/* ==========================================================================
   CHALK v2 Design System
   Neo-brutalist tech aesthetic. Sharp edges. Zero radius. All signal.
   ========================================================================== */

/* --- Fonts --- */
/* SF Pro via system font stack — no import needed on Apple devices,
   falls back gracefully on other platforms */

@font-face {
  font-family: 'Tungsten Narrow';
  src: url('../assets/fonts/Tungsten-Font/WOFF2/TungstenNarrow-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

@font-face {
  font-family: 'Tungsten';
  src: url('../assets/fonts/Tungsten-Font/WOFF2/Tungsten-Bold.woff2') format('woff2');
  font-weight: 700;
  font-style: normal;
  font-display: swap;
}

/* ==========================================================================
   Design Tokens
   ========================================================================== */

:root,
[data-theme="dark"] {
  /* --- Color: Dark (default) --- */
  --color-bg: #0C0C0C;
  --color-surface: #161616;
  --color-surface-2: #1E1E1E;
  --color-text: #EDEDEC;
  --color-text-secondary: #8A8A8A;
  --color-text-muted: #555555;
  --color-accent: #D4625A;
  --color-accent-hover: #E07068;
  --color-border: #2A2A2A;
  --color-border-hover: #404040;
  --color-code-bg: #1A1A1A;

  /* --- Neo-Brutalist --- */
  --radius: 0px;
  --shadow-brutal: 4px 4px 0 var(--color-text);
  --shadow-brutal-sm: 2px 2px 0 var(--color-text);
  --shadow-brutal-accent: 4px 4px 0 var(--color-accent);
  --border-width: 2px;
  --border: var(--border-width) solid var(--color-border);
  --border-strong: var(--border-width) solid var(--color-text);

  /* --- Spacing --- */
  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 64px;
  --space-9: 96px;

  /* --- Transitions --- */
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --duration: 200ms;
  --duration-slow: 500ms;

  /* --- Font Stacks --- */
  --font-display-narrow: 'Tungsten Narrow', 'Impact', 'Arial Narrow', sans-serif;
  --font-display: 'Tungsten', 'Impact', sans-serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'SF Pro Display', 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --font-mono: 'SF Mono', 'Fira Code', 'Fira Mono', 'Roboto Mono', 'Courier New', monospace;
}

[data-theme="light"] {
  --color-bg: #FAFAF9;
  --color-surface: #FFFFFF;
  --color-surface-2: #F5F5F4;
  --color-text: #1C1C1A;
  --color-text-secondary: #6B6B6B;
  --color-text-muted: #999999;
  --color-accent: #CA4D44;
  --color-accent-hover: #B8423A;
  --color-border: #E5E5E3;
  --color-border-hover: #D0D0CE;
  --color-code-bg: #F0F0EE;
}

/* ==========================================================================
   Reset
   ========================================================================== */

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

html {
  -webkit-text-size-adjust: 100%;
  -moz-text-size-adjust: 100%;
  text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

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

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

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

ul,
ol {
  list-style: none;
}

a {
  color: inherit;
  text-decoration: none;
}

/* ==========================================================================
   Base Typography
   ========================================================================== */

body {
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color var(--duration-slow) var(--ease),
              color var(--duration) var(--ease);
}

h1 {
  font-family: var(--font-display-narrow);
  font-size: clamp(3.5rem, 10vw, 8rem);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: -0.03em;
  line-height: 0.9;
  color: var(--color-text);
}

h2 {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 4rem);
  font-weight: 700;
  text-transform: uppercase;
  line-height: 0.95;
  color: var(--color-text);
}

h3 {
  font-family: var(--font-display);
  font-size: clamp(1.25rem, 3vw, 2rem);
  font-weight: 700;
  text-transform: uppercase;
  color: var(--color-text);
}

p {
  max-width: 60ch;
  color: var(--color-text-secondary);
  line-height: 1.7;
}

code,
pre {
  font-family: var(--font-mono);
}

::selection {
  background-color: var(--color-accent);
  color: #FFFFFF;
}

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

.container {
  width: 100%;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding-left: 24px;
  padding-right: 24px;
}

.container--narrow {
  max-width: 800px;
}

.container--wide {
  max-width: 1400px;
}

/* ==========================================================================
   Utility Classes
   ========================================================================== */

/* --- Grid --- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-5);
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-5);
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-5);
}

