/* ==========================================================================
   BambooFurnitureTalk - Cloudflare Pages Landing Page Stylesheet
   Theme: Eco-Modern / Botanical Luxury & Structural Engineering
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Variables & Design Tokens
   -------------------------------------------------------------------------- */
:root {
  /* Botanical Eco Palette */
  --color-primary-dark: #081c15;
  --color-primary-deep: #1b4332;
  --color-primary-forest: #2d6a4f;
  --color-primary-leaf: #40916c;
  --color-primary-mint: #52b788;
  --color-primary-light: #74c69d;
  --color-accent-amber: #b45309;
  --color-accent-gold: #d97706;
  --color-accent-honey: #f59e0b;
  --color-accent-sand: #fef3c7;
  --color-accent-sage: #d8f3dc;

  /* Neutrals & Surfaces */
  --bg-page: #fafcf8;
  --bg-card: #ffffff;
  --bg-subtle: #f2f7f0;
  --bg-tinted: #e8f4e5;
  --text-main: #1a2419;
  --text-muted: #4a5d4e;
  --text-light: #718774;
  --border-light: #e0ebd9;
  --border-accent: rgba(45, 106, 79, 0.25);

  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(27, 67, 50, 0.05);
  --shadow-md: 0 8px 24px rgba(27, 67, 50, 0.09);
  --shadow-lg: 0 16px 44px rgba(27, 67, 50, 0.13);
  --shadow-glow: 0 0 25px rgba(64, 145, 108, 0.22);

  /* Typography */
  --font-heading: 'Outfit', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

  /* Transitions */
  --transition-smooth: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  color: var(--text-main);
  background-color: var(--bg-page);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

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

a:hover {
  color: var(--color-accent-amber);
}

/* --------------------------------------------------------------------------
   Reading Progress Bar
   -------------------------------------------------------------------------- */
#reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  width: 0%;
  background: linear-gradient(90deg, var(--color-primary-mint), var(--color-accent-honey));
  z-index: 9999;
  transition: width 0.1s linear;
}

/* --------------------------------------------------------------------------
   Navigation Bar
   -------------------------------------------------------------------------- */
.navbar {
  position: sticky;
  top: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-light);
  z-index: 1000;
  padding: 0.9rem 0;
  transition: var(--transition-smooth);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--color-primary-deep);
  text-decoration: none;
}

.brand-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--color-primary-deep), var(--color-primary-leaf));
  border-radius: 8px;
  color: #ffffff;
  font-size: 1.15rem;
  box-shadow: 0 2px 8px rgba(27, 67, 50, 0.25);
}

.brand-logo span span {
  color: var(--color-accent-amber);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.8rem;
  list-style: none;
}

.nav-links a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-muted);
}

.nav-links a:hover {
  color: var(--color-primary-deep);
}

.nav-cta {
  background: linear-gradient(135deg, var(--color-primary-deep), var(--color-primary-forest));
  color: #ffffff !important;
  font-weight: 600;
  padding: 0.55rem 1.2rem;
  border-radius: 50px;
  box-shadow: 0 4px 14px rgba(27, 67, 50, 0.2);
  transition: var(--transition-smooth);
}

.nav-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(27, 67, 50, 0.3);
}

/* --------------------------------------------------------------------------
   Hero Section
   -------------------------------------------------------------------------- */
.hero-section {
  position: relative;
  background: linear-gradient(180deg, #edf6ea 0%, #fafcf8 100%);
  padding: 5rem 1.5rem 4rem;
  border-bottom: 1px solid var(--border-light);
  overflow: hidden;
}

.hero-pattern {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-image: radial-gradient(circle at 10% 20%, rgba(64, 145, 108, 0.08) 0%, transparent 40%),
                    radial-gradient(circle at 90% 80%, rgba(217, 119, 6, 0.06) 0%, transparent 45%);
  pointer-events: none;
}

.hero-container {
  max-width: 1080px;
  margin: 0 auto;
  position: relative;
  z-index: 2;
  text-align: center;
}

