@charset "UTF-8";
/**
 * ════════════════════════════════════════════════════
 * 🚀 ANTIGRAVITY LUMINOUS VARIANT SUDOKU FRAMEWORK 🚀
 * Ocean-Teal & Amber — Spectacle, Glass logic
 * ════════════════════════════════════════════════════
 */

:root {
  --site-primary:        #06b6d4;  /* Cyan/Teal */
  --site-primary-hover:  #0891b2;
  --site-primary-dark:   #0e7490;
  --site-primary-light:  #ecfeff;
  --site-primary-border: #a5f3fc;

  --site-accent:         #f59e0b;  /* Amber/Energy */
  --site-accent-hover:   #d97706;

  --site-secondary:      #8b5cf6;  /* Fuchsia/Violet fallback */
  
  --glass-bg: rgba(255, 255, 255, 0.65);
  --glass-blur: 24px;
  --glass-border: rgba(255, 255, 255, 0.4);
  --glass-border-dark: rgba(6, 182, 212, 0.2);

  --font-heading: 'Outfit', 'Inter', system-ui, sans-serif;
  --font-body: 'Outfit', 'Inter', system-ui, sans-serif;
  --font-number: 'SF Mono', 'Fira Code', 'Consolas', monospace;

  --container-max: 1200px;
  --radius-sm: 8px;
  --radius-card: 20px;
  
  --shadow-sm: 0 4px 12px rgba(6, 182, 212, 0.05);
  --shadow-md: 0 10px 30px rgba(6, 182, 212, 0.1);
  --shadow-hover: 0 16px 40px rgba(6, 182, 212, 0.2);
  --shadow-glass: inset 0 2px 2px rgba(255, 255, 255, 0.8), 0 8px 32px rgba(8, 145, 178, 0.15);
  --transition-smooth: cubic-bezier(0.16, 1, 0.3, 1);
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

html { scroll-behavior: smooth; }
body {
  /* Subtle glassy cyan background */
  background: #f8fafc;
  background-image: radial-gradient(circle at 15% 50%, rgba(6, 182, 212, 0.03) 0%, transparent 50%),
                    radial-gradient(circle at 85% 30%, rgba(245, 158, 11, 0.02) 0%, transparent 50%);
  background-attachment: fixed;
  color: #0f172a;
  font-family: var(--font-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

::selection {
  background: color-mix(in srgb, var(--site-primary) 25%, transparent);
  color: var(--site-primary-dark);
}

/* ════════════════════════════════════════════════════
   GLOBAL CONTAINER SYSTEM
   ════════════════════════════════════════════════════ */
.container {
  max-width: var(--container-max) !important;
  margin-left: auto !important;
  margin-right: auto !important;
  width: 100% !important;
  box-sizing: border-box !important;
}

@media (min-width: 1200px) {
  .container { padding-left: 20px !important; padding-right: 20px !important; }
}

main.antigravity-theme {
  display: flex;
  flex-direction: column;
  gap: 2.5rem;
  padding-bottom: 5rem;
}

/* ════════════════════════════════════════════════════
   LUMINOUS HEADER BRAND ZONE
   ════════════════════════════════════════════════════ */
.site-header {
  background: var(--glass-bg) !important;
  backdrop-filter: blur(var(--glass-blur)) !important;
  -webkit-backdrop-filter: blur(var(--glass-blur)) !important;
  border-bottom: 1px solid var(--glass-border) !important;
  box-shadow: 0 4px 30px rgba(6, 182, 212, 0.05) !important;
  padding-top: 1rem !important;
  padding-bottom: 1rem !important;
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  display: flex !important;
  align-items: center !important;
  gap: 0.75rem !important;
  text-decoration: none !important;
}

.logo img {
  filter: drop-shadow(0 4px 8px rgba(8, 145, 178, 0.2)) !important;
  width: 48px !important;
  height: 48px !important;
}

.logo .site-name {
  font-family: var(--font-heading) !important;
  font-size: 1.6rem !important;
  font-weight: 900 !important;
  color: var(--site-primary-dark) !important;
  letter-spacing: -0.02em !important;
  background: linear-gradient(135deg, var(--site-primary-dark), var(--site-primary));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  transition: opacity 0.3s ease !important;
}
.logo:hover .site-name { opacity: 0.8 !important; }

