/*
 * Quin OS 2 — Technical Architecture & Research Specification
 * Academic / Systems Research Paper Design System
 * Formatted for Inbora Studio & Dr Chamyoung (Alok)
 * Inspired by USENIX OSDI, ACM SIGOPS, Bell Labs, and MIT PDOS publications.
 */

:root {
  --bg-page: #FFFFFF;
  --bg-subtle: #F8F9FA;
  --bg-code: #F4F5F7;
  --text-main: #111827;
  --text-muted: #4B5563;
  --text-dim: #6B7280;
  --rule-strong: #111827;
  --rule-medium: #D1D5DB;
  --rule-light: #E5E7EB;
  --accent-ink: #0F172A;
  --link-color: #1D4ED8;
  --font-serif: "Charter", "Bitstream Charter", "Sitka Text", "Cambria", "Georgia", serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas, Monaco, "Liberation Mono", monospace;
  --max-width: 960px;
}

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

html {
  font-size: 17px;
  background-color: var(--bg-page);
  color: var(--text-main);
  font-family: var(--font-serif);
  line-height: 1.7;
  scroll-behavior: smooth;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body {
  background: var(--bg-page);
  color: var(--text-main);
  padding: 0 1.25rem 4rem 1.25rem;
}

/* ═════════════════════════════════════════════════════════════════════════
 * Academic Paper Layout
 * ═════════════════════════════════════════════════════════════════════════ */
.paper-container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding-top: 3.0rem;
}

/* Top metadata banner */
.paper-meta-header {
  border-bottom: 2px solid var(--rule-strong);
  padding-bottom: 1.5rem;
  margin-bottom: 2.5rem;
}

.paper-journal-tag {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 0.5rem;
}

.paper-title {
  font-size: 2.25rem;
  font-weight: 700;
  line-height: 1.25;
  color: var(--text-main);
  margin-bottom: 1.0rem;
  letter-spacing: -0.015em;
}

.paper-subtitle {
  font-size: 1.25rem;
  font-weight: 400;
  font-style: italic;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
  line-height: 1.45;
}

.paper-authors {
  font-family: var(--font-sans);
  font-size: 0.95rem;
  line-height: 1.5;
  color: var(--text-main);
  margin-bottom: 0.5rem;
}

.paper-authors strong {
  font-weight: 600;
}

.paper-institution {
  font-family: var(--font-sans);
  font-size: 0.88rem;
  color: var(--text-muted);
}

.paper-dates {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-top: 0.4rem;
}

/* Abstract Box */
.paper-abstract {
  background: var(--bg-subtle);
  border-left: 3px solid var(--accent-ink);
  padding: 1.5rem 1.75rem;
  margin: 2.5rem 0;
  font-size: 0.96rem;
  line-height: 1.65;
}

.paper-abstract-title {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-main);
  margin-bottom: 0.6rem;
}

/* Quick Navigation Bar */
.paper-nav {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--rule-medium);
  padding: 0.65rem 0;
  margin-bottom: 2.5rem;
  z-index: 100;
}

.paper-nav-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.0rem;
  font-family: var(--font-sans);
  font-size: 0.84rem;
  overflow-x: auto;
  white-space: nowrap;
}

.paper-nav-links {
  display: flex;
  gap: 1.25rem;
}

.paper-nav-links a {
  color: var(--text-muted);
  text-decoration: none;
  font-weight: 500;
}

.paper-nav-links a:hover {
  color: var(--text-main);
  text-decoration: underline;
}

.paper-quick-search {
  border: 1px solid var(--rule-medium);
  border-radius: 4px;
  padding: 0.25rem 0.6rem;
  font-size: 0.8rem;
  font-family: var(--font-sans);
  outline: none;
  width: 180px;
}

.paper-quick-search:focus {
  border-color: var(--text-main);
}

/* Typography Hierarchy */
h2.sec-heading {
  font-size: 1.55rem;
  font-weight: 700;
  color: var(--text-main);
  margin: 3.25rem 0 1.0rem 0;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--rule-strong);
  letter-spacing: -0.01em;
}

h3.sec-subheading {
  font-size: 1.2rem;
  font-weight: 600;
  color: var(--text-main);
  margin: 2.0rem 0 0.65rem 0;
}

h4.sec-tertiary {
  font-size: 1.02rem;
  font-weight: 600;
  font-family: var(--font-sans);
  color: var(--text-main);
  margin: 1.5rem 0 0.5rem 0;
}

p {
  margin-bottom: 1.2rem;
  text-align: justify;
}

p.lead {
  font-size: 1.05rem;
  line-height: 1.7;
}

a {
  color: var(--link-color);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

ul, ol {
  margin: 0.75rem 0 1.25rem 1.75rem;
  font-size: 0.96rem;
}

li {
  margin-bottom: 0.4rem;
}

/* ═════════════════════════════════════════════════════════════════════════
 * Academic Tables (Formal Booktabs Style)
 * ═════════════════════════════════════════════════════════════════════════ */
.table-container {
  margin: 2.0rem 0 2.5rem 0;
  overflow-x: auto;
}

