/* ML Meanders - Distill-Style Layout System */

/* ============================================
   Layout Width Classes
   Inspired by Distill.pub's responsive grid
   ============================================ */

/* Base content widths */
:root {
  --width-body: 65ch;     /* ~650px - comfortable reading */
  --width-middle: 816px;  /* Wider for figures */
  --width-page: 984px;    /* Full content width */
  --width-screen: 100%;   /* Edge to edge */

  --gutter: 24px;
  --sidenote-width: 280px;
  --sidenote-gap: 40px;
}

/* ============================================
   Width Classes
   ============================================ */

/* Standard body text width - optimal for reading */
.l-body {
  max-width: var(--width-body);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* Middle width - for diagrams and figures */
.l-middle {
  max-width: var(--width-middle);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* Page width - full content area */
.l-page {
  max-width: var(--width-page);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* Screen width - edge to edge */
.l-screen {
  width: 100%;
  max-width: none;
  margin-left: 0;
  margin-right: 0;
  padding-left: 0;
  padding-right: 0;
}

/* Outset variants - break out of parent container */
.l-body-outset {
  max-width: calc(var(--width-body) + 100px);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

.l-middle-outset {
  max-width: calc(var(--width-middle) + 100px);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter);
}

/* ============================================
   Header Layout
   ============================================ */
.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border-subtle);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.nav-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 64px;
}

.site-logo {
  font-family: var(--font-sans);
  font-weight: var(--font-weight-semibold);
  font-size: var(--font-size-lg);
  color: var(--color-text);
  text-decoration: none;
}

.site-logo:hover {
  color: var(--color-accent);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  font-family: var(--font-sans);
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-medium);
  color: var(--color-text-muted);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--color-text);
}

/* Theme toggle button */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  padding: 0;
  border: none;
  background: none;
  cursor: pointer;
  color: var(--color-text-muted);
  border-radius: var(--radius-md);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.theme-toggle:hover {
  color: var(--color-text);
  background-color: var(--color-bg-subtle);
}

/* Show/hide sun/moon icons based on theme */
[data-theme="light"] .icon-moon {
  display: none;
}

[data-theme="dark"] .icon-sun {
  display: none;
}

/* ============================================
   Footer Layout
   ============================================ */
.site-footer {
  margin-top: auto;
  padding: var(--space-3xl) var(--gutter);
  background-color: var(--color-bg-subtle);
  border-top: 1px solid var(--color-border-subtle);
}

.footer-container {
  display: flex;
  flex-direction: column;
  gap: var(--space-lg);
}

.footer-content {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: var(--space-md);
}

.footer-tagline {
  font-style: italic;
  color: var(--color-text-muted);
  margin: 0;
}

.footer-nav {
  display: flex;
  gap: var(--space-lg);
}

.footer-link {
  font-family: var(--font-sans);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
}

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

.footer-copyright {
  font-size: var(--font-size-sm);
  color: var(--color-text-faint);
  margin: 0;
}

.footer-copyright a {
  color: var(--color-text-muted);
}

/* ============================================
   Post Layout with Sidenote Column
   ============================================ */
.post-content-wrapper {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--gutter);
  max-width: var(--width-page);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

/* Desktop: add sidenote column */
@media (min-width: 1100px) {
  .post-content-wrapper {
    grid-template-columns: 200px 1fr 300px;
    gap: var(--sidenote-gap);
    padding: 0 var(--gutter);
  }

  .toc-sidebar {
    position: sticky;
    top: calc(64px + var(--space-xl));
    justify-self: end;
    align-self: start;
    max-height: calc(100vh - 64px - var(--space-3xl));
    overflow-y: auto;
  }

  .post-body {
    max-width: var(--width-body);
    padding: 0;
    overflow-x: hidden;
  }

  .sidenote-column {
    position: relative;
  }
}

/* Hide ToC sidebar on mobile */
@media (max-width: 1099px) {
  .toc-sidebar {
    display: none;
  }

  .sidenote-column {
    display: none;
  }

  .post-body {
    max-width: var(--width-body);
    margin: 0 auto;
  }
}

/* ============================================
   Responsive Breakpoints
   ============================================ */
@media (max-width: 768px) {
  :root {
    --gutter: 20px;
  }

  .nav-container {
    height: 56px;
  }

  .nav-links {
    gap: var(--space-md);
  }

  h1 {
    font-size: var(--font-size-3xl);
  }

  h2 {
    font-size: var(--font-size-xl);
  }

  .post-title {
    font-size: var(--font-size-2xl);
  }
}

@media (max-width: 480px) {
  :root {
    --gutter: 16px;
  }

  .footer-content {
    flex-direction: column;
    align-items: flex-start;
  }
}