/* ════════════════════════════════════════════════════
   HERO: LUMINOUS VARIANT SHOWCASE
   ════════════════════════════════════════════════════ */
.hero-ag {
  position: relative;
  background: rgba(255, 255, 255, 0.5);
  backdrop-filter: blur(40px);
  -webkit-backdrop-filter: blur(40px);
  border-radius: 32px;
  border: 1px solid rgba(255, 255, 255, 0.8);
  box-shadow: var(--shadow-glass);
  margin-top: 2rem;
  overflow: hidden;
  padding: 5rem 3rem;
  display: flex;
  align-items: center;
}

.hero-ag-bg {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.glow-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.2;
}

.orb-1 {
  width: 500px; height: 500px;
  background: #22d3ee;
  top: -100px; right: -100px;
}

.orb-2 {
  width: 400px; height: 400px;
  background: #fbbf24;
  bottom: -50px; left: -50px;
}

.ag-grid-texture {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image: 
    linear-gradient(to right, rgba(6, 182, 212, 0.05) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(6, 182, 212, 0.05) 1px, transparent 1px);
  background-size: 60px 60px;
  mask-image: radial-gradient(circle at center, black 0%, transparent 80%);
  -webkit-mask-image: radial-gradient(circle at center, black 0%, transparent 80%);
}

.hero-ag-container {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: center;
}

.hero-ag-content {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.brand-eyebrow {
  display: inline-block;
  font-size: 0.85rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: #0284c7;
  background: rgba(14, 165, 233, 0.1);
  padding: 0.5rem 1.25rem;
  border-radius: 999px;
  border: 1px solid rgba(14, 165, 233, 0.3);
  box-shadow: inset 0 1px 2px rgba(255, 255, 255, 0.5);
  width: fit-content;
}

.hero-ag-title {
  font-size: 4rem;
  font-weight: 900;
  color: #0f172a;
  line-height: 1.1;
  letter-spacing: -0.04em;
  margin: 0;
}

.hero-ag-subtitle {
  font-size: 1.25rem;
  color: #334155;
  line-height: 1.6;
  margin: 0;
  font-weight: 500;
}

.hero-ag-stats {
  display: flex;
  gap: 1.25rem;
  margin-top: 1rem;
}

.hero-stat {
  background: rgba(255, 255, 255, 0.7);
  border: 1px solid rgba(255, 255, 255, 0.9);
  padding: 1.25rem;
  border-radius: 16px;
  box-shadow: 0 4px 20px rgba(6, 182, 212, 0.08);
  backdrop-filter: blur(10px);
  min-width: 100px;
}

.hero-stat .stat-number {
  display: block;
  font-size: 1.8rem;
  font-weight: 900;
  color: var(--site-primary-dark);
  font-family: var(--font-number);
  line-height: 1;
  margin-bottom: 0.25rem;
}

.hero-stat .stat-label {
  display: block;
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #64748b;
}

/* Futuristic Floating Boards */
.hero-ag-visual {
  position: relative;
  height: 400px;
  perspective: 1200px;
}

.floating-boards .glass-board {
  position: absolute;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.5);
  box-shadow: 0 20px 40px rgba(8, 145, 178, 0.15), inset 0 1px 1px rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transform-style: preserve-3d;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 12px;
}

.gb-bottom {
  width: 250px; height: 250px;
  bottom: 0; right: 10%;
  transform: rotateX(60deg) rotateZ(-30deg) translateZ(0);
  animation: hover-1 8s ease-in-out infinite;
}

.gb-middle {
  width: 200px; height: 200px;
  top: 15%; right: 25%;
  transform: rotateX(60deg) rotateZ(-30deg) translateZ(80px);
  animation: hover-2 6s ease-in-out infinite;
}

.gb-top {
  width: 100px; height: 100px;
  top: 0; right: 5%;
  background: rgba(245, 158, 11, 0.15) !important;
  border-color: rgba(245, 158, 11, 0.4) !important;
  transform: rotateX(60deg) rotateZ(-30deg) translateZ(160px);
  animation: hover-3 7s ease-in-out infinite;
}

