style.css

@import url("https://fonts.googleapis.com/css2?family=Roboto:ital,wght@0,100;0,300;0,400;0,500;0,700;0,900;1,100;1,300;1,400;1,500;1,700;1,900&display=swap");

* {
  margin: 0;
  padding: 0;
  font-family: "Roboto", sans-serif;
}

body {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100vh;
}

.container {
  width: 500px;
  /* border: 1px solid; */
}

.container input {
  width: 95.8%;
  border: none;
  margin-bottom: 2px;
  padding: 20px 10px;
  border-radius: 5px;
  text-align: right;
  font-family: "Roboto", sans-serif;
  color: #fff;
  font-size: 1.3rem;
  background-color: #323232;
}

.container input:focus {
  outline: none;
}

.btn-container {
  display: grid;
  width: 100%;
  grid-template-columns: repeat(4, 1fr);
  gap: 3px;
}

.btn-container button {
  padding: 10px;
  font-size: 1.3rem;
  border-radius: 5px;
  border: none;
  transition: all 0.3s;
}

.operators {
  background-color: #323232;
  color: #fff;
  font-weight: 600;
}

.operators:hover {
  color: #fff;
  background-color: #3b3b3b;
  font-weight: 600;
  cursor: pointer;
}

.numbers:hover {
  background-color: #323232;
  color: #fff;
  font-weight: 600;
  cursor: pointer;
}

.numbers {
  color: #fff;
  background-color: #3b3b3b;
  font-weight: 600;
}

#equal {
  color: #323232;
  background-color: #ff8780;
}

#equal:hover {
  background-color: #f59590;
  cursor: pointer;
}

footer {
  margin-top: 40px;
  text-align: center;
}

footer p{
  font-size: 1.2rem;
  /* color: #fff; */
  font-weight: 600;
}

footer p #currYear {
  color: #ff817a;
  font-weight: 600;
}

@media (max-width: 300px) {
  .container{
    width: 250px;
  }

  .container input {
    padding: 20px 5px;
  }
}