body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  font-family:
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    Oxygen,
    Ubuntu,
    Cantarell,
    "Open Sans",
    "Helvetica Neue",
    sans-serif;
  background: linear-gradient(135deg, #fdf7f5, #dfcdc5);
}

.calculator {
  background-color: #262220;
  padding: 16px;
  border-radius: 16px;
  box-shadow: 0 16px 40px rgba(0, 0, 0, 0.7);
  max-width: 340px;
  width: 100%;
  margin: 0 16px;
  box-sizing: border-box;
}

.ecran {
  background-color: #d3bcb3;
  color: #262220;
  min-height: 60px;
  border-radius: 8px;
  padding: 10px 12px;
  margin-bottom: 12px;
  font-size: 1.6rem;
  text-align: right;
  display: flex;
  align-items: center;
  justify-content: flex-end;
  box-sizing: border-box;
  word-wrap: break-word;
}

.buttons {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 8px;
}

.btn {
  border: none;
  border-radius: 999px;
  padding: 14px 0;
  font-size: 1.1rem;
  cursor: pointer;
  color: #d4b3a5;
  transition:
    background-color 0.15s ease,
    transform 0.1s ease,
    box-shadow 0.15s ease;
}

.btn:not(.equal-btn):not(.clear-btn) {
  background-color: #493e3a;
}

.btn[data-value="/"],
.btn[data-value="*"],
.btn[data-value="-"],
.btn[data-value="+"] {
  background-color: #3b3330 !important;
  color: #ad7f58;
}

.equal-btn {
  background-color: #0d141f;
  color: #d4b3a5;
}

.clear-btn {
  background-color: #181118;
  color: #d4b3a5;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 10px rgba(0, 0, 0, 0.4);
}

.btn:active {
  transform: translateY(0);
  box-shadow: none;
}

@media (max-width: 480px) {
  .ecran {
    font-size: 1.4rem;
    padding: 8px 10px;
  }

  .btn {
    padding: 12px 0;
    font-size: 1rem;
  }
}