/**
 * AI Gift Finder - Mobile-First Styles
 * Design System: Modern, Clean, Premium UX
 */

/* ==================== CSS Reset & Base ==================== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* Primary Colors (Trust & Intelligence) */
  --color-primary: #6366F1;
  --color-primary-dark: #4F46E5;
  --color-primary-light: #818CF8;
  --color-primary-glow: rgba(99, 102, 241, 0.15);

  /* Secondary Colors (Joy & Celebration) */
  --color-secondary: #EC4899;
  --color-secondary-light: #F9A8D4;
  --color-accent-warm: #F59E0B;
  --color-accent-cool: #10B981;

  /* Semantic Colors */
  --color-success: #10B981;
  --color-warning: #F59E0B;
  --color-danger: #EF4444;
  --color-info: #3B82F6;

  /* Grays (Hierarchy & Readability) */
  --color-gray-50: #F9FAFB;
  --color-gray-100: #F3F4F6;
  --color-gray-200: #E5E7EB;
  --color-gray-300: #D1D5DB;
  --color-gray-400: #9CA3AF;
  --color-gray-500: #6B7280;
  --color-gray-600: #4B5563;
  --color-gray-700: #374151;
  --color-gray-800: #1F2937;
  --color-gray-900: #111827;

  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #6366F1 0%, #4F46E5 100%);
  --gradient-warm: linear-gradient(135deg, #F59E0B 0%, #EC4899 100%);
  --gradient-success: linear-gradient(135deg, #10B981 0%, #059669 100%);
  --gradient-shimmer: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  
  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Hiragino Sans',
    'Hiragino Kaku Gothic ProN', 'Noto Sans JP', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  
  /* Spacing */
  --spacing-1: 0.25rem;
  --spacing-2: 0.5rem;
  --spacing-3: 0.75rem;
  --spacing-4: 1rem;
  --spacing-5: 1.25rem;
  --spacing-6: 1.5rem;
  --spacing-8: 2rem;
  --spacing-10: 2.5rem;
  --spacing-12: 3rem;
  --spacing-16: 4rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 300ms cubic-bezier(0.4, 0, 0.2, 1);
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  margin: 0;
  padding: 0;
  width: 100%;
  overflow-x: hidden;
}

body {
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: 1.6;
  color: var(--color-gray-900);
  /* Smooth gradient transition from hero section to content area */
  background: linear-gradient(
    180deg,
    rgba(99, 102, 241, 0.03) 0%,
    rgba(236, 72, 153, 0.02) 30%,
    var(--color-gray-50) 70%
  );
  min-height: 100vh;
  margin: 0;
  padding: 0;
  width: 100%;
  overflow-x: hidden;
}

#app {
  margin: 0;
  padding: 0;
  width: 100%;
  overflow-x: hidden;
}

/* ==================== Layout ==================== */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-4);
}

@media (min-width: 768px) {
  .container {
    padding: 0 var(--spacing-6);
  }
}

/* ==================== Header ==================== */
.header {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: white;
  padding: var(--spacing-6) 0;
  text-align: center;
  box-shadow: var(--shadow-md);
}

.logo {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--spacing-2);
}

.tagline {
  font-size: var(--font-size-sm);
  opacity: 0.9;
}

/* ==================== Main ==================== */
.main {
  padding: var(--spacing-8) 0;
  min-height: calc(100vh - 200px);
}

/* ==================== Screens ==================== */
.screen {
  display: none;
  animation: fadeIn var(--transition-slow);
}

.screen.active {
  display: block;
}

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

/* ==================== Hero Section ==================== */
/* Hero base styles moved to enhanced.css for full-width layout */

.hero-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--spacing-6);
  color: var(--color-gray-900);
}

.hero-description {
  font-size: var(--font-size-lg);
  color: var(--color-gray-600);
  margin-bottom: var(--spacing-8);
  line-height: 1.8;
}

/* ==================== Features ==================== */
.features {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-6);
  margin-top: var(--spacing-12);
}

