/* ============================================================
   AI Fuse — Style Sheet
   Linear-inspired dark cyberpunk theme
   ============================================================ */

/* --- CSS Variables --- */
:root {
  --bg-primary: #08090a;
  --bg-panel: #0f1011;
  --bg-surface: #191a1b;
  --bg-card: rgba(255,255,255,0.02);
  --bg-card-hover: rgba(255,255,255,0.05);
  --text-primary: #f7f8f8;
  --text-secondary: #8a8f98;
  --text-muted: #62666d;
  --accent-cyan: #00d4ff;
  --accent-cyan-glow: rgba(0,212,255,0.3);
  --accent-magenta: #ff0080;
  --accent-magenta-dim: rgba(255,0,128,0.15);
  --border-subtle: rgba(255,255,255,0.05);
  --border-standard: rgba(255,255,255,0.08);
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --font-sans: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
  --max-width: 1200px;
  --header-height: 64px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
button { border: none; background: none; cursor: pointer; font-family: inherit; color: inherit; }
input { font-family: inherit; color: inherit; }

/* --- Scrollbar --- */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-primary); }
::-webkit-scrollbar-thumb { background: var(--text-muted); border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }

/* --- Background Gradient Animation --- */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 50% -20%, rgba(0,212,255,0.06) 0%, transparent 60%),
              radial-gradient(ellipse 60% 50% at 80% 80%, rgba(255,0,128,0.04) 0%, transparent 50%),
              radial-gradient(ellipse 50% 40% at 20% 60%, rgba(0,212,255,0.03) 0%, transparent 50%);
  pointer-events: none;
  z-index: 0;
  animation: bgShift 20s ease-in-out infinite alternate;
}

@keyframes bgShift {
  0% { opacity: 0.6; }
  50% { opacity: 1; }
  100% { opacity: 0.6; }
}

/* --- Particle Canvas --- */
#particle-canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 1;
  pointer-events: none;
}

/* --- Shared Container --- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 2;
}

/* ============================================================
   HEADER
   ============================================================ */
.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--header-height);
  z-index: 100;
  background: rgba(8,9,10,0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition);
}

.header.scrolled {
  background: rgba(8,9,10,0.95);
  border-bottom-color: var(--border-standard);
}

.header .container {
  display: flex;
  align-items: center;
  height: 100%;
  gap: 24px;
}

.logo {
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -0.5px;
  white-space: nowrap;
  color: var(--text-primary);
}

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

/* Language Toggle */
.lang-toggle {
  display: flex;
  background: var(--bg-panel);
  border: 1px solid var(--border-standard);
  border-radius: var(--radius-sm);
  overflow: hidden;
  flex-shrink: 0;
}

.lang-btn {
  padding: 4px 10px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-muted);
  transition: var(--transition);
}

.lang-btn.active {
  color: var(--accent-cyan);
  background: rgba(0,212,255,0.1);
}

/* Search */
.search-wrapper {
  flex: 1;
  max-width: 320px;
  position: relative;
}

.search-input {
  width: 100%;
  padding: 8px 12px 8px 36px;
  background: var(--bg-panel);
  border: 1px solid var(--border-standard);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  color: var(--text-primary);
  outline: none;
  transition: var(--transition);
}

.search-input::placeholder { color: var(--text-muted); }
.search-input:focus {
  border-color: var(--accent-cyan);
  box-shadow: 0 0 0 3px var(--accent-cyan-glow);
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 16px;
  height: 16px;
  color: var(--text-muted);
  pointer-events: none;
}

/* Search shortcut hint */
.search-hint {
  display: none;
  position: absolute;
  right: 10px;
  top: 50%;
  transform: translateY(-50%);
  padding: 1px 6px;
  font-size: 0.6875rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: 3px;
}

@media (min-width: 768px) {
  .search-hint { display: block; }
}

/* ============================================================
   HERO
   ============================================================ */
.hero {
  min-height: 70vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 120px 24px 80px;
  position: relative;
  z-index: 2;
}

.hero-content {
  max-width: 800px;
}

.hero h1 {
  font-size: clamp(2rem, 5vw, 3.5rem);
  font-weight: 600;
  letter-spacing: -1.5px;
  line-height: 1.1;
  margin-bottom: 16px;
  text-shadow: 0 0 40px rgba(0,212,255,0.15), 0 0 80px rgba(0,212,255,0.05);
}

.hero h1 .highlight {
  background: linear-gradient(135deg, var(--accent-cyan), var(--accent-magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-sub {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  margin-bottom: 32px;
  line-height: 1.6;
}

