/* ==========================================================================
   Crypto Earning Static Site - Master Stylesheet (Production-Ready)
   Architecture: Lightweight CSS3, Responsive Mobile-First, Zero Dependencies
   Color Palette:
     - Dark Navy Backgrounds: #0b111e (Primary), #131d31 (Secondary), #18243c (Card)
     - Border Elements: #243452
     - Typography: #f1f5f9 (Heading/Main), #94a3b8 (Muted Body), #64748b (Dim/Meta)
     - Accents: #00e5ff (Vibrant Cyan), #00e676 (Green), #ffb300 (Amber), #ff5252 (Red)
   ========================================================================== */

:root {
  --bg-primary: #0b111e;
  --bg-secondary: #131d31;
  --bg-card: #18243c;
  --bg-card-hover: #1e2d4b;
  --border-color: #243452;
  --border-subtle: rgba(36, 52, 82, 0.6);
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --text-dim: #64748b;
  --accent-cyan: #00e5ff;
  --accent-cyan-hover: #00b0ff;
  --accent-green: #00e676;
  --accent-amber: #ffb300;
  --accent-red: #ff5252;
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Helvetica Neue", sans-serif;
  --max-width: 1200px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --transition: all 0.2s ease-in-out;
}

/* --------------------------------------------------------------------------
   1. Global CSS Reset & Base Typography
   -------------------------------------------------------------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  background-color: var(--bg-primary);
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  color: var(--text-main);
  background-color: var(--bg-primary);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

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

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

a:hover, a:focus-visible {
  color: #ffffff;
  text-decoration: underline;
}

/* --------------------------------------------------------------------------
   2. Accessibility Skip Link
   -------------------------------------------------------------------------- */
.skip-link {
  position: absolute;
  top: -120px;
  left: 1.25rem;
  background: var(--accent-cyan);
  color: #0b111e;
  font-weight: 700;
  padding: 0.65rem 1.25rem;
  z-index: 9999;
  border-radius: var(--radius-sm);
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 1.25rem;
}

/* --------------------------------------------------------------------------
   3. Layout Container
   -------------------------------------------------------------------------- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.25rem;
  padding-right: 1.25rem;
}

/* --------------------------------------------------------------------------
   4. Header & Navigation Bar
   -------------------------------------------------------------------------- */
.site-header {
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(8px);
}

.header-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.875rem 1.25rem;
  max-width: var(--max-width);
  margin: 0 auto;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-main);
  text-decoration: none;
  letter-spacing: -0.01em;
}

.brand-logo:hover {
  text-decoration: none;
  color: var(--accent-cyan);
}

.brand-icon {
  width: 28px;
  height: 28px;
  fill: var(--accent-cyan);
  flex-shrink: 0;
}

.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-main);
  padding: 0.45rem 0.75rem;
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-size: 1.25rem;
  line-height: 1;
}

.nav-toggle:focus-visible {
  outline: 2px solid var(--accent-cyan);
}

.nav-menu {
  display: flex;
  align-items: center;
  list-style: none;
  gap: 1rem;
}

.nav-link {
  color: var(--text-muted);
  font-weight: 500;
  font-size: 0.95rem;
  text-decoration: none;
  padding: 0.35rem 0.65rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-link:hover, .nav-link.active {
  color: var(--accent-cyan);
  text-decoration: none;
  background-color: rgba(0, 229, 255, 0.08);
}

/* --------------------------------------------------------------------------
   5. Hero Section & Live Search Widget
   -------------------------------------------------------------------------- */
.hero-section {
  padding: 3.5rem 0 2.5rem;
  background: radial-gradient(circle at 85% 15%, rgba(0, 229, 255, 0.08), transparent 45%),
              radial-gradient(circle at 15% 20%, rgba(0, 230, 118, 0.05), transparent 40%);
  border-bottom: 1px solid var(--border-color);
}

.hero-title {
  font-size: 2.25rem;
  font-weight: 800;
  line-height: 1.2;
  margin-bottom: 1rem;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

.hero-title span {
  color: var(--accent-cyan);
}

.hero-desc {
  font-size: 1.1rem;
  color: var(--text-muted);
  max-width: 760px;
  margin-bottom: 1.5rem;
  line-height: 1.7;
}

.search-widget {
  max-width: 620px;
  margin-top: 1.5rem;
}

.search-form {
  position: relative;
  display: flex;
}

.search-input {
  width: 100%;
  padding: 0.85rem 1rem 0.85rem 2.85rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  background-color: var(--bg-secondary);
  color: var(--text-main);
  font-size: 1rem;
  transition: var(--transition);
}