@media (min-width: 768px) {
  .features {
    grid-template-columns: repeat(3, 1fr);
  }
}

.feature {
  text-align: center;
  padding: var(--spacing-6);
  background: white;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.feature:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.feature-icon {
  font-size: var(--font-size-4xl);
  margin-bottom: var(--spacing-4);
}

.feature-title {
  font-size: var(--font-size-xl);
  font-weight: 600;
  margin-bottom: var(--spacing-2);
  color: var(--color-gray-900);
}

.feature-description {
  font-size: var(--font-size-sm);
  color: var(--color-gray-600);
}

/* ==================== Buttons ==================== */
.button {
  display: inline-block;
  padding: var(--spacing-4) var(--spacing-8);
  font-size: var(--font-size-lg);
  font-weight: 600;
  text-align: center;
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  font-family: inherit;
  width: 100%;
}

@media (min-width: 768px) {
  .button {
    width: auto;
    min-width: 200px;
  }
}

.button-primary {
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
  color: white;
  box-shadow: var(--shadow-md);
}

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

.button-primary:active {
  transform: translateY(0);
}

.button-secondary {
  background: white;
  color: var(--color-primary);
  border: 2px solid var(--color-primary);
}

.button-secondary:hover {
  background: var(--color-gray-50);
}

/* ==================== Progress Bar ==================== */
.progress-container {
  margin-bottom: var(--spacing-8);
}

.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--color-gray-200);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--spacing-3);
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary) 0%, var(--color-secondary) 100%);
  border-radius: var(--radius-full);
  transition: width var(--transition-slow);
}

.progress-text {
  text-align: center;
  font-size: var(--font-size-sm);
  color: var(--color-gray-600);
  font-weight: 600;
}

/* ==================== Question Card ==================== */
.question-card {
  background: white;
  border-radius: var(--radius-xl);
  padding: var(--spacing-8);
  box-shadow: var(--shadow-lg);
  max-width: 600px;
  margin: 0 auto;
}

.question-title {
  font-size: var(--font-size-2xl);
  font-weight: 700;
  margin-bottom: var(--spacing-6);
  color: var(--color-gray-900);
  line-height: 1.4;
}

.choice-options {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-3);
}

.choice-option {
  padding: var(--spacing-4);
  background: var(--color-gray-50);
  border: 2px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  font-size: var(--font-size-base);
  font-weight: 500;
  text-align: left;
}

.choice-option:hover {
  background: var(--color-gray-100);
  border-color: var(--color-primary-light);
}

.choice-option.selected {
  background: var(--color-primary-light);
  border-color: var(--color-primary);
  color: white;
}

/* ==================== Text Input ==================== */
.text-input {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-2);
}

.textarea {
  width: 100%;
  padding: var(--spacing-4);
  font-size: var(--font-size-base);
  font-family: inherit;
  border: 2px solid var(--color-gray-200);
  border-radius: var(--radius-lg);
  resize: vertical;
  min-height: 120px;
  transition: border-color var(--transition-base);
}

.textarea:focus {
  outline: none;
  border-color: var(--color-primary);
}

.char-counter {
  text-align: right;
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
  padding: 0 var(--spacing-2);
  font-family: monospace;
  transition: color var(--transition-base);
}

/* ==================== Loading ==================== */
.loading {
  text-align: center;
  padding: var(--spacing-16) 0;
}

.spinner {
  width: 60px;
  height: 60px;
  margin: 0 auto var(--spacing-6);
  border: 4px solid var(--color-gray-200);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.loading-text {
  font-size: var(--font-size-lg);
  color: var(--color-gray-600);
  line-height: 1.8;
}

/* ==================== Results ==================== */
.results-header {
  text-align: center;
  margin-bottom: var(--spacing-8);
}

.results-title {
  font-size: var(--font-size-3xl);
  font-weight: 700;
  margin-bottom: var(--spacing-3);
}

.results-count {
  font-size: var(--font-size-base);
  color: var(--color-gray-600);
}

.products-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-4);
  margin-bottom: var(--spacing-12);
}

