/* =========================================
   APPLE-INSPIRED DESIGN SYSTEM
   Single source of truth for typography, spacing, colors, and interactions
========================================= */

:root {
  /* ===== TYPOGRAPHY HIERARCHY ===== */
  --font-family-primary: Inter, system-ui, -apple-system, Segoe UI, Roboto, Helvetica Neue, Arial, sans-serif;
  
  /* Font sizes (modular scale) */
  --font-size-h1: clamp(32px, 4vw, 56px);    /* Hero headings */
  --font-size-h2: clamp(24px, 3vw, 32px);    /* Section titles */
  --font-size-h3: 20px;                       /* Subsection titles */
  --font-size-body: 17px;                     /* Body text, primary */
  --font-size-body-sm: 16px;                  /* Body text, secondary */
  --font-size-meta: 14px;                     /* Metadata, captions */
  --font-size-micro: 12px;                    /* Tags, timestamps */
  
  /* Line heights */
  --line-height-tight: 1.2;    /* Headings */
  --line-height-normal: 1.5;   /* Subheadings */
  --line-height-relaxed: 1.65; /* Body text */
  --line-height-loose: 1.8;    /* Long-form content */
  
  /* Letter spacing */
  --letter-spacing-tight: -0.03em;  /* Headings */
  --letter-spacing-normal: -0.01em; /* Subheadings */
  --letter-spacing-relaxed: 0;      /* Body */
  
  /* Font weights */
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;
  
  /* ===== SPACING SCALE (8px base) ===== */
  --space-xs: 8px;      /* 1 unit */
  --space-sm: 16px;     /* 2 units */
  --space-md: 24px;     /* 3 units */
  --space-lg: 40px;     /* 5 units */
  --space-xl: 56px;     /* 7 units */
  --space-2xl: 64px;    /* 8 units */
  --space-3xl: 80px;    /* 10 units */
  --space-4xl: 96px;    /* 12 units */
  --space-5xl: 120px;   /* 15 units */
  
  /* ===== COLOR PALETTE ===== */
  /* Primary brand colors */
  --color-brand-blue: #0ea5e9;    /* CTAs, primary accent */
  --color-brand-indigo: #6366f1;  /* Secondary accent, hover states */
  
  /* Neutral colors */
  --color-text-primary: #0f172a;    /* Headings, strong text */
  --color-text-secondary: #475569;  /* Body text */
  --color-text-tertiary: #64748b;   /* Secondary text, metadata */
  --color-text-disabled: #94a3b8;   /* Disabled states */
  
  --color-bg-primary: #ffffff;      /* Default background */
  --color-bg-secondary: #f8fafc;    /* Subtle background */
  --color-bg-tertiary: #f1f5f9;     /* Slightly darker background */
  
  /* Borders and dividers */
  --color-border-light: #e5e7eb;    /* Light dividers */
  --color-border-normal: #cbd5e1;   /* Standard borders */
  
  /* Semantic colors */
  --color-gradient-brand: linear-gradient(135deg, var(--color-brand-blue), var(--color-brand-indigo));
  
  /* ===== INTERACTION ===== */
  --transition-fast: 0.2s;
  --transition-normal: 0.3s;
  --transition-slow: 0.6s;
  --easing: cubic-bezier(0.4, 0, 0.2, 1);
  
  /* ===== LAYOUT ===== */
  --max-width-narrow: 900px;   /* Main content width */
  --max-width-wide: 1200px;    /* Expanded layout width */
  --gutter: var(--space-md);   /* Horizontal padding on containers */
  
  /* Border radius */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.07);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 12px 32px rgba(0, 0, 0, 0.12);
}

/* ===== SEMANTIC TYPOGRAPHY CLASSES ===== */

.heading-1 {
  font-size: var(--font-size-h1);
  font-weight: var(--font-weight-extrabold);
  line-height: var(--line-height-tight);
  letter-spacing: var(--letter-spacing-tight);
  color: var(--color-text-primary);
  margin-bottom: var(--space-md);
}

.heading-2 {
  font-size: var(--font-size-h2);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-normal);
  letter-spacing: var(--letter-spacing-normal);
  color: var(--color-text-primary);
  margin-bottom: var(--space-md);
}

.heading-3 {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-normal);
  color: var(--color-text-primary);
  margin-bottom: var(--space-sm);
}

