/* =====================================================
   GLOBAL STYLES - JUNN'S BLOG
   =====================================================
   Base styles that apply across all pages of the blog.
   Includes typography, colors, and common components.
   ===================================================== */

/* -----------------------------------------------------
   CSS VARIABLES / THEME
   ----------------------------------------------------- */

:root {
  /* Colors - Light Mode (Default) */
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-secondary: #64748b;
  
  --color-background: #ffffff;
  --color-surface: #f8fafc;
  --color-text: #1e293b;
  --color-text-muted: #64748b;
  --color-border: #e2e8f0;
  
  --color-success: #16a34a;
  --color-error: #dc2626;
  --color-warning: #ca8a04;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* Typography */
  --font-family-base: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  --font-family-mono: 'SF Mono', Monaco, Consolas, monospace;
  
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  
  /* Borders */
  --border-radius-sm: 0.25rem;
  --border-radius-md: 0.5rem;
  --border-radius-lg: 0.75rem;
  --border-radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  
  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

/* Dark Mode Support */
@media (prefers-color-scheme: dark) {
  :root {
    --color-background: #0f172a;
    --color-surface: #1e293b;
    --color-text: #f1f5f9;
    --color-text-muted: #94a3b8;
    --color-border: #334155;
    
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
  }
}

/* Force dark mode class */
[data-theme="dark"] {
  --color-background: #0f172a;
  --color-surface: #1e293b;
  --color-text: #f1f5f9;
  --color-text-muted: #94a3b8;
  --color-border: #334155;
  
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
}

/* -----------------------------------------------------
   RESET & BASE STYLES
   ----------------------------------------------------- */

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

[hidden] {
  display: none !important;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family-base);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--color-text);
  background-color: var(--color-background);
  min-height: 100vh;
}

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

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
}

ul, ol {
  list-style: none;
}

/* -----------------------------------------------------
   LAYOUT UTILITIES
   ----------------------------------------------------- */

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

.items-center {
  align-items: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-sm {
  gap: var(--spacing-sm);
}

.gap-md {
  gap: var(--spacing-md);
}

.gap-lg {
  gap: var(--spacing-lg);
}

/* -----------------------------------------------------
   TYPOGRAPHY
   ----------------------------------------------------- */

h1, h2, h3, h4, h5, h6 {
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: var(--spacing-md);
}

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
h3 { font-size: var(--text-2xl); }
h4 { font-size: var(--text-xl); }
h5 { font-size: var(--text-lg); }
h6 { font-size: var(--text-base); }

p {
  margin-bottom: var(--spacing-md);
}

/* -----------------------------------------------------
   NAVIGATION BAR
   ----------------------------------------------------- */

.navbar {
  background-color: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
}

.navbar-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-text);
}

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

.nav-links {
  display: flex;
  gap: var(--spacing-lg);
}

.nav-link {
  color: var(--color-text-muted);
  font-weight: 500;
  padding: var(--spacing-sm) 0;
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--color-primary);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-primary);
  transition: width var(--transition-normal);
}

.nav-link:hover::after,
.nav-link.active::after {
  width: 100%;
}

/* Mobile Navigation Toggle */
.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: var(--spacing-sm);
}

.menu-bar {
  width: 25px;
  height: 3px;
  background-color: var(--color-text);
  border-radius: var(--border-radius-full);
  transition: transform var(--transition-fast), opacity var(--transition-fast);
}

.mobile-menu-toggle .menu-bar:nth-child(2) {
  width: 18px;
  margin-left: auto;
}

/* -----------------------------------------------------
   BUTTONS
   ----------------------------------------------------- */

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

.btn-primary {
  background-color: var(--color-primary);
  color: white;
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--color-primary-hover);
}

.btn-secondary {
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  color: var(--color-text);
}

.btn-secondary:hover:not(:disabled) {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.btn-danger {
  background-color: var(--color-error);
  color: white;
}

.btn-danger:hover:not(:disabled) {
  background-color: #b91c1c;
}

.btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* -----------------------------------------------------
   FORMS
   ----------------------------------------------------- */

.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--spacing-md);
  font-size: var(--text-base);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  background-color: var(--color-background);
  color: var(--color-text);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea {
  min-height: 200px;
  resize: vertical;
}

/* -----------------------------------------------------
   ALERTS / NOTIFICATIONS
   ----------------------------------------------------- */

.alert {
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--border-radius-md);
  margin-bottom: var(--spacing-md);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.alert-success {
  background-color: #dcfce7;
  color: #16a34a;
  border-left: 4px solid #16a34a;
}

.alert-error {
  background-color: #fee2e2;
  color: #dc2626;
  border-left: 4px solid #dc2626;
}

.alert-warning {
  background-color: #fef3c7;
  color: #ca8a04;
  border-left: 4px solid #ca8a04;
}

/* -----------------------------------------------------
   CARDS
   ----------------------------------------------------- */

.card {
  background-color: var(--color-surface);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
  transition: box-shadow var(--transition-fast), transform var(--transition-fast);
}

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

/* -----------------------------------------------------
   POST CARDS (Blog Listing)
   ----------------------------------------------------- */

.post-card {
  background-color: var(--color-surface);
  border-radius: var(--border-radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-fast);
}

