/* ASP.NET Core Mastery - Educational Stylesheet */
/* A clean, readable design optimized for long-form technical learning */

/* ==================== CSS Variables ==================== */
:root {
  /* Colors - Warm, easy-on-the-eyes palette */
  --color-bg: #fefdfb;
  --color-bg-alt: #f8f6f3;
  --color-bg-code: #1e1e1e;
  --color-text: #2d2a26;
  --color-text-muted: #6b6560;
  --color-text-light: #918a82;
  --color-heading: #1a1816;
  --color-link: #2563eb;
  --color-link-hover: #1d4ed8;
  --color-accent: #7c3aed;
  --color-accent-light: #ede9fe;
  --color-success: #059669;
  --color-success-light: #d1fae5;
  --color-warning: #d97706;
  --color-warning-light: #fef3c7;
  --color-info: #0891b2;
  --color-info-light: #cffafe;
  --color-border: #e5e2de;
  --color-border-dark: #d1cdc7;

  /* Typography */
  --font-body: 'Source Serif 4', 'Georgia', serif;
  --font-heading: 'DM Sans', 'Segoe UI', sans-serif;
  --font-code: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;

  /* Layout */
  --content-width: 50rem;
  --sidebar-width: 16rem;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

/* ==================== Base Styles ==================== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  font-size: 1.125rem;
  line-height: 1.75;
  color: var(--color-text);
  background-color: var(--color-bg);
}

/* ==================== Typography ==================== */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--color-heading);
  line-height: 1.3;
  margin-top: var(--space-2xl);
  margin-bottom: var(--space-md);
}

h1 {
  font-size: 2.5rem;
  font-weight: 700;
  margin-top: 0;
  padding-bottom: var(--space-md);
  border-bottom: 3px solid var(--color-accent);
}

h2 {
  font-size: 1.875rem;
  margin-top: var(--space-3xl);
  padding-bottom: var(--space-sm);
  border-bottom: 1px solid var(--color-border);
}

h3 {
  font-size: 1.5rem;
  color: var(--color-accent);
}

h4 {
  font-size: 1.25rem;
}

p {
  margin: 0 0 var(--space-lg) 0;
}

a {
  color: var(--color-link);
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: all var(--transition-fast);
}

a:hover {
  color: var(--color-link-hover);
  border-bottom-color: var(--color-link-hover);
}

strong {
  font-weight: 600;
  color: var(--color-heading);
}

em {
  font-style: italic;
}

/* ==================== Layout ==================== */
.page-wrapper {
  display: flex;
  min-height: 100vh;
}

.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-bg-alt);
  border-right: 1px solid var(--color-border);
  padding: var(--space-xl);
  overflow-y: auto;
  z-index: 100;
}

.sidebar-logo {
  font-family: var(--font-heading);
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--color-heading);
  text-decoration: none;
  display: block;
  margin-bottom: var(--space-xl);
  padding-bottom: var(--space-md);
  border-bottom: 2px solid var(--color-accent);
}

.sidebar-logo:hover {
  color: var(--color-accent);
  border-bottom-color: var(--color-accent);
}

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

.sidebar-nav li {
  margin-bottom: var(--space-xs);
}

.sidebar-nav a {
  display: block;
  padding: var(--space-sm) var(--space-md);
  color: var(--color-text-muted);
  border-radius: 6px;
  font-family: var(--font-heading);
  font-size: 0.9rem;
  border-bottom: none;
  transition: all var(--transition-fast);
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
  background: var(--color-bg);
  color: var(--color-heading);
}

.sidebar-nav a.active {
  color: var(--color-accent);
  font-weight: 600;
}

.sidebar-section {
  margin-top: var(--space-lg);
  margin-bottom: var(--space-sm);
  font-family: var(--font-heading);
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-text-light);
}

.main-content {
  flex: 1;
  margin-left: var(--sidebar-width);
  padding: var(--space-3xl);
  max-width: calc(var(--content-width) + var(--space-3xl) * 2);
}

/* No sidebar layout (for index page) */
.main-content.full-width {
  margin-left: 0;
  max-width: none;
}

.content-container {
  max-width: var(--content-width);
  margin: 0 auto;
}

/* ==================== Navigation ==================== */
.breadcrumb {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xl);
}

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

.breadcrumb a:hover {
  color: var(--color-link);
}

.breadcrumb span {
  margin: 0 var(--space-sm);
}

.page-nav {
  display: flex;
  justify-content: space-between;
  margin-top: var(--space-3xl);
  padding-top: var(--space-xl);
  border-top: 1px solid var(--color-border);
}

.page-nav a {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-family: var(--font-heading);
  font-weight: 500;
  padding: var(--space-md) var(--space-lg);
  background: var(--color-bg-alt);
  border-radius: 8px;
  border-bottom: none;
  transition: all var(--transition-fast);
}

