/**
 * Matrilink — Official Digital Hub of Matrizon Inc.
 * Design Identity: OBSIDIAN ATELIER
 *
 * Quiet luxury. Editorial sophistication. Institutional elegance.
 * Architectural minimalism. Premium typography.
 * Strictly text-and-links. Zero external dependencies. Zero fonts downloaded.
 */

:root {
  /* Typographic Stacks (System Fonts Only) */
  --font-serif: Charter, "Bitstream Charter", "Iowan Old Style", "Sitka Text", Cambria, Georgia, "Times New Roman", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SF Mono", Menlo, Consolas, "Liberation Mono", "Courier New", monospace;

  /* Spacious Architectural Rhythm */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Layout Boundaries */
  --max-width: 900px;
  --max-width-wide: 1100px;

  /* SIGNATURE COLOR SYSTEM — Dark Mode (Default Theme) */
  --bg-primary: #151513;        /* Main background */
  --bg-secondary: #22211E;      /* Secondary surface */
  --bg-elevated: #292720;       /* Elevated surface */
  --text-primary: #E9E2D5;      /* Primary text */
  --text-secondary: #AAA398;    /* Secondary text */
  --accent-color: #A58A65;      /* Accent bronze/gold */
  --accent-hover: #C5A983;
  --border-color: #39362F;      /* Borders */
  --border-subtle: #2A2823;
  --border-bronze: #A58A65;

  --text-inverse: #151513;
  --tag-bg: #22211E;
  --tag-border: #39362F;
  --tag-active-bg: #A58A65;
  --tag-active-text: #151513;

  --focus-ring: 2px solid #A58A65;
  --focus-offset: 3px;
}

[data-theme="light"] {
  /* SIGNATURE COLOR SYSTEM — Light Mode */
  --bg-primary: #F3EFE7;        /* Main background */
  --bg-secondary: #FAF8F3;      /* Secondary surface */
  --bg-elevated: #FFFFFF;       /* Elevated surface */
  --text-primary: #24221E;      /* Primary text */
  --text-secondary: #777168;    /* Secondary text */
  --accent-color: #8C704D;      /* Accent warm bronze */
  --accent-hover: #6D5638;
  --border-color: #D9D1C4;      /* Borders */
  --border-subtle: #E8E2D7;
  --border-bronze: #8C704D;

  --text-inverse: #FAF8F3;
  --tag-bg: #EAE4DA;
  --tag-border: #D9D1C4;
  --tag-active-bg: #24221E;
  --tag-active-text: #F3EFE7;

  --focus-ring: 2px solid #8C704D;
  --focus-offset: 3px;
}

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

html {
  font-size: 16px;
  line-height: 1.7;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  overflow-x: hidden;
  word-break: break-word;
}

/* Accessible Skip Link */
.skip-link {
  position: absolute;
  top: -100px;
  left: var(--space-4);
  background: var(--text-primary);
  color: var(--text-inverse);
  padding: var(--space-2) var(--space-5);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  z-index: 1000;
  border: 1px solid var(--accent-color);
  border-radius: 0;
}

.skip-link:focus {
  top: var(--space-4);
  outline: var(--focus-ring);
  outline-offset: var(--focus-offset);
}

/* Keyboard Focus States */
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: var(--focus-ring);
  outline-offset: var(--focus-offset);
}

/* Typography Hierarchy — Obsidian Atelier */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-serif);
  color: var(--text-primary);
  line-height: 1.18;
  font-weight: 500;
  letter-spacing: -0.015em;
}

h1 {
  font-size: clamp(2.25rem, 4.5vw, 3.5rem);
  font-weight: 400;
  margin-bottom: var(--space-5);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.5rem, 2.8vw, 2rem);
  font-weight: 400;
  margin-bottom: var(--space-3);
  letter-spacing: -0.01em;
}

h3 {
  font-size: 1.3rem;
  font-weight: 500;
  margin-bottom: var(--space-2);
}

p {
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  font-size: 1.025rem;
  line-height: 1.75;
  max-width: 68ch;
}

p:last-child {
  margin-bottom: 0;
}

/* Text Links */
a {
  color: var(--text-primary);
  text-decoration: underline;
  text-decoration-color: var(--accent-color);
  text-underline-offset: 4px;
  text-decoration-thickness: 1px;
  cursor: pointer;
  transition: color 0.15s ease, text-decoration-color 0.15s ease;
}

a:hover {
  color: var(--accent-color);
  text-decoration-color: var(--text-primary);
}