.hero-badge-wrap {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(45, 106, 79, 0.1);
  border: 1px solid rgba(45, 106, 79, 0.22);
  padding: 0.4rem 1.1rem;
  border-radius: 50px;
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-primary-deep);
  margin-bottom: 1.5rem;
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2.2rem, 4.8vw, 3.4rem);
  font-weight: 800;
  color: var(--color-primary-dark);
  line-height: 1.2;
  margin-bottom: 1.25rem;
  letter-spacing: -0.02em;
}

.hero-title span {
  background: linear-gradient(135deg, var(--color-primary-deep) 0%, var(--color-accent-amber) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.22rem);
  color: var(--text-muted);
  max-width: 840px;
  margin: 0 auto 2.5rem;
  font-weight: 400;
  line-height: 1.65;
}

.hero-meta-bar {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 1.8rem;
  flex-wrap: wrap;
  margin-bottom: 3rem;
  font-size: 0.88rem;
  color: var(--text-light);
}

.hero-meta-item {
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

/* Hero Stats Grid */
.hero-stats-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.stat-card {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.75rem 1.25rem;
  box-shadow: var(--shadow-sm);
  text-align: left;
  position: relative;
  overflow: hidden;
  transition: var(--transition-smooth);
}

.stat-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--color-primary-mint);
  transition: var(--transition-smooth);
}

.stat-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
}

.stat-card:hover::before {
  background: var(--color-accent-amber);
}

.stat-number {
  font-family: var(--font-heading);
  font-size: 2.1rem;
  font-weight: 800;
  color: var(--color-primary-deep);
  line-height: 1;
  margin-bottom: 0.45rem;
}

.stat-label {
  font-size: 0.86rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.35rem;
}

.stat-desc {
  font-size: 0.84rem;
  color: var(--text-light);
  line-height: 1.45;
}

/* --------------------------------------------------------------------------
   Layout & Article Structure
   -------------------------------------------------------------------------- */
.main-wrapper {
  max-width: 1160px;
  margin: 0 auto;
  padding: 3.5rem 1.5rem 5rem;
}

.article-layout {
  display: grid;
  grid-template-columns: 290px 1fr;
  gap: 3.5rem;
  align-items: start;
}

/* Sticky Sidebar Table of Contents */
.toc-sidebar {
  position: sticky;
  top: 90px;
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.toc-title {
  font-family: var(--font-heading);
  font-size: 1rem;
  font-weight: 700;
  color: var(--color-primary-dark);
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toc-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
}

.toc-list li a {
  font-size: 0.86rem;
  color: var(--text-muted);
  display: block;
  padding: 0.35rem 0.6rem;
  border-radius: 6px;
  line-height: 1.4;
  border-left: 2px solid transparent;
}

.toc-list li a:hover {
  background: var(--bg-subtle);
  color: var(--color-primary-deep);
  border-left-color: var(--color-primary-forest);
}

.sidebar-cta-box {
  margin-top: 1.8rem;
  background: linear-gradient(135deg, var(--bg-tinted), var(--bg-subtle));
  border: 1px dashed var(--color-primary-mint);
  border-radius: var(--radius-sm);
  padding: 1.15rem;
  text-align: center;
}

.sidebar-cta-box h4 {
  font-size: 0.92rem;
  color: var(--color-primary-deep);
  font-weight: 700;
  margin-bottom: 0.4rem;
}

.sidebar-cta-box p {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.85rem;
  line-height: 1.4;
}

.sidebar-cta-box .btn-calc {
  display: inline-block;
  font-size: 0.82rem;
  font-weight: 600;
  padding: 0.45rem 1rem;
  background: var(--color-primary-deep);
  color: #ffffff;
  border-radius: 50px;
}

/* --------------------------------------------------------------------------
   Article Content Sections
   -------------------------------------------------------------------------- */
.article-content {
  min-width: 0;
}

