/* Base Styles - Global layout and typography */
/* Optimized for performance and Core Web Vitals */

:root {
  /* Color Palette - Light Mode */
  --color-primary: #3b82f6;
  --color-primary-dark: #2563eb;
  --color-primary-light: #60a5fa;
  --color-accent: #8b5cf6;
  --color-accent-dark: #7c3aed;

  --color-text: #111827;
  --color-text-medium: #374151;
  --color-text-light: #6b7280;
  --color-text-lighter: #9ca3af;

  --color-bg: #ffffff;
  --color-bg-light: #f9fafb;
  --color-bg-lighter: #f3f4f6;

  --color-border: #e5e7eb;
  --color-border-light: #f3f4f6;

  --color-success: #10b981;
  --color-success-light: #d1fae5;
  --color-error: #ef4444;
  --color-warning: #f59e0b;
}

/* Dark Mode */
[data-theme="dark"] {
  --color-primary: #60a5fa;
  --color-primary-dark: #3b82f6;
  --color-primary-light: #93c5fd;
  --color-accent: #a78bfa;
  --color-accent-dark: #8b5cf6;

  --color-text: #f9fafb;
  --color-text-medium: #e5e7eb;
  --color-text-light: #9ca3af;
  --color-text-lighter: #6b7280;

  --color-bg: #111827;
  --color-bg-light: #1f2937;
  --color-bg-lighter: #374151;

  --color-border: #374151;
  --color-border-light: #1f2937;

  --color-success: #34d399;
  --color-success-light: #064e3b;
  --color-error: #f87171;
  --color-warning: #fbbf24;
}

:root {

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

  /* Typography */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", Monaco, "Cascadia Code", "Roboto Mono", Consolas, monospace;

  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Effects */
  --border-radius: 12px;
  --border-radius-sm: 8px;
  --border-radius-lg: 16px;

  --shadow-xs: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px -1px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -4px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);

  --transition-fast: 150ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 300ms ease;
}

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

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

body {
  font-family: var(--font-sans);
  line-height: 1.7;
  color: var(--color-text);
  background: var(--color-bg);
  background-attachment: fixed;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color var(--transition-base), color var(--transition-base);
}

body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(to bottom, var(--color-bg) 0%, var(--color-bg-light) 100%);
  z-index: -1;
  transition: opacity var(--transition-base);
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  line-height: 1.2;
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--spacing-sm);
  color: var(--color-text);
  letter-spacing: -0.02em;
}

h1 {
  font-size: 2rem;
  margin-bottom: var(--spacing-md);
  font-weight: 800;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

h2 {
  font-size: 1.5rem;
  color: var(--color-text);
  font-weight: var(--font-weight-bold);
}

h3 {
  font-size: 1.25rem;
  color: var(--color-text-medium);
  font-weight: var(--font-weight-semibold);
}

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

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

a:hover {
  color: var(--color-primary-dark);
  text-decoration: none;
}

a:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
  border-radius: 2px;
}

ul, ol {
  margin-bottom: var(--spacing-md);
  padding-left: var(--spacing-lg);
  color: var(--color-text-medium);
}

li {
  margin-bottom: var(--spacing-xs);
  line-height: 1.7;
}

strong {
  font-weight: var(--font-weight-semibold);
  color: var(--color-text);
}

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

.container-narrow {
  max-width: 800px;
}

/* Header */
header {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
  padding: var(--spacing-lg) 0;
  box-shadow: var(--shadow-xs);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(8px);
  transition: padding var(--transition-base),
              background-color var(--transition-base),
              border-color var(--transition-base),
              box-shadow var(--transition-base);
}

[data-theme="light"] header {
  background-color: rgba(255, 255, 255, 0.95);
}

[data-theme="dark"] header {
  background-color: rgba(17, 24, 39, 0.95);
}

/* Scrolled Header - Compact State */
header.scrolled {
  padding: var(--spacing-sm) 0;
  box-shadow: var(--shadow-md);
}

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

header .header-content {
  flex: 1;
}

header h1 {
  font-size: 1.5rem;
  margin-bottom: 0.25rem;
  background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  transition: font-size var(--transition-base), margin var(--transition-base);
}

header.scrolled h1 {
  font-size: 1.25rem;
  margin-bottom: 0;
}

header p {
  margin: 0;
  font-size: 0.875rem;
  transition: opacity var(--transition-base),
              max-height var(--transition-base),
              margin var(--transition-base);
  max-height: 2rem;
  opacity: 1;
  overflow: hidden;
}

header.scrolled p {
  max-height: 0;
  opacity: 0;
  margin: 0;
}

/* Main Content */
main {
  flex: 1;
  padding: var(--spacing-lg) 0;
}

/* Footer */
footer {
  background: var(--color-bg-light);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
  margin-top: var(--spacing-2xl);
  font-size: 0.875rem;
  color: var(--color-text-light);
}

