/* =============================================================================
   Variables
   ============================================================================= */

:root {
  --color-accent: #d97757;
  --color-accent-hover: #c4623d;

  --color-bg: #faf9f7;
  --color-surface: #f3f1ee;
  --color-border: #e5e2dc;
  --color-text-primary: #1a1917;
  --color-text-secondary: #6b6660;
  --color-text-muted: #9b9490;

  --color-sidebar-bg: #2d2926;
  --color-sidebar-text: #e8e5e0;
  --color-sidebar-muted: #a09893;
  --color-sidebar-active: #d97757;
  --color-sidebar-hover: rgba(255, 255, 255, 0.07);
  --color-sidebar-border: rgba(255, 255, 255, 0.08);

  --font-body: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  --sidebar-width: 280px;
  --content-max-width: 860px;

  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-full: 9999px;

  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1a1917;
    --color-surface: #242220;
    --color-border: #3a3733;
    --color-text-primary: #f0ede8;
    --color-text-secondary: #a09c97;
    --color-text-muted: #6b6660;
  }
}

[data-theme="dark"] {
  --color-bg: #1a1917;
  --color-surface: #242220;
  --color-border: #3a3733;
  --color-text-primary: #f0ede8;
  --color-text-secondary: #a09c97;
  --color-text-muted: #6b6660;
}

[data-theme="light"] {
  --color-bg: #faf9f7;
  --color-surface: #f3f1ee;
  --color-border: #e5e2dc;
  --color-text-primary: #1a1917;
  --color-text-secondary: #6b6660;
  --color-text-muted: #9b9490;
}

/* =============================================================================
   Skip Link
   ============================================================================= */

.skip-link {
  position: absolute;
  top: 0;
  left: 0;
  transform: translateY(-100%);
  background: var(--color-accent);
  color: #fff;
  padding: 0.5rem 1rem;
  font-weight: 600;
  font-size: 0.9rem;
  z-index: 9999;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  text-decoration: none;
  transition: transform var(--transition-fast);
}

.skip-link:focus {
  transform: translateY(0);
  outline: 2px solid #fff;
  outline-offset: 2px;
}

/* =============================================================================
   Reset
   ============================================================================= */

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  margin: 0 0 0.75rem;
  font-weight: 700;
  line-height: 1.3;
  color: var(--color-text-primary);
}

p {
  margin: 0 0 1rem;
}

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

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

ul {
  margin: 0;
  padding: 0 0 0 1.25rem;
}

li {
  margin-bottom: 0.35rem;
}

/* =============================================================================
   Focus Styles
   ============================================================================= */

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* =============================================================================
   Layout
   ============================================================================= */

#sideNav {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background-color: var(--color-sidebar-bg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  z-index: 100;
}

.container-fluid,
main {
  margin-left: var(--sidebar-width);
}

/* =============================================================================
   Sidebar Navigation
   ============================================================================= */

.site-nav-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem 1.25rem 1rem;
  border-bottom: 1px solid var(--color-sidebar-border);
  flex-shrink: 0;
}

.site-title {
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-sidebar-active);
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--color-sidebar-text);
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0.25rem 0.35rem;
  line-height: 1;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

.nav-toggle:hover {
  background-color: var(--color-sidebar-hover);
}

.nav-collapse {
  display: flex;
  flex-direction: column;
  flex: 1;
  overflow-y: auto;
  overflow-x: hidden;
}

.navbar-nav {
  list-style: none;
  padding: 0.75rem 0;
  margin: 0;
  flex: 1;
}

.nav-item {
  margin: 0;
}

.nav-link {
  display: block;
  padding: 0.55rem 1.25rem;
  min-height: 44px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-sidebar-muted);
  text-decoration: none;
  transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
  border-left: 3px solid transparent;
  line-height: 1.4;
}

.nav-link:hover {
  color: var(--color-sidebar-text);
  background-color: var(--color-sidebar-hover);
  text-decoration: none;
}

.nav-link.active {
  color: var(--color-sidebar-active);
  border-left-color: var(--color-sidebar-active);
  background-color: rgba(217, 119, 87, 0.08);
}

.sidebar-footer {
  padding: 1rem 1.25rem;
  border-top: 1px solid var(--color-sidebar-border);
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: flex-end;
}

#theme-toggle {
  background: none;
  border: 1px solid var(--color-sidebar-border);
  color: var(--color-sidebar-muted);
  cursor: pointer;
  padding: 0.35rem 0.6rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  line-height: 1;
  transition: color var(--transition-fast), border-color var(--transition-fast), background-color var(--transition-fast);
}

#theme-toggle:hover {
  color: var(--color-sidebar-text);
  border-color: var(--color-sidebar-muted);
  background-color: var(--color-sidebar-hover);
}

/* =============================================================================
   Main Content Sections
   ============================================================================= */

section.resume-section {
  padding: 4rem 3rem;
  max-width: var(--content-max-width);
}

.resume-section-content {
  width: 100%;
  overflow-wrap: anywhere;
  word-break: break-word;
}

/* =============================================================================
   Typography
   ============================================================================= */

h1 {
  font-size: 1.75rem;
  margin-bottom: 0.75rem;
}

h2 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.text-primary {
  color: var(--color-accent);
}

