/* =========================================================
   Cloud Security Architecture Lab — base stylesheet
   Plain CSS, no build step, no framework.
   ========================================================= */

/* -----------------------------------------------------------
   1. Design tokens
   ----------------------------------------------------------- */
:root,
[data-theme="dark"] {
  --color-bg: #0a0e14;
  --color-bg-elevated: #10151d;
  --color-bg-inset: #0d1117;
  --color-border: #212936;
  --color-border-strong: #2d3849;
  --color-text: #e6edf3;
  --color-text-muted: #8b98a8;
  --color-text-faint: #5b6673;
  --color-accent: #58a6ff;
  --color-accent-strong: #79c0ff;
  --color-success: #3fb950;
  --color-warning: #d29922;
  --color-danger: #f85149;
  --color-accent-bg: rgba(88, 166, 255, 0.1);
  --color-success-bg: rgba(63, 185, 80, 0.1);
  --color-warning-bg: rgba(210, 153, 34, 0.1);
  --color-danger-bg: rgba(248, 81, 73, 0.1);
  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.4);
  --color-scheme: dark;
}

[data-theme="light"] {
  --color-bg: #ffffff;
  --color-bg-elevated: #f6f8fa;
  --color-bg-inset: #eef1f4;
  --color-border: #d0d7de;
  --color-border-strong: #b6bfc9;
  --color-text: #1b1f24;
  --color-text-muted: #57606a;
  --color-text-faint: #6e7781;
  --color-accent: #0969da;
  --color-accent-strong: #0550ae;
  --color-success: #1a7f37;
  --color-warning: #9a6700;
  --color-danger: #cf222e;
  --color-accent-bg: rgba(9, 105, 218, 0.08);
  --color-success-bg: rgba(26, 127, 55, 0.08);
  --color-warning-bg: rgba(154, 103, 0, 0.08);
  --color-danger-bg: rgba(207, 34, 46, 0.08);
  --shadow-card: 0 1px 2px rgba(27, 31, 36, 0.08);
  --color-scheme: light;
}

:root {
  --font-ui: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 10px;

  --content-width: 1180px;
  --prose-width: 760px;

  --transition-fast: 120ms ease;
  --transition-base: 180ms ease;
}

/* -----------------------------------------------------------
   2. Reset & base
   ----------------------------------------------------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  color-scheme: var(--color-scheme);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-ui);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background-color var(--transition-base), color var(--transition-base);
}

img,
svg {
  display: block;
  max-width: 100%;
}

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

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

h1,
h2,
h3,
h4 {
  font-weight: 650;
  line-height: 1.25;
  letter-spacing: -0.01em;
  margin: 0 0 var(--space-4);
}

h1 { font-size: clamp(2rem, 1.6rem + 1.8vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 1.3rem + 0.9vw, 1.9rem); }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.05rem; }

p {
  margin: 0 0 var(--space-4);
  color: var(--color-text);
}

ul,
ol {
  margin: 0 0 var(--space-4);
  padding-left: 1.25em;
}

code,
pre,
kbd {
  font-family: var(--font-mono);
  font-size: 0.875em;
}

hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: var(--space-6) 0;
}

/* Visible focus states everywhere, keyboard-first */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: -100%;
  left: var(--space-4);
  z-index: 1000;
  background: var(--color-accent);
  color: #05121f;
  padding: var(--space-2) var(--space-4);
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: top var(--transition-fast);
}

.skip-link:focus {
  top: var(--space-3);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}

/* -----------------------------------------------------------
   3. Layout helpers
   ----------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--content-width);
  margin-inline: auto;
  padding-inline: var(--space-5);
}

.prose {
  max-width: var(--prose-width);
}

.prose--wide {
  max-width: 960px;
}

main {
  display: block;
}

section {
  padding-block: var(--space-7);
}

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

.section-heading h2 {
  margin: 0;
}

.section-eyebrow {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent);
  margin-bottom: var(--space-3);
}

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

/* -----------------------------------------------------------
   4. Site header / navigation
   ----------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--color-border);
}

.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding-block: var(--space-3);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 1rem;
  color: var(--color-text);
}

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

.brand__prompt {
  color: var(--color-success);
}

.brand__text-short {
  display: none;
}

@media (max-width: 480px) {
  .brand__text-full {
    display: none !important;
  }

