:root {
  /* Brand Colors */
  --primary-green: #4A7C59;
  --secondary-green: #6B9E7A;
  --accent-orange: #F4A261;
  --dark-green: #2D5A3D;
  --light-green: #E8F5E9;

  /* Neutral Colors */
  --bg-light: #F8F9FA;
  --bg-white: #FFFFFF;
  --text-dark: #2C3E50;
  --text-medium: #5A6C7D;
  --text-light: #8B9AA8;
  --border-color: #E0E6ED;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, var(--primary-green) 0%, var(--secondary-green) 100%);
  --gradient-hero: linear-gradient(135deg, rgba(74, 124, 89, 0.95) 0%, rgba(45, 90, 61, 0.95) 100%);

  /* Shadows */
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.15);

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;

  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;

  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;

  /* Typography */
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-heading: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* Reset & Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  color: var(--text-dark);
  background-color: var(--bg-light);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Header */
.app-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  box-shadow: var(--shadow-sm);
  z-index: 1000;
  padding: var(--spacing-sm) 0;
  transition: all var(--transition-normal);
}

.header-content {
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-md);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.logo-img {
  width: 40px;
  height: 40px;
  object-fit: contain;
}

.logo-text {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-green);
}

.header-controls {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

.control-group {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.control-group label {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-medium);
  white-space: nowrap;
}

.header-select {
  padding: 0.5rem 0.75rem;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-sm);
  background: var(--bg-white);
  color: var(--text-dark);
  font-family: var(--font-body);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.header-select:hover {
  border-color: var(--primary-green);
}

.header-select:focus {
  outline: none;
  border-color: var(--primary-green);
  box-shadow: 0 0 0 3px rgba(74, 124, 89, 0.1);
}

/* Hero Section */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--gradient-hero), url('splash.png') center/cover;
  color: white;
  text-align: center;
  padding: var(--spacing-2xl) var(--spacing-md);
  margin-top: 72px;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: var(--gradient-hero);
  z-index: 1;
}

.hero-content {
  position: relative;
  z-index: 2;
  max-width: 800px;
  animation: fadeInUp 1s ease-out;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 800;
  margin-bottom: var(--spacing-md);
  line-height: 1.2;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.hero-subtitle {
  font-size: clamp(1.25rem, 3vw, 1.75rem);
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  opacity: 0.95;
}

.hero-description {
  font-size: clamp(1rem, 2vw, 1.125rem);
  line-height: 1.8;
  margin-bottom: var(--spacing-xl);
  opacity: 0.9;
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

.scroll-indicator {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-xs);
  color: white;
  text-decoration: none;
  font-weight: 500;
  transition: all var(--transition-normal);
  padding: var(--spacing-sm);
}

.scroll-indicator:hover {
  transform: translateY(5px);
}

.scroll-arrow {
  animation: bounce 2s infinite;
}

@keyframes bounce {

  0%,
  20%,
  50%,
  80%,
  100% {
    transform: translateY(0);
  }

  40% {
    transform: translateY(-10px);
  }

  60% {
    transform: translateY(-5px);
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Calculator Section */
.calculator {
  padding: var(--spacing-2xl) var(--spacing-md);
  background: var(--bg-light);
}

.container {
  max-width: 1200px;
  margin: 0 auto;
}

.calculator-form {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
}

.form-section {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.form-section:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
}

.section-title {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--primary-green);
  margin-bottom: var(--spacing-lg);
  padding-bottom: var(--spacing-sm);
  border-bottom: 3px solid var(--light-green);
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: var(--spacing-lg);
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.form-group label {
  font-weight: 600;
  color: var(--text-dark);
  font-size: 0.9375rem;
  display: flex;
  align-items: baseline;
  gap: var(--spacing-xs);
}

.param-description {
  font-family: var(--font-body);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-medium);
  margin-top: -2px;
  margin-bottom: 2px;
  line-height: 1.4;
}

.unit {
  font-weight: 400;
  color: var(--text-medium);
  font-size: 0.875rem;
}

