/* CSS Variables for Theme Management */
:root {
  --primary-color: #1A535C;
  --secondary-color: #4ECDC4;
  --background-color: #F7FFF7;
  --accent-color: #FF6B6B;
  --warning-color: #FFE66D;
  --text-color: #1A535C;
  --text-secondary: #666;
  --border-color: #e0e0e0;
  --shadow: 0 2px 10px rgba(26, 83, 92, 0.1);
  --shadow-hover: 0 4px 20px rgba(26, 83, 92, 0.15);
  --border-radius: 8px;
  --transition: all 0.3s ease;
}

[data-theme="dark"] {
  --primary-color: #4ECDC4;
  --secondary-color: #1A535C;
  --background-color: #1a1a1a;
  --accent-color: #FF6B6B;
  --warning-color: #FFE66D;
  --text-color: #F7FFF7;
  --text-secondary: #ccc;
  --border-color: #333;
  --shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
  --shadow-hover: 0 4px 20px rgba(0, 0, 0, 0.4);
}

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

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--background-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: var(--transition);
}

/* Layout */
.app-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header__content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.header__title {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.5px;
}

.header__controls {
  display: flex;
  gap: 0.5rem;
}

/* Navigation */
.nav {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(10px);
}

.nav__list {
  display: flex;
  list-style: none;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  overflow-x: auto;
}

.nav__link {
  background: none;
  border: none;
  color: white;
  padding: 1rem 1.5rem;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  font-size: 0.9rem;
  font-weight: 500;
}

.nav__link:hover,
.nav__link--active {
  background: rgba(255, 255, 255, 0.2);
  border-bottom: 3px solid var(--warning-color);
}

/* Main Content */
.main {
  flex: 1;
  padding: 2rem;
  max-width: 1200px;
  margin: 0 auto;
  width: 100%;
}

/* Tab Content */
.tab-content {
  display: none;
  animation: fadeIn 0.3s ease;
}

.tab-content--active {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Calculator */
.calculator {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  padding: 2rem;
  margin-bottom: 2rem;
}

.calculator__header {
  margin-bottom: 2rem;
}

.calculator__title {
  font-size: 1.8rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.calculator__actions {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1rem;
}

/* Ingredient Search */
.ingredient-search {
  margin-bottom: 2rem;
}

.search-container {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
}

.search-results {
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  max-height: 200px;
  overflow-y: auto;
  display: none;
}

.search-results--visible {
  display: block;
}

.search-result {
  padding: 0.75rem 1rem;
  cursor: pointer;
  border-bottom: 1px solid var(--border-color);
  transition: var(--transition);
}

.search-result:hover {
  background: var(--secondary-color);
  color: white;
}

.search-result:last-child {
  border-bottom: none;
}

/* Ingredients List */
.ingredients-list {
  margin-bottom: 2rem;
}

.ingredients-list__title {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  color: var(--primary-color);
}

.ingredient-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem;
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  margin-bottom: 0.5rem;
  transition: var(--transition);
}

.ingredient-item:hover {
  box-shadow: var(--shadow-hover);
}

.ingredient-info {
  flex: 1;
}

.ingredient-name {
  font-weight: 600;
  margin-bottom: 0.25rem;
}

.ingredient-calories {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.ingredient-controls {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.quantity-input {
  width: 80px;
  text-align: center;
}

/* Nutrition Summary */
.nutrition-summary {
  background: linear-gradient(135deg, var(--secondary-color), var(--primary-color));
  color: white;
  padding: 2rem;
  border-radius: var(--border-radius);
  margin-bottom: 2rem;
}

.nutrition-summary__title {
  font-size: 1.3rem;
  margin-bottom: 1rem;
  text-align: center;
}

.nutrition-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 1rem;
}

.nutrition-card {
  background: rgba(255, 255, 255, 0.1);
  padding: 1rem;
  border-radius: var(--border-radius);
  text-align: center;
  backdrop-filter: blur(10px);
}

.nutrition-card__label {
  display: block;
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
  opacity: 0.9;
}

.nutrition-card__value {
  display: block;
  font-size: 1.5rem;
  font-weight: 700;
}

/* Buttons */
.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: var(--border-radius);
  cursor: pointer;
  font-weight: 600;
  transition: var(--transition);
  text-decoration: none;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
}

.btn--primary {
  background: var(--primary-color);
  color: white;
}

.btn--primary:hover {
  background: var(--secondary-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.btn--secondary {
  background: var(--secondary-color);
  color: white;
}

.btn--secondary:hover {
  background: var(--primary-color);
  transform: translateY(-2px);
}

.btn--danger {
  background: var(--accent-color);
  color: white;
}

.btn--danger:hover {
  background: #e55555;
  transform: translateY(-2px);
}

.btn--icon {
  padding: 0.5rem;
  border-radius: 50%;
  width: 40px;
  height: 40px;
}

.btn--small {
  padding: 0.5rem 1rem;
  font-size: 0.8rem;
}

/* Form Elements */
.input {
  padding: 0.75rem;
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: var(--transition);
  background: var(--background-color);
  color: var(--text-color);
}

.input:focus {
  outline: none;
  border-color: var(--secondary-color);
  box-shadow: 0 0 0 3px rgba(78, 205, 196, 0.1);
}