.typed-text {
  color: var(--accent-cyan);
}

.typed-cursor {
  display: inline-block;
  width: 2px;
  height: 1.2em;
  background: var(--accent-cyan);
  margin-left: 2px;
  vertical-align: text-bottom;
  animation: blink 1s step-end infinite;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 28px;
  background: linear-gradient(135deg, var(--accent-cyan), #0099cc);
  color: #000;
  font-weight: 600;
  font-size: 1rem;
  border-radius: var(--radius-md);
  transition: var(--transition);
  box-shadow: 0 0 20px var(--accent-cyan-glow);
}

.hero-cta:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--accent-cyan-glow);
}

/* ============================================================
   TAB NAVIGATION
   ============================================================ */
.tab-nav {
  display: flex;
  gap: 4px;
  padding: 4px;
  background: var(--bg-panel);
  border: 1px solid var(--border-standard);
  border-radius: var(--radius-lg);
  margin-bottom: 40px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.tab-btn {
  padding: 10px 20px;
  font-size: 0.9375rem;
  font-weight: 500;
  color: var(--text-muted);
  border-radius: var(--radius-sm);
  transition: var(--transition);
  white-space: nowrap;
  flex-shrink: 0;
}

.tab-btn:hover { color: var(--text-secondary); }

.tab-btn.active {
  color: var(--accent-cyan);
  background: rgba(0,212,255,0.08);
}

/* ============================================================
   FILTER TAGS
   ============================================================ */
.filter-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 32px;
}

.filter-tag {
  padding: 4px 14px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  background: transparent;
  border: 1px solid var(--border-standard);
  border-radius: 999px;
  transition: var(--transition);
}

.filter-tag:hover {
  border-color: var(--text-muted);
  color: var(--text-primary);
}

.filter-tag.active {
  background: var(--accent-magenta-dim);
  border-color: var(--accent-magenta);
  color: var(--accent-magenta);
}

/* ============================================================
   CARD GRID
   ============================================================ */
.card-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  margin-bottom: 40px;
}

@media (min-width: 768px) {
  .card-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
  .card-grid { grid-template-columns: repeat(3, 1fr); }
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border-standard);
  border-radius: var(--radius-md);
  padding: 24px;
  transition: var(--transition);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: var(--radius-md);
  opacity: 0;
  transition: var(--transition);
  background: linear-gradient(135deg, rgba(0,212,255,0.03), rgba(255,0,128,0.03));
}

.card:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
  box-shadow: 0 0 20px rgba(0,212,255,0.08);
}

.card:hover::before { opacity: 1; }

.card-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  position: relative;
  z-index: 1;
}

.card-icon {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.25rem;
  background: var(--bg-surface);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  flex-shrink: 0;
}

.card-title {
  font-size: 1.0625rem;
  font-weight: 600;
  letter-spacing: -0.3px;
  color: var(--text-primary);
}

.card-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 16px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
  position: relative;
  z-index: 1;
}

.card-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-bottom: 16px;
  position: relative;
  z-index: 1;
}

.card-tag {
  padding: 2px 10px;
  font-size: 0.75rem;
  font-weight: 500;
  background: var(--accent-magenta-dim);
  color: var(--accent-magenta);
  border-radius: 999px;
}

.card-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent-cyan);
  position: relative;
  z-index: 2;
  transition: var(--transition);
}

.card-link:hover { gap: 10px; }

/* ============================================================
   SEARCH HIGHLIGHT
   ============================================================ */
.search-highlight {
  background: rgba(0,212,255,0.2);
  color: var(--accent-cyan);
  padding: 0 2px;
  border-radius: 2px;
}

/* ============================================================
   EMPTY STATE
   ============================================================ */
.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 60px 24px;
  color: var(--text-muted);
}

.empty-state .empty-icon {
  font-size: 3rem;
  margin-bottom: 16px;
}

.empty-state p {
  font-size: 1rem;
}

/* ============================================================
   NEWS TIMELINE
   ============================================================ */
.news-section {
  display: none;
}

.news-section.active {
  display: block;
}

.news-timeline {
  position: relative;
  padding-left: 32px;
}

.news-timeline::before {
  content: '';
  position: absolute;
  left: 7px;
  top: 0;
  bottom: 0;
  width: 2px;
  background: var(--border-standard);
}

.news-item {
  position: relative;
  padding-bottom: 32px;
}

.news-item:last-child { padding-bottom: 0; }

.news-dot {
  position: absolute;
  left: -28px;
  top: 4px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--bg-surface);
  border: 2px solid var(--accent-cyan);
  display: flex;
  align-items: center;
  justify-content: center;
}

.news-dot::after {
  content: '';
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent-cyan);
}

.news-date {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--accent-cyan);
  margin-bottom: 4px;
}

.news-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.news-desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}