.content-section {
  margin-bottom: 4rem;
  scroll-margin-top: 100px;
}

.content-section h2 {
  font-family: var(--font-heading);
  font-size: clamp(1.6rem, 3vw, 2.1rem);
  font-weight: 700;
  color: var(--color-primary-dark);
  line-height: 1.3;
  margin-bottom: 1.15rem;
  padding-bottom: 0.65rem;
  border-bottom: 2px solid var(--bg-tinted);
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.content-section h3 {
  font-family: var(--font-heading);
  font-size: 1.3rem;
  font-weight: 600;
  color: var(--color-primary-deep);
  margin: 1.8rem 0 0.8rem;
}

.content-section p {
  font-size: 1.02rem;
  color: var(--text-main);
  line-height: 1.8;
  margin-bottom: 1.25rem;
}

.lead-p {
  font-size: 1.12rem;
  color: var(--text-muted);
  line-height: 1.75;
}

/* Inline Featured Links */
.guide-link {
  font-weight: 600;
  color: var(--color-primary-deep);
  border-bottom: 2px solid var(--color-primary-mint);
  padding-bottom: 1px;
}

.guide-link:hover {
  color: var(--color-accent-amber);
  border-bottom-color: var(--color-accent-honey);
}

/* Callout Highlights */
.callout-box {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  border: 1px solid var(--border-light);
  border-left: 5px solid var(--color-primary-forest);
  padding: 1.5rem 1.75rem;
  margin: 2rem 0;
  box-shadow: var(--shadow-sm);
}

.callout-box.amber {
  border-left-color: var(--color-accent-amber);
  background: #fffdf9;
}

.callout-header {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 1rem;
  color: var(--color-primary-deep);
  margin-bottom: 0.6rem;
}

.callout-box.amber .callout-header {
  color: var(--color-accent-amber);
}

.callout-box p {
  margin-bottom: 0;
  font-size: 0.95rem;
  color: var(--text-muted);
}

/* Key Takeaway Grid */
.takeaway-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
  margin: 2rem 0;
}

.takeaway-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
}

.takeaway-item h4 {
  font-size: 0.98rem;
  font-weight: 700;
  color: var(--color-primary-deep);
  margin-bottom: 0.35rem;
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.takeaway-item p {
  font-size: 0.88rem;
  margin-bottom: 0;
  color: var(--text-muted);
  line-height: 1.5;
}

/* Data Table Styling */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  margin: 2.2rem 0;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-light);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  background: var(--bg-card);
  font-size: 0.92rem;
}

.data-table th {
  background: var(--color-primary-deep);
  color: #ffffff;
  padding: 1rem 1.15rem;
  font-weight: 600;
  font-family: var(--font-heading);
  letter-spacing: 0.02em;
}

.data-table td {
  padding: 0.95rem 1.15rem;
  border-bottom: 1px solid var(--border-light);
  color: var(--text-main);
  vertical-align: middle;
}

.data-table tr:last-child td {
  border-bottom: none;
}

.data-table tr:nth-child(even) td {
  background-color: var(--bg-subtle);
}

.badge-tag {
  display: inline-block;
  padding: 0.25rem 0.65rem;
  border-radius: 50px;
  font-size: 0.75rem;
  font-weight: 700;
}

.badge-green {
  background: var(--color-accent-sage);
  color: var(--color-primary-deep);
}

.badge-amber {
  background: var(--color-accent-sand);
  color: var(--color-accent-amber);
}

/* --------------------------------------------------------------------------
   Interactive Widget Box
   -------------------------------------------------------------------------- */
.widget-card {
  background: linear-gradient(135deg, #ffffff 0%, var(--bg-tinted) 100%);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: 2.25rem;
  margin: 3rem 0;
  box-shadow: var(--shadow-md);
}

.widget-header {
  text-align: center;
  margin-bottom: 2rem;
}

.widget-header h3 {
  font-size: 1.45rem;
  color: var(--color-primary-deep);
  margin-bottom: 0.4rem;
}

.widget-header p {
  font-size: 0.9rem;
  color: var(--text-muted);
}

.widget-controls {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.25rem;
  margin-bottom: 1.75rem;
}