  .brand__text-short {
    display: inline !important;
  }
}

.header-right {
  display: flex;
  align-items: center;
  gap: var(--space-5);
}

.main-nav {
  display: flex;
  align-items: center;
  gap: var(--space-6);
}

.main-nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  list-style: none;
  margin: 0;
  padding: 0;
}

.main-nav__list a {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: var(--space-2) 0;
  border-bottom: 2px solid transparent;
}

.main-nav__list a:hover {
  color: var(--color-text);
  text-decoration: none;
}

.main-nav__list a[aria-current="page"] {
  color: var(--color-text);
  border-bottom-color: var(--color-accent);
}

.header-actions {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  gap: var(--space-3);
}

.icon-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border: 1px solid var(--color-border);
  background: var(--color-bg-elevated);
  color: var(--color-text);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.icon-button:hover {
  border-color: var(--color-border-strong);
  color: var(--color-accent);
}

.icon-button svg {
  width: 1.1rem;
  height: 1.1rem;
}

.theme-toggle .icon-moon { display: none; }
[data-theme="light"] .theme-toggle .icon-sun { display: none; }
[data-theme="light"] .theme-toggle .icon-moon { display: inline-flex; }

.nav-toggle {
  display: none;
}

.nav-toggle__bar {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  position: relative;
}

.nav-toggle__bar::before,
.nav-toggle__bar::after {
  content: "";
  position: absolute;
  left: 0;
  width: 18px;
  height: 2px;
  background: currentColor;
  transition: transform var(--transition-fast);
}

.nav-toggle__bar::before { top: -6px; }
.nav-toggle__bar::after { top: 6px; }

@media (max-width: 860px) {
  .nav-toggle {
    display: inline-flex;
  }

  .main-nav {
    position: fixed;
    inset: 0 0 0 auto;
    top: 60px;
    width: min(80vw, 320px);
    height: calc(100vh - 60px);
    background: var(--color-bg-elevated);
    border-left: 1px solid var(--color-border);
    flex-direction: column;
    align-items: stretch;
    padding: var(--space-5);
    transform: translateX(100%);
    transition: transform var(--transition-base);
    overflow-y: auto;
  }

  .main-nav.is-open {
    transform: translateX(0);
  }

  .main-nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-1);
  }

  .main-nav__list a {
    display: block;
    padding: var(--space-3) var(--space-2);
    border-bottom: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
  }

  .main-nav__list a[aria-current="page"] {
    background: var(--color-accent-bg);
    border-bottom-color: var(--color-border);
  }
}

/* -----------------------------------------------------------
   5. Hero
   ----------------------------------------------------------- */
.hero {
  padding-block: var(--space-8) var(--space-7);
  border-bottom: 1px solid var(--color-border);
}

.hero__tagline {
  font-family: var(--font-mono);
  color: var(--color-success);
  font-size: 1.05rem;
  margin-bottom: var(--space-4);
}

.hero__title {
  margin-bottom: var(--space-4);
}

.hero__description {
  max-width: 640px;
  font-size: 1.05rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-6);
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

.hero--compact {
  padding-block: var(--space-7) var(--space-6);
}

/* -----------------------------------------------------------
   6. Buttons
   ----------------------------------------------------------- */
.button {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-family: var(--font-ui);
  font-size: 0.9rem;
  font-weight: 600;
  padding: var(--space-3) var(--space-5);
  border-radius: var(--radius-md);
  border: 1px solid transparent;
  cursor: pointer;
  transition: border-color var(--transition-fast), background-color var(--transition-fast), color var(--transition-fast);
}

.button:hover {
  text-decoration: none;
}

.button--primary {
  background: var(--color-accent);
  color: #05121f;
}

.button--primary:hover {
  background: var(--color-accent-strong);
  color: #05121f;
}

.button--secondary {
  background: transparent;
  border-color: var(--color-border-strong);
  color: var(--color-text);
}

.button--secondary:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.button--small {
  padding: var(--space-1) var(--space-3);
  font-size: 0.8rem;
}

/* -----------------------------------------------------------
   7. Cards
   ----------------------------------------------------------- */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-5);
}

.card {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-5);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.card:hover {
  border-color: var(--color-border-strong);
  transform: translateY(-2px);
}