.news-item a {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-top: 8px;
  font-size: 0.8125rem;
  color: var(--accent-cyan);
  transition: var(--transition);
}

.news-item a:hover { gap: 8px; }

/* ============================================================
   SCROLL ANIMATIONS
   ============================================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in-scale {
  opacity: 0;
  transform: scale(0.95);
  transition: opacity 0.5s ease, transform 0.5s ease;
}

.fade-in-scale.visible {
  opacity: 1;
  transform: scale(1);
}

/* ============================================================
   MAIN CONTENT
   ============================================================ */
.main-content {
  padding-bottom: 80px;
  position: relative;
  z-index: 2;
}

.section {
  display: none;
}

.section.active {
  display: block;
}

/* ============================================================
   FOOTER
   ============================================================ */
.footer {
  border-top: 1px solid var(--border-subtle);
  padding: 32px 24px;
  text-align: center;
  position: relative;
  z-index: 2;
}

.footer p {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

/* ============================================================
   RESPONSIVE
   ============================================================ */
/* ============================================================
   DETAIL MODAL
   ============================================================ */
#modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(8px);
  z-index: 200;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}
#modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal {
  position: fixed;
  top: 50%; left: 50%;
  transform: translate(-50%, -50%) scale(0.9);
  width: 90%;
  max-width: 640px;
  max-height: 85vh;
  z-index: 201;
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  overflow-y: auto;
}
.modal.open {
  opacity: 1;
  pointer-events: auto;
  transform: translate(-50%, -50%) scale(1);
}

.modal-content {
  background: var(--bg-surface);
  border: 1px solid var(--border-standard);
  border-radius: var(--radius-lg);
  padding: 32px;
  position: relative;
  box-shadow: 0 0 40px rgba(0,212,255,0.1);
}

.modal-close {
  position: absolute;
  top: 16px; right: 16px;
  width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem;
  color: var(--text-muted);
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: 50%;
  transition: var(--transition);
}
.modal-close:hover { color: var(--text-primary); border-color: var(--text-muted); }

.modal-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 16px;
}
.modal-icon {
  width: 48px; height: 48px;
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem;
  background: var(--bg-panel);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
  flex-shrink: 0;
}
.modal-title {
  font-size: 1.375rem;
  font-weight: 600;
  letter-spacing: -0.5px;
  color: var(--text-primary);
}
.modal-short {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-top: 2px;
}

.modal-tags { margin-bottom: 16px; }
.modal-tags .card-tag { font-size: 0.75rem; }

.modal-desc {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 24px;
}

.modal-section { margin-bottom: 24px; }
.modal-section h3 {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--accent-cyan);
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-subtle);
}

.feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.feature-list li {
  position: relative;
  padding-left: 20px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.5;
}
.feature-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-cyan);
  opacity: 0.5;
}

.version-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.version-item {
  display: grid;
  grid-template-columns: auto auto 1fr;
  gap: 12px;
  align-items: baseline;
  padding: 8px 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
}
.version-badge {
  font-size: 0.75rem;
  font-weight: 600;
  font-family: var(--font-mono);
  color: var(--accent-cyan);
  background: rgba(0,212,255,0.1);
  padding: 2px 8px;
  border-radius: 4px;
  white-space: nowrap;
}
.version-date {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  white-space: nowrap;
}
.version-desc {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.modal-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  background: linear-gradient(135deg, var(--accent-cyan), #0099cc);
  color: #000;
  font-weight: 600;
  font-size: 0.875rem;
  border-radius: var(--radius-sm);
  transition: var(--transition);
  margin-top: 8px;
}
.modal-link:hover { gap: 10px; }

/* Card rank badge */
.card-rank {
  font-size: 0.75rem;
  font-weight: 600;
  font-family: var(--font-mono);
  color: var(--accent-magenta);
  background: var(--accent-magenta-dim);
  padding: 2px 8px;
  border-radius: 4px;
  margin-left: auto;
}

/* Card meta (feature/version count) */
.card-meta {
  display: flex;
  gap: 12px;
  margin-top: 8px;
  position: relative;
  z-index: 1;
}
.card-meta-item {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 3px;
}

@media (max-width: 768px) {
  .header .container { gap: 12px; }
  
  .search-wrapper { max-width: none; }
  
  .tab-nav { 
    border-radius: var(--radius-md);
    margin-bottom: 24px;
  }
  
  .tab-btn { padding: 8px 14px; font-size: 0.875rem; }
  
  .hero { min-height: 60vh; padding: 100px 16px 60px; }
  
  .card { padding: 16px; }
  
  .lang-btn { padding: 4px 8px; font-size: 0.75rem; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.75rem; }
  .hero-sub { font-size: 0.9375rem; }
}