.search-input:focus {
  outline: none;
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px rgba(0, 229, 255, 0.15);
}

.search-icon {
  position: absolute;
  left: 0.95rem;
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  fill: var(--text-dim);
  pointer-events: none;
}

/* --------------------------------------------------------------------------
   6. Grid Systems & Card Components
   -------------------------------------------------------------------------- */
.grid-categories, .grid-cards {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(285px, 1fr));
  gap: 1.35rem;
  margin: 1.5rem 0;
}

.category-card, .content-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 1.35rem;
  transition: var(--transition);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.category-card:hover, .content-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-cyan);
  background-color: var(--bg-card-hover);
  box-shadow: 0 6px 16px rgba(0, 0, 0, 0.25);
}

.card-title {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-main);
  font-weight: 700;
  line-height: 1.3;
}

.card-title a {
  color: inherit;
  text-decoration: none;
}

.card-title a:hover {
  color: var(--accent-cyan);
}

.card-desc {
  color: var(--text-muted);
  font-size: 0.925rem;
  margin-bottom: 1.15rem;
  flex-grow: 1;
  line-height: 1.6;
}

.card-badge {
  display: inline-block;
  font-size: 0.75rem;
  font-weight: 600;
  padding: 0.25rem 0.55rem;
  border-radius: var(--radius-sm);
  background: var(--bg-secondary);
  color: var(--accent-cyan);
  border: 1px solid var(--border-color);
  margin-bottom: 0.75rem;
  width: fit-content;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

/* --------------------------------------------------------------------------
   7. Buttons & User Actions
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.35rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: var(--transition);
  text-align: center;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-cyan-hover));
  color: #0b111e;
}

.btn-primary:hover {
  background: var(--accent-cyan-hover);
  color: #0b111e;
  text-decoration: none;
  box-shadow: 0 4px 14px rgba(0, 229, 255, 0.3);
}

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

.btn-secondary:hover {
  background: var(--border-color);
  color: #ffffff;
  text-decoration: none;
}

.btn-group {
  display: flex;
  gap: 0.85rem;
  flex-wrap: wrap;
  margin: 1.35rem 0;
}

/* --------------------------------------------------------------------------
   8. Platform Metadata Table (Landing Pages)
   -------------------------------------------------------------------------- */
.platform-meta-table {
  width: 100%;
  border-collapse: collapse;
  background-color: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-color);
  margin: 1.5rem 0;
}

.platform-meta-table th, .platform-meta-table td {
  padding: 0.9rem 1.15rem;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
  font-size: 0.95rem;
}

.platform-meta-table th {
  background-color: var(--bg-secondary);
  color: var(--text-muted);
  width: 35%;
  font-weight: 600;
}

.platform-meta-table tr:last-child th,
.platform-meta-table tr:last-child td {
  border-bottom: none;
}

/* --------------------------------------------------------------------------
   9. Callouts & Disclaimers
   -------------------------------------------------------------------------- */
.callout {
  padding: 1.35rem;
  border-radius: var(--radius-md);
  margin: 1.75rem 0;
  border-left: 4px solid;
}

.callout-info {
  background-color: rgba(0, 229, 255, 0.05);
  border-color: var(--accent-cyan);
}

.callout-warning {
  background-color: rgba(255, 179, 0, 0.07);
  border-color: var(--accent-amber);
}

.callout-title {
  font-weight: 700;
  font-size: 1.05rem;
  margin-bottom: 0.45rem;
}

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

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

/* --------------------------------------------------------------------------
   10. Advertising Safe Slot Containers
   -------------------------------------------------------------------------- */
.ad-slot-container {
  width: 100%;
  margin: 2rem 0;
  padding: 0.75rem 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  clear: both;
}

.ad-slot-banner {
  width: 100%;
  min-height: 90px;
  max-width: 728px;
  border: 1px dashed var(--border-color);
  background-color: rgba(19, 29, 49, 0.5);
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1rem;
}

.ad-slot-rectangle {
  width: 100%;
  min-height: 250px;
  max-width: 300px;
  border: 1px dashed var(--border-color);
  background-color: rgba(19, 29, 49, 0.5);
  border-radius: var(--radius-sm);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 1rem;
  margin: 1.5rem auto;
}