.body-text {
  font-size: var(--font-size-body);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-md);
}

.body-text-sm {
  font-size: var(--font-size-body-sm);
  line-height: var(--line-height-relaxed);
  color: var(--color-text-secondary);
}

.text-meta {
  font-size: var(--font-size-meta);
  line-height: var(--line-height-normal);
  color: var(--color-text-tertiary);
}

.text-micro {
  font-size: var(--font-size-micro);
  letter-spacing: 0.02em;
  color: var(--color-text-disabled);
  text-transform: uppercase;
}

/* ===== SPACING UTILITIES ===== */

.p-xs { padding: var(--space-xs); }
.p-sm { padding: var(--space-sm); }
.p-md { padding: var(--space-md); }
.p-lg { padding: var(--space-lg); }
.p-xl { padding: var(--space-xl); }

.px-sm { padding-left: var(--space-sm); padding-right: var(--space-sm); }
.px-md { padding-left: var(--space-md); padding-right: var(--space-md); }

.py-sm { padding-top: var(--space-sm); padding-bottom: var(--space-sm); }
.py-md { padding-top: var(--space-md); padding-bottom: var(--space-md); }
.py-lg { padding-top: var(--space-lg); padding-bottom: var(--space-lg); }
.py-xl { padding-top: var(--space-xl); padding-bottom: var(--space-xl); }

.gap-sm { gap: var(--space-sm); }
.gap-md { gap: var(--space-md); }
.gap-lg { gap: var(--space-lg); }

/* Margin utilities */
.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-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); }

/* ===== LAYOUT CONTAINERS ===== */

.container {
  width: 100%;
  max-width: var(--max-width-narrow);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

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

.container--full {
  max-width: 100%;
  padding-left: 0;
  padding-right: 0;
}

.section {
  padding-top: var(--space-3xl);
  padding-bottom: var(--space-3xl);
  border-top: 1px solid var(--color-border-light);
}

.section:first-child {
  border-top: none;
}

/* ===== INTERACTION STATES ===== */

.link-primary {
  color: var(--color-brand-blue);
  font-weight: var(--font-weight-semibold);
  text-decoration: none;
  transition: color var(--transition-normal) var(--easing);
  position: relative;
}

.link-primary:hover {
  color: var(--color-brand-indigo);
}

.link-cta {
  display: inline-block;
  color: var(--color-text-primary);
  font-weight: var(--font-weight-semibold);
  padding: var(--space-sm) var(--space-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-normal) var(--easing);
  background-color: transparent;
  border: 1px solid var(--color-border-normal);
}

.link-cta:hover {
  background-color: var(--color-bg-secondary);
  border-color: var(--color-text-primary);
}

.btn-primary {
  display: inline-block;
  padding: var(--space-sm) var(--space-lg);
  background: var(--color-brand-blue);
  color: white;
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-body-sm);
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition-normal) var(--easing);
}

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

/* ===== FADE-IN ANIMATION (SUBTLE) ===== */

@keyframes fadeIn {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in {
  animation: fadeIn var(--transition-slow) var(--easing);
}

.animate-fade-in-up {
  animation: fadeInUp var(--transition-slow) var(--easing);
}

/* ===== UNIFIED CARD SYSTEM ===== */

/* Base card styles */
.card {
  background: var(--color-bg-primary);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition-normal) var(--easing);
}

.card:hover {
  border-color: var(--color-border-normal);
  box-shadow: var(--shadow-md);
}

/* Featured card variant - for showcase items with images */
.card--featured {
  background: var(--color-bg-primary);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-xl);
  overflow: hidden;
  transition: all var(--transition-normal) var(--easing);
  box-shadow: var(--shadow-sm);
}

.card--featured:hover {
  transform: translateY(-4px);
  border-color: var(--color-border-normal);
  box-shadow: var(--shadow-lg);
}

/* Card header - for images or media */
.card__header {
  width: 100%;
  background: var(--color-bg-secondary);
  position: relative;
  overflow: hidden;
}

.card__header img,
.card__header video {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
}

/* Featured card header sizing */
.card--featured .card__header {
  height: 280px;
}

.card--featured .card__header::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 0%, rgba(0,0,0,0.04) 100%);
}