.card__meta {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-faint);
}

.card__title {
  font-size: 1.05rem;
  margin: 0;
}

.card__description {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin: 0;
  flex-grow: 1;
}

.card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.card--featured {
  border-color: var(--color-accent);
  background: linear-gradient(180deg, var(--color-accent-bg), var(--color-bg-elevated) 60%);
}

/* Category cards on homepage */
.category-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  padding: var(--space-5);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  color: var(--color-text);
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.category-card:hover {
  border-color: var(--color-accent);
  color: var(--color-text);
  text-decoration: none;
}

.category-card__count {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-faint);
}

/* -----------------------------------------------------------
   8. Tags & badges
   ----------------------------------------------------------- */
.tag {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  background: var(--color-bg-inset);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-size: 0.72rem;
  font-weight: 600;
  padding: 0.15em 0.6em;
  border-radius: 999px;
  border: 1px solid transparent;
}

.badge--success {
  background: var(--color-success-bg);
  color: var(--color-success);
  border-color: color-mix(in srgb, var(--color-success) 40%, transparent);
}

.badge--warning {
  background: var(--color-warning-bg);
  color: var(--color-warning);
  border-color: color-mix(in srgb, var(--color-warning) 40%, transparent);
}

.badge--neutral {
  background: var(--color-bg-inset);
  color: var(--color-text-muted);
  border-color: var(--color-border);
}

/* -----------------------------------------------------------
   9. Filter / search controls (blog page)
   ----------------------------------------------------------- */
.filter-bar {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  padding: var(--space-5);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-6);
}

.search-field {
  position: relative;
  display: flex;
  align-items: center;
}

.search-field svg {
  position: absolute;
  left: var(--space-3);
  width: 1rem;
  height: 1rem;
  color: var(--color-text-faint);
}

.search-field input {
  width: 100%;
  padding: var(--space-3) var(--space-3) var(--space-3) var(--space-7);
  background: var(--color-bg-inset);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text);
  font-family: var(--font-ui);
  font-size: 0.9rem;
}

.search-field input:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 1px;
}

.filter-chips {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
}

.filter-chip {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  padding: var(--space-2) var(--space-3);
  border-radius: 999px;
  border: 1px solid var(--color-border);
  background: var(--color-bg-inset);
  color: var(--color-text-muted);
  cursor: pointer;
  transition: border-color var(--transition-fast), color var(--transition-fast), background-color var(--transition-fast);
}

.filter-chip:hover {
  border-color: var(--color-border-strong);
  color: var(--color-text);
}

.filter-chip[aria-pressed="true"] {
  background: var(--color-accent-bg);
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.filter-results-count {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.empty-state {
  padding: var(--space-7) var(--space-5);
  text-align: center;
  color: var(--color-text-muted);
  border: 1px dashed var(--color-border);
  border-radius: var(--radius-lg);
}

/* -----------------------------------------------------------
   10. Code blocks
   ----------------------------------------------------------- */
.code-block {
  position: relative;
  background: var(--color-bg-inset);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin: var(--space-5) 0;
  overflow: hidden;
}

.code-block__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-2) var(--space-4);
  border-bottom: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-faint);
}

.code-block pre {
  margin: 0;
  padding: var(--space-4);
  overflow-x: auto;
  line-height: 1.55;
}

.code-block code {
  color: var(--color-text);
  background: none;
}

.copy-button {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  color: var(--color-text-muted);
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: border-color var(--transition-fast), color var(--transition-fast);
}

.copy-button:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

.copy-button[data-copied="true"] {
  border-color: var(--color-success);
  color: var(--color-success);
}

/* -----------------------------------------------------------
   11. Architecture diagram
   ----------------------------------------------------------- */
.diagram {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-6) var(--space-5);
  background: var(--color-bg-inset);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  margin: var(--space-5) 0;
}

.diagram__node {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: var(--space-1);
  min-width: 128px;
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border-strong);
  border-radius: var(--radius-md);
  font-size: 0.82rem;
  font-weight: 600;
}

.diagram__node--gate {
  border-color: var(--color-warning);
  color: var(--color-warning);
}

.diagram__node--gate .diagram__node-sub {
  color: var(--color-warning);
}

.diagram__node-sub {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 400;
  color: var(--color-text-faint);
}