[data-theme="light"] footer {
  background: linear-gradient(to top, var(--color-bg-light) 0%, var(--color-bg) 100%);
}

[data-theme="dark"] footer {
  background: var(--color-bg-lighter);
}

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

footer a {
  color: var(--color-text-light);
  font-weight: var(--font-weight-normal);
  transition: color var(--transition-fast);
}

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

/* Ad Containers - Reserved Space to Prevent CLS */
.ad-container {
  background: var(--color-bg-light);
  border: 1px solid var(--color-border-light);
  border-radius: var(--border-radius-sm);
  margin: var(--spacing-xl) 0;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 250px;
  width: 100%;
  position: relative;
  overflow: hidden;
}

[data-theme="light"] .ad-container {
  background: linear-gradient(135deg, #f9fafb 0%, #f3f4f6 100%);
}

[data-theme="dark"] .ad-container {
  background: var(--color-bg-lighter);
}

.ad-container::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(45deg, transparent 30%, rgba(255,255,255,0.1) 50%, transparent 70%);
  opacity: 0.5;
}

[data-theme="light"] .ad-container::before {
  background: linear-gradient(45deg, transparent 30%, rgba(255,255,255,0.3) 50%, transparent 70%);
}

.ad-container-horizontal {
  min-height: 90px;
  max-width: 728px;
  margin-left: auto;
  margin-right: auto;
}

.ad-container-square {
  min-height: 250px;
  max-width: 300px;
}

/* Sidebar Ads - Desktop Only */
.ad-sidebar {
  display: none; /* Hidden by default (mobile/tablet) */
  position: fixed;
  top: 120px; /* Below header */
  z-index: 50;
}

.ad-sidebar-left {
  left: 20px;
}

.ad-sidebar-right {
  right: 20px;
}

.ad-container-vertical {
  min-height: 600px;
  width: 160px;
  max-width: 160px;
  margin: 0;
}

/* Utility Classes */
.text-center {
  text-align: center;
}

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

.mb-sm {
  margin-bottom: var(--spacing-sm);
}

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

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

.mt-lg {
  margin-top: var(--spacing-lg);
}

/* Dark Mode Toggle */
.theme-toggle {
  background: var(--color-bg-light);
  border: 2px solid var(--color-border);
  border-radius: 50%;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast),
              width var(--transition-base),
              height var(--transition-base);
  flex-shrink: 0;
  position: relative;
  overflow: hidden;
}

.theme-toggle:hover {
  background: var(--color-bg-lighter);
  border-color: var(--color-primary);
  transform: scale(1.05);
}

.theme-toggle:active {
  transform: scale(0.95);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.theme-toggle svg {
  width: 20px;
  height: 20px;
  transition: all var(--transition-base),
              width var(--transition-base),
              height var(--transition-base);
  position: absolute;
}

.theme-toggle .sun-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

.theme-toggle .moon-icon {
  opacity: 0;
  transform: rotate(180deg) scale(0);
}

[data-theme="dark"] .theme-toggle .sun-icon {
  opacity: 0;
  transform: rotate(-180deg) scale(0);
}

[data-theme="dark"] .theme-toggle .moon-icon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

.theme-toggle svg {
  stroke: var(--color-text-medium);
  transition: stroke var(--transition-fast);
}

.theme-toggle:hover svg {
  stroke: var(--color-primary);
}

/* Responsive - Mobile First */
@media (max-width: 768px) {
  :root {
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 2.5rem;
  }

  h1 {
    font-size: 1.75rem;
  }

  h2 {
    font-size: 1.25rem;
  }

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

  .content-section {
    padding: var(--spacing-md);
  }

  .ad-container {
    min-height: 90px;
    border: 2px dashed var(--color-border);
  }