.control-group {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.control-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-primary-dark);
}

.control-group select,
.control-group input {
  padding: 0.65rem 0.9rem;
  border: 1px solid var(--border-light);
  border-radius: 8px;
  font-size: 0.95rem;
  background: #ffffff;
  color: var(--text-main);
  outline: none;
  transition: var(--transition-smooth);
}

.control-group select:focus,
.control-group input:focus {
  border-color: var(--color-primary-forest);
  box-shadow: 0 0 0 3px rgba(45, 106, 79, 0.12);
}

.widget-output {
  background: #ffffff;
  border-radius: var(--radius-md);
  padding: 1.5rem;
  border: 1px solid var(--border-light);
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  text-align: center;
}

.output-stat .val {
  font-family: var(--font-heading);
  font-size: 1.75rem;
  font-weight: 800;
  color: var(--color-primary-deep);
  line-height: 1.1;
}

.output-stat .lbl {
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-top: 0.3rem;
}

.widget-footer-action {
  text-align: center;
  margin-top: 1.5rem;
}

.btn-primary-action {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: linear-gradient(135deg, var(--color-primary-deep), var(--color-primary-forest));
  color: #ffffff;
  font-weight: 600;
  font-size: 0.95rem;
  padding: 0.85rem 1.8rem;
  border-radius: 50px;
  box-shadow: var(--shadow-sm);
  transition: var(--transition-smooth);
}

.btn-primary-action:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
  color: #ffffff;
}

/* --------------------------------------------------------------------------
   FAQ Accordion
   -------------------------------------------------------------------------- */
.faq-container {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin: 2rem 0;
}

.faq-item {
  background: var(--bg-card);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-sm);
  overflow: hidden;
  transition: var(--transition-smooth);
}

.faq-item summary {
  padding: 1.15rem 1.35rem;
  font-weight: 600;
  font-size: 1rem;
  color: var(--color-primary-dark);
  cursor: pointer;
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  user-select: none;
}

.faq-item summary::-webkit-details-marker {
  display: none;
}

.faq-item summary::after {
  content: '+';
  font-size: 1.3rem;
  font-weight: 400;
  color: var(--color-primary-forest);
  transition: transform 0.25s ease;
}

.faq-item[open] summary::after {
  transform: rotate(45deg);
}

.faq-answer {
  padding: 0 1.35rem 1.25rem;
  font-size: 0.93rem;
  color: var(--text-muted);
  line-height: 1.65;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  background: var(--color-primary-dark);
  color: #e2e8f0;
  padding: 4rem 1.5rem 2.5rem;
  font-size: 0.9rem;
  border-top: 3px solid var(--color-primary-forest);
}

.footer-container {
  max-width: 1160px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 3rem;
  padding-bottom: 2.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-col h5 {
  font-family: var(--font-heading);
  font-size: 1.05rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 1rem;
}

.footer-col p {
  color: #94a3b8;
  line-height: 1.6;
  font-size: 0.88rem;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-col ul a {
  color: #cbd5e1;
  font-size: 0.86rem;
}

.footer-col ul a:hover {
  color: var(--color-primary-mint);
}

.footer-bottom {
  max-width: 1160px;
  margin: 2rem auto 0;
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.8rem;
  color: #64748b;
  flex-wrap: wrap;
  gap: 1rem;
}

/* --------------------------------------------------------------------------
   Responsive Media Queries
   -------------------------------------------------------------------------- */
@media (max-width: 980px) {
  .article-layout {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  
  .toc-sidebar {
    display: none;
  }
  
  .hero-stats-grid {
    grid-template-columns: 1fr;
  }

  .widget-controls,
  .widget-output {
    grid-template-columns: 1fr;
  }

  .footer-container {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
}

@media (max-width: 640px) {
  .hero-title {
    font-size: 2rem;
  }

  .takeaway-grid {
    grid-template-columns: 1fr;
  }

  .nav-links {
    display: none;
  }
}