table.academic-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-sans);
  font-size: 0.86rem;
  line-height: 1.5;
  border-top: 2px solid var(--rule-strong);
  border-bottom: 2px solid var(--rule-strong);
}

table.academic-table th, 
table.academic-table td {
  padding: 0.65rem 0.85rem;
  text-align: left;
  vertical-align: top;
}

table.academic-table th {
  font-weight: 600;
  border-bottom: 1px solid var(--rule-strong);
  background: var(--bg-subtle);
  color: var(--text-main);
}

table.academic-table tbody tr {
  border-bottom: 1px solid var(--rule-light);
}

table.academic-table tbody tr:last-child {
  border-bottom: none;
}

table.academic-table td strong {
  font-weight: 600;
}

.table-caption {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  color: var(--text-dim);
  margin-bottom: 0.5rem;
  font-weight: 500;
}

/* ═════════════════════════════════════════════════════════════════════════
 * Code Listings & Assembly Blocks
 * ═════════════════════════════════════════════════════════════════════════ */
pre {
  background: var(--bg-code);
  border: 1px solid var(--rule-medium);
  border-radius: 4px;
  padding: 1.0rem 1.2rem;
  margin: 1.25rem 0 1.75rem 0;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
  color: #1E293B;
}

code {
  font-family: var(--font-mono);
  font-size: 0.85em;
  background: var(--bg-code);
  padding: 0.15rem 0.35rem;
  border-radius: 3px;
  border: 1px solid var(--rule-light);
  color: #0F172A;
}

pre code {
  background: none;
  padding: 0;
  border: none;
  font-size: inherit;
  color: inherit;
}

.listing-caption {
  font-family: var(--font-sans);
  font-size: 0.8rem;
  color: var(--text-dim);
  margin-top: -1.25rem;
  margin-bottom: 1.5rem;
  font-style: italic;
}

/* Memory Map / Diagram ASCII Figures */
.figure-box {
  background: var(--bg-subtle);
  border: 1px solid var(--rule-medium);
  border-radius: 4px;
  padding: 1.25rem;
  margin: 2.0rem 0;
}

.figure-box pre {
  background: none;
  border: none;
  padding: 0;
  margin: 0;
  font-size: 0.8rem;
  color: #0F172A;
}

.figure-caption {
  font-family: var(--font-sans);
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-main);
  margin-top: 0.75rem;
  padding-top: 0.5rem;
  border-top: 1px solid var(--rule-light);
}

/* ═════════════════════════════════════════════════════════════════════════
 * Case Study / Incident Report Callouts
 * ═════════════════════════════════════════════════════════════════════════ */
.callout-box {
  background: var(--bg-subtle);
  border-left: 3px solid #334155;
  padding: 1.0rem 1.25rem;
  margin: 1.5rem 0;
  font-size: 0.92rem;
}

.callout-header {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #0F172A;
  margin-bottom: 0.4rem;
}

/* ═════════════════════════════════════════════════════════════════════════
 * 5-Year Research Timeline (Academic Chronology)
 * ═════════════════════════════════════════════════════════════════════════ */
.chronology-list {
  list-style: none;
  margin: 1.5rem 0 2.5rem 0;
  padding: 0;
}

.chronology-item {
  border-left: 2px solid var(--rule-strong);
  padding: 0.25rem 0 1.5rem 1.5rem;
  position: relative;
}

.chronology-item::before {
  content: "";
  position: absolute;
  left: -5px;
  top: 0.4rem;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--rule-strong);
}

.chronology-item:last-child {
  border-left-color: transparent;
}

.chronology-year {
  font-family: var(--font-sans);
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-main);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.25rem;
}

.chronology-title {
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 0.4rem;
}

.chronology-desc {
  font-size: 0.92rem;
  color: var(--text-muted);
  line-height: 1.6;
}

/* ═════════════════════════════════════════════════════════════════════════
 * BibTeX Citation Block
 * ═════════════════════════════════════════════════════════════════════════ */
.bibtex-box {
  background: var(--bg-code);
  border: 1px solid var(--rule-medium);
  border-radius: 4px;
  padding: 1.0rem 1.25rem;
  margin: 1.5rem 0;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.45;
  color: #1E293B;
  overflow-x: auto;
}

/* Footer */
.paper-footer {
  border-top: 1px solid var(--rule-medium);
  padding-top: 2.0rem;
  margin-top: 4.0rem;
  font-family: var(--font-sans);
  font-size: 0.84rem;
  color: var(--text-dim);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.0rem;
}

/* Responsive */
@media (max-width: 768px) {
  html {
    font-size: 16px;
  }
  .paper-title {
    font-size: 1.85rem;
  }
  .paper-nav-links {
    display: none;
  }
  table.academic-table {
    font-size: 0.78rem;
  }
}