:root {
  --khu-red: #a40f16;
  --khu-red-dark: #7a0b10;
  --khu-blue: #0d326f;
  --khu-gold: #c0a353;
  --khu-gray: #717171;

  --bg-body: #f4f6fb;
  --bg-surface: #ffffff;
  --bg-surface-alt: #eef1f8;
  --bg-code: #1e1e2e;
  --bg-navbar: var(--khu-red);
  --bg-hero: linear-gradient(135deg, var(--khu-red) 0%, var(--khu-blue) 100%);

  --text-primary: #1a1a2e;
  --text-secondary: #5a6278;
  --text-muted: #8b93a7;
  --text-on-hero: #ffffff;
  --text-code: #cdd6f4;

  --border-color: #dde2ef;
  --shadow-sm: 0 2px 8px rgba(13, 50, 111, 0.06);
  --shadow-md: 0 8px 24px rgba(13, 50, 111, 0.1);
  --shadow-lg: 0 16px 48px rgba(13, 50, 111, 0.14);

  --accent: var(--khu-blue);
  --accent-soft: rgba(13, 50, 111, 0.08);
  --toc-active: var(--khu-red);
  --radius: 12px;
  --radius-lg: 16px;
  --nav-height: 64px;
  --sidebar-width: 280px;
  --transition: 0.25s ease;
}

[data-theme="dark"] {
  --bg-body: #0f1117;
  --bg-surface: #1a1d27;
  --bg-surface-alt: #242836;
  --bg-code: #0d0f14;
  --bg-navbar: #1a1d27;
  --bg-hero: linear-gradient(135deg, #3d1014 0%, #0a1f45 100%);

  --text-primary: #e8eaf0;
  --text-secondary: #a8afc2;
  --text-muted: #6b7289;
  --text-code: #bac2de;

  --border-color: #2e3345;
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 48px rgba(0, 0, 0, 0.5);

  --accent-soft: rgba(192, 163, 83, 0.12);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--nav-height) + 24px);
}

body {
  margin: 0;
  font-family: "Pretendard Variable", Pretendard, -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, "Noto Sans KR", sans-serif;
  background: var(--bg-body);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background var(--transition), color var(--transition);
}

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

a:hover {
  color: var(--khu-red);
}

.skip-link {
  position: absolute;
  top: -100%;
  left: 16px;
  z-index: 9999;
  padding: 8px 16px;
  background: var(--khu-gold);
  color: #1a1a2e;
  border-radius: 0 0 8px 8px;
  font-weight: 600;
}

.skip-link:focus {
  top: 0;
}

/* Navbar */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1030;
  height: var(--nav-height);
  background: var(--bg-navbar);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  backdrop-filter: blur(12px);
}

.site-nav .container-fluid {
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1400px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  color: #fff !important;
  font-weight: 700;
  font-size: 1.15rem;
}

.navbar-brand i {
  color: var(--khu-gold);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-link-ext {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.45rem 1rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.12);
  color: #fff !important;
  font-size: 0.875rem;
  transition: background var(--transition);
}

.nav-link-ext:hover {
  background: rgba(255, 255, 255, 0.22);
  color: #fff !important;
}

.btn-theme,
.btn-toc-mobile {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.08);
  color: #fff;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-theme:hover,
.btn-toc-mobile:hover {
  background: rgba(255, 255, 255, 0.18);
}

.btn-toc-mobile {
  display: none;
}

[data-theme="dark"] .site-nav {
  border-bottom-color: var(--border-color);
}

/* Hero */
.hero {
  margin-top: var(--nav-height);
  background: var(--bg-hero);
  color: var(--text-on-hero);
  padding: 3.5rem 1.5rem 3rem;
}

.hero-inner {
  max-width: 1400px;
  margin: 0 auto;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.35rem 0.85rem;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.15);
  font-size: 0.8rem;
  font-weight: 500;
  margin-bottom: 1rem;
}

.hero h1 {
  font-size: clamp(1.75rem, 4vw, 2.75rem);
  font-weight: 800;
  margin: 0 0 0.5rem;
  letter-spacing: -0.02em;
}

.hero .lead {
  font-size: 1.1rem;
  opacity: 0.9;
  margin-bottom: 1.5rem;
  max-width: 600px;
}