/* Monospace Details */
.code-text, code, pre {
  font-family: var(--font-mono);
  font-size: 0.85em;
  letter-spacing: 0.02em;
}

code {
  background-color: var(--bg-secondary);
  color: var(--text-primary);
  padding: 0.15em 0.4em;
  border: 1px solid var(--border-color);
  border-radius: 0;
}

/* Layout Containers */
.site-wrapper {
  flex: 1 0 auto;
  display: flex;
  flex-direction: column;
  width: 100%;
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6);
  padding-right: var(--space-6);
}

.container-wide {
  width: 100%;
  max-width: var(--max-width-wide);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-6);
  padding-right: var(--space-6);
}

main {
  flex: 1 0 auto;
  padding-top: var(--space-10);
  padding-bottom: var(--space-20);
}

/* ==========================================================================
   INSTITUTIONAL MASTHEAD & NAVIGATION (Obsidian Atelier)
   ========================================================================== */
.site-header {
  border-bottom: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  padding-top: var(--space-5);
  padding-bottom: var(--space-4);
}

.masthead-prebar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-2);
  padding-bottom: var(--space-3);
  margin-bottom: var(--space-4);
  border-bottom: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-secondary);
}

.masthead-core {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-bottom: var(--space-5);
}

.brand-block {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.brand-title {
  font-family: var(--font-serif);
  font-size: 1.85rem;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--text-primary);
  text-decoration: none;
  display: inline-flex;
  align-items: baseline;
  gap: 0.1rem;
}

.brand-title:hover {
  text-decoration: none;
  color: var(--accent-color);
}

.brand-word-matri {
  font-family: var(--font-serif);
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.brand-word-link {
  font-family: var(--font-sans);
  font-weight: 300;
  letter-spacing: 0.12em;
  text-transform: lowercase;
  color: var(--accent-color);
  font-size: 1.45rem;
}

.brand-identity-caption {
  font-family: var(--font-mono);
  font-size: 0.725rem;
  color: var(--text-secondary);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

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

/* Institutional Navigation: Clean Horizontal Ledger */
.site-nav {
  margin-top: var(--space-2);
  padding-top: var(--space-3);
  border-top: 1px solid var(--border-subtle);
}

.nav-list {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  gap: var(--space-2) var(--space-6);
  padding: 0;
  margin: 0;
}

.nav-item {
  display: inline-block;
}

.nav-link {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  text-decoration: none;
  padding: var(--space-1) 0;
  display: inline-flex;
  align-items: baseline;
  gap: var(--space-1);
  border-bottom: 1px solid transparent;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.nav-numeral {
  font-size: 0.7em;
  color: var(--accent-color);
  opacity: 0.8;
}

.nav-link:hover {
  color: var(--text-primary);
  border-bottom-color: var(--accent-color);
  text-decoration: none;
}

.nav-link.active,
.nav-link[aria-current="page"] {
  color: var(--text-primary);
  border-bottom: 1px solid var(--accent-color);
}

.nav-link.active .nav-numeral {
  color: var(--accent-color);
  opacity: 1;
}

/* Page Headers — Editorial Monograph Format */
.page-header {
  margin-bottom: var(--space-12);
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--border-color);
  position: relative;
}

.page-header::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 72px;
  height: 2px;
  background-color: var(--accent-color);
}

.page-pretitle {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--accent-color);
  margin-bottom: var(--space-3);
  display: block;
}

.page-description {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 68ch;
}

/* Minimal Rectangular Buttons: Zero Pill */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-2) var(--space-4);
  font-size: 0.775rem;
  font-weight: 500;
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-inverse);
  background-color: var(--accent-color);
  border: 1px solid var(--accent-color);
  border-radius: 0;
  cursor: pointer;
  text-decoration: none;
  line-height: 1.4;
  transition: background-color 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}

.btn:hover {
  background-color: var(--accent-hover);
  border-color: var(--accent-hover);
  color: var(--text-inverse);
  text-decoration: none;
}

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

.btn-secondary:hover {
  background-color: var(--bg-elevated);
  border-color: var(--accent-color);
  color: var(--text-primary);
}

.btn-sm {
  padding: 0.25rem 0.55rem;
  font-size: 0.725rem;
  letter-spacing: 0.06em;
}

/* ==========================================================================
   HOMEPAGE: TYPOGRAPHY-LED INSTITUTIONAL COMPOSITION
   (No generic repetitive rectangular boxes)
   ========================================================================== */
.hero-editorial {
  padding-bottom: var(--space-12);
  margin-bottom: var(--space-12);
  border-bottom: 1px solid var(--border-color);
  position: relative;
}