.diagram__arrow {
  color: var(--color-text-faint);
  font-family: var(--font-mono);
  flex-shrink: 0;
}

@media (max-width: 700px) {
  .diagram {
    flex-direction: column;
    align-items: stretch;
  }

  .diagram__arrow {
    align-self: center;
    transform: rotate(90deg);
  }

  .diagram__node {
    width: 100%;
  }
}

/* -----------------------------------------------------------
   12. Security controls list
   ----------------------------------------------------------- */
.control-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  margin: var(--space-5) 0;
  padding: 0;
  list-style: none;
}

.control-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-success);
  border-radius: var(--radius-md);
}

.control-item--planned {
  border-left-color: var(--color-warning);
}

.control-item__body h4 {
  margin: 0 0 var(--space-1);
  font-size: 0.95rem;
}

.control-item__body p {
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

/* -----------------------------------------------------------
   13. Tables
   ----------------------------------------------------------- */
.table-wrapper {
  overflow-x: auto;
  margin: var(--space-5) 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

th,
td {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--color-border);
}

thead th {
  background: var(--color-bg-inset);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-muted);
}

tbody tr:last-child td {
  border-bottom: none;
}

tbody tr:hover {
  background: var(--color-bg-inset);
}

/* -----------------------------------------------------------
   14. Alerts
   ----------------------------------------------------------- */
.alert {
  display: flex;
  gap: var(--space-3);
  padding: var(--space-4) var(--space-5);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-accent);
  border-radius: var(--radius-md);
  background: var(--color-bg-elevated);
  margin: var(--space-5) 0;
}

.alert p {
  margin: 0;
  font-size: 0.9rem;
}

.alert p:first-child {
  font-weight: 600;
  margin-bottom: var(--space-1);
}

.alert--info { border-left-color: var(--color-accent); }
.alert--success { border-left-color: var(--color-success); }
.alert--warning { border-left-color: var(--color-warning); }
.alert--danger { border-left-color: var(--color-danger); }

/* -----------------------------------------------------------
   15. Philosophy / step blocks (about page)
   ----------------------------------------------------------- */
.step-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-5);
  margin: var(--space-6) 0;
}

.step-card {
  padding: var(--space-5);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
}

.step-card__index {
  font-family: var(--font-mono);
  color: var(--color-accent);
  font-size: 0.8rem;
  margin-bottom: var(--space-2);
}

.step-card h3 {
  margin-bottom: var(--space-2);
}

.step-card p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin: 0;
}

/* -----------------------------------------------------------
   16. Footer
   ----------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding-block: var(--space-6);
  margin-top: var(--space-7);
}

.site-footer__inner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
}

.site-footer p {
  margin: 0;
  font-size: 0.85rem;
  color: var(--color-text-faint);
}

.site-footer__links {
  display: flex;
  gap: var(--space-4);
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-footer__links a {
  color: var(--color-text-muted);
  font-size: 0.85rem;
}

/* -----------------------------------------------------------
   17. Utility
   ----------------------------------------------------------- */
.stack {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

.mt-0 { margin-top: 0; }
.mb-0 { margin-bottom: 0; }

.tag-group--spaced {
  margin-bottom: var(--space-5);
}

@media (max-width: 600px) {
  section {
    padding-block: var(--space-6);
  }

  .hero {
    padding-block: var(--space-6) var(--space-5);
  }
}

/* -----------------------------------------------------------
   18. Learn dropdown navigation
   ----------------------------------------------------------- */
.nav-dropdown {
  position: relative;
  list-style: none;
}

.nav-dropdown summary {
  display: flex;
  align-items: center;
  gap: 0.3em;
  list-style: none;
  cursor: pointer;
  color: var(--color-text-muted);
  font-size: 0.9rem;
  font-weight: 500;
  padding: var(--space-2) 0;
  border-bottom: 2px solid transparent;
  user-select: none;
}

.nav-dropdown summary::-webkit-details-marker,
.nav-dropdown summary::marker {
  display: none;
  content: "";
}

.nav-dropdown summary:hover {
  color: var(--color-text);
}

.nav-dropdown[open] summary,
.nav-dropdown.has-active summary {
  color: var(--color-text);
  border-bottom-color: var(--color-accent);
}