.luminous-grid {
  width: 100%; height: 100%;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 4px;
}
.luminous-grid::before {
  content: ''; grid-area: 1/1/4/4;
  background-image: linear-gradient(rgba(255,255,255,0.4) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(255,255,255,0.4) 1px, transparent 1px);
  background-size: 33.33% 33.33%;
  border-radius: 8px;
}

.lg-amber::before {
  background-image: linear-gradient(rgba(245, 158, 11, 0.3) 1px, transparent 1px),
                    linear-gradient(90deg, rgba(245, 158, 11, 0.3) 1px, transparent 1px);
}

.variant-node {
  font-size: 3.5rem;
  font-weight: 900;
  color: var(--site-accent);
  text-shadow: 0 0 20px rgba(245, 158, 11, 0.6);
  transform: translateZ(20px);
}

@keyframes hover-1 { 0%, 100% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(0); } 50% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(10px); } }
@keyframes hover-2 { 0%, 100% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(80px); } 50% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(95px); } }
@keyframes hover-3 { 0%, 100% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(160px); } 50% { transform: rotateX(60deg) rotateZ(-30deg) translateZ(180px); } }

/* ════════════════════════════════════════════════════
   GLASS CALLOUTS (Editorial Notes)
   ════════════════════════════════════════════════════ */
.callout-glass {
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255, 255, 255, 0.9);
  padding: 2rem 2.5rem;
  border-radius: 20px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.callout-glass::before {
  content: '';
  position: absolute;
  top: 0; left: 0; bottom: 0;
  width: 6px;
  background: linear-gradient(180deg, var(--site-primary), var(--site-accent));
}

/* ════════════════════════════════════════════════════
   VARIANT CATEGORY SYSTEM (LUMINOUS MULTIVERSE)
   ════════════════════════════════════════════════════ */
.ag-section-header { margin-bottom: 2.5rem; text-align: center; }
.ag-section-title { font-size: 2.5rem; font-weight: 900; color: #0f172a; margin: 0 0 0.5rem; letter-spacing: -0.03em; }
.ag-section-subtitle { font-size: 1.15rem; color: #64748b; margin: 0; }

.ag-variant-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 2rem;
}

.ag-variant-card {
  display: flex;
  flex-direction: column;
  background: rgba(255, 255, 255, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.9);
  border-radius: 24px;
  padding: 2rem;
  text-decoration: none;
  transition: all 0.4s var(--transition-smooth);
  box-shadow: 0 4px 20px rgba(6, 182, 212, 0.04);
  position: relative;
  overflow: hidden;
  z-index: 1;
}

.ag-variant-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: radial-gradient(circle at top right, rgba(255,255,255,0.8), transparent);
  z-index: -1;
  opacity: 0;
  transition: opacity 0.4s ease;
}

.ag-variant-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-hover);
}

.ag-variant-card:hover::before { opacity: 1; }

/* Glow Colors */
.glow-cyan:hover { border-color: var(--site-primary-border); box-shadow: 0 16px 40px rgba(6, 182, 212, 0.2); }
.glow-cyan .variant-icon-plane { color: var(--site-primary); background: rgba(6, 182, 212, 0.1); border-color: rgba(6, 182, 212, 0.2); }

.glow-amber:hover { border-color: rgba(245, 158, 11, 0.3); box-shadow: 0 16px 40px rgba(245, 158, 11, 0.15); }
.glow-amber .variant-icon-plane { color: var(--site-accent); background: rgba(245, 158, 11, 0.1); border-color: rgba(245, 158, 11, 0.2); }

.glow-fuchsia:hover { border-color: rgba(217, 70, 239, 0.3); box-shadow: 0 16px 40px rgba(217, 70, 239, 0.15); }
.glow-fuchsia .variant-icon-plane { color: #d946ef; background: rgba(217, 70, 239, 0.1); border-color: rgba(217, 70, 239, 0.2); }

.glow-emerald:hover { border-color: rgba(16, 185, 129, 0.3); box-shadow: 0 16px 40px rgba(16, 185, 129, 0.15); }
.glow-emerald .variant-icon-plane { color: #10b981; background: rgba(16, 185, 129, 0.1); border-color: rgba(16, 185, 129, 0.2); }

.variant-icon-plane {
  width: 64px; height: 64px;
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin-bottom: 1.5rem;
  border: 1px solid transparent;
  transition: all 0.3s ease;
}

