inset 0px 0px 4px #07192f;
}

ul li input[type="checkbox"] {
  position: absolute;
  opacity: 0;
  cursor: pointer;
  height: 0;
  width: 0;
}

.fa-check {
  color: rgb(72, 137, 93);
  margin: 3px;
  font-size: 20px;
}

ul li input[type="checkbox"]:checked + label {
  color: rgb(108, 174, 129);
  text-decoration: line-through;
}

#alert {
  display: none;
}

.visual {
  display: block !important;
}