/* --- Flexbox --- */
.flex            { display: flex; }
.flex-col        { flex-direction: column; }
.items-center    { align-items: center; }
.items-start     { align-items: flex-start; }
.justify-between { justify-content: space-between; }
.justify-center  { justify-content: center; }
.flex-wrap       { flex-wrap: wrap; }

.gap-1  { gap: var(--space-1); }
.gap-2  { gap: var(--space-2); }
.gap-3  { gap: var(--space-3); }
.gap-4  { gap: var(--space-4); }
.gap-5  { gap: var(--space-5); }
.gap-6  { gap: var(--space-6); }
.gap-7  { gap: var(--space-7); }

/* --- Text --- */
.text-center    { text-align: center; }
.text-accent    { color: var(--color-accent); }
.text-secondary { color: var(--color-text-secondary); }
.text-muted     { color: var(--color-text-muted); }

/* --- Accessibility --- */
.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;
}

/* ==========================================================================
   Components: Buttons
   ========================================================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  padding: 12px 24px;
  font-family: var(--font-body);
  font-weight: 600;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  line-height: 1;
  border: 2px solid transparent;
  border-radius: var(--radius);
  cursor: pointer;
  transition: all var(--duration) var(--ease);
  white-space: nowrap;
}

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

.btn--primary:hover {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
  box-shadow: var(--shadow-brutal-accent);
  transform: translate(-2px, -2px);
}

.btn--outline {
  background-color: transparent;
  border: var(--border-strong);
  color: var(--color-text);
}

.btn--outline:hover {
  background-color: var(--color-text);
  color: var(--color-bg);
}

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

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

.btn--lg {
  padding: 16px 32px;
  font-size: 15px;
}

/* ==========================================================================
   Components: Cards
   ========================================================================== */

.card {
  background-color: var(--color-surface);
  border: var(--border);
  border-radius: var(--radius);
  padding: var(--space-6);
  transition: border-color var(--duration) var(--ease),
              transform var(--duration) var(--ease),
              box-shadow var(--duration) var(--ease);
}

.card:hover {
  border-color: var(--color-border-hover);
  transform: translate(-2px, -2px);
  box-shadow: var(--shadow-brutal-sm);
}

/* ==========================================================================
   Components: Badge / Tag
   ========================================================================== */

.badge {
  display: inline-flex;
  align-items: center;
  padding: 4px 12px;
  font-size: 12px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  line-height: 1;
  border: var(--border);
  border-radius: var(--radius);
  color: var(--color-text-secondary);
}

.badge--accent {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* ==========================================================================
   Components: Input
   ========================================================================== */

.input {
  width: 100%;
  padding: 14px 16px;
  background-color: var(--color-surface);
  border: var(--border);
  border-radius: var(--radius);
  color: var(--color-text);
  font-size: 15px;
  transition: border-color var(--duration) var(--ease),
              box-shadow var(--duration) var(--ease);
}

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

.input:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 1px var(--color-accent);
}

/* ==========================================================================
   Components: Divider
   ========================================================================== */

.divider {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-7) 0;
}

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

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: var(--space-4) 0;
  transition: background-color var(--duration) var(--ease),
              border-color var(--duration) var(--ease),
              backdrop-filter var(--duration) var(--ease);
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background-color: rgba(12, 12, 12, 0.95);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom-color: var(--color-border);
}

[data-theme="light"] .nav.scrolled {
  background-color: rgba(250, 250, 249, 0.95);
}

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

.nav__logo-link {
  display: flex;
  align-items: center;
}

.nav__logo {
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-text);
  line-height: 1;
}

.nav__links {
  display: flex;
  gap: var(--space-6);
  align-items: center;
  list-style: none;
}

.nav__link {
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color var(--duration) var(--ease);
}

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

/* --- Nav Actions (theme toggle + CTA) --- */
.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* --- Theme Toggle --- */
.theme-toggle {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: var(--border);
  border-radius: var(--radius);
  color: var(--color-text-secondary);
  background: transparent;
  cursor: pointer;
  transition: color var(--duration) var(--ease),
              border-color var(--duration) var(--ease);
}

.theme-toggle:hover {
  color: var(--color-text);
  border-color: var(--color-text);
}

/* Icon visibility: show sun in dark mode, moon in light mode */
.theme-toggle .icon-sun  { display: block; }
.theme-toggle .icon-moon { display: none; }

[data-theme="light"] .theme-toggle .icon-sun  { display: none; }
[data-theme="light"] .theme-toggle .icon-moon { display: block; }

