/* ==========================================
   Global Styles & CSS Variables
   ========================================== */

:root {
  /* Brand Colors */
  --color-primary: #25c2a0;
  --color-primary-dark: #1fa588;
  --color-primary-light: #32d8b4;
  --color-accent-red: #ee0000;
  --color-accent-green: #008800;
  --color-accent-orange: #aa6600;

  /* Light Theme */
  --color-bg: #ffffff;
  --color-bg-secondary: #f8f9fa;
  --color-bg-tertiary: #e9ecef;
  --color-text: #1a1a1a;
  --color-text-secondary: #4a5568;
  --color-text-tertiary: #718096;
  --color-border: #e2e8f0;
  --color-shadow: rgba(0, 0, 0, 0.1);

  /* Typography */
  --font-family-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-family-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;

  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 6rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-full: 9999px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-base: 250ms ease;
  --transition-slow: 350ms ease;

  /* Container */
  --container-max-width: 1200px;
}

[data-theme="dark"] {
  --color-bg: #0f1419;
  --color-bg-secondary: #1a1f2e;
  --color-bg-tertiary: #252b3b;
  --color-text: #f0f0f0;
  --color-text-secondary: #c5d0de;
  --color-text-tertiary: #9ca3af;
  --color-border: #2d3748;
  --color-shadow: rgba(0, 0, 0, 0.3);
}

/* ==========================================
   Reset & Base Styles
   ========================================== */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-bg);
  transition: background-color var(--transition-base), color var(--transition-base);
}

.container {
  width: 100%;
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

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

h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 700;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

h1 {
  font-size: 2.25rem;
}

h2 {
  font-size: 2rem;
}

h3 {
  font-size: 1.5rem;
}

h4 {
  font-size: 1.25rem;
}

h5 {
  font-size: 1.125rem;
}

h6 {
  font-size: 1rem;
}

p {
  margin-bottom: var(--spacing-lg);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

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

a:hover {
  color: var(--color-primary-dark);
}

code {
  font-family: var(--font-family-mono);
  font-size: 0.875em;
  padding: 0.125rem 0.375rem;
  background-color: var(--color-bg-tertiary);
  border-radius: var(--radius-sm);
}

pre {
  background-color: var(--color-bg-tertiary);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--spacing-md);
}

pre code {
  padding: 0;
  background-color: transparent;
}

/* ==========================================
   Header
   ========================================== */

.site-header {
  background-color: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
  background-color: rgba(255, 255, 255, 0.9);
}

[data-theme="dark"] .site-header {
  background-color: rgba(15, 20, 25, 0.9);
}

.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: var(--color-primary);
  z-index: 1001;
  transition: width 0.1s ease-out;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--spacing-md);
}

.header-left {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-text);
}

.logo img {
  width: 50px;
  height: 50px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: 3px solid var(--color-primary);
  transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.logo:hover img {
  transform: scale(1.05);
  box-shadow: 0 4px 12px var(--color-shadow);
}

.main-nav ul {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
}

.main-nav a {
  color: var(--color-text-secondary);
  font-weight: 500;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
}

.main-nav a:hover,
.main-nav a.active {
  color: var(--color-primary);
  background-color: var(--color-bg-secondary);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
  color: var(--color-text);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

.theme-toggle:hover {
  background-color: var(--color-bg-secondary);
}

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

[data-theme="dark"] .sun-icon {
  display: none;
}

.github-link {
  color: var(--color-text);
  display: flex;
  align-items: center;
  padding: var(--spacing-xs);
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

.github-link:hover {
  background-color: var(--color-bg-secondary);
}

.sidebar-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--spacing-xs);
  color: var(--color-text);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-sm);
  transition: background-color var(--transition-fast);
}

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

/* ==========================================
   Footer
   ========================================== */

.site-footer {
  background-color: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-2xl) 0 var(--spacing-lg);
  margin-top: var(--spacing-3xl);
}

.footer-grid {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  max-width: 600px;
  margin: 0 auto var(--spacing-xl);
}

.footer-section:first-child {
  text-align: left;
}

.footer-section:last-child {
  text-align: right;
}

@media (max-width: 768px) {
  .footer-grid {
    flex-direction: column;
    gap: var(--spacing-xl);
    align-items: stretch;
    width: fit-content;
    margin-left: auto;
    margin-right: auto;
  }

  .footer-section:first-child,
  .footer-section:last-child {
    text-align: left;
    width: auto;
  }
}