.v-icon { width: 32px; height: 32px; }

.ag-cat-titles { margin-bottom: 1.5rem; }
.ag-cat-title-link { font-size: 1.4rem; font-weight: 800; color: #0f172a; margin: 0 0 0.25rem; }
.ag-cat-desc { font-size: 0.95rem; color: #475569; margin: 0; }

.ag-cat-body {
  border-top: 1px solid rgba(0,0,0,0.04);
  padding-top: 1.5rem;
  margin-top: auto;
}

.ag-subcat-pills { display: flex; flex-wrap: wrap; gap: 0.5rem; align-items: center; }

.ag-subcat-pill {
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.4rem 0.8rem;
  border-radius: 8px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}
.pill-entry { background: rgba(6, 182, 212, 0.1); color: var(--site-primary-dark); }
.pill-adv { background: rgba(245, 158, 11, 0.1); color: #b45309; }
.pill-action { 
  background: transparent; color: #0f172a; border: 1px solid rgba(0,0,0,0.1);
  margin-left: auto; transition: all 0.2s ease;
}
.ag-variant-card:hover .pill-action {
  background: #0f172a; color: #fff; border-color: #0f172a;
}

/* ════════════════════════════════════════════════════
   GLASS EDITORIAL BREADCRUMB
   ════════════════════════════════════════════════════ */
.breadcrumb { margin: 0 0 1.5rem 0 !important; padding: 0 !important; }

.breadcrumb ol {
  display: flex !important; flex-wrap: wrap !important; align-items: center !important; gap: 0.5rem !important;
  list-style: none !important; padding: 0 !important; margin: 0 !important;
  font-family: var(--font-number) !important; font-size: 0.85rem !important; font-weight: 800 !important;
  text-transform: uppercase; letter-spacing: 0.05em;
}

.breadcrumb li { display: inline-flex; align-items: center; color: #94a3b8; }
.breadcrumb li:not(:last-child)::after {
  content: '>'; color: var(--glass-border-dark); margin-left: 0.5rem; font-size: 1rem;
}
.breadcrumb a { color: var(--site-primary-dark) !important; text-decoration: none !important; transition: all 0.2s ease !important; }
.breadcrumb a:hover { color: var(--site-accent) !important; text-shadow: 0 0 8px rgba(245, 158, 11, 0.3); }

/* ════════════════════════════════════════════════════
   PAGE HEADERS & SET SWITCHERS
   ════════════════════════════════════════════════════ */
.ag-page-header { margin-bottom: 2.5rem; }

.ag-set-switcher-wrapper {
  background: rgba(255, 255, 255, 0.6);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 1.5rem 2rem;
  margin: 2.5rem 0;
  display: flex; align-items: center; gap: 1.5rem;
  box-shadow: var(--shadow-sm);
}

.ag-set-switcher-label {
  font-weight: 900; font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.1em; color: #475569;
}
.ag-set-buttons { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.ag-set-btn { text-decoration: none; }
.ag-set-btn-inner {
  display: flex; align-items: center; justify-content: center;
  width: 44px; height: 44px;
  background: rgba(255, 255, 255, 0.9);
  color: #0f172a;
  border: 1px solid rgba(0,0,0,0.1);
  border-radius: 12px;
  font-weight: 800; font-family: var(--font-number);
  transition: all 0.3s var(--transition-smooth);
}
.ag-set-btn:hover .ag-set-btn-inner { background: var(--site-primary-light); border-color: var(--site-primary); transform: translateY(-3px); box-shadow: 0 4px 12px rgba(6, 182, 212, 0.2); color: var(--site-primary-dark); }
.ag-set-btn.active .ag-set-btn-inner { background: var(--site-primary); color: #fff; border-color: var(--site-primary); box-shadow: 0 6px 16px rgba(6, 182, 212, 0.3); }

/* ════════════════════════════════════════════════════
   HIGH-END PUZZLE BOARD ZONE
   ════════════════════════════════════════════════════ */
.board-glow-wrapper {
  position: relative;
  margin: 0 auto;
  /* Was 800px — too narrow for sidebar-board-hints layout (tools 200px + board 560px + hints 260px = 1020px).
     Let it fill the .detail-page container width (1200px). The solver-board's own max-width handles sizing. */
  max-width: 100%;
}