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

.pinned-badge {
  display: inline-block;
  background-color: #fef3c7;
  color: #ca8a04;
  font-size: var(--text-xs);
  font-weight: 600;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-full);
  margin-bottom: var(--spacing-sm);
}

.post-title {
  display: block;
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--color-text);
  margin-bottom: var(--spacing-xs);
}

.post-meta {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.reading-time {
  font-weight: 500;
}

.post-tags {
  margin-top: var(--spacing-md);
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.tag-link {
  font-size: var(--text-xs);
  color: var(--color-primary);
  background-color: rgba(37, 99, 235, 0.1);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-full);
}

.tag-link:hover {
  color: var(--color-primary-hover);
  background-color: rgba(37, 99, 235, 0.15);
}

/* -----------------------------------------------------
   POST DETAIL PAGE
   ----------------------------------------------------- */

.post-detail {
  max-width: 800px;
  margin: 0 auto;
}

.post-header {
  margin-bottom: var(--spacing-xl);
}

.post-meta-detail {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  flex-wrap: wrap;
}

.meta-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
}

.post-content {
  font-size: var(--text-lg);
  line-height: 1.8;
}

.post-content h2,
.post-content h3,
.post-content h4 {
  margin-top: var(--spacing-xl);
  margin-bottom: var(--spacing-md);
}

.post-content p {
  margin-bottom: var(--spacing-lg);
}

.post-content code {
  background-color: var(--color-surface);
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  font-family: var(--font-family-mono);
  font-size: var(--text-sm);
}

.post-content pre {
  background-color: var(--color-surface);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-md);
  overflow-x: auto;
  margin-bottom: var(--spacing-lg);
}

.post-content pre code {
  background: none;
  padding: 0;
}

.post-content ul,
.post-content ol {
  margin-bottom: var(--spacing-lg);
  padding-left: var(--spacing-xl);
}

.post-content li {
  margin-bottom: var(--spacing-sm);
}

.post-tags-section {
  margin-top: var(--spacing-2xl);
  padding-top: var(--spacing-xl);
  border-top: 1px solid var(--color-border);
}

.tags-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
  list-style: none;
}

.tag-link-detail {
  font-size: var(--text-sm);
  color: var(--color-primary);
}

.post-footer {
  margin-top: var(--spacing-2xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* -----------------------------------------------------
   PAGINATION
   ----------------------------------------------------- */

.pagination-controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-xl);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
}

.pagination-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 40px;
  height: 40px;
  padding: 0 var(--spacing-sm);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  transition: all var(--transition-fast);
}

.pagination-btn:hover:not(:disabled) {
  background-color: var(--color-background);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.pagination-btn.current {
  background-color: var(--color-primary);
  color: white;
  border-color: var(--color-primary);
}

.pagination-btn.ellipsis {
  min-width: auto;
  padding: 0 var(--spacing-xs);
}

.page-info {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* -----------------------------------------------------
   SEARCH COMPONENT
   ----------------------------------------------------- */

.search-container {
  position: relative;
  max-width: 600px;
}

#search-input {
  width: 100%;
  padding: var(--spacing-md) var(--spacing-lg);
  font-size: var(--text-base);
  border: 2px solid var(--color-border);
  border-radius: var(--border-radius-full);
  background-color: var(--color-surface);
  color: var(--color-text);
}

#search-input:focus {
  outline: none;
  border-color: var(--color-primary);
}

.search-header {
  margin-bottom: var(--spacing-lg);
}

.search-header h3 {
  font-size: var(--text-xl);
  margin-bottom: var(--spacing-sm);
}

.loading,
.search-error {
  text-align: center;
  padding: var(--spacing-xl);
  color: var(--color-text-muted);
}

.loading-spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  margin: 0 auto;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* -----------------------------------------------------
   EMPTY STATE
   ----------------------------------------------------- */

.empty-state {
  text-align: center;
  padding: var(--spacing-2xl) var(--spacing-lg);
  color: var(--color-text-muted);
}

.empty-state h3 {
  font-size: var(--text-xl);
  margin-bottom: var(--spacing-sm);
}

/* -----------------------------------------------------
   FOOTER
   ----------------------------------------------------- */

.footer {
  background-color: var(--color-surface);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
  margin-top: var(--spacing-2xl);
}

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

.footer-text {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* -----------------------------------------------------
   RESPONSIVE DESIGN
   ----------------------------------------------------- */

@media (max-width: 768px) {
  :root {
    --spacing-xl: 1.5rem;
    --spacing-2xl: 2rem;
  }

  .mobile-menu-toggle {
    display: flex;
  }

  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    flex-direction: column;
    padding: var(--spacing-md);
    gap: var(--spacing-sm);
    
    display: none;
  }

  .nav-links.active {
    display: flex;
  }

  .navbar-content {
    position: relative;
  }

  .container {
    padding: 0 var(--spacing-sm);
  }

  h1 { font-size: var(--text-3xl); }
  h2 { font-size: var(--text-2xl); }
  
  .post-detail {
    padding: 0 var(--spacing-md);
  }
  
  .footer-content {
    flex-direction: column;
    text-align: center;
  }
}

/* -----------------------------------------------------
   UTILITY CLASSES
   ----------------------------------------------------- */

.text-center { text-align: center; }
.text-right { text-align: right; }
.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }

.hidden { display: none !important; }
.visible { visibility: visible; opacity: 1; }
.invisible { visibility: hidden; }