.page-nav a:hover {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

.page-nav .prev::before {
  content: '←';
}

.page-nav .next::after {
  content: '→';
}

/* ==================== Code Blocks ==================== */
code {
  font-family: var(--font-code);
  font-size: 0.9em;
  background: var(--color-bg-alt);
  padding: 0.15em 0.4em;
  border-radius: 4px;
  border: 1px solid var(--color-border);
}

pre {
  background: var(--color-bg-code);
  color: #d4d4d4;
  padding: var(--space-lg);
  border-radius: 8px;
  overflow-x: auto;
  margin: var(--space-lg) 0;
  border: 1px solid #333;
}

pre code {
  background: none;
  padding: 0;
  border: none;
  font-size: 0.875rem;
  line-height: 1.6;
}

/* Syntax highlighting (VS Code Dark+ inspired) */
.code-keyword {
  color: #569cd6;
}

.code-string {
  color: #ce9178;
}

.code-comment {
  color: #6a9955;
  font-style: italic;
}

.code-number {
  color: #b5cea8;
}

.code-class {
  color: #4ec9b0;
}

.code-method {
  color: #dcdcaa;
}

.code-variable {
  color: #9cdcfe;
}

.code-type {
  color: #4ec9b0;
}

.code-attribute {
  color: #9cdcfe;
}

.code-operator {
  color: #d4d4d4;
}

/* Code block header */
.code-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: #2d2d2d;
  padding: var(--space-sm) var(--space-lg);
  border-radius: 8px 8px 0 0;
  border: 1px solid #333;
  border-bottom: none;
  margin-top: var(--space-lg);
}

.code-header+pre {
  margin-top: 0;
  border-radius: 0 0 8px 8px;
}

.code-filename {
  font-family: var(--font-code);
  font-size: 0.8rem;
  color: #888;
}

.code-language {
  font-family: var(--font-heading);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #888;
  background: #404040;
  padding: 0.2em 0.6em;
  border-radius: 4px;
}

/* ==================== Callout Boxes ==================== */
.callout {
  padding: var(--space-lg);
  border-radius: 8px;
  margin: var(--space-xl) 0;
  border-left: 4px solid;
}

.callout-title {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

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

.callout-info {
  background: var(--color-info-light);
  border-color: var(--color-info);
}

.callout-info .callout-title {
  color: var(--color-info);
}

.callout-tip {
  background: var(--color-success-light);
  border-color: var(--color-success);
}

.callout-tip .callout-title {
  color: var(--color-success);
}

.callout-warning {
  background: var(--color-warning-light);
  border-color: var(--color-warning);
}

.callout-warning .callout-title {
  color: var(--color-warning);
}

.callout-concept {
  background: var(--color-accent-light);
  border-color: var(--color-accent);
}

.callout-concept .callout-title {
  color: var(--color-accent);
}

/* ==================== Tables ==================== */
table {
  width: 100%;
  border-collapse: collapse;
  margin: var(--space-lg) 0;
  font-size: 0.95rem;
}

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

th {
  font-family: var(--font-heading);
  font-weight: 600;
  background: var(--color-bg-alt);
  color: var(--color-heading);
}

tr:hover td {
  background: var(--color-bg-alt);
}

/* ==================== Lists ==================== */
ul,
ol {
  margin: 0 0 var(--space-lg) 0;
  padding-left: var(--space-xl);
}

li {
  margin-bottom: var(--space-sm);
}

li::marker {
  color: var(--color-accent);
}

/* Definition lists for concept explanations */
dl {
  margin: var(--space-lg) 0;
}

dt {
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--color-heading);
  margin-top: var(--space-md);
}

dd {
  margin-left: var(--space-xl);
  margin-bottom: var(--space-md);
  color: var(--color-text-muted);
}

/* ==================== Special Elements ==================== */

/* Learning objectives box */
.learning-objectives {
  background: linear-gradient(135deg, var(--color-accent-light) 0%, #f5f3ff 100%);
  border: 1px solid var(--color-accent);
  border-radius: 12px;
  padding: var(--space-xl);
  margin: var(--space-xl) 0;
}

.learning-objectives h3 {
  margin-top: 0;
  color: var(--color-accent);
  font-size: 1.1rem;
}

.learning-objectives ul {
  margin-bottom: 0;
}

/* Key term highlight */
.term {
  font-weight: 600;
  color: var(--color-accent);
  border-bottom: 2px dotted var(--color-accent);
  cursor: help;
}

/* Analogy/metaphor block */
.analogy {
  background: var(--color-bg-alt);
  border-radius: 8px;
  padding: var(--space-lg);
  margin: var(--space-lg) 0;
  font-style: italic;
  position: relative;
}

.analogy::before {
  content: '💡';
  position: absolute;
  top: -12px;
  left: var(--space-lg);
  background: var(--color-bg);
  padding: 0 var(--space-sm);
}