.board-ambient-glow {
  position: absolute;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%);
  width: 60%; height: 60%;
  background: radial-gradient(circle, rgba(6, 182, 212, 0.15) 0%, transparent 70%);
  filter: blur(40px);
  z-index: 0;
  pointer-events: none;
}

.ag-board-shell {
  position: relative;
  z-index: 1;
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  border: 1px solid rgba(255, 255, 255, 1);
  padding: 3.5rem;
  border-radius: 32px;
  box-shadow: var(--shadow-hover);
}

.da-toolbar {
  background: transparent !important;
  border: none !important;
  box-shadow: none !important;
  padding: 0 !important;
  margin-bottom: 2.5rem !important;
}

.da-board-grid {
  border: 3px solid rgba(15, 23, 42, 0.8) !important;
  border-radius: 4px !important;
  box-shadow: 0 10px 40px rgba(6, 182, 212, 0.15) !important;
  background: rgba(255,255,255,0.9) !important;
}

.da-sudoku-cell {
  font-family: var(--font-number) !important;
  font-weight: 800 !important;
  font-size: 1.5rem !important;
  transition: all 0.2s ease !important;
}

.da-sudoku-cell.given { color: #0f172a !important; font-weight: 900 !important; }
.da-sudoku-cell.user-input { color: var(--site-primary-dark) !important; }
/* Interaction glow */
.da-sudoku-cell.active-cell {
  background: rgba(6, 182, 212, 0.1) !important;
  box-shadow: inset 0 0 0 2px var(--site-primary) !important;
}


/* ════════════════════════════════════════════════════
   LUMINOUS PROSE & SEO CARDS
   ════════════════════════════════════════════════════ */
.ag-prose {
  font-family: var(--font-body);
  color: #334155;
  line-height: 1.8;
  max-width: 68ch;
  margin: 0 auto;
}

.ag-prose h2 { font-size: 1.8rem; font-weight: 900; color: #0f172a; margin: 2.5rem 0 1rem; letter-spacing: -0.02em; }
.ag-prose h3 { font-size: 1.4rem; font-weight: 800; color: var(--site-primary-dark); margin: 2rem 0 0.8rem; }
.ag-prose p { margin-bottom: 1.25rem; font-size: 1.1rem; }
.ag-prose a { color: var(--site-primary-dark); text-decoration: underline; text-underline-offset: 4px; font-weight: 700; }
.ag-prose a:hover { color: var(--site-accent); }
.ag-prose strong { color: #0f172a; font-weight: 900; }
.ag-prose ul { padding-left: 1.5rem; margin-bottom: 1.5rem; }
.ag-prose li { margin-bottom: 0.5rem; }
.ag-prose li::marker { color: var(--site-accent); }

.ag-seo-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
}

.ag-seo-card {
  background: rgba(255,255,255,0.7);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border: 1px solid rgba(255,255,255,0.9);
  padding: 2.5rem;
  border-radius: 24px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}

.ag-seo-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 4px;
  background: var(--site-primary);
}
.ag-seo-card.faq::before { background: var(--site-accent); }
.ag-seo-card.tips::before { background: var(--site-secondary); }

.ag-content-toggle summary {
  background: rgba(255,255,255,0.8);
  backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
  border: 1px solid var(--glass-border);
  padding: 1.5rem 2.5rem;
  border-radius: 16px;
  font-family: var(--font-heading);
  font-weight: 900;
  font-size: 1.25rem;
  cursor: pointer;
  color: #0f172a;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-sm);
  transition: all 0.3s ease;
}

.ag-content-toggle summary:hover { background: #ffffff; box-shadow: var(--shadow-md); color: var(--site-primary-dark); }

@media (max-width: 1024px) {
  .hero-ag-container { grid-template-columns: 1fr; text-align: center; }
  .hero-ag-visual { display: none; }
  .brand-eyebrow { margin: 0 auto; }
  .hero-ag-stats { justify-content: center; }
  .ag-section-header { text-align: center; }
  .ag-board-shell { padding: 1.5rem; border-radius: 20px; }
  .board-ambient-glow { width: 100%; height: 100%; }
}