* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background: #f4f6f8;
  color: #1f2937;
}

.container {
  width: 90%;
  max-width: 600px;
  margin: 80px auto;
}

h1 {
  text-align: center;
}

.subtitle {
  text-align: center;
  color: #6b7280;
}

.calculator {
  background: white;
  padding: 30px;
  border-radius: 16px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.08);
}

label {
  display: block;
  margin-bottom: 8px;
  font-weight: bold;
}

input {
  width: 100%;
  padding: 12px;
  margin-bottom: 18px;
}

button {
  width: 100%;
  padding: 13px;
  border: none;
  border-radius: 8px;
  background: #2563eb;
  color: white;
  font-size: 16px;
  cursor: pointer;
}

.result {
  margin-top: 20px;
  padding: 15px;
  background: #f3f4f6;
  border-radius: 8px;
  text-align: center;
}

/* Calculator selection */

.calculator-list {
   display: grid;
  gap: 15px;
    margin-top: 25px;
}

.calculator-card {
  width: 100%;
  padding: 20px;
  border: none;
  border-radius: 12px;
  background: white;
  color: #1f2937;
  font-size: 18px;
  font-weight: bold;
  text-align: left;
  cursor: pointer;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.08);
}

.calculator-card:hover {
    transform: translateY(-2px);
}

/* Hide calculators until selected */

.hidden {
    display: none;
}

/* Back button */

.back-button {
    width: auto;
    padding: 8px 14px;
      margin-bottom: 15px;
       background: #e5e7eb;
         color: #1f2937;
  font-size: 14px;
} 



/* Dropdown styling */

select {
  width: 100%;
padding: 12px;
 margin-bottom: 18px;
  font-size: 16px;
}

/* colour change */

body {
  background: #FFF9F0;
}

button {
 background: #FF6B35;
}

.calculator-card {
 background: #FFF9F0;
  border: 1px solid #FFE0D2;
}

.back-button {
 background: #FFE0D2;
   color: #1f2937;
}