/* Card body - for content */
.card__body {
  padding: var(--space-lg);
}

.card--featured .card__body {
  padding: var(--space-2xl);
}

/* Card title */
.card__title {
  font-size: var(--font-size-h3);
  font-weight: var(--font-weight-bold);
  color: var(--color-text-primary);
  margin-bottom: var(--space-sm);
}

.card--featured .card__title {
  font-size: clamp(20px, 2.5vw, 28px);
  margin-bottom: var(--space-md);
}

/* Card description */
.card__description {
  font-size: var(--font-size-body-sm);
  color: var(--color-text-secondary);
  line-height: var(--line-height-relaxed);
  margin-bottom: var(--space-md);
}

.card--featured .card__description {
  font-size: var(--font-size-body);
  margin-bottom: var(--space-lg);
}

/* Card tag/category */
.card__tag {
  display: inline-block;
  font-size: var(--font-size-micro);
  font-weight: var(--font-weight-bold);
  color: var(--color-brand-blue);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: var(--space-sm);
}

/* Card link/CTA */
.card__link {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  color: var(--color-brand-blue);
  font-weight: var(--font-weight-semibold);
  text-decoration: none;
  transition: all var(--transition-normal) var(--easing);
}

.card__link:hover {
  gap: var(--space-sm);
  color: var(--color-brand-indigo);
}

/* ===== CUSTOM SVG ICONS ===== */

.icon-svg {
  display: inline-block;
  width: 48px;
  height: 48px;
  color: var(--color-brand-blue);
  stroke-width: 1.5;
}

.icon-svg.icon-small {
  width: 32px;
  height: 32px;
}

.icon-svg.icon-large {
  width: 64px;
  height: 64px;
}

/* ===== IMAGE PLACEHOLDER SYSTEM ===== */

.image--placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--color-bg-secondary) 0%, var(--color-bg-tertiary) 100%);
  color: var(--color-text-tertiary);
  font-size: 64px;
  aspect-ratio: 16 / 9;
  border-radius: var(--radius-lg);
  position: relative;
  overflow: hidden;
}

.image--placeholder::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, transparent 0%, rgba(0, 0, 0, 0.03) 100%);
  pointer-events: none;
}

.image--placeholder.image--small {
  aspect-ratio: 3 / 2;
  font-size: 48px;
}

.image--placeholder.image--wide {
  aspect-ratio: 21 / 9;
  font-size: 80px;
}

.image--placeholder.image--square {
  aspect-ratio: 1 / 1;
  font-size: 56px;
}

/* Image without source or fallback */
.image--blank {
  background: var(--color-bg-secondary);
  border: 1px dashed var(--color-border-light);
  border-radius: var(--radius-lg);
}

/* ===== STANDARDIZED CTA PATTERNS ===== */

/* Primary CTA - main action */
.cta--primary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-lg);
  background: var(--color-brand-blue);
  color: white;
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-body-sm);
  border-radius: var(--radius-md);
  text-decoration: none;
  transition: all var(--transition-normal) var(--easing);
  border: none;
  cursor: pointer;
}

.cta--primary:hover {
  background: var(--color-brand-indigo);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

/* Secondary CTA - explore/learn more */
.cta--secondary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  color: var(--color-brand-blue);
  font-weight: var(--font-weight-semibold);
  text-decoration: none;
  transition: all var(--transition-normal) var(--easing);
}

.cta--secondary:hover {
  gap: var(--space-sm);
  color: var(--color-brand-indigo);
}

/* Tertiary CTA - subtle action */
.cta--tertiary {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-xs) var(--space-sm);
  color: var(--color-text-secondary);
  font-size: var(--font-size-body-sm);
  text-decoration: none;
  transition: all var(--transition-normal) var(--easing);
  border: 1px solid var(--color-border-light);
  border-radius: var(--radius-md);
}

.cta--tertiary:hover {
  color: var(--color-text-primary);
  border-color: var(--color-text-primary);
  background: var(--color-bg-secondary);
}

/* Arrow indicator for CTAs */
.cta__arrow {
  display: inline-block;
  transition: transform var(--transition-normal) var(--easing);
}

.cta--secondary:hover .cta__arrow,
.cta--primary:hover .cta__arrow {
  transform: translateX(4px);
}

/* CTA text label - use with ::before for consistency */
.cta--explore::after {
  content: ' →';
}

.cta--view::after {
  content: ' →';
}

.cta--read::after {
  content: ' →';
}

.cta--open::after {
  content: ' →';
}