.subheading {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 1rem;
  line-height: 1.6;
}

.mb-4 {
  margin-bottom: 1.25rem !important;
}

.mb-5 {
  margin-bottom: 1.75rem !important;
}

.lead {
  font-size: 1rem;
  color: var(--color-text-primary);
}

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

/* =============================================================================
   Social Icons
   ============================================================================= */

.social-icons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.5rem;
}

.social-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.75rem;
  height: 2.75rem;
  border-radius: var(--radius-full);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  text-decoration: none;
  transition: background-color var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
  flex-shrink: 0;
}

.social-icon:hover {
  background-color: var(--color-accent);
  border-color: var(--color-accent);
  color: #fff;
  text-decoration: none;
}

.social-icon svg {
  width: 1.1rem;
  height: 1.1rem;
  fill: currentColor;
}

/* =============================================================================
   Resource Links (Topics Page)
   ============================================================================= */

.topic-resource-container {
  margin-bottom: 1.25rem;
}

.topic-resource-link {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-accent);
  transition: color var(--transition-fast);
}

.topic-resource-link:hover {
  color: var(--color-accent-hover);
}

/* =============================================================================
   Question Accordions (Questions Page)
   ============================================================================= */

details {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 0.6rem;
  background-color: var(--color-surface);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}

details:hover {
  border-color: var(--color-accent);
}

details[open] {
  border-color: var(--color-accent);
}

summary {
  cursor: pointer;
  padding: 0.8rem 1rem 0.8rem 2.5rem;
  min-height: 44px;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-primary);
  list-style: none;
  position: relative;
  user-select: none;
  transition: color var(--transition-fast);
}

summary::-webkit-details-marker {
  display: none;
}

summary::before {
  content: '';
  position: absolute;
  left: 0.9rem;
  top: 50%;
  transform: translateY(-50%) rotate(0deg);
  width: 0;
  height: 0;
  border-top: 5px solid transparent;
  border-bottom: 5px solid transparent;
  border-left: 8px solid var(--color-text-muted);
  transition: transform var(--transition-fast), border-left-color var(--transition-fast);
}

details[open] summary::before {
  transform: translateY(-50%) rotate(90deg);
  border-left-color: var(--color-accent);
}

details[open] summary {
  color: var(--color-accent);
  border-bottom: 1px solid var(--color-border);
}

details ul {
  padding: 0.75rem 1rem 0.75rem 2.5rem;
  margin: 0;
}

details ul li {
  margin-bottom: 0.4rem;
  font-size: 0.9rem;
}

details ul li a {
  color: var(--color-text-secondary);
}

details ul li a:hover {
  color: var(--color-accent);
}

/* =============================================================================
   Topic Body — Markdown-rendered content
   ============================================================================= */

.topic-body h1 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
}

.topic-body > p {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: 1.5rem;
}

.topic-body > ul {
  list-style: none;
  padding: 0;
  margin: 0;
}

.topic-body > ul > li {
  margin-bottom: 1.25rem;
}

.topic-body > ul > li > a {
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.topic-body > ul > li > a:hover {
  color: var(--color-accent-hover);
  text-decoration: underline;
}

/* Nested lists — install steps, sub-items */
.topic-body > ul > li ul {
  list-style: disc;
  padding-left: 1.25rem;
  margin-top: 0.4rem;
}

.topic-body > ul > li ul li {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin-bottom: 0.2rem;
}

/* Description text below a link (paragraph after link in list item) */
.topic-body > ul > li p {
  margin: 0.25rem 0 0;
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  line-height: 1.5;
}

/* =============================================================================
   Language switcher
   ============================================================================= */

.lang-switch {
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--color-sidebar-muted);
  text-decoration: none;
  border: 1px solid var(--color-sidebar-border);
  padding: 0.3rem 0.55rem;
  border-radius: var(--radius-sm);
  margin-right: 0.5rem;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.lang-switch:hover {
  color: var(--color-sidebar-text);
  border-color: var(--color-sidebar-muted);
  text-decoration: none;
}

/* =============================================================================
   Question hint
   ============================================================================= */

.question-hint {
  margin: 0.5rem 1rem 0.5rem 2.5rem;
  font-size: 0.88rem;
  color: var(--color-text-secondary);
  font-style: italic;
  line-height: 1.5;
}

/* =============================================================================
   Responsive — Mobile
   ============================================================================= */

@media (max-width: 767px) {
  #sideNav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    width: 100%;
    height: auto;
    flex-direction: column;
    z-index: 200;
  }

  .site-nav-header {
    padding: 0.85rem 1rem;
  }

  .nav-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
  }

  .nav-collapse {
    display: none;
    max-height: calc(100vh - 56px);
    overflow-y: auto;
    border-top: 1px solid var(--color-sidebar-border);
  }

  .nav-collapse.open {
    display: flex;
  }

  .sidebar-footer {
    padding: 0.75rem 1rem;
  }

  .container-fluid,
  main {
    margin-left: 0;
    margin-top: 56px;
  }

  section.resume-section {
    padding: 2rem 1.25rem;
  }
}

@media (min-width: 768px) {
  .nav-toggle {
    display: none;
  }

  .nav-collapse {
    display: flex !important;
  }

  section.resume-section {
    min-height: 100vh;
  }
}