/**
 * Yudame Research Design System - Foundation Styles
 * CSS Variables and base styles
 * DO NOT modify these values - they are locked from the design specification
 */

:root {
  /* === COLORS === */
  /* Foundation - Use 95% of the time */
  --color-black: #000000;
  --color-white: #FFFFFF;
  --color-cream: #F5F1E8;

  /* Salmon Accent - Use sparingly for emphasis */
  --color-salmon: #E8B4A8;
  --color-salmon-light: #F5D5CC;
  --color-salmon-medium: #D89B8E;
  --color-salmon-dark: #C8867A;

  /* Grays - Supporting roles only */
  --color-gray-100: #F5F5F5;
  --color-gray-200: #E5E5E5;
  --color-gray-300: #D4D4D4;
  --color-gray-600: #6B6B6B;
  --color-gray-800: #3A3A3A;
  --color-off-white: #FAFAF9;

  /* Supporting Accents - Data visualization only */
  --color-teal: #4A7C8C;
  --color-yellow: #E8C547;
  --color-rust: #C8867A;

  /* === TYPOGRAPHY === */
  /* Font families */
  --font-serif: 'Playfair Display', Georgia, serif;
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-mono: 'IBM Plex Mono', 'Courier New', monospace;

  /* Font sizes - Headlines */
  --text-5xl: 60px;
  --text-4xl: 48px;
  --text-3xl: 36px;
  --text-2xl: 32px;
  --text-xl: 24px;

  /* Font sizes - Body */
  --text-lg: 18px;
  --text-base: 16px;
  --text-sm: 14px;
  --text-xs: 12px;

  /* Line heights */
  --leading-none: 1.0;
  --leading-tight: 1.1;
  --leading-snug: 1.2;
  --leading-normal: 1.3;
  --leading-relaxed: 1.5;
  --leading-loose: 1.6;

  /* Font weights */
  --weight-normal: 400;
  --weight-medium: 500;
  --weight-semibold: 600;
  --weight-bold: 700;

  /* === SPACING === */
  /* 8px base scale - ONLY use these values */
  --space-1: 8px;
  --space-2: 16px;
  --space-3: 24px;
  --space-4: 32px;
  --space-5: 40px;
  --space-6: 48px;
  --space-8: 64px;
  --space-10: 80px;
  --space-12: 96px;

  /* === BORDERS === */
  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-full: 9999px;

  --border-width: 1px;
  --border-width-thick: 2px;

  /* === SHADOWS === */
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
  --shadow-scroll: 0 2px 8px rgba(0, 0, 0, 0.04);

  /* === TRANSITIONS === */
  /* LOCKED: All transitions use 200ms ease */
  --transition-base: 200ms ease;

  /* === BREAKPOINTS === */
  --breakpoint-mobile: 375px;
  --breakpoint-tablet: 768px;
  --breakpoint-desktop: 1024px;
  --breakpoint-wide: 1440px;

  /* === LAYOUT === */
  --max-width-content: 1200px;
  --max-width-article: 680px;
  --max-width-dashboard: 1400px;

  /* === COMPONENT SPECIFIC === */
  --header-height-desktop: 80px;
  --header-height-mobile: 64px;
  --nav-spacing: 32px;
  --card-padding-desktop: 32px;
  --card-padding-mobile: 24px;
}

/* === BASE STYLES === */

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

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

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-loose);
  color: var(--color-black);
  background-color: var(--color-white);
}

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

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-snug);
  margin-bottom: var(--space-3);
}

h1 {
  font-size: var(--text-5xl);
  line-height: var(--leading-tight);
  letter-spacing: -0.02em;
}

h2 {
  font-size: var(--text-4xl);
  line-height: var(--leading-snug);
  letter-spacing: -0.01em;
}

h3 {
  font-size: var(--text-3xl);
  line-height: var(--leading-normal);
}

h4 {
  font-size: var(--text-xl);
  line-height: var(--leading-normal);
}

p {
  margin-bottom: var(--space-3);
}

a {
  color: var(--color-black);
  text-decoration: underline;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-salmon);
}

a:focus {
  outline: 2px solid var(--color-salmon);
  outline-offset: 2px;
  border-radius: 2px;
}

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

@media (max-width: 768px) {
  h1 {
    font-size: var(--text-2xl);
    line-height: var(--leading-snug);
    letter-spacing: -0.01em;
  }

  h2 {
    font-size: var(--text-xl);
    line-height: var(--leading-snug);
  }

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

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

.container {
  width: 100%;
  max-width: var(--max-width-content);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6);
  padding-right: var(--space-6);
}

@media (max-width: 768px) {
  .container {
    padding-left: var(--space-3);
    padding-right: var(--space-3);
  }
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}