/* Progress indicator */
.progress-indicator {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  font-family: var(--font-heading);
  font-size: 0.875rem;
  color: var(--color-text-muted);
  margin-bottom: var(--space-xl);
}

.progress-bar {
  flex: 1;
  height: 6px;
  background: var(--color-border);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-accent), var(--color-success));
  border-radius: 3px;
  transition: width var(--transition-normal);
}

/* Section divider */
.section-divider {
  text-align: center;
  margin: var(--space-3xl) 0;
  color: var(--color-text-light);
}

.section-divider::before {
  content: '• • •';
  letter-spacing: 0.5em;
}

/* ==================== Index Page Specific ==================== */
.hero {
  text-align: center;
  padding: var(--space-3xl) 0;
  margin-bottom: var(--space-2xl);
  background: linear-gradient(180deg, var(--color-accent-light) 0%, var(--color-bg) 100%);
  border-radius: 16px;
}

.hero h1 {
  font-size: 3rem;
  border: none;
  margin-bottom: var(--space-md);
}

.hero .subtitle {
  font-size: 1.25rem;
  color: var(--color-text-muted);
  max-width: 40rem;
  margin: 0 auto;
}

.roadmap-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-xl);
  margin: var(--space-2xl) 0;
}

.roadmap-card {
  background: var(--color-bg-alt);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: var(--space-xl);
  transition: all var(--transition-fast);
}

.roadmap-card:hover {
  border-color: var(--color-accent);
  box-shadow: 0 4px 20px rgba(124, 58, 237, 0.1);
  transform: translateY(-2px);
}

.roadmap-card h3 {
  margin-top: 0;
  font-size: 1.25rem;
}

.roadmap-card .part-number {
  font-family: var(--font-code);
  font-size: 0.75rem;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: 0.1em;
}

.roadmap-card ul {
  font-size: 0.95rem;
  color: var(--color-text-muted);
}

.roadmap-card a {
  display: inline-block;
  margin-top: var(--space-md);
  font-family: var(--font-heading);
  font-weight: 500;
}

/* ==================== Print Styles ==================== */
@media print {

  .sidebar,
  .page-nav,
  .breadcrumb {
    display: none;
  }

  .main-content {
    margin-left: 0;
    padding: 0;
  }

  pre {
    white-space: pre-wrap;
    word-wrap: break-word;
  }

  a {
    color: inherit;
    text-decoration: underline;
  }
}

/* ==================== Responsive ==================== */
@media (max-width: 900px) {
  .sidebar {
    position: static;
    width: 100%;
    height: auto;
    border-right: none;
    border-bottom: 1px solid var(--color-border);
  }

  .main-content {
    margin-left: 0;
    padding: var(--space-xl);
  }

  .page-wrapper {
    flex-direction: column;
  }

  h1 {
    font-size: 2rem;
  }

  .hero h1 {
    font-size: 2.25rem;
  }
}

/* ==================== Footer ==================== */
.page-footer {
  margin-top: var(--space-3xl);
  padding: var(--space-xl) 0;
  border-top: 1px solid var(--color-border);
  text-align: center;
  font-family: var(--font-heading);
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.page-footer a {
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition-fast);
}

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

/* ==================== Top Navigation ==================== */
.top-nav {
  position: fixed;
  top: 0;
  right: 0;
  padding: var(--space-lg) var(--space-xl);
  z-index: 1000;
}

.top-nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-family: var(--font-heading);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.top-nav a:hover {
  color: var(--color-accent);
}

/* ==================== About Author ==================== */
.about-author {
  margin: var(--space-3xl) 0;
  padding: var(--space-xl);
  background: linear-gradient(135deg, var(--color-accent-light) 0%, var(--color-bg-alt) 100%);
  border-radius: 12px;
  border-left: 4px solid var(--color-accent);
}

.about-author h3 {
  margin-top: 0;
  color: var(--color-accent);
  font-size: 1.5rem;
}

.author-content {
  display: flex;
  gap: var(--space-xl);
  align-items: center;
}

.author-avatar {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  background: var(--color-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 2.5rem;
  color: white;
  flex-shrink: 0;
}

.author-info {
  flex: 1;
}

.author-info p {
  margin: 0 0 var(--space-md) 0;
  line-height: 1.6;
}

.author-links {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.author-links a {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: var(--space-sm) var(--space-md);
  background: white;
  color: var(--color-accent);
  text-decoration: none;
  border-radius: 6px;
  font-family: var(--font-heading);
  font-weight: 500;
  font-size: 0.9rem;
  transition: all var(--transition-fast);
  border: 2px solid transparent;
}

.author-links a:hover {
  background: var(--color-accent);
  color: white;
  border-color: var(--color-accent);
  transform: translateY(-2px);
}

@media (max-width: 768px) {
  .author-content {
    flex-direction: column;
    text-align: center;
  }

  .author-links {
    justify-content: center;
  }
}

/* ==================== Font Loading ==================== */
/* Using Google Fonts - loaded in HTML head */