/*
 * GF PriceChecker - Base Styles
 * Following DESIGN-SYSTEM.md guidelines
 * Anti-AI aesthetic: solid colors, generous whitespace, clean typography
 */

:root {
  /* ========================================
     COLORS - Solid only, no gradients
     ======================================== */

  /* Primary Brand Color */
  --primary-blue: #0000FF;

  /* Neutrals */
  --black: #000000;
  --white: #FFFFFF;
  --light-gray: #F5F5F5;
  --medium-gray: #808080;
  --dark-gray: #333333;

  /* Semantic Colors (use sparingly) */
  --success: #00C853;
  --warning: #FF6D00;
  --error: #D50000;

  /* ========================================
     SPACING SYSTEM - 8px base
     ======================================== */
  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 32px;
  --space-2xl: 48px;
  --space-3xl: 64px;

  /* ========================================
     TYPOGRAPHY
     ======================================== */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  /* Type Scale */
  --text-xs: 0.75rem;    /* 12px */
  --text-sm: 0.875rem;   /* 14px */
  --text-md: 1rem;       /* 16px - body */
  --text-lg: 1.25rem;    /* 20px */
  --text-xl: 1.5rem;     /* 24px */
  --text-2xl: 2rem;      /* 32px */
  --text-3xl: 2.5rem;    /* 40px - main heading */

  /* Font Weights (limit to 3) */
  --font-normal: 400;
  --font-semibold: 600;
  --font-bold: 700;

  /* Line Heights */
  --line-height-tight: 1.2;
  --line-height-normal: 1.6;
  --line-height-relaxed: 1.8;

  /* ========================================
     LAYOUT
     ======================================== */
  --max-width: 1200px;
  --border-radius: 8px;

  /* ========================================
     TRANSITIONS
     ======================================== */
  --transition-fast: 0.15s ease;
  --transition-base: 0.2s ease;

  /* ========================================
     BREAKPOINTS (for reference in JS)
     ======================================== */
  --breakpoint-mobile: 768px;
  --breakpoint-desktop: 1024px;
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--text-md);
  font-weight: var(--font-normal);
  line-height: var(--line-height-normal);
  color: var(--black);
  background-color: var(--white);
  min-height: 100vh;
}

/* ========================================
   TYPOGRAPHY
   ======================================== */

/* Hierarchy with size and weight, not color */
h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-bold);
  line-height: var(--line-height-tight);
  margin-bottom: var(--space-md);
  color: var(--black);
}

h1 {
  font-size: var(--text-3xl);
}

h2 {
  font-size: var(--text-2xl);
}

h3 {
  font-size: var(--text-xl);
}

h4 {
  font-size: var(--text-lg);
}

h5, h6 {
  font-size: var(--text-md);
}

p {
  margin-bottom: var(--space-md);
}

/* Links */
a {
  color: var(--primary-blue);
  text-decoration: none;
  transition: opacity var(--transition-fast);
}

a:hover {
  opacity: 0.85; /* Opacity change, NOT gradient */
}

a:focus-visible {
  outline: 2px solid var(--primary-blue);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Lists */
ul, ol {
  margin-bottom: var(--space-md);
  padding-left: var(--space-lg);
}

/* Images */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ========================================
   LAYOUT UTILITIES
   ======================================== */

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

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

.section {
  padding: var(--space-2xl) 0;
}

/* Grid - responsive */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-xl);
}

@media (max-width: 768px) {
  .grid {
    grid-template-columns: 1fr;
  }
}

/* ========================================
   ACCESSIBILITY
   ======================================== */

/* Screen reader only content */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Skip navigation link */
.skip-link {
  position: absolute;
  top: -40px;
  left: 0;
  background: var(--primary-blue);
  color: var(--white);
  padding: var(--space-sm) var(--space-md);
  text-decoration: none;
  z-index: 100;
}

.skip-link:focus {
  top: 0;
}

/* Focus indicators - visible on all interactive elements */
:focus-visible {
  outline: 2px solid var(--primary-blue);
  outline-offset: 2px;
}

button:focus-visible,
a:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--primary-blue);
  outline-offset: 2px;
}

/* ========================================
   UTILITY CLASSES
   ======================================== */

/* Text alignment */
.text-center {
  text-align: center;
}

.text-right {
  text-align: right;
}

/* Spacing utilities */
.mt-0 { margin-top: 0; }
.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-0 { margin-bottom: 0; }
.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }

/* ========================================
   COMPONENT PLACEHOLDERS
   ======================================== */

/* Component loading states - prevent layout shift */
#navbar-placeholder,
#footer-placeholder {
  min-height: 64px;
}

/* ========================================
   DESIGN SYSTEM ENFORCEMENT
   ======================================== */

/* NO gradients - this is intentionally empty to document the rule */
/* NO floating shapes - avoid absolutely positioned decorative elements */
/* NO neon colors - stick to defined color palette */
/* NO heavy shadows - use subtle shadows only (see components.css) */
/* Limit to 2-3 colors per screen */
/* Use generous whitespace - don't fill every pixel */