.form-group input,
.form-group select {
  padding: 0.875rem 1rem;
  border: 2px solid var(--border-color);
  border-radius: var(--radius-sm);
  font-family: var(--font-body);
  font-size: 1rem;
  color: var(--text-dark);
  background: var(--bg-white);
  transition: all var(--transition-fast);
}

.form-group input:hover,
.form-group select:hover {
  border-color: var(--secondary-green);
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--primary-green);
  box-shadow: 0 0 0 4px rgba(74, 124, 89, 0.1);
}

.form-group input::placeholder {
  color: var(--text-light);
}

/* Calculate Button */
.form-actions {
  display: flex;
  justify-content: center;
  margin-top: var(--spacing-lg);
}

.btn-calculate {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: 1rem 3rem;
  background: var(--gradient-primary);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.btn-calculate::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.2) 0%, rgba(255, 255, 255, 0) 100%);
  opacity: 0;
  transition: opacity var(--transition-normal);
}

.btn-calculate:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-xl);
}

.btn-calculate:hover::before {
  opacity: 1;
}

.btn-calculate:active {
  transform: translateY(0);
}

.btn-calculate.calculating {
  pointer-events: none;
  opacity: 0.8;
}

.btn-icon {
  transition: transform var(--transition-normal);
}

.btn-calculate:hover .btn-icon {
  transform: translateX(4px);
}

/* Results Section */
.results {
  padding: var(--spacing-2xl) var(--spacing-md);
  background: linear-gradient(180deg, var(--bg-light) 0%, var(--light-green) 100%);
  animation: fadeIn var(--transition-slow);
}

@keyframes fadeIn {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

.results-title {
  font-family: var(--font-heading);
  font-size: 2.5rem;
  font-weight: 800;
  color: var(--primary-green);
  text-align: center;
  margin-bottom: var(--spacing-xl);
}

.comparison-table {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
  margin-bottom: var(--spacing-xl);
}

.table-responsive {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

thead {
  background: var(--gradient-primary);
  color: white;
}

th {
  padding: 1.25rem 1rem;
  text-align: left;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1rem;
}

.currency-header {
  display: block;
  font-size: 0.875rem;
  font-weight: 500;
  opacity: 0.9;
  margin-top: 0.25rem;
}

th:first-child {
  border-top-left-radius: var(--radius-md);
}

th:last-child {
  border-top-right-radius: var(--radius-md);
}

tbody tr {
  border-bottom: 1px solid var(--border-color);
  transition: background-color var(--transition-fast);
}

tbody tr:hover {
  background-color: var(--light-green);
}

tbody tr.total-row {
  background: var(--light-green);
  font-weight: 700;
  font-size: 1.125rem;
}

td {
  padding: 1.25rem 1rem;
  color: var(--text-dark);
}

/* Savings Summary */
.savings-summary {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-xl);
}

.savings-card {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  transition: all var(--transition-normal);
  border: 3px solid transparent;
}

.savings-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--accent-orange);
}

.savings-icon {
  font-size: 3rem;
  flex-shrink: 0;
}

.savings-content h3 {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-medium);
  margin-bottom: var(--spacing-xs);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.savings-amount {
  font-family: var(--font-heading);
  font-size: 2rem;
  font-weight: 800;
  color: var(--primary-green);
  line-height: 1;
}

/* Details Section */
.details-section {
  background: var(--bg-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
}

.details-title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--primary-green);
  margin-bottom: var(--spacing-lg);
}

.details-comparison {
  margin-bottom: var(--spacing-lg);
}

.details-table {
  width: 100%;
  border-collapse: collapse;
}

.details-table thead {
  background: var(--light-green);
}

.details-table th {
  padding: 1rem;
  text-align: left;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.9375rem;
  color: var(--primary-green);
  border-bottom: 2px solid var(--primary-green);
}

.details-table tbody tr {
  border-bottom: 1px solid var(--border-color);
}

.details-table tbody tr:last-child {
  border-bottom: none;
}

.details-table td {
  padding: 1rem;
  color: var(--text-dark);
  font-weight: 500;
}

