/**
 * Виза в Азию (Индия, Вьетнам)
 * Core CSS: Variables, Reset, Typography, Grid & Base Layout
 */

:root {
  /* Colors */
  --color-bg: #f8fafc;
  --color-surface: #ffffff;
  --color-surface-soft: #f1f5f9;
  --color-surface-muted: #e2e8f0;
  
  --color-text-main: #0f172a;
  --color-text-secondary: #475569;
  --color-text-muted: #64748b;
  --color-text-light: #94a3b8;
  --color-text-inverse: #ffffff;

  /* Brand Accents */
  --color-primary: #0f172a;
  --color-primary-hover: #1e293b;
  --color-accent: #2563eb;
  --color-accent-hover: #1d4ed8;
  --color-accent-light: #eff6ff;
  --color-warm: #f97316;
  --color-warm-light: #fff7ed;
  --color-success: #16a34a;
  --color-success-light: #f0fdf4;
  
  /* Telegram & Social */
  --color-telegram: #229ed9;
  --color-telegram-hover: #1b86ba;
  --color-whatsapp: #25d366;
  --color-vk: #0077ff;

  /* Borders & Shadows */
  --border-color: #e2e8f0;
  --border-color-dark: #cbd5e1;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-xl: 24px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.09), 0 8px 10px -6px rgba(0, 0, 0, 0.04);
  --shadow-glow: 0 0 20px rgba(37, 99, 235, 0.15);

  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  --font-heading: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);

  /* Layout */
  --container-max: 1200px;
  --container-narrow: 840px;
  --header-height: 76px;
}

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

html {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text-main);
  background-color: var(--color-bg);
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

img, picture, svg, video {
  display: block;
  max-width: 100%;
  height: auto;
}

input, button, textarea, select {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: none;
  background: none;
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

ul, ol {
  list-style: none;
}

/* Accessible Focus Styles */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

/* Typography Helpers */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  color: var(--color-text-main);
  line-height: 1.25;
  font-weight: 700;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2rem, 4vw + 1rem, 3.25rem);
}

h2 {
  font-size: clamp(1.6rem, 2.5vw + 0.8rem, 2.35rem);
  margin-bottom: 0.75rem;
}

h3 {
  font-size: clamp(1.2rem, 1.5vw + 0.6rem, 1.5rem);
}

p {
  color: var(--color-text-secondary);
  margin-bottom: 1rem;
}

p:last-child {
  margin-bottom: 0;
}

.lead-text {
  font-size: 1.125rem;
  line-height: 1.7;
  color: var(--color-text-secondary);
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

.container-narrow {
  max-width: var(--container-narrow);
}

/* Section Spacing */
.section {
  padding-top: clamp(3.5rem, 6vw, 6rem);
  padding-bottom: clamp(3.5rem, 6vw, 6rem);
}

.section-alt {
  background-color: var(--color-surface);
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
}

.section-header {
  text-align: center;
  max-width: 680px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: clamp(2rem, 4vw, 3.5rem);
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.85rem;
  background-color: var(--color-accent-light);
  color: var(--color-accent);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  margin-bottom: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.section-tag.warm {
  background-color: var(--color-warm-light);
  color: var(--color-warm);
}

.section-tag.success {
  background-color: var(--color-success-light);
  color: var(--color-success);
}

.section-subtitle {
  font-size: 1.1rem;
  color: var(--color-text-muted);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
  padding: 0.85rem 1.65rem;
  font-size: 1rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  transition: all var(--transition-normal);
  white-space: nowrap;
  user-select: none;
}

.btn-sm {
  padding: 0.55rem 1.1rem;
  font-size: 0.875rem;
  border-radius: var(--radius-sm);
}

.btn-lg {
  padding: 1rem 2.2rem;
  font-size: 1.125rem;
  border-radius: var(--radius-lg);
}

.btn-primary {
  background-color: var(--color-primary);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-sm);
}

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

.btn-accent {
  background-color: var(--color-accent);
  color: var(--color-text-inverse);
  box-shadow: var(--shadow-sm);
}

.btn-accent:hover {
  background-color: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: var(--color-text-inverse);
}

.btn-telegram {
  background-color: var(--color-telegram);
  color: var(--color-text-inverse);
  box-shadow: 0 4px 12px rgba(34, 158, 217, 0.25);
}

.btn-telegram:hover {
  background-color: var(--color-telegram-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 16px rgba(34, 158, 217, 0.35);
  color: var(--color-text-inverse);
}

.btn-red {
  background-color: #dc2626;
  color: var(--color-text-inverse);
  box-shadow: 0 4px 14px rgba(220, 38, 38, 0.28);
}

.btn-red:hover {
  background-color: #b91c1c;
  transform: translateY(-2px);
  box-shadow: 0 6px 18px rgba(220, 38, 38, 0.38);
  color: var(--color-text-inverse);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-text-main);
  border: 1.5px solid var(--border-color-dark);
}

.btn-outline:hover {
  background-color: var(--color-surface);
  border-color: var(--color-text-main);
  transform: translateY(-2px);
}

.btn-icon {
  width: 1.25rem;
  height: 1.25rem;
  fill: currentColor;
  flex-shrink: 0;
}

/* Badges & Tags */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.25rem 0.65rem;
  font-size: 0.75rem;
  font-weight: 700;
  border-radius: var(--radius-full);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.badge-featured {
  background-color: #fef3c7;
  color: #b45309;
}

.badge-free {
  background-color: #dcfce7;
  color: #15803d;
}

/* Grid Layouts */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 2rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1.5rem;
}

@media (max-width: 992px) {
  .grid-3, .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
}

/* Utility classes */
.text-center { text-align: center; }
.text-accent { color: var(--color-accent); }
.text-warm { color: var(--color-warm); }
.text-muted { color: var(--color-text-muted); }
.font-bold { font-weight: 700; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }