/* ============================================================
   Design Tokens
   Inspired by ElevenLabs.io — light-first, clean AI SaaS
   ============================================================ */

:root {

  /* ----------------------------------------------------------
     Colors — Base
  ---------------------------------------------------------- */
  --color-bg:           #FFFFFF;
  --color-bg-elevated:  #F9F9F9;
  --color-bg-subtle:    #F3F3F3;
  --color-border:       #E8E8E8;
  --color-border-strong:#C8C8C8;

  /* ----------------------------------------------------------
     Colors — Text
  ---------------------------------------------------------- */
  --color-text-primary:   #0A0A0A;
  --color-text-secondary: #6B6B6B;
  --color-text-muted:     #A3A3A3;

  /* ----------------------------------------------------------
     Colors — Accent (Black CTA)
  ---------------------------------------------------------- */
  --color-accent:        #0A0A0A;
  --color-accent-hover:  #2A2A2A;
  --color-accent-subtle: #F3F3F3;

  /* ----------------------------------------------------------
     Colors — Gradient (Hero, Feature Sections)
  ---------------------------------------------------------- */
  --color-gradient-start: #1D4ED8;
  --color-gradient-end:   #7C3AED;
  --color-gradient: linear-gradient(135deg, #1D4ED8, #7C3AED);

  /* ----------------------------------------------------------
     Colors — Semantic
  ---------------------------------------------------------- */
  --color-success: #16A34A;
  --color-warning: #D97706;
  --color-error:   #DC2626;

  /* ----------------------------------------------------------
     Typography — Family
  ---------------------------------------------------------- */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* ----------------------------------------------------------
     Typography — Size
  ---------------------------------------------------------- */
  --text-display: 72px;
  --text-h1:      56px;
  --text-h2:      40px;
  --text-h3:      28px;
  --text-h4:      20px;
  --text-body-lg: 18px;
  --text-body:    16px;
  --text-body-sm: 14px;
  --text-label:   12px;

  /* ----------------------------------------------------------
     Typography — Line Height
  ---------------------------------------------------------- */
  --leading-display: 1.05;
  --leading-heading: 1.15;
  --leading-body:    1.6;
  --leading-label:   1.4;

  /* ----------------------------------------------------------
     Typography — Weight
  ---------------------------------------------------------- */
  --weight-regular: 400;
  --weight-medium:  500;
  --weight-semibold:600;
  --weight-bold:    700;

  /* ----------------------------------------------------------
     Typography — Letter Spacing
  ---------------------------------------------------------- */
  --tracking-display: -0.03em;
  --tracking-heading: -0.02em;
  --tracking-body:     0;
  --tracking-label:    0.05em;

  /* ----------------------------------------------------------
     Spacing (base unit: 8px)
  ---------------------------------------------------------- */
  --space-1:  4px;
  --space-2:  8px;
  --space-3:  12px;
  --space-4:  16px;
  --space-5:  24px;
  --space-6:  32px;
  --space-8:  48px;
  --space-10: 64px;
  --space-12: 80px;
  --space-16: 120px;

  /* ----------------------------------------------------------
     Border Radius
  ---------------------------------------------------------- */
  --radius-sm:   6px;
  --radius-md:   10px;
  --radius-lg:   16px;
  --radius-xl:   24px;
  --radius-full: 9999px;

  /* ----------------------------------------------------------
     Shadows & Elevation
  ---------------------------------------------------------- */
  --shadow-sm:       0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md:       0 4px 16px rgba(0,0,0,0.08), 0 2px 4px rgba(0,0,0,0.04);
  --shadow-lg:       0 8px 40px rgba(0,0,0,0.12), 0 4px 8px rgba(0,0,0,0.04);
  --shadow-glow:     0 0 0 3px rgba(0,0,0,0.08);
  --shadow-glow-blue:0 0 32px rgba(99,102,241,0.2);

  /* ----------------------------------------------------------
     Layout
  ---------------------------------------------------------- */
  --container-max-width: 1200px;
  --container-padding:   24px;

  /* ----------------------------------------------------------
     Transitions
  ---------------------------------------------------------- */
  --transition-fast:   150ms ease;
  --transition-base:   200ms ease-out;
  --transition-slow:   300ms cubic-bezier(0.4, 0, 0.2, 1);

  /* ----------------------------------------------------------
     Z-Index Scale
  ---------------------------------------------------------- */
  --z-base:    0;
  --z-raised:  10;
  --z-dropdown:100;
  --z-sticky:  200;
  --z-overlay: 300;
  --z-modal:   400;
  --z-toast:   500;
}

/* ============================================================
   Global Reset & Base Styles
   ============================================================ */

*, *::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-body);
  font-weight: var(--weight-regular);
  line-height: var(--leading-body);
  color: var(--color-text-primary);
  background-color: var(--color-bg);
}

/* ============================================================
   Typography Utilities
   ============================================================ */

.text-display {
  font-size: var(--text-display);
  font-weight: var(--weight-bold);
  line-height: var(--leading-display);
  letter-spacing: var(--tracking-display);
}

.text-h1 {
  font-size: var(--text-h1);
  font-weight: var(--weight-bold);
  line-height: var(--leading-display);
  letter-spacing: var(--tracking-display);
}

.text-h2 {
  font-size: var(--text-h2);
  font-weight: var(--weight-bold);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

.text-h3 {
  font-size: var(--text-h3);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-heading);
  letter-spacing: var(--tracking-heading);
}