@media (min-width: 640px) {
  .products-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-4);
  }
}

@media (min-width: 1024px) {
  .products-grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-4);
  }
}

@media (min-width: 1280px) {
  .products-grid {
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-3);
  }
}

@media (min-width: 1536px) {
  .products-grid {
    grid-template-columns: repeat(6, 1fr);
    gap: var(--spacing-3);
  }
}

.product-card {
  background: white;
  border-radius: var(--radius-xl);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
  cursor: pointer;
}

.product-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.product-image {
  width: 100%;
  aspect-ratio: 1 / 1;
  object-fit: cover;
}

.product-info {
  padding: var(--spacing-3);
}

.product-name {
  font-size: var(--font-size-sm);
  font-weight: 600;
  margin-bottom: var(--spacing-1);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  line-height: 1.4;
}

.product-shop {
  font-size: var(--font-size-xs);
  color: var(--color-gray-600);
  margin-bottom: var(--spacing-2);
}

.product-price {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--spacing-2);
}

.product-rating {
  display: flex;
  align-items: center;
  gap: var(--spacing-1);
  font-size: var(--font-size-xs);
}

.product-stars {
  color: var(--color-warning);
}

.product-review-count {
  color: var(--color-gray-500);
}

.product-score {
  display: inline-block;
  margin-top: var(--spacing-2);
  padding: var(--spacing-1) var(--spacing-3);
  background: var(--color-success);
  color: white;
  font-size: var(--font-size-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
}

/* ==================== Results Actions ==================== */
.results-actions {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-4);
  margin-top: var(--spacing-8);
  align-items: center;
}

@media (min-width: 768px) {
  .results-actions {
    flex-direction: row;
    justify-content: center;
  }
}

/* ==================== Footer ==================== */
.footer {
  background: var(--color-gray-900);
  color: var(--color-gray-300);
  padding: var(--spacing-16) 0 var(--spacing-8);
  margin-top: var(--spacing-20);
  border-top: 1px solid var(--color-gray-800);
}

.footer-content {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-10);
  margin-bottom: var(--spacing-12);
}

.footer-section {
  text-align: left;
}

.footer-title {
  font-size: var(--font-size-lg);
  font-weight: 700;
  color: var(--color-white);
  margin-bottom: var(--spacing-4);
}

.footer-title-sub {
  margin-top: var(--spacing-6);
  font-size: var(--font-size-base);
}

.footer-description {
  font-size: var(--font-size-sm);
  line-height: 1.6;
  margin-bottom: var(--spacing-3);
  color: var(--color-gray-400);
}

.footer-operator {
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
}

.footer-operator a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
  transition: color var(--transition-base);
}

.footer-operator a:hover {
  color: var(--color-primary-light);
  text-decoration: underline;
}

.footer-links {
  list-style: none;
  padding: 0;
  margin: 0;
}

.footer-links li {
  margin-bottom: var(--spacing-2);
}

.footer-links a {
  color: var(--color-gray-400);
  text-decoration: none;
  font-size: var(--font-size-sm);
  transition: color var(--transition-base);
  display: inline-block;
}

.footer-links a:hover {
  color: var(--color-white);
}

.footer-disclosure {
  background: var(--color-gray-800);
  padding: var(--spacing-6);
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-8);
}

.footer-disclosure p {
  font-size: var(--font-size-xs);
  line-height: 1.6;
  color: var(--color-gray-400);
  margin: 0;
}

.footer-copyright {
  text-align: center;
  padding-top: var(--spacing-6);
  border-top: 1px solid var(--color-gray-800);
}

.footer-copyright p {
  font-size: var(--font-size-sm);
  color: var(--color-gray-500);
  margin: var(--spacing-2) 0;
}

.footer-powered {
  font-size: var(--font-size-xs);
  color: var(--color-gray-600);
}

@media (min-width: 768px) {
  .footer-content {
    grid-template-columns: repeat(3, 1fr);
  }
  
  .footer-section:first-child {
    grid-column: span 1;
  }
}