:root {
  --primary-font: "Fredoka One", cursive;
  --primary-color: #ff7a00;
  --primary-color-light: #fff2e5;
  --secondary-color: #000000;
  --tertiary-color: #ffffff;
}

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

*:focus {
  outline: none;
}

html {
  font-size: 62.5%;
}

body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  font-family: var(--primary-font);
  background-color: var(--primary-color-light);
  min-height: 100vh;
}

h1 {
  position: absolute;
  left: -10000px;
  width: 1px;
  height: 1px;
  top: auto;
  overflow: hidden;
}

.calculator-container {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 2rem;
  background-color: var(--primary-color-light);
  border: 10px solid var(--secondary-color);
  border-radius: 10px;
  padding: 3rem;
  min-width: 30vw;
  max-width: 90vw;
}

.display {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-end;
  text-align: right;
  background-color: var(--secondary-color);
  width: 100%;
  padding: 2rem;
  font-weight: 400;
}

.user-input {
  font-size: 2rem;
  color: var(--tertiary-color);
}

.result {
  font-size: 4.5rem;
  color: var(--primary-color);
}

.buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  grid-template-rows: repeat(5, 1fr);
  gap: 2rem;
  width: 100%;
}

button {
  background-color: var(--tertiary-color);
  padding: 1.5rem;
  border: none;
  border-radius: 10px;
  font-family: var(--primary-font);
  font-weight: 400;
  text-align: center;
  font-size: 2.8rem;
  cursor: pointer;
}

button:hover,
button:focus {
  background-color: rgba(0, 0, 0, 0.1);
}

.ac {
  grid-column: 1 / span 2;
  color: var(--primary-color);
}

.c {
  color: var(--primary-color);
  grid-column: 3 / span 2;
}

.action {
  color: var(--primary-color);
}

.equal-to {
  background-color: var(--primary-color);
  color: var(--tertiary-color);
  padding-bottom: 2.5rem;
}

.equal-to:hover, .equal-to:focus {
  background-color: rgb(12, 212, 12);
}

footer {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

footer p {
  font-size: 1.8rem;
  font-weight: 400;
  text-align: center;
}

footer p a {
  color: var(--primary-color);
  text-decoration: none;
}

footer p a:hover,
footer p a:focus {
  color: var(--secondary-color);
}

@media screen and (max-width: 76.8rem) {
  .calculator-container {
    width: 90vw;
  }
}