.hero-editorial::after {
  content: "";
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 90px;
  height: 2px;
  background-color: var(--accent-color);
}

.hero-headline {
  font-size: clamp(2.4rem, 5.2vw, 3.8rem);
  font-weight: 400;
  line-height: 1.12;
  letter-spacing: -0.025em;
  margin-bottom: var(--space-6);
  color: var(--text-primary);
}

.hero-lead-text {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  line-height: 1.75;
  color: var(--text-secondary);
  max-width: 66ch;
  margin-bottom: var(--space-8);
}

/* Institutional Ledger Strip (Asymmetric Metadata Row) */
.institutional-ledger {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  margin-bottom: var(--space-12);
  background-color: var(--bg-secondary);
}

.ledger-cell {
  padding: var(--space-4) var(--space-5);
  border-right: 1px solid var(--border-color);
}

.ledger-cell:last-child {
  border-right: none;
}

.ledger-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-color);
  margin-bottom: 0.35rem;
  display: block;
}

.ledger-value {
  font-family: var(--font-mono);
  font-size: 0.875rem;
  color: var(--text-primary);
  font-weight: 500;
}

/* Editorial Section Structure */
.editorial-section {
  margin-bottom: var(--space-16);
}

.editorial-section-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
  padding-bottom: var(--space-3);
  border-bottom: 1px solid var(--border-color);
}

.section-numeral-title {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
}

.section-numeral {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  letter-spacing: 0.1em;
  color: var(--accent-color);
}

.section-main-title {
  font-family: var(--font-serif);
  font-size: 1.55rem;
  font-weight: 400;
  margin-bottom: 0;
  letter-spacing: -0.01em;
}

.section-view-all {
  font-family: var(--font-mono);
  font-size: 0.775rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--accent-color);
}

/* Mission & Principles: Typography-Led Two-Column Grid */
.principles-ledger {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
  gap: var(--space-6) var(--space-10);
  margin-top: var(--space-6);
}

.principle-entry {
  padding-bottom: var(--space-6);
  border-bottom: 1px solid var(--border-subtle);
}

.principle-head {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
  margin-bottom: var(--space-2);
}

.principle-index {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--accent-color);
}

.principle-title {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--text-primary);
}

.principle-desc {
  font-size: 0.95rem;
  line-height: 1.68;
  color: var(--text-secondary);
}

/* Ecosystem Pillars: Architectural Linear Rows */
.ecosystem-ledger {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
}

.ecosystem-row {
  display: grid;
  grid-template-columns: 240px 1fr;
  padding: var(--space-5) 0;
  border-bottom: 1px solid var(--border-color);
  align-items: baseline;
  gap: var(--space-6);
}

.ecosystem-row-name {
  font-family: var(--font-serif);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--text-primary);
}

.ecosystem-row-focus {
  font-size: 0.95rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* Verified Resources: Tabular Row Architecture */
.resources-ledger {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
}

.resource-row {
  display: grid;
  grid-template-columns: 240px 1fr auto;
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--border-subtle);
  align-items: baseline;
  gap: var(--space-4);
  font-size: 0.9rem;
}

.resource-row-title {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.05em;
  color: var(--text-primary);
  font-weight: 600;
}

.resource-row-desc {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

.resource-row-action a {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  color: var(--accent-color);
}

/* ==========================================================================
   PROJECTS: CURATED INSTITUTIONAL ARCHIVE
   (Fine horizontal separators, archive index, prominent typography)
   ========================================================================== */
.archive-toolbar {
  margin-bottom: var(--space-8);
  padding: var(--space-5);
  background-color: var(--bg-secondary);
  border: 1px solid var(--border-color);
}

.search-input-wrapper {
  display: flex;
  width: 100%;
}

.archive-search-input {
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: 0.95rem;
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 0;
  transition: border-color 0.15s ease;
}

.archive-search-input::placeholder {
  color: var(--text-secondary);
}

.archive-search-input:focus {
  border-color: var(--accent-color);
  background-color: var(--bg-elevated);
}

.archive-status-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-3);
  margin-top: var(--space-3);
  padding-top: var(--space-3);
  border-top: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 0.775rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.archive-counter {
  color: var(--accent-color);
}

.active-filter-indicator {
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
}

.tag-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-3);
}

.tag-cloud-label {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  margin-bottom: 0.25rem;
}

.tag-btn {
  display: inline-block;
  padding: 0.2rem 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  background-color: var(--tag-bg);
  border: 1px solid var(--tag-border);
  border-radius: 0;
  cursor: pointer;
  text-decoration: none;
  transition: all 0.15s ease;
}