.contact-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1.25rem;
  background: rgba(255, 255, 255, 0.12);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius);
  font-size: 0.95rem;
}

.contact-chip a {
  color: var(--khu-gold);
  font-weight: 600;
}

.contact-chip a:hover {
  color: #fff;
}

.hero-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
  margin-top: 2rem;
}

.hero-stat {
  display: flex;
  flex-direction: column;
}

.hero-stat-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--khu-gold);
}

.hero-stat-label {
  font-size: 0.8rem;
  opacity: 0.75;
}

/* Layout */
.page-layout {
  display: grid;
  grid-template-columns: var(--sidebar-width) 1fr;
  gap: 2rem;
  max-width: 1400px;
  margin: 0 auto;
  padding: 2rem 1.5rem 4rem;
}

/* Sidebar TOC */
.sidebar {
  position: sticky;
  top: calc(var(--nav-height) + 24px);
  align-self: start;
  max-height: calc(100vh - var(--nav-height) - 48px);
  overflow-y: auto;
}

.sidebar-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
}

.sidebar-title {
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

.sidebar-close {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-surface-alt);
  color: var(--text-secondary);
  cursor: pointer;
}

.toc-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.toc-list > li {
  margin-bottom: 0.25rem;
}

.toc-list a {
  display: block;
  padding: 0.4rem 0.75rem;
  border-radius: 8px;
  color: var(--text-secondary);
  font-size: 0.875rem;
  transition: all var(--transition);
  border-left: 3px solid transparent;
}

.toc-list a:hover {
  background: var(--accent-soft);
  color: var(--text-primary);
}

.toc-list a.active {
  background: var(--accent-soft);
  color: var(--toc-active);
  font-weight: 600;
  border-left-color: var(--toc-active);
}

.toc-list ul {
  list-style: none;
  padding: 0 0 0 0.75rem;
  margin: 0.15rem 0 0.5rem;
}

.toc-list ul a {
  font-size: 0.8rem;
  padding: 0.3rem 0.65rem;
}

/* Main content */
.content section {
  margin-bottom: 3rem;
  scroll-margin-top: calc(var(--nav-height) + 24px);
}

.section-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-sm);
  margin-bottom: 1.5rem;
}

.section-card h2 {
  font-size: 1.5rem;
  font-weight: 800;
  margin: 0 0 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 2px solid var(--khu-red);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.section-card h2 i {
  color: var(--khu-red);
}

.section-card h3 {
  font-size: 1.15rem;
  font-weight: 700;
  margin: 2rem 0 1rem;
  color: var(--text-primary);
}

.section-card h3:first-of-type {
  margin-top: 0;
}

.section-card h4 {
  font-size: 1rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
  color: var(--accent);
}

.section-card p,
.section-card li {
  color: var(--text-secondary);
}

.info-callout {
  display: flex;
  gap: 1rem;
  padding: 1rem 1.25rem;
  background: var(--accent-soft);
  border-left: 4px solid var(--khu-blue);
  border-radius: 0 var(--radius) var(--radius) 0;
  margin: 1.25rem 0;
}

.info-callout.warning {
  background: rgba(164, 15, 22, 0.08);
  border-left-color: var(--khu-red);
}

.info-callout i {
  font-size: 1.25rem;
  color: var(--khu-blue);
  flex-shrink: 0;
}

.info-callout.warning i {
  color: var(--khu-red);
}

/* Spec cards */
.spec-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
  margin: 1.5rem 0;
}

.spec-card {
  background: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  padding: 1.5rem;
  transition: transform var(--transition), box-shadow var(--transition);
}

.spec-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.spec-card-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.spec-icon {
  width: 48px;
  height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  font-size: 1.35rem;
}

.spec-icon.login {
  background: rgba(13, 50, 111, 0.12);
  color: var(--khu-blue);
}

.spec-icon.gpu {
  background: rgba(164, 15, 22, 0.12);
  color: var(--khu-red);
}

.spec-card h4 {
  margin: 0;
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-primary);
}

.spec-card .node-tag {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.spec-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.spec-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 0.4rem 0;
  font-size: 0.875rem;
  border-bottom: 1px dashed var(--border-color);
}