.nav-dropdown__chevron {
  width: 0.7rem;
  height: 0.7rem;
  transition: transform var(--transition-fast);
}

.nav-dropdown[open] .nav-dropdown__chevron {
  transform: rotate(180deg);
}

.nav-dropdown__panel {
  display: grid;
  gap: 2px;
  position: absolute;
  top: calc(100% + var(--space-3));
  left: 50%;
  transform: translateX(-50%);
  width: max-content;
  min-width: 300px;
  padding: var(--space-2);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.45);
  z-index: 200;
}

.nav-dropdown__panel a {
  display: flex;
  align-items: baseline;
  gap: var(--space-3);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  color: var(--color-text);
  font-size: 0.85rem;
}

.nav-dropdown__panel a:hover {
  background: var(--color-bg-inset);
  color: var(--color-accent);
  text-decoration: none;
}

.nav-dropdown__panel a[aria-current="page"] {
  background: var(--color-accent-bg);
  color: var(--color-accent);
}

.nav-dropdown__index {
  flex-shrink: 0;
  width: 1.4em;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--color-text-faint);
}

@media (max-width: 860px) {
  .nav-dropdown__panel {
    position: static;
    transform: none;
    width: auto;
    min-width: 0;
    box-shadow: none;
    border: none;
    background: transparent;
    padding: 0 0 var(--space-2) var(--space-3);
  }

  .nav-dropdown summary {
    padding: var(--space-3) var(--space-2);
    border-bottom: 1px solid var(--color-border);
  }
}

/* -----------------------------------------------------------
   19. Roadmap
   ----------------------------------------------------------- */
.roadmap {
  list-style: none;
  margin: var(--space-6) 0 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.roadmap-item {
  position: relative;
}

.roadmap-item:not(:last-child)::after {
  content: "";
  position: absolute;
  left: calc(var(--space-5) + 1.375rem - 1px);
  top: 100%;
  width: 2px;
  height: var(--space-3);
  background: var(--color-border-strong);
}

.roadmap-item__link {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  padding: var(--space-4) var(--space-5);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  color: var(--color-text);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.roadmap-item__link:hover {
  border-color: var(--color-accent);
  transform: translateX(4px);
  color: var(--color-text);
  text-decoration: none;
}

.roadmap-item__index {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: 50%;
  background: var(--color-bg-inset);
  border: 1px solid var(--color-border-strong);
  font-family: var(--font-mono);
  font-weight: 700;
  color: var(--color-accent);
}

.roadmap-item__body {
  flex-grow: 1;
  display: flex;
  flex-direction: column;
  gap: 0.2em;
  min-width: 0;
}

.roadmap-item__title {
  font-weight: 600;
  font-size: 1rem;
}

.roadmap-item__desc {
  font-size: 0.85rem;
  color: var(--color-text-muted);
}

.roadmap-item__arrow {
  flex-shrink: 0;
  color: var(--color-text-faint);
  font-family: var(--font-mono);
}

@media (max-width: 600px) {
  .roadmap-item__link {
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
  }

  .roadmap-item__arrow {
    display: none;
  }
}

/* -----------------------------------------------------------
   20. Cloud provider cards
   ----------------------------------------------------------- */
.provider-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-5);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-top: 3px solid var(--provider-color, var(--color-accent));
  border-radius: var(--radius-lg);
  color: var(--color-text);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.provider-card:hover {
  border-color: var(--color-border-strong);
  border-top-color: var(--provider-color, var(--color-accent));
  transform: translateY(-2px);
  color: var(--color-text);
  text-decoration: none;
}

.provider-card[data-provider="aws"] { --provider-color: #ff9900; }
.provider-card[data-provider="azure"] { --provider-color: #0078d4; }
.provider-card[data-provider="gcp"] { --provider-color: #34a853; }

.provider-card__badge {
  align-self: flex-start;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  color: var(--provider-color, var(--color-accent));
  border: 1px solid currentColor;
  padding: 0.15em 0.6em;
  border-radius: 999px;
}

.provider-card__title {
  margin: 0;
  font-size: 1.1rem;
}

.provider-card__desc {
  margin: 0;
  flex-grow: 1;
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

.provider-card__cta {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--provider-color, var(--color-accent));
}