/* --- Hamburger --- */
.nav__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 36px;
  height: 36px;
  gap: 5px;
  cursor: pointer;
  border: var(--border);
  background: transparent;
}

.nav__hamburger span {
  display: block;
  width: 18px;
  height: 2px;
  background-color: var(--color-text);
  transition: transform var(--duration) var(--ease),
              opacity var(--duration) var(--ease);
}

/* Hamburger open state */
.nav__hamburger.open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav__hamburger.open span:nth-child(2) {
  opacity: 0;
}

.nav__hamburger.open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* --- Mobile Nav Overlay --- */
.mobile-nav {
  position: fixed;
  inset: 0;
  z-index: 99;
  background-color: var(--color-bg);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-6);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--duration) var(--ease);
}

.mobile-nav.open {
  opacity: 1;
  pointer-events: all;
}

.mobile-nav__link {
  font-family: var(--font-display);
  font-size: clamp(2rem, 6vw, 3.5rem);
  text-transform: uppercase;
  color: var(--color-text);
  transition: color var(--duration) var(--ease);
}

.mobile-nav__link:hover {
  color: var(--color-accent);
}

.mobile-nav__link--accent {
  color: var(--color-accent);
}

/* --- Active Nav Link --- */
.nav__link--active {
  color: var(--color-text);
}

/* --- Nav CTA Button --- */
.btn--nav {
  padding: 10px 20px;
  font-size: 13px;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
  border-top: 1px solid var(--color-border);
  padding: var(--space-8) 0 var(--space-6);
  margin-top: var(--space-9);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--space-7);
}

.footer__heading {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-weight: 600;
  color: var(--color-text-muted);
  margin-bottom: var(--space-4);
}

.footer__links {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.footer__link {
  font-size: 14px;
  color: var(--color-text-secondary);
  transition: color var(--duration) var(--ease);
}

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

.footer__link--disabled {
  opacity: 0.4;
  cursor: default;
}

.footer__logo-text {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--color-text);
  line-height: 1;
  display: block;
  margin-bottom: var(--space-3);
}

.footer__tagline {
  font-size: 14px;
  color: var(--color-text-secondary);
  max-width: none;
}

.footer__bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-6);
  border-top: 1px solid var(--color-border);
  margin-top: var(--space-6);
  font-size: 13px;
  color: var(--color-text-muted);
}

/* ==========================================================================
   Animations
   ========================================================================== */

.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 600ms ease, transform 600ms ease;
}

.reveal.revealed {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children */
.stagger > * {
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 400ms ease, transform 400ms ease;
}

.stagger.revealed > *:nth-child(1) { transition-delay: 0ms; opacity: 1; transform: translateY(0); }
.stagger.revealed > *:nth-child(2) { transition-delay: 80ms; opacity: 1; transform: translateY(0); }
.stagger.revealed > *:nth-child(3) { transition-delay: 160ms; opacity: 1; transform: translateY(0); }
.stagger.revealed > *:nth-child(4) { transition-delay: 240ms; opacity: 1; transform: translateY(0); }
.stagger.revealed > *:nth-child(5) { transition-delay: 320ms; opacity: 1; transform: translateY(0); }

@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideIn {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

/* ==========================================================================
   Responsive: Tablet (max-width: 768px)
   ========================================================================== */

@media (max-width: 768px) {
  h1 {
    font-size: clamp(2.5rem, 8vw, 5rem);
  }

  h2 {
    font-size: clamp(1.75rem, 5vw, 3rem);
  }

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

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

  .grid-4 {
    grid-template-columns: repeat(2, 1fr);
  }

  .nav__links {
    display: none;
  }

  .nav__actions {
    display: none;
  }

  .nav__hamburger {
    display: flex;
  }

  .footer__grid {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-6);
  }

  .footer__brand {
    grid-column: 1 / -1;
  }

  .footer__bottom {
    flex-direction: column;
    gap: var(--space-3);
    text-align: center;
  }
}

/* ==========================================================================
   Responsive: Mobile (max-width: 480px)
   ========================================================================== */

@media (max-width: 480px) {
  h1 {
    font-size: clamp(2rem, 10vw, 3.5rem);
  }

  h2 {
    font-size: clamp(1.5rem, 6vw, 2.5rem);
  }

  .container {
    padding-left: 16px;
    padding-right: 16px;
  }

  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .footer__grid {
    grid-template-columns: 1fr;
  }

  .card {
    padding: var(--space-5);
  }

  .btn--lg {
    padding: 14px 24px;
    font-size: 14px;
    width: 100%;
  }
}