* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  min-height: 100vh;
  background-image: linear-gradient(120deg, #09203f, #537895);
  color: rgb(100, 205, 247);
  font-family: "Poppins", sans-serif;
}

h1 {
  font-size: rem;
  position: relative;
}

h1::after {
  position: absolute;
  content: "";
  height: 3px;

  /* centering the line */
  bottom: -4px;
  margin: 0 auto;
  left: 0;
  right: 0;

  width: 50%;
  background: rgb(0, 255, 200);

  animation: hell;

  animation-duration: 3s;
  animation-iteration-count: infinite;
  animation-timing-function: ease-in-out;
}

@keyframes hell {
  0% {
    width: 0;
  }

  90% {
    width: 80%;
  }
  100% {
    opacity: 0;
  }
}
header {
  margin-top: 2%;
}
header,
form {
  height: 20vh;

  display: flex;
  justify-content: center;
  align-items: center;
}

header {
  flex-direction: column;
}

/* Alert Decorations */
.input-error {
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  background-color: red;
  margin-top: 3%;

  padding: 0.3rem 1rem;

  display: none;
}

.input-success {
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  background-color: green;
  margin-top: 3%;
  padding: 0.3rem 1rem;
  display: none;
}
.input-undo-success {
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  background-color: green;
  margin-top: 3%;
  padding: 0.3rem 1rem;
  display: none;
}
.input-delete-success {
  display: flex;
  justify-content: center;
  align-items: center;
  color: white;
  background-color: rgb(0, 195, 255);
  margin-top: 3%;
  padding: 0.3rem 1rem;
  display: none;
}

.todo-input,
form button {
  padding: 1rem;
  font-size: 2rem;
  background-color: white;
  outline: none;
  border: none;
  transition: 0.5s ease;
}
.todo-input::placeholder {
  font-size: 20px;
  opacity: 0.13;
}
form button {
  color: rgb(100, 205, 247);
  cursor: pointer;
}
form button:hover {
  background-color: rgb(100, 205, 247);
  color: white;
}

.todo-container {
  display: flex;
  justify-content: center;
  align-items: center;
}
.todo-list {
  list-style-type: none;
  min-width: 40%;
}

.todo {
  min-width: 80%;
  margin: 10px;
  background-color: white;
  color: black;
  font-size: 1.4rem;
  display: flex;
  justify-content: space-between;
  transition: 1s;
}

.todo li {
  flex: 1;
  padding: 0 0.8rem;
  align-self: center;
}
.completed-btn,
.trash-btn {
  padding: 0.8rem;
  font-size: large;
  outline: none;
  border: none;
  background-color: rgb(100, 205, 247);
  color: white;
  cursor: pointer;
  transition: 0.4s;
}
.completed-btn {
  background-color: rgb(0, 255, 200);
}
.completed-btn:hover {
  color: rgb(0, 255, 200);
  background-color: white;
}
.trash-btn:hover {
  background-color: white;
  color: rgb(100, 205, 247);
}

.fa-check,
.fa-trash {
  pointer-events: none;
}

.completed {
  text-decoration: line-through;
  opacity: 0.4;
  transition: 0.5s;
}

.fall {
  transform: translateY(8rem) rotateZ(20deg);
  transition: 0.7s;
  opacity: 0;
}

/* filter style section */

select {
  -webkit-appearance: none;
  appearance: none;
  outline: none;
  border: none;
}

.select {
  margin: 1rem;
  position: relative;
  overflow: hidden;
}

select {
  color: black;
  width: 12rem;
  padding: 1.6rem;
  cursor: pointer;
}
.select::after {
  content: "\25BC";
  position: absolute;
  background: rgb(100, 205, 247);
  color: white;
  top: 0;
  right: 0;
  padding: 1.6rem;
  pointer-events: none;

  transition: 0.4s;
}
.select:hover::after {
  background: white;
  color: rgb(100, 205, 247);
}