style.css

* {
  margin: 0;
  padding: 0;
  font-family: "Poppins", sans-serif;
  box-sizing: border-box;
}
.container {
  width: 100%;
  min-height: 100vh;
  background: linear-gradient(135deg, #fb9e1d, #fe2f73);
  padding: 10px;
}
.todo-app {
  width: 100%;
  max-width: 540px;
  background: #fff;
  margin: 100px auto 20px;
  padding: 40px 30px 70px;
  border-radius: 10px;
}
.todo-app h2 img {
  width: 30px;
  margin-left: 10px;
}
.row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #efe8e2;
  border-radius: 30px;
  padding-left: 20px;
  margin-bottom: 25px;
}
input {
  flex: 1;
  border: none;
  outline: none;
  background: transparent;
  padding: 10px;
  font-size: 14px;
}
button {
  border: none;
  outline: none;
  padding: 16px 50px;
  background: #ff5945;
  color: #fff;
  font-size: 16px;
  cursor: pointer;
  border-radius: 40px;
}
ul li {
  list-style: none;
  font-size: 17px;
  padding: 12px 8px 12px 50px;
  user-select: none;
  cursor: pointer;
  position: relative;
}
ul li::before {
  content: "";
  position: absolute;
  height: 28px;
  width: 28px;
  border-radius: 50%;
  background-image: url(images/unchecked.png);
  background-size: cover;
  background-position: center;
  top: 12px;
  left: 8px;
}
ul li.checked {
  color: #555;
  text-decoration: line-through; /*yazının üstünü çizer*/
}
ul li.checked::before {
  background-image: url(images/check-circle-fill.svg);
}
ul li span {
  position: absolute;
  right: 0;
  top: 5px;
  width: 40px;
  height: 40px;
  font-size: 22px;
  color: #555;
  line-height: 40px;
  text-align: center;
  border-radius: 50%;
}
ul li span:hover { /*carpı iconun imleç ile geldiğimizde arka plan rengi değisiyor*/
  background: #edeef0;
}

.navigation {
  display: flex;
  justify-content: flex-end;
}

.navigation a {
  display: inline-block;
  margin-left: 10px;
  color: #fff;
  text-decoration: none;
  font-size: 18px;
}

.navigation a:hover {
  transform: scale(1.1);
}
.form-container {
  width: 100%;
  max-width: 540px;
  background: #fff;
  margin: 100px auto 20px;
  padding: 40px 30px 70px;
  border-radius: 10px;
}

.form-container h2 {
  text-align: center;
  margin-bottom: 40px;
  color: #333;
}

.form-container .row {
  display: flex;
  flex-direction: column;
  margin-bottom: 25px;
}

.form-container input {
  width: 100%;
  padding: 10px;
  border: 1px solid #ccc;
  border-radius: 5px;
  margin-bottom: 15px;
  font-size: 16px;
}

.form-container button {
  width: 100%;
  padding: 15px;
  border: none;
  border-radius: 5px;
  background-color: #fb9e1d;
  color: #fff;
  font-size: 18px;
  cursor: pointer;
}

.form-container button:hover {
  background-color: #fe2f73;
}