.spec-list li:last-child {
  border-bottom: none;
}

.spec-list i {
  color: var(--khu-gold);
  margin-top: 0.15rem;
}

/* Account cards */
.account-grid {
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.account-note {
  display: flex;
  gap: 0.65rem;
  padding: 0.85rem 1rem;
  margin: 1rem 0 0;
  background: rgba(13, 50, 111, 0.06);
  border-radius: 8px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

[data-theme="dark"] .account-note {
  background: rgba(13, 50, 111, 0.15);
}

.account-note i {
  color: var(--khu-blue);
  flex-shrink: 0;
  margin-top: 0.1rem;
}

.account-period-list {
  list-style: none;
  padding: 0;
  margin: 0.75rem 0 0;
}

.account-period-list li {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding: 0.35rem 0;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.account-period-list .semester-tag {
  display: inline-block;
  min-width: 3.5rem;
  padding: 0.15rem 0.5rem;
  background: var(--accent-soft);
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--khu-blue);
  text-align: center;
}

[data-theme="dark"] .account-period-list .semester-tag {
  color: var(--khu-gold);
}

.account-apply-box {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px dashed var(--border-color);
}

.account-apply-box p {
  margin-bottom: 0.75rem;
  font-size: 0.875rem;
}

.account-card {
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  overflow: hidden;
  transition: box-shadow var(--transition);
}

.account-card:hover {
  box-shadow: var(--shadow-md);
}

.account-card-header {
  padding: 1rem 1.25rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.account-card.student .account-card-header {
  background: rgba(13, 50, 111, 0.08);
  color: var(--khu-blue);
}

.account-card.research .account-card-header {
  background: rgba(192, 163, 83, 0.15);
  color: #8a7330;
}

[data-theme="dark"] .account-card.research .account-card-header {
  color: var(--khu-gold);
}

.account-card-body {
  padding: 1.25rem;
  background: var(--bg-surface-alt);
}

/* Code blocks */
.code-block {
  position: relative;
  margin: 1rem 0;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.code-block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.5rem 1rem;
  background: #2a2a3c;
  font-size: 0.75rem;
  color: #a6adc8;
}

.code-block-header .dots {
  display: flex;
  gap: 6px;
}

.code-block-header .dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}

.code-block-header .dot.red { background: #f38ba8; }
.code-block-header .dot.yellow { background: #f9e2af; }
.code-block-header .dot.green { background: #a6e3a1; }

.btn-copy {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.25rem 0.65rem;
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.06);
  color: #cdd6f4;
  font-size: 0.7rem;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-copy:hover {
  background: rgba(255, 255, 255, 0.12);
}

.btn-copy.copied {
  color: #a6e3a1;
  border-color: #a6e3a1;
}

.code-block pre {
  margin: 0;
  padding: 1rem 1.25rem;
  background: var(--bg-code);
  color: var(--text-code);
  font-family: "JetBrains Mono", "Fira Code", "Cascadia Code", Consolas, monospace;
  font-size: 0.82rem;
  line-height: 1.6;
  overflow-x: auto;
  white-space: pre;
}

.code-block .hl-info { color: #89b4fa; }
.code-block .hl-muted { color: #6c7086; }
.code-block .hl-prompt { color: #a6e3a1; }

/* Slurm tabs */
.slurm-panel {
  margin-top: 1.5rem;
}

.slurm-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.75rem;
}

.slurm-tab {
  padding: 0.5rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 999px;
  background: var(--bg-surface-alt);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
}

.slurm-tab:hover {
  border-color: var(--khu-blue);
  color: var(--khu-blue);
}

.slurm-tab.active {
  background: var(--khu-blue);
  border-color: var(--khu-blue);
  color: #fff;
}

.slurm-search {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.slurm-search input {
  flex: 1;
  padding: 0.6rem 1rem 0.6rem 2.5rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  background: var(--bg-surface-alt);
  color: var(--text-primary);
  font-size: 0.875rem;
  outline: none;
  transition: border-color var(--transition);
}

.slurm-search input:focus {
  border-color: var(--khu-blue);
}

.slurm-search-wrap {
  position: relative;
  flex: 1;
}

.slurm-search-wrap i {
  position: absolute;
  left: 0.85rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
}