  .ad-container-horizontal {
    min-height: 90px;
  }

  .ad-container .text-muted {
    color: var(--color-text);
    font-weight: 500;
  }

  header {
    padding: var(--spacing-md) 0;
  }

  header.scrolled {
    padding: var(--spacing-xs) 0;
  }

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

  header h1 {
    font-size: 1.25rem;
  }

  header.scrolled h1 {
    font-size: 1.125rem;
  }

  .theme-toggle {
    width: 40px;
    height: 40px;
  }

  header.scrolled .theme-toggle {
    width: 36px;
    height: 36px;
  }

  .theme-toggle svg {
    width: 18px;
    height: 18px;
  }

  header.scrolled .theme-toggle svg {
    width: 16px;
    height: 16px;
  }

  .disclaimer {
    padding: var(--spacing-md);
  }

  .disclaimer::before {
    position: static;
    display: block;
    margin-bottom: var(--spacing-xs);
  }

  .disclaimer strong,
  .disclaimer p {
    margin-left: 0;
  }
}

/* Tablet */
@media (min-width: 769px) and (max-width: 1024px) {
  h1 {
    font-size: 2.25rem;
  }

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

  header h1 {
    font-size: 1.5rem;
  }

  header.scrolled h1 {
    font-size: 1.375rem;
  }
}

/* Desktop */
@media (min-width: 1025px) {
  h1 {
    font-size: 2.75rem;
  }

  .content-section {
    padding: var(--spacing-2xl);
  }

  header h1 {
    font-size: 1.75rem;
  }

  header.scrolled h1 {
    font-size: 1.5rem;
  }
}

/* Large Desktop - Sidebar Ads Visible */
@media (min-width: 1440px) {
  .ad-sidebar {
    display: block;
  }

  /* Adjust sidebar position based on scroll */
  header.scrolled ~ main .ad-sidebar {
    top: 80px; /* Adjust for smaller scrolled header */
  }
}

/* Extra Large Desktop - Wider Sidebar Ads */
@media (min-width: 1920px) {
  .ad-sidebar-left {
    left: calc((100vw - 1200px) / 2 - 180px);
  }

  .ad-sidebar-right {
    right: calc((100vw - 1200px) / 2 - 180px);
  }
}

/* Content Sections */
.content-section {
  background: var(--color-bg);
  padding: var(--spacing-xl);
  margin-bottom: var(--spacing-lg);
  border-radius: var(--border-radius);
  border: 1px solid var(--color-border-light);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

[data-theme="light"] .content-section {
  background: white;
}

[data-theme="dark"] .content-section {
  background: var(--color-bg-light);
}

.content-section:hover {
  box-shadow: var(--shadow-md);
  border-color: var(--color-border);
}

.content-section h2 {
  margin-top: 0;
  padding-bottom: var(--spacing-sm);
  border-bottom: 2px solid var(--color-border-light);
  margin-bottom: var(--spacing-md);
}

.content-section h3 {
  margin-top: var(--spacing-lg);
}

/* Links List */
.links-list {
  list-style: none;
  padding: 0;
}

.links-list li {
  padding: 0;
  margin-bottom: 0.5rem;
}

.links-list a {
  display: block;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--color-bg-light);
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--color-border-light);
  transition: all var(--transition-fast);
}

[data-theme="light"] .links-list a {
  background: var(--color-bg-light);
  border: 1px solid var(--color-border-light);
}

[data-theme="dark"] .links-list a {
  background: var(--color-bg-lighter);
  border: 1px solid var(--color-border);
}

.links-list a:hover {
  background: var(--color-bg);
  border-color: var(--color-primary);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

[data-theme="light"] .links-list a:hover {
  background: white;
}

[data-theme="dark"] .links-list a:hover {
  background: var(--color-bg);
}

/* Disclaimer */
.disclaimer {
  background: linear-gradient(135deg, #fffbeb 0%, #fef3c7 100%);
  border: 2px solid #fbbf24;
  border-radius: var(--border-radius);
  padding: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
  font-size: 0.875rem;
  position: relative;
  box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .disclaimer {
  background: linear-gradient(135deg, #451a03 0%, #78350f 100%);
  border-color: #d97706;
}

.disclaimer::before {
  content: '⚠️';
  position: absolute;
  top: var(--spacing-md);
  left: var(--spacing-md);
  font-size: 1.5rem;
  opacity: 0.7;
}

.disclaimer strong {
  display: block;
  margin-bottom: var(--spacing-sm);
  margin-left: 2.5rem;
  font-size: 1rem;
  color: #92400e;
}

[data-theme="dark"] .disclaimer strong {
  color: #fcd34d;
}

.disclaimer p {
  margin-left: 2.5rem;
  margin-bottom: 0;
  color: #78350f;
  line-height: 1.6;
}

[data-theme="dark"] .disclaimer p {
  color: #fde68a;
}