/* ============================================
   BASE STYLESHEET
   ============================================ */

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  scroll-padding-top: var(--space-16);
  hanging-punctuation: first last;
}

body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
}

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

ul[role='list'], ol[role='list'] { list-style: none; }

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

h1, h2, h3, h4, h5, h6 {
  text-wrap: balance;
  line-height: 1.1;
  font-family: var(--font-display);
  letter-spacing: -0.02em;
}

p, li, figcaption {
  text-wrap: pretty;
  max-width: 72ch;
}

::selection {
  background: var(--color-primary);
  color: var(--color-text-inverse);
}

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

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

a, button, [role='button'], [role='link'], input, textarea, select {
  transition:
    color var(--transition-interactive),
    background var(--transition-interactive),
    border-color var(--transition-interactive),
    box-shadow var(--transition-interactive),
    opacity var(--transition-interactive);
}

.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;
}

/* ============================================
   SHARED LAYOUT
   ============================================ */

.container {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-4), 5vw, var(--space-16));
}

.container--narrow {
  max-width: var(--content-default);
}

/* ============================================
   SHARED COMPONENTS
   ============================================ */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  border-radius: var(--radius-full);
  font-family: var(--font-body);
  font-size: var(--text-sm);
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  text-decoration: none;
  cursor: pointer;
  border: 2px solid transparent;
}

.btn--primary {
  background: var(--color-primary);
  color: var(--color-text-inverse);
  border-color: var(--color-primary);
}
.btn--primary:hover {
  background: var(--color-primary-hover);
  border-color: var(--color-primary-hover);
  transform: translateY(-1px);
  box-shadow: var(--shadow-glow);
}

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

.btn--lg {
  padding: var(--space-4) var(--space-8);
  font-size: var(--text-base);
}

/* Section label */
.section-label {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-primary);
  margin-bottom: var(--space-4);
}
.section-label::before {
  content: '';
  display: block;
  width: 24px;
  height: 2px;
  background: var(--color-primary);
}

/* Divider line */
.divider {
  height: 1px;
  background: var(--color-divider);
  border: none;
  margin-block: var(--space-12);
}

/* ============================================
   HEADER / NAV
   ============================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in oklab, var(--color-bg) 90%, transparent);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--color-divider);
  transition: box-shadow var(--transition-slow);
}

.site-header.scrolled {
  box-shadow: var(--shadow-md);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  text-decoration: none;
}

.nav__logo-img {
  width: 44px;
  height: 44px;
  object-fit: contain;
  /* Invert logo for dark bg */
  filter: invert(1);
}

[data-theme='light'] .nav__logo-img {
  filter: none;
}

.nav__logo-text {
  font-family: var(--font-display);
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: -0.02em;
  line-height: 1;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  list-style: none;
}

.nav__links a {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
  letter-spacing: 0.02em;
  transition: color var(--transition-interactive);
}

.nav__links a:hover,
.nav__links a.active {
  color: var(--color-text);
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

/* Theme toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
  transition: color var(--transition-interactive), border-color var(--transition-interactive);
}
.theme-toggle:hover {
  color: var(--color-text);
  border-color: var(--color-text-muted);
}

/* Mobile nav */
.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  width: 28px;
  cursor: pointer;
  padding: var(--space-2);
}
.nav__hamburger span {
  display: block;
  height: 2px;
  background: var(--color-text);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.nav__mobile {
  display: none;
  flex-direction: column;
  gap: var(--space-4);
  padding: var(--space-6) var(--space-4);
  border-top: 1px solid var(--color-divider);
}

.nav__mobile.open {
  display: flex;
}

.nav__mobile a {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
  padding-block: var(--space-2);
}

.nav__mobile a:hover {
  color: var(--color-primary);
}

@media (max-width: 768px) {
  .nav__links,
  .nav__actions .btn {
    display: none;
  }
  .nav__hamburger {
    display: flex;
  }
}

/* ============================================
   FOOTER
   ============================================ */

.site-footer {
  background: var(--color-surface);
  border-top: 1px solid var(--color-divider);
  padding-block: var(--space-16) var(--space-8);
  margin-top: var(--space-32);
}

.footer__grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

.footer__brand p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  margin-top: var(--space-4);
  max-width: 36ch;
}

.footer__col h4 {
  font-family: var(--font-body);
  font-size: var(--text-xs);
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-faint);
  margin-bottom: var(--space-4);
}

.footer__col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer__col ul a {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  text-decoration: none;
}
.footer__col ul a:hover { color: var(--color-primary); }

.footer__bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-8);
  border-top: 1px solid var(--color-divider);
}

.footer__bottom p {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  max-width: none;
}

.footer__social {
  display: flex;
  gap: var(--space-4);
}

.footer__social a {
  color: var(--color-text-faint);
  text-decoration: none;
  transition: color var(--transition-interactive);
}
.footer__social a:hover { color: var(--color-primary); }

@media (max-width: 768px) {
  .footer__grid {
    grid-template-columns: 1fr;
    gap: var(--space-8);
  }
  .footer__bottom {
    flex-direction: column;
    gap: var(--space-4);
    text-align: center;
  }
}