:root {
  --accent: #2980b9;
  --accent-light: #3498db;
  --gray-light: #fafafa;
  --gray-dark: #333;
  --border: #ddd;
  --input-border: #ccc;
  --success: #27ae60;
  --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  --radius: 12px;
}

* {
  box-sizing: border-box;
}

body {
  font-family: "Segoe UI", sans-serif;
  padding: 40px 16px;
  margin: 0 auto;
  max-width: 720px;
  background-color: #f9f9f9;
  color: var(--gray-dark);
}

h2 {
  text-align: center;
  color: #2c3e50;
  margin-bottom: 24px;
}

.logo-container {
  text-align: center;
  margin-bottom: 24px;
}

.logo-animated {
  opacity: 0;
  transform: translateY(-10px) scale(0.95);
  animation: fadeSlideIn 0.8s ease-out forwards;
  max-width: 100%;
  height: auto;
}

@keyframes fadeSlideIn {
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

.calculator-card {
  background: white;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 32px;
}

.form-group {
  position: relative;
  margin-bottom: 22px;
}

.form-group input[type="number"] {
  width: 100%;
  padding: 14px 12px;
  font-size: 15px;
  border: 1px solid var(--input-border);
  border-radius: 6px;
  background-color: var(--gray-light);
}

.form-group label {
  position: absolute;
  top: 14px;
  left: 12px;
  font-size: 14px;
  color: #666;
  background: white;
  padding: 0 4px;
  transition: 0.2s ease;
  pointer-events: none;
}

.form-group input:focus + label,
.form-group input:not(:placeholder-shown) + label {
  top: -10px;
  font-size: 12px;
  color: var(--accent);
}

/* Reduce gap between radio groups */
fieldset {
  border: none;
  margin: 12px 0 20px; /* reduced top and bottom */
  padding: 0;
}

/* Match legend text color and style with input labels */
legend {
  font-weight: 500;
  margin-bottom: 8px;
  font-size: 14px;
  color: #3498db;
}

/* Radio group labels styling */
fieldset label {
  font-size: 14px;
  margin-right: 20px;
  color: #666;
  cursor: pointer;
}

/* Add similar outline style on radio inputs when focused or checked */
input[type="radio"] {
  margin-right: 6px;
  outline-offset: 2px;
  outline: none;
  cursor: pointer;
  vertical-align: middle;
  width: 16px;
  height: 16px;
  position: relative;
  appearance: none;
  border: 1.5px solid var(--input-border);
  border-radius: 50%;
  background-color: var(--gray-light);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input[type="radio"]:focus-visible {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

input[type="radio"]:checked {
  background-color: var(--accent);
  border-color: var(--accent);
}

input[type="radio"]:checked::after {
  content: "";
  position: absolute;
  top: 4px;
  left: 4px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: white;
}

/* Button */
button {
  background-color: var(--accent);
  color: white;
  border: none;
  padding: 14px;
  font-size: 16px;
  border-radius: 6px;
  cursor: pointer;
  width: 100%;
  transition: background-color 0.3s, transform 0.2s;
}

button:hover {
  background-color: var(--accent-light);
  transform: scale(1.02);
}

.result {
  display: none;
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.5s ease, transform 0.5s ease;
  background: white;
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  margin-top: 32px;
  overflow: hidden;
}

.result.show {
  display: block;
  opacity: 1;
  transform: translateY(0);
}

.result-header {
  background: var(--accent);
  color: white;
  padding: 18px;
  text-align: center;
  font-size: 18px;
  font-weight: bold;
}

.result-body {
  padding: 24px;
}

.result-line,
.result-total {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin: 10px 0;
}

.result-line {
  border-bottom: 1px dashed #eee;
  padding-bottom: 6px;
  font-size: 15px;
}

.result-total {
  font-size: 16px;
  font-weight: bold;
  margin-top: 20px;
  color: var(--success);
  border-top: 2px solid var(--accent);
  padding-top: 10px;
}

.result-logo {
  display: block;
  max-width: 140px;
  margin: 20px auto 10px;
  opacity: 0.95;
}

/* Optional PWA Modal styling (unchanged) */
#pwaModal {
  display: none;
  position: fixed;
  z-index: 1000;
  top: 0; left: 0;
  width: 100vw; height: 100vh;
  background: rgba(0, 0, 0, 0.5);
  justify-content: center;
  align-items: center;
}

#pwaModalContent {
  background: #fff;
  padding: 20px;
  border-radius: 10px;
  max-width: 400px;
  text-align: left;
  box-shadow: 0 2px 10px rgba(0,0,0,0.3);
}

#pwaModalContent h3 {
  margin-top: 0;
  color: var(--accent);
}

#pwaModalContent button {
  background: var(--accent);
  color: #fff;
  padding: 10px 16px;
  border: none;
  border-radius: 6px;
  width: 100%;
  cursor: pointer;
}

#installIcon {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background: var(--accent);
  color: white;
  padding: 10px 14px;
  border-radius: 50%;
  font-size: 20px;
  box-shadow: var(--shadow);
  cursor: pointer;
  z-index: 999;
}

input.error {
  border: 2px solid red;
}

.error-message {
  color: red;
  font-size: 0.875rem;
  margin-top: 4px;
}