.ad-notice {
  font-size: 0.7rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 0.35rem;
}

.ad-instruction {
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   11. Main Content & Article Body Typography
   -------------------------------------------------------------------------- */
.main-content {
  flex: 1 0 auto;
  padding: 2.5rem 0;
}

.article-body {
  line-height: 1.75;
  color: var(--text-main);
}

.article-body h1 {
  font-size: 2.25rem;
  font-weight: 800;
  margin-bottom: 1rem;
  color: var(--text-main);
  letter-spacing: -0.02em;
}

.article-body h2 {
  font-size: 1.7rem;
  font-weight: 700;
  margin: 2.25rem 0 1rem;
  color: var(--text-main);
  border-bottom: 1px solid var(--border-color);
  padding-bottom: 0.5rem;
}

.article-body h3 {
  font-size: 1.3rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
  color: var(--accent-cyan);
}

.article-body p {
  margin-bottom: 1.25rem;
  color: #cbd5e1;
}

.article-body ul, .article-body ol {
  margin: 1rem 0 1.5rem 1.75rem;
  color: #cbd5e1;
}

.article-body li {
  margin-bottom: 0.5rem;
}

/* --------------------------------------------------------------------------
   12. FAQ Accordion Component
   -------------------------------------------------------------------------- */
.faq-accordion {
  margin: 2.25rem 0;
}

.faq-item {
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  margin-bottom: 0.75rem;
  background-color: var(--bg-card);
  overflow: hidden;
  transition: var(--transition);
}

.faq-question {
  width: 100%;
  text-align: left;
  padding: 1rem 1.25rem;
  background: none;
  border: none;
  color: var(--text-main);
  font-size: 1.05rem;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: color 0.2s ease;
}

.faq-question:hover {
  color: var(--accent-cyan);
}

.faq-answer {
  padding: 0 1.25rem 1.25rem;
  color: var(--text-muted);
  display: none;
  font-size: 0.95rem;
  border-top: 1px solid var(--border-subtle);
  padding-top: 0.85rem;
}

.faq-item.active .faq-answer {
  display: block;
}

.faq-icon {
  font-size: 1.35rem;
  color: var(--accent-cyan);
  transition: transform 0.2s ease;
  line-height: 1;
}

.faq-item.active .faq-icon {
  transform: rotate(45deg);
}

/* --------------------------------------------------------------------------
   13. Breadcrumb Navigation
   -------------------------------------------------------------------------- */
.breadcrumb-nav {
  margin-bottom: 1.5rem;
  font-size: 0.85rem;
  color: var(--text-dim);
}

.breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  list-style: none;
  gap: 0.5rem;
}

.breadcrumb-list li::after {
  content: "/";
  margin-left: 0.5rem;
  color: var(--text-dim);
}

.breadcrumb-list li:last-child::after {
  content: "";
}

/* --------------------------------------------------------------------------
   14. Site Footer
   -------------------------------------------------------------------------- */
.site-footer {
  background-color: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 3.5rem 0 1.75rem;
  margin-top: auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 2.25rem;
  margin-bottom: 2.25rem;
}

.footer-heading {
  font-size: 0.95rem;
  font-weight: 700;
  margin-bottom: 1.15rem;
  color: var(--text-main);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.footer-links {
  list-style: none;
}

.footer-links li {
  margin-bottom: 0.65rem;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.925rem;
}

.footer-links a:hover {
  color: var(--accent-cyan);
}

.footer-bottom {
  border-top: 1px solid var(--border-color);
  padding-top: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  font-size: 0.85rem;
  color: var(--text-dim);
  text-align: center;
}

/* --------------------------------------------------------------------------
   15. Responsive Media Queries (Mobile-First Optimization)
   -------------------------------------------------------------------------- */
@media (max-width: 820px) {
  .nav-toggle {
    display: block;
  }

  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    width: 100%;
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border-color);
    flex-direction: column;
    padding: 1.25rem;
    gap: 0.85rem;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.4);
  }

  .nav-menu.is-active {
    display: flex;
  }

  .hero-title {
    font-size: 1.85rem;
  }

  .hero-desc {
    font-size: 1rem;
  }

  .grid-categories, .grid-cards {
    grid-template-columns: 1fr;
  }

  .platform-meta-table th, .platform-meta-table td {
    display: block;
    width: 100%;
  }

  .platform-meta-table th {
    background-color: rgba(36, 52, 82, 0.4);
    border-bottom: none;
  }
}