/* ============================================================
   LAYOUT — Self-Actualization in the Age of Crisis
   SpiritDAO Philosophical Reading Experience
   ============================================================ */

:root {
  /* Brand */
  --color-ritual-green:      #2F5D50;
  --color-ritual-green-dark: #254A40;
  --color-ritual-green-dim:  #E8F1EE;

  /* Page backgrounds */
  --color-bg:            #F0ECE6;
  --color-bg-alt:        #E8E4DC;
  --color-reading-bg:    #FFFFFF;

  /* Text */
  --color-text:          #3A3A3A;
  --color-heading:       #1C1C1C;
  --color-text-muted:    #767676;

  /* Borders */
  --color-border:        #D8D2C8;
  --color-border-light:  #EAE6DF;

  /* Interactive */
  --color-link:          #2F5D50;
  --color-link-hover:    #254A40;

  /* Sidebar / nav active */
  --color-nav-active-bg: #E8F1EE;
  --color-nav-bar:       #2F5D50;

  /* Progress */
  --color-progress:      #2F5D50;

  /* Code */
  --color-code-bg:       #EAE6DF;

  /* Dimensions */
  --sidebar-width:   260px;
  --reading-width:   720px;
  --content-width:   1100px;
  --header-height:   60px;

  /* Spacing (base 8px) */
  --sp-1:  8px;
  --sp-2:  16px;
  --sp-3:  24px;
  --sp-4:  32px;
  --sp-5:  40px;
  --sp-6:  48px;
  --sp-8:  64px;
  --sp-10: 80px;
  --sp-12: 96px;
}

/* ── Reset ─────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { background: var(--color-bg); color: var(--color-text); min-height: 100vh; display: flex; flex-direction: column; }
.site-main { flex: 1; }

/* ── Skip link ──────────────────────────────────────── */
.skip-link {
  position: absolute; top: -40px; left: 0;
  background: var(--color-ritual-green); color: #fff;
  padding: 8px 16px; text-decoration: none; z-index: 200;
  font-size: 0.8125rem; font-family: var(--font-sans);
}
.skip-link:focus { top: 0; }

/* ── Header ─────────────────────────────────────────── */
.site-header {
  position: sticky; top: 0; z-index: 100;
  height: var(--header-height);
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  display: flex; align-items: center;
}
.header-container {
  max-width: var(--content-width); width: 100%;
  margin: 0 auto; padding: 0 var(--sp-5);
  display: flex; justify-content: space-between; align-items: center; gap: var(--sp-3);
}
.site-title {
  font-family: var(--font-sans); font-size: 0.9rem; font-weight: 600;
  color: var(--color-ritual-green); text-decoration: none;
  letter-spacing: 0.01em; flex-shrink: 0;
}
.site-title:hover { color: var(--color-ritual-green-dark); }

.header-nav { display: flex; align-items: center; gap: var(--sp-4); }
.header-nav-link {
  font-family: var(--font-sans); font-size: 0.8125rem; font-weight: 500;
  color: var(--color-text-muted); text-decoration: none; letter-spacing: 0.02em;
  transition: color 0.15s ease;
}
.header-nav-link:hover { color: var(--color-ritual-green); }
.header-nav-link[aria-current="page"] { color: var(--color-ritual-green); }

.header-controls { display: flex; align-items: center; gap: var(--sp-1); }

/* ── Downloads dropdown ───────────────────────────────── */
.nav-dropdown {
  position: relative;
}

.nav-dropdown-toggle {
  cursor: default;
  user-select: none;
}

.nav-dropdown-menu {
  display: none;
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 4px;
  min-width: 130px;
  padding: 4px 0;
  z-index: 100;
}

.nav-dropdown:hover .nav-dropdown-menu {
  display: block;
}

.nav-dropdown-item {
  display: block;
  padding: 7px 14px;
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--color-text-muted);
  text-decoration: none;
  white-space: nowrap;
  transition: color 0.15s ease, background 0.15s ease;
}

.nav-dropdown-item:hover {
  color: var(--color-ritual-green);
  background: var(--color-ritual-green-dim);
}

.dark-mode-toggle {
  background: none; border: none; cursor: pointer;
  padding: 6px; color: var(--color-text-muted); border-radius: 4px;
  display: flex; align-items: center; justify-content: center;
  transition: color 0.15s ease, background 0.15s ease;
}
.dark-mode-toggle:hover { color: var(--color-ritual-green); background: var(--color-ritual-green-dim); }

.mobile-menu-toggle {
  display: none; background: none; border: none;
  cursor: pointer; flex-direction: column; gap: 5px;
  padding: 6px; border-radius: 4px;
}
.mobile-menu-toggle span {
  display: block; width: 22px; height: 1.5px;
  background: var(--color-text-muted); transition: all 0.25s ease;
}