.details-table td:first-child {
  font-weight: 600;
  color: var(--text-medium);
}

.details-table td:not(:first-child) {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  color: var(--primary-green);
  font-weight: 700;
}

.detail-single {
  padding-top: var(--spacing-lg);
  border-top: 2px solid var(--border-color);
}

.detail-item-single {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md);
  background: var(--light-green);
  border-radius: var(--radius-sm);
  border-left: 4px solid var(--accent-orange);
}

.detail-item-single .detail-label {
  font-weight: 600;
  color: var(--text-dark);
  font-size: 1rem;
}

.detail-item-single .detail-value {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--accent-orange);
}

/* Old detail-item styles removed, keeping for backwards compatibility if needed */
.details-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
}

.detail-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md);
  background: var(--light-green);
  border-radius: var(--radius-sm);
  border-left: 4px solid var(--primary-green);
}

.detail-label {
  font-weight: 600;
  color: var(--text-dark);
}

.detail-value {
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.125rem;
  color: var(--primary-green);
}

/* Footer */
.footer {
  background: var(--text-dark);
  color: white;
  padding: var(--spacing-2xl) var(--spacing-md) var(--spacing-lg);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-section h4 {
  font-family: var(--font-heading);
  font-weight: 700;
  margin-bottom: var(--spacing-md);
  color: var(--secondary-green);
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-md);
}

.footer-logo-img {
  width: 50px;
  height: 50px;
  object-fit: contain;
}

.footer-logo-text {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--secondary-green);
}

.footer-copyright {
  opacity: 0.8;
  font-size: 0.875rem;
}

.footer-link {
  display: block;
  color: rgba(255, 255, 255, 0.8);
  text-decoration: none;
  margin-bottom: var(--spacing-xs);
  transition: all var(--transition-fast);
}

.footer-link:hover {
  color: var(--secondary-green);
  transform: translateX(4px);
}

.footer-disclaimer {
  padding-top: var(--spacing-lg);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  text-align: center;
  opacity: 0.7;
  font-size: 0.875rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .header-content {
    flex-direction: column;
    gap: var(--spacing-sm);
  }

  .header-controls {
    flex-direction: column;
    width: 100%;
    gap: var(--spacing-sm);
  }

  .control-group {
    width: 100%;
    justify-content: space-between;
  }

  .header-select {
    flex: 1;
  }

  .hero {
    margin-top: 140px;
    min-height: calc(100vh - 140px);
  }

  .form-grid {
    grid-template-columns: 1fr;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .results-title {
    font-size: 2rem;
  }

  th,
  td {
    padding: 0.875rem 0.5rem;
    font-size: 0.875rem;
  }

  .savings-card {
    flex-direction: column;
    text-align: center;
  }

  .savings-amount {
    font-size: 1.75rem;
  }

  .footer-content {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .details-table th,
  .details-table td {
    padding: 0.75rem 0.5rem;
    font-size: 0.875rem;
  }

  .details-table td:not(:first-child) {
    font-size: 1rem;
  }

  .detail-item-single {
    flex-direction: column;
    gap: var(--spacing-xs);
    text-align: center;
  }
}

@media (min-width: 769px) and (max-width: 1024px) {
  .form-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

/* Loading State */
.loading {
  position: relative;
  pointer-events: none;
}

.loading::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(255, 255, 255, 0.8);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: inherit;
}

/* Smooth Transitions */
* {
  transition-property: background-color, border-color, color, fill, stroke, opacity, box-shadow, transform;
  transition-duration: var(--transition-fast);
  transition-timing-function: ease-in-out;
}

/* Accessibility */
:focus-visible {
  outline: 3px solid var(--accent-orange);
  outline-offset: 2px;
}

/* Print Styles */
@media print {

  .app-header,
  .hero,
  .calculator,
  .footer {
    display: none;
  }

  .results {
    display: block !important;
  }
}