.slurm-tab-pane {
  display: none;
}

.slurm-tab-pane.active {
  display: block;
}

.slurm-tab-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

.slurm-tab-desc code {
  padding: 0.1rem 0.35rem;
  background: var(--accent-soft);
  border-radius: 4px;
  font-size: 0.8rem;
}

.slurm-table-wrap {
  overflow-x: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
}

.slurm-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
}

.slurm-table th {
  background: var(--bg-surface-alt);
  padding: 0.75rem 1rem;
  text-align: left;
  font-weight: 600;
  color: var(--text-primary);
  border-bottom: 2px solid var(--border-color);
  white-space: nowrap;
}

.slurm-table td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-secondary);
  vertical-align: top;
}

.slurm-table tr:last-child td {
  border-bottom: none;
}

.slurm-table tr.hidden {
  display: none;
}

.slurm-table code {
  display: inline-block;
  padding: 0.15rem 0.45rem;
  background: var(--accent-soft);
  border-radius: 4px;
  font-size: 0.8rem;
  color: var(--khu-blue);
  white-space: nowrap;
}

[data-theme="dark"] .slurm-table code {
  color: var(--khu-gold);
}

.slurm-table .cmd-name {
  font-weight: 700;
  color: var(--khu-red);
}

/* Example tabs */
.example-tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 0;
}

.example-tab {
  padding: 0.65rem 1.25rem;
  border: none;
  background: none;
  color: var(--text-muted);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: all var(--transition);
}

.example-tab:hover {
  color: var(--text-primary);
}

.example-tab.active {
  color: var(--khu-red);
  border-bottom-color: var(--khu-red);
}

.example-pane {
  display: none;
  padding-top: 1rem;
}

.example-pane.active {
  display: block;
}

.download-link {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.3rem 0.75rem;
  background: var(--accent-soft);
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
}

.download-link:hover {
  background: rgba(13, 50, 111, 0.15);
}

.feature-list {
  padding-left: 0;
  list-style: none;
}

.feature-list li {
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
  padding: 0.35rem 0;
}

.feature-list i {
  color: var(--khu-gold);
  margin-top: 0.2rem;
}

.ext-links {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 1rem 0;
}

.ext-link-card {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1rem;
  background: var(--bg-surface-alt);
  border: 1px solid var(--border-color);
  border-radius: var(--radius);
  font-size: 0.875rem;
  font-weight: 500;
  transition: all var(--transition);
}

.ext-link-card:hover {
  border-color: var(--khu-blue);
  box-shadow: var(--shadow-sm);
}

/* Footer */
.site-footer {
  background: var(--khu-red);
  color: rgba(255, 255, 255, 0.85);
  padding: 2rem 1.5rem;
  text-align: center;
  font-size: 0.875rem;
}

[data-theme="dark"] .site-footer {
  background: #1a1d27;
  border-top: 1px solid var(--border-color);
}

.site-footer a {
  color: var(--khu-gold);
}

/* Back to top */
.btn-back-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border: none;
  border-radius: 12px;
  background: var(--khu-red);
  color: #fff;
  font-size: 1.1rem;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition);
  z-index: 100;
}

.btn-back-top.visible {
  opacity: 1;
  visibility: visible;
}

.btn-back-top:hover {
  background: var(--khu-red-dark);
  transform: translateY(-2px);
}

/* Mobile sidebar overlay */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1040;
}

.sidebar-overlay.open {
  display: block;
}

/* Responsive */
@media (max-width: 991px) {
  .page-layout {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: min(320px, 85vw);
    z-index: 1050;
    max-height: 100vh;
    padding: 1rem;
    background: var(--bg-body);
    transform: translateX(-100%);
    transition: transform var(--transition);
    box-shadow: var(--shadow-lg);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .btn-toc-mobile {
    display: inline-flex;
  }

  .section-card {
    padding: 1.5rem;
  }
}

@media (max-width: 576px) {
  .hero {
    padding: 2.5rem 1rem 2rem;
  }

  .hero-stats {
    gap: 1rem;
  }

  .slurm-tabs {
    flex-direction: column;
  }

  .slurm-tab {
    text-align: center;
  }
}