:root {
  --cal-button-bg: #630000;
  --cal-button-hover: #222263;
  --cal-accent-color: #8b0000;
  --cal-equal-color: #006300;
  --cal-font-family: "Segoe UI", sans-serif;
  --cal-ecran: #330008;
  --cal-fond: #220008;
}

* {
  box-sizing: border-box;
}

body {
  font-family: var(--cal-font-family);

  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 0;
  padding: 20px;
}

.calculator {
  background: --var(--cal-fond);
  border-radius: 20px;
  padding: 14px;
  width: 280px;
  border-radius: 10px;
  box-shadow: 0 0 20px var(--rouge-brun);
}

.display {
  background: var(--cal-ecran);
  padding: 14px;
  font-size: 1.3em;
  text-align: right;
  border-radius: 10px;
  margin-bottom: 14px;
  overflow-x: auto;
  min-height: 40px;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 6px;
}

button {
  padding: 10px;
  font-size: 1em;
  border: none;
  border-radius: 10px;
  background: var(--cal-button-bg);
  color: var(--cal-text-color);
  cursor: pointer;
  transition: background 0.2s;
  height: 45px;
  width: 45px;
}

button:hover {
  background: var(--cal-button-hover);
}

.equal {
  background: var(--cal-equal-color);
  font-weight: bold;
}

.clear {
  background: var(--cal-accent-color);
}