.tag-btn:hover {
  border-color: var(--accent-color);
  color: var(--text-primary);
  text-decoration: none;
}

.tag-btn.active {
  background-color: var(--tag-active-bg);
  color: var(--tag-active-text);
  border-color: var(--tag-active-bg);
  font-weight: 600;
}

/* Institutional Archive Records (Linear, Fine Dividers, No generic boxes) */
.archive-stream {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
}

.archive-entry {
  padding: var(--space-8) 0;
  border-bottom: 1px solid var(--border-color);
  position: relative;
  transition: background-color 0.15s ease;
}

.archive-entry:hover {
  background-color: rgba(165, 138, 101, 0.02);
}

.archive-entry-top {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  flex-wrap: wrap;
  gap: var(--space-2) var(--space-4);
  margin-bottom: var(--space-3);
}

.archive-entry-meta {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.archive-entry-num {
  color: var(--accent-color);
  font-weight: 600;
}

.archive-entry-date {
  color: var(--text-secondary);
}

.archive-entry-title {
  font-family: var(--font-serif);
  font-size: clamp(1.4rem, 2.5vw, 1.85rem);
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
  letter-spacing: -0.015em;
}

.archive-entry-desc {
  font-size: 1rem;
  line-height: 1.72;
  color: var(--text-secondary);
  max-width: 68ch;
  margin-bottom: var(--space-4);
}

.archive-entry-tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-bottom: var(--space-4);
}

.archive-entry-links {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-4);
  padding-top: var(--space-3);
  border-top: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

.archive-link-item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
}

.archive-link-item a {
  color: var(--text-primary);
  text-decoration-color: var(--accent-color);
}

/* ==========================================================================
   ANNOUNCEMENTS: REFINED PUBLICATION ARCHIVE
   ========================================================================== */
.announcement-stream {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
}

.announcement-entry {
  padding: var(--space-8) 0;
  border-bottom: 1px solid var(--border-color);
}

.announcement-date-strip {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-color);
  margin-bottom: var(--space-2);
  display: block;
}

.announcement-headline {
  font-family: var(--font-serif);
  font-size: clamp(1.35rem, 2.2vw, 1.7rem);
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
  letter-spacing: -0.01em;
}

.announcement-body {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--text-secondary);
  max-width: 68ch;
}

/* ==========================================================================
   CONTACT DIRECTORY: INSTITUTIONAL REGISTRY
   ========================================================================== */
.contact-division-block {
  margin-bottom: var(--space-12);
}

.contact-division-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 400;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}

.contact-division-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.contact-registry-table {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
}

.contact-registry-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-5);
  border-bottom: 1px solid var(--border-color);
}

.contact-desk-label {
  font-family: var(--font-sans);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-primary);
}

.contact-desk-val {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.85rem;
}

/* ==========================================================================
   SETTINGS & GOVERNANCE: EDITORIAL FORM CONTROLS
   ========================================================================== */
.settings-ledger {
  display: flex;
  flex-direction: column;
  border-top: 1px solid var(--border-color);
}

.settings-entry-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-4);
  padding: var(--space-6) 0;
  border-bottom: 1px solid var(--border-color);
}

.settings-meta-group {
  max-width: 520px;
}

.settings-entry-title {
  font-family: var(--font-serif);
  font-size: 1.25rem;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.settings-entry-desc {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

.theme-controls-group {
  display: inline-flex;
  gap: var(--space-2);
}

/* ==========================================================================
   GLOBAL FOOTER: INSTITUTIONAL COLOPHON
   ========================================================================== */
.site-footer {
  flex-shrink: 0;
  width: 100%;
  border-top: 1px solid var(--border-color);
  background-color: var(--bg-primary);
  padding-top: var(--space-16);
  padding-bottom: var(--space-16);
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: var(--space-10);
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: var(--space-10);
}

.footer-colophon-brand {
  max-width: 380px;
}

.footer-colophon-title {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  font-weight: 500;
  letter-spacing: 0.05em;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.footer-colophon-summary {
  font-size: 0.9rem;
  line-height: 1.68;
  color: var(--text-secondary);
}

.footer-sections-wrapper {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-8) var(--space-12);
}

.footer-section {
  min-width: 150px;
}

.footer-section-title {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--accent-color);
  margin-bottom: var(--space-4);
  font-weight: 600;
}

.footer-links-list {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.footer-link {
  color: var(--text-secondary);
  font-size: 0.85rem;
  text-decoration: none;
  transition: color 0.15s ease;
}

.footer-link:hover {
  color: var(--text-primary);
  text-decoration: underline;
  text-decoration-color: var(--accent-color);
}