/* -----------------------------------------------------------
   21. Hands-on lab cards
   ----------------------------------------------------------- */
.lab-card {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
  padding: var(--space-5);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  color: var(--color-text);
  transition: border-color var(--transition-fast), transform var(--transition-fast);
}

.lab-card:hover {
  border-color: var(--color-accent);
  transform: translateY(-2px);
  color: var(--color-text);
  text-decoration: none;
}

.lab-card__meta {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.lab-card__title {
  margin: 0;
  font-size: 1.05rem;
}

.lab-card__desc {
  margin: 0;
  flex-grow: 1;
  color: var(--color-text-muted);
  font-size: 0.88rem;
}

.lab-card__cta {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--color-accent);
}

.badge--danger {
  background: var(--color-danger-bg);
  color: var(--color-danger);
  border-color: color-mix(in srgb, var(--color-danger) 40%, transparent);
}

/* -----------------------------------------------------------
   22. Terminal-style code block
   ----------------------------------------------------------- */
.terminal .code-block__header {
  justify-content: space-between;
}

.terminal__label {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--color-text-faint);
}

.terminal__dots {
  display: inline-flex;
  gap: 6px;
}

.terminal__dots span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

.terminal__dots span:nth-child(1) { background: #f85149; }
.terminal__dots span:nth-child(2) { background: #d29922; }
.terminal__dots span:nth-child(3) { background: #3fb950; }

.terminal .prompt {
  color: var(--color-success);
  user-select: none;
}

.terminal .comment {
  color: var(--color-text-faint);
}

/* -----------------------------------------------------------
   23. Hands-on lab flow steps
   ----------------------------------------------------------- */
.lab-flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--space-2) 0;
  list-style: none;
  margin: var(--space-5) 0;
  padding: 0;
}

.lab-flow__step {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.lab-flow__step a {
  display: inline-flex;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--color-border);
  border-radius: 999px;
  background: var(--color-bg-inset);
  color: var(--color-text-muted);
}

.lab-flow__step a:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

.lab-flow__arrow {
  color: var(--color-text-faint);
  font-family: var(--font-mono);
}

/* -----------------------------------------------------------
   24. Checklist
   ----------------------------------------------------------- */
.checklist {
  list-style: none;
  margin: var(--space-5) 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.checklist-item label {
  display: flex;
  align-items: flex-start;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  background: var(--color-bg-elevated);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 0.92rem;
  transition: border-color var(--transition-fast), background-color var(--transition-fast);
}

.checklist-item label:hover {
  border-color: var(--color-border-strong);
}

.checklist-item input[type="checkbox"] {
  flex-shrink: 0;
  width: 1.05rem;
  height: 1.05rem;
  margin-top: 0.2em;
  accent-color: var(--color-success);
}

.checklist-item.is-checked label {
  background: var(--color-success-bg);
  border-color: color-mix(in srgb, var(--color-success) 40%, var(--color-border));
}

.checklist-item.is-checked .checklist-item__text {
  color: var(--color-text-muted);
  text-decoration: line-through;
}

/* -----------------------------------------------------------
   25. Risk variant for control items
   ----------------------------------------------------------- */
.control-item--risk {
  border-left-color: var(--color-danger);
}

/* -----------------------------------------------------------
   26. Lab panel (collapsible hands-on lab write-up)
   ----------------------------------------------------------- */
.lab-panel {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-bg-elevated);
  margin: var(--space-6) 0;
  overflow: hidden;
}

.lab-panel__summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-5);
  cursor: pointer;
  list-style: none;
}

.lab-panel__summary::-webkit-details-marker,
.lab-panel__summary::marker {
  display: none;
  content: "";
}

.lab-panel__summary:hover .lab-panel__chevron {
  color: var(--color-accent);
}

.lab-panel__summary h2 {
  margin: 0;
  font-size: 1.15rem;
  display: inline-flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.lab-panel__chevron {
  flex-shrink: 0;
  width: 1.1rem;
  height: 1.1rem;
  color: var(--color-text-faint);
  transition: transform var(--transition-fast);
}

.lab-panel[open] .lab-panel__chevron {
  transform: rotate(180deg);
}

.lab-panel__body {
  padding: 0 var(--space-5) var(--space-5);
  border-top: 1px solid var(--color-border);
  padding-top: var(--space-5);
}