.hidden { display: none; }

/* ── Reading progress ───────────────────────────────── */
.reading-progress-bar {
  position: fixed; top: 0; left: 0;
  width: 0%; height: 2px;
  background: var(--color-progress);
  z-index: 200; transition: width 0.1s linear;
}

/* ── Chapter two-column layout ──────────────────────── */
.chapter-layout {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr;
  max-width: calc(var(--sidebar-width) + var(--reading-width) + 160px);
  margin: 0 auto;
  padding: var(--sp-10) var(--sp-5) var(--sp-12);
  gap: var(--sp-8);
  align-items: start;
}

/* ── Sidebar ─────────────────────────────────────────── */
.toc-sidebar {
  position: sticky;
  top: calc(var(--header-height) + var(--sp-5));
  max-height: calc(100vh - var(--header-height) - var(--sp-8));
  overflow-y: auto;
  width: var(--sidebar-width);
  scrollbar-width: thin;
  scrollbar-color: var(--color-border) transparent;
}
.toc-sidebar::-webkit-scrollbar { width: 3px; }
.toc-sidebar::-webkit-scrollbar-track { background: transparent; }
.toc-sidebar::-webkit-scrollbar-thumb { background: var(--color-border); border-radius: 2px; }

.toc-header {
  display: flex; justify-content: space-between; align-items: center;
  margin-bottom: var(--sp-3); padding-bottom: var(--sp-1);
  border-bottom: 1px solid var(--color-border);
}
.toc-header h2 {
  font-family: var(--font-sans); font-size: 0.625rem; font-weight: 700;
  color: var(--color-text-muted); text-transform: uppercase;
  letter-spacing: 0.14em; margin: 0;
}
.toc-close {
  display: none; background: none; border: none;
  font-size: 1.25rem; cursor: pointer;
  color: var(--color-text-muted); padding: 0; line-height: 1;
}

/* ── Reading area ────────────────────────────────────── */
.chapter-content {
  min-width: 0;
  max-width: var(--reading-width);
  background: var(--color-reading-bg);
  padding: var(--sp-10);
  border: 1px solid var(--color-border-light);
}

/* ── Chapter prev/next ───────────────────────────────── */
.chapter-navigation {
  display: grid; grid-template-columns: 1fr 1fr; gap: var(--sp-2);
  margin-top: var(--sp-10); padding-top: var(--sp-5);
  border-top: 1px solid var(--color-border);
}
.nav-link {
  display: flex; flex-direction: column; gap: 4px;
  padding: var(--sp-3) var(--sp-3);
  border: 1px solid var(--color-border);
  text-decoration: none; color: var(--color-text);
  transition: border-color 0.15s ease, background 0.15s ease;
}
.nav-link:hover { border-color: var(--color-ritual-green); background: var(--color-ritual-green-dim); }
.nav-label {
  font-family: var(--font-sans); font-size: 0.625rem; font-weight: 700;
  color: var(--color-text-muted); text-transform: uppercase; letter-spacing: 0.1em;
}
.nav-title {
  font-family: var(--font-sans); font-size: 0.875rem; font-weight: 600;
  color: var(--color-heading); line-height: 1.35;
}
.nav-next { text-align: right; }

/* ── Footer ──────────────────────────────────────────── */
.site-footer {
  margin-top: auto; padding: var(--sp-5) 0;
  border-top: 1px solid var(--color-border);
  background: var(--color-bg-alt);
}
.footer-container {
  max-width: var(--content-width); margin: 0 auto; padding: 0 var(--sp-5);
  text-align: center; font-family: var(--font-sans);
  font-size: 0.75rem; color: var(--color-text-muted); line-height: 2;
}
.footer-container a { color: var(--color-ritual-green); text-decoration: none; }
.footer-container a:hover { text-decoration: underline; }

/* ── Responsive 1024px ──────────────────────────────── */
@media (max-width: 1024px) {
  :root { --sidebar-width: 220px; }
  .chapter-layout { padding: var(--sp-8) var(--sp-4); gap: var(--sp-6); }
  .chapter-content { padding: var(--sp-8); }
}

/* ── Responsive 768px ───────────────────────────────── */
@media (max-width: 768px) {
  .mobile-menu-toggle { display: flex; }
  .header-nav { display: none; }
  .header-container { padding: 0 var(--sp-2); }

  .chapter-layout {
    grid-template-columns: 1fr;
    padding: var(--sp-4) var(--sp-2);
    max-width: 100%;
  }

  .toc-sidebar {
    position: fixed; top: 0; left: -100%; width: 300px;
    height: 100vh; max-height: 100vh; z-index: 150;
    background: var(--color-bg); border-right: 1px solid var(--color-border);
    padding: var(--sp-5); transition: left 0.25s ease;
  }
  .toc-sidebar.open { left: 0; }
  .toc-close { display: block; }

  .chapter-content { padding: var(--sp-4) var(--sp-3); border: none; }
  .chapter-navigation { grid-template-columns: 1fr; }
  .nav-next { text-align: left; }
}