.footer-bottom-bar {
  padding-top: var(--space-6);
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--space-4);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  color: var(--text-secondary);
}

/* ==========================================================================
   WELCOME GATE (index.html): QUIET LUXURY ENCLAVE
   ========================================================================== */
.welcome-atelier {
  min-height: 60vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: flex-start;
  padding-top: var(--space-16);
  padding-bottom: var(--space-16);
}

.welcome-kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--accent-color);
  margin-bottom: var(--space-5);
  display: block;
}

.welcome-huge-title {
  font-family: var(--font-serif);
  font-size: clamp(2.8rem, 7vw, 5rem);
  font-weight: 400;
  letter-spacing: -0.03em;
  line-height: 1.05;
  margin-bottom: var(--space-6);
  color: var(--text-primary);
}

.welcome-manifesto {
  font-family: var(--font-serif);
  font-size: 1.35rem;
  line-height: 1.75;
  color: var(--text-secondary);
  max-width: 64ch;
  margin-bottom: var(--space-10);
}

.welcome-meta-ledger {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  width: 100%;
  max-width: 720px;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  margin-bottom: var(--space-10);
  background-color: var(--bg-secondary);
}

.welcome-meta-item {
  padding: var(--space-4) var(--space-5);
  border-right: 1px solid var(--border-color);
}

.welcome-meta-item:last-child {
  border-right: none;
}

.welcome-meta-lbl {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-color);
  margin-bottom: 0.25rem;
  display: block;
}

.welcome-meta-v {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-primary);
}

.btn-enter-archive {
  padding: var(--space-3) var(--space-8);
  font-size: 0.85rem;
  letter-spacing: 0.12em;
}

/* Toast Notice */
.toast-notice {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-8);
  background-color: var(--bg-elevated);
  color: var(--text-primary);
  padding: var(--space-3) var(--space-5);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.05em;
  border-radius: 0;
  border: 1px solid var(--accent-color);
  z-index: 9999;
  opacity: 0;
  transform: translateY(8px);
  transition: opacity 0.2s ease, transform 0.2s ease;
  pointer-events: none;
}

.toast-notice.show {
  opacity: 1;
  transform: translateY(0);
}

/* Back to Top */
.bottom-nav {
  display: flex;
  justify-content: center;
  margin-top: var(--space-12);
  padding-top: var(--space-6);
  border-top: 1px solid var(--border-subtle);
}

.back-to-top-btn {
  font-family: var(--font-mono);
  font-size: 0.775rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-secondary);
  text-decoration: none;
  padding: var(--space-2) var(--space-5);
  border: 1px solid var(--border-color);
  background-color: var(--bg-secondary);
  border-radius: 0;
  cursor: pointer;
  transition: all 0.15s ease;
}

.back-to-top-btn:hover {
  background-color: var(--bg-elevated);
  border-color: var(--accent-color);
  color: var(--text-primary);
  text-decoration: none;
}

/* Empty State */
.empty-state {
  padding: var(--space-16) var(--space-6);
  text-align: center;
  border-top: 1px solid var(--border-color);
  border-bottom: 1px solid var(--border-color);
  color: var(--text-secondary);
  font-family: var(--font-serif);
}

.empty-state-title {
  font-size: 1.35rem;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

/* Mobile-First Adaptations */
@media (max-width: 768px) {
  :root {
    --space-6: 1.15rem;
    --space-8: 1.5rem;
    --space-10: 2rem;
    --space-12: 2.5rem;
    --space-16: 3rem;
  }

  .masthead-prebar {
    flex-direction: column;
    align-items: flex-start;
  }

  .masthead-core {
    flex-direction: column;
    align-items: flex-start;
  }

  .ecosystem-row {
    grid-template-columns: 1fr;
    gap: var(--space-2);
  }

  .resource-row {
    grid-template-columns: 1fr;
    gap: var(--space-2);
  }

  .institutional-ledger,
  .welcome-meta-ledger {
    grid-template-columns: 1fr;
  }

  .ledger-cell,
  .welcome-meta-item {
    border-right: none;
    border-bottom: 1px solid var(--border-color);
  }

  .ledger-cell:last-child,
  .welcome-meta-item:last-child {
    border-bottom: none;
  }

  .principles-ledger {
    grid-template-columns: 1fr;
  }

  .contact-registry-row {
    flex-direction: column;
    align-items: flex-start;
  }

  .settings-entry-row {
    flex-direction: column;
    align-items: flex-start;
  }

  .footer-top {
    flex-direction: column;
  }

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

@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;
  }
}