.text-h4 {
  font-size: var(--text-h4);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-body);
}

.text-body-lg  { font-size: var(--text-body-lg); line-height: var(--leading-body); }
.text-body     { font-size: var(--text-body);    line-height: var(--leading-body); }
.text-body-sm  { font-size: var(--text-body-sm); line-height: var(--leading-body); }
.text-label    { font-size: var(--text-label); line-height: var(--leading-label); letter-spacing: var(--tracking-label); font-weight: var(--weight-medium); }

.text-secondary { color: var(--color-text-secondary); }
.text-muted     { color: var(--color-text-muted); }
.text-gradient  {
  background: var(--color-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================================
   Layout Utilities
   ============================================================ */

.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section {
  padding: var(--space-16) 0;
}

.section--elevated {
  background-color: var(--color-bg-elevated);
}

/* ============================================================
   Buttons
   ============================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px 24px;
  font-family: var(--font-family);
  font-size: 15px;
  font-weight: var(--weight-semibold);
  line-height: 1;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  text-decoration: none;
  transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast), opacity var(--transition-fast);
  white-space: nowrap;
}

.btn:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

.btn--primary {
  background: var(--color-accent);
  color: #FFFFFF;
}

.btn--primary:hover {
  background: var(--color-accent-hover);
}

.btn--secondary {
  background: transparent;
  color: var(--color-text-primary);
  border: 1px solid var(--color-border-strong);
}

.btn--secondary:hover {
  background: var(--color-bg-subtle);
  border-color: #A0A0A0;
}

.btn--ghost {
  background: transparent;
  color: var(--color-text-secondary);
  padding: 8px 0;
}

.btn--ghost:hover {
  color: var(--color-text-primary);
  text-decoration: underline;
}

.btn--sm {
  padding: 8px 16px;
  font-size: 13px;
}

.btn--lg {
  padding: 16px 32px;
  font-size: 17px;
}

/* ============================================================
   Cards
   ============================================================ */

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-5);
  box-shadow: var(--shadow-sm);
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

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

.card--featured {
  border-color: #0A0A0A;
  box-shadow: var(--shadow-md);
}

/* ============================================================
   Badges
   ============================================================ */

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 4px 10px;
  border-radius: var(--radius-full);
  font-size: var(--text-label);
  font-weight: var(--weight-medium);
  letter-spacing: var(--tracking-label);
}

.badge--default {
  background: var(--color-bg-subtle);
  color: var(--color-text-secondary);
  border: 1px solid var(--color-border);
}

.badge--dark {
  background: var(--color-accent);
  color: #FFFFFF;
}

.badge--gradient {
  background: var(--color-gradient);
  color: #FFFFFF;
}

.badge--success {
  background: #DCFCE7;
  color: var(--color-success);
  border: 1px solid #BBF7D0;
}

/* ============================================================
   Navigation
   ============================================================ */

.nav {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  height: 64px;
  display: flex;
  align-items: center;
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  list-style: none;
}

.nav__link {
  font-size: var(--text-body-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.nav__link:hover {
  color: var(--color-text-primary);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

/* ============================================================
   Hero Section
   ============================================================ */

.hero {
  padding: var(--space-16) 0 var(--space-12);
  text-align: center;
  position: relative;
  overflow: hidden;
  background: var(--color-bg);
}

.hero__eyebrow {
  margin-bottom: var(--space-5);
}

.hero__headline {
  font-size: var(--text-display);
  font-weight: var(--weight-bold);
  line-height: var(--leading-display);
  letter-spacing: var(--tracking-display);
  max-width: 900px;
  margin: 0 auto var(--space-5);
  color: var(--color-text-primary);
}

.hero__description {
  font-size: var(--text-body-lg);
  color: var(--color-text-secondary);
  max-width: 600px;
  margin: 0 auto var(--space-8);
}

.hero__cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

/* ============================================================
   Logo Grid (Social Proof)
   ============================================================ */

.logo-grid {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: var(--space-6) var(--space-8);
  opacity: 0.4;
  filter: grayscale(100%);
  transition: opacity var(--transition-base), filter var(--transition-base);
}

.logo-grid:hover {
  opacity: 0.8;
  filter: grayscale(0%);
}

/* ============================================================
   Blog / Content Cards Grid
   ============================================================ */

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-5);
}

.content-card__thumbnail {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: var(--radius-md);
  margin-bottom: var(--space-4);
}

/* ============================================================
   Form Inputs
   ============================================================ */

.input {
  display: block;
  width: 100%;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 12px 16px;
  font-family: var(--font-family);
  font-size: var(--text-body);
  color: var(--color-text-primary);
  outline: none;
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.input::placeholder {
  color: var(--color-text-muted);
}

.input:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(0,0,0,0.06);
}

/* ============================================================
   Divider
   ============================================================ */

.divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-8) 0;
}

/* ============================================================
   Accessibility — Focus & Motion
   ============================================================ */

:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ============================================================
   Responsive Breakpoints
   ============================================================ */

@media (max-width: 1024px) {
  :root {
    --text-display: 56px;
    --text-h1:      44px;
    --text-h2:      32px;
  }
}

@media (max-width: 640px) {
  :root {
    --text-display: 40px;
    --text-h1:      32px;
    --text-h2:      26px;
    --text-h3:      22px;
    --container-padding: 16px;
    --space-16: 80px;
    --space-12: 60px;
  }
}