.footer-section h3 {
  font-size: 1rem;
  margin-bottom: var(--spacing-md);
  color: var(--color-text);
}

.footer-section ul {
  list-style: none;
}

.footer-section li {
  margin-bottom: var(--spacing-xs);
}

.footer-section a {
  color: var(--color-text-secondary);
  transition: color var(--transition-fast);
}

.footer-section a:hover {
  color: var(--color-primary);
}

.footer-bottom {
  text-align: center;
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  color: var(--color-text-tertiary);
}

/* ==========================================
   Buttons
   ========================================== */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: 1rem;
  text-decoration: none;
  transition: all var(--transition-base);
  border: none;
  cursor: pointer;
  font-family: inherit;
}

.btn-primary {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
  color: white;
  box-shadow: 0 4px 14px rgba(37, 194, 160, 0.3);
}

.btn-primary:hover {
  transform: translateY(-3px);
  background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
  box-shadow: 0 8px 25px rgba(37, 194, 160, 0.45);
  color: #ffffff;
}

.btn-secondary {
  background-color: var(--color-bg-tertiary);
  color: var(--color-text);
}

.btn-secondary:hover {
  background-color: var(--color-border);
}

.btn-large {
  padding: var(--spacing-sm) var(--spacing-xl);
  font-size: 1.125rem;
}

/* ==========================================
   Responsive Design
   ========================================== */

@media (max-width: 768px) {
  .main-nav ul {
    gap: var(--spacing-sm);
  }

  .main-nav a {
    font-size: 0.875rem;
    padding: var(--spacing-xs);
  }

  .logo-text {
    display: none;
  }

  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.75rem;
  }

  h3 {
    font-size: 1.25rem;
  }
}

/* ==========================================
/* ==========================================
   Syntax Highlighting (Prism.js)
   ========================================== */

:root {
  --syntax-bg: #0f1419;
  --syntax-text: #f8f8f2;
  --syntax-comment: #5c6773;
  --syntax-keyword: #ff7733;
  --syntax-function: #36a3d9;
  --syntax-string: #25c2a0;
  /* Using brand primary */
  --syntax-number: #ffb454;
  --syntax-class: #36a3d9;
  --syntax-punctuation: #f8f8f2;
}

[data-theme="light"] {
  --syntax-bg: #f8f9fa;
  --syntax-text: #24292e;
  --syntax-comment: #6a737d;
  --syntax-keyword: #d73a49;
  --syntax-function: #6f42c1;
  --syntax-string: #032f62;
  --syntax-number: #005cc5;
  --syntax-class: #6f42c1;
  --syntax-punctuation: #24292e;
}

code[class*="language-"],
pre[class*="language-"] {
  color: var(--syntax-text);
  background: none;
  font-family: var(--font-family-mono);
  text-align: left;
  white-space: pre;
  word-spacing: normal;
  word-break: normal;
  word-wrap: normal;
  line-height: 1.6;
  tab-size: 4;
  hyphens: none;
}

pre[class*="language-"] {
  padding: var(--spacing-lg) var(--spacing-xl);
  margin: var(--spacing-xl) 0;
  overflow: auto;
  background: var(--syntax-bg);
  border: 1px solid var(--color-border);
  border-radius: 16px;
}

:not(pre)>code[class*="language-"],
pre[class*="language-"] {
  background: var(--syntax-bg);
}

/* Tokens */
.token.comment,
.token.prolog,
.token.doctype,
.token.cdata {
  color: var(--syntax-comment);
  font-style: italic;
}

.token.punctuation {
  color: var(--syntax-punctuation);
}

.token.namespace {
  opacity: .7;
}

.token.property,
.token.tag,
.token.constant,
.token.symbol,
.token.deleted {
  color: var(--syntax-keyword);
}

.token.boolean,
.token.number {
  color: var(--syntax-number);
}

.token.selector,
.token.attr-name,
.token.string,
.token.char,
.token.builtin,
.token.inserted {
  color: var(--syntax-string);
}

.token.operator,
.token.entity,
.token.url,
.language-css .token.string,
.style .token.string {
  color: var(--syntax-text);
}

.token.atrule,
.token.attr-value,
.token.keyword {
  color: var(--syntax-keyword);
}

.token.function,
.token.class-name {
  color: var(--syntax-function);
}

.token.regex,
.token.important,
.token.variable {
  color: var(--syntax-number);
}

.token.important,
.token.bold {
  font-weight: bold;
}

.token.italic {
  font-style: italic;
}

.token.entity {
  cursor: help;
}