.label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 600;
  color: var(--text-color);
}

.form-group {
  margin-bottom: 1rem;
}

.form-actions {
  display: flex;
  gap: 1rem;
  justify-content: flex-end;
  margin-top: 2rem;
}

/* Recipe Cards */
.recipe-card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
  margin-bottom: 1rem;
  transition: var(--transition);
  cursor: pointer;
}

.recipe-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-hover);
}

.recipe-card__header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.recipe-card__title {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--primary-color);
}

.recipe-card__actions {
  display: flex;
  gap: 0.5rem;
}

.recipe-card__info {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: 1rem;
  margin-bottom: 1rem;
}

.recipe-info-item {
  text-align: center;
}

.recipe-info-label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.recipe-info-value {
  display: block;
  font-weight: 600;
  color: var(--primary-color);
}

/* Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: none;
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.modal--visible {
  display: flex;
}

.modal__content {
  background: var(--background-color);
  border-radius: var(--border-radius);
  max-width: 500px;
  width: 90%;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow-hover);
}

.modal__header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.modal__title {
  font-size: 1.3rem;
  color: var(--primary-color);
}

.modal__close {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-secondary);
}

.modal__body {
  padding: 1.5rem;
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  top: 1rem;
  right: 1rem;
  z-index: 1100;
}

.toast {
  background: var(--primary-color);
  color: white;
  padding: 1rem 1.5rem;
  border-radius: var(--border-radius);
  margin-bottom: 0.5rem;
  box-shadow: var(--shadow);
  animation: slideIn 0.3s ease;
  max-width: 300px;
}

.toast--success {
  background: #4CAF50;
}

.toast--error {
  background: var(--accent-color);
}

.toast--warning {
  background: var(--warning-color);
  color: var(--text-color);
}

@keyframes slideIn {
  from { transform: translateX(100%); opacity: 0; }
  to { transform: translateX(0); opacity: 1; }
}

/* Goals and Progress */
.goal-setting {
  background: white;
  padding: 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  margin-bottom: 2rem;
}

.progress-card {
  background: white;
  padding: 2rem;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  text-align: center;
}

.progress-bar {
  width: 100%;
  height: 20px;
  background: var(--border-color);
  border-radius: 10px;
  overflow: hidden;
  margin: 1rem 0;
}

.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--secondary-color), var(--primary-color));
  border-radius: 10px;
  transition: width 0.3s ease;
  width: 0%;
}

/* Achievements */
.achievement-card {
  background: white;
  border-radius: var(--border-radius);
  box-shadow: var(--shadow);
  padding: 1.5rem;
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.achievement-card--unlocked {
  background: linear-gradient(135deg, var(--warning-color), #ffd700);
}

.achievement-icon {
  font-size: 2rem;
  width: 60px;
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--background-color);
  border-radius: 50%;
}

.achievement-info {
  flex: 1;
}

.achievement-title {
  font-weight: 600;
  margin-bottom: 0.25rem;
  color: var(--primary-color);
}

.achievement-description {
  font-size: 0.9rem;
  color: var(--text-secondary);
}

/* Empty State */
.empty-state {
  text-align: center;
  color: var(--text-secondary);
  font-style: italic;
  padding: 2rem;
}

/* Footer */
.footer {
  background: var(--primary-color);
  color: white;
  text-align: center;
  padding: 1rem;
  margin-top: auto;
}

.footer__text {
  font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 768px) {
  .header__content {
    padding: 1rem;
  }
  
  .header__title {
    font-size: 1.5rem;
  }
  
  .main {
    padding: 1rem;
  }
  
  .calculator {
    padding: 1rem;
  }
  
  .calculator__actions {
    grid-template-columns: 1fr;
  }
  
  .search-container {
    flex-direction: column;
  }
  
  .ingredient-item {
    flex-direction: column;
    align-items: stretch;
    gap: 1rem;
  }
  
  .ingredient-controls {
    justify-content: space-between;
  }
  
  .nutrition-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .nav__list {
    padding: 0 1rem;
  }
  
  .nav__link {
    padding: 0.75rem 1rem;
  }
  
  .recipe-card__header {
    flex-direction: column;
    gap: 1rem;
  }
  
  .recipe-card__actions {
    align-self: stretch;
    justify-content: space-between;
  }
  
  .form-actions {
    flex-direction: column;
  }
  
  .toast-container {
    left: 1rem;
    right: 1rem;
  }
  
  .toast {
    max-width: none;
  }
}

@media (max-width: 480px) {
  .nutrition-grid {
    grid-template-columns: 1fr;
  }
  
  .recipe-card__info {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .modal__content {
    width: 95%;
  }
  
  .achievement-card {
    flex-direction: column;
    text-align: center;
  }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Focus styles for better accessibility */
button:focus,
input:focus,
.nav__link:focus {
  outline: 2px solid var(--secondary-color);
  outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  :root {
    --shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
    --border-color: #000;
  }
}

/* Print styles */
@media print {
  .header,
  .footer,
  .btn,
  .modal {
    display: none !important;
  }
  
  .main {
    padding: 0;
    max-width: none;
  }
  
  .calculator,
  .recipe-card {
    box-shadow: none;
    border: 1px solid #000;
  }
}