/* ==========================================================================
   Thoughts - 我思我想 (Obsidian Knowledge Graph & Micro-Essays)
   Author: hilosi Kuo Website
   ========================================================================== */

:root {
  --bg-dark: #090d16;
  --bg-canvas: #0d1322;
  --bg-card: rgba(17, 24, 39, 0.75);
  --bg-card-hover: rgba(26, 36, 56, 0.9);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(56, 189, 248, 0.25);
  --border-active: #38bdf8;
  
  --purple-obsidian: #a855f7;
  --cyan-primary: #38bdf8;
  --cyan-bright: #64ffda;
  --blue-soft: #60a5fa;
  --amber-accent: #f59e0b;
  --emerald-accent: #10b981;
  
  --text-main: #f3f4f6;
  --text-muted: #9ca3af;
  --text-dim: #6b7280;

  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang TC", "Microsoft JhengHei", sans-serif;
  --font-serif: "Noto Serif TC", "Songti TC", Georgia, serif;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --shadow-card: 0 10px 30px -5px rgba(0, 0, 0, 0.6);
  --shadow-glow: 0 0 20px rgba(168, 85, 247, 0.2);
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-dark);
  background: radial-gradient(ellipse at 50% 0%, #151e36 0%, #0c1220 50%, var(--bg-dark) 100%);
  color: var(--text-main);
  line-height: 1.75;
  min-height: 100vh;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* ==========================================================================
   Header & Navbar
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  background: rgba(9, 13, 22, 0.85);
  border-bottom: 1px solid var(--border-subtle);
  transition: var(--transition);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-main);
  font-weight: 700;
  font-size: 1.15rem;
}

.nav-brand i {
  color: var(--purple-obsidian);
  font-size: 1.4rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 16px;
}

.nav-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  border-radius: var(--radius-full);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 500;
  transition: var(--transition);
}

.nav-btn:hover {
  background: rgba(168, 85, 247, 0.15);
  border-color: rgba(168, 85, 247, 0.4);
  color: #ffffff;
}

/* Language Switcher */
.lang-switcher {
  display: flex;
  align-items: center;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 2px;
  gap: 2px;
}

.lang-btn {
  padding: 4px 10px;
  border-radius: var(--radius-full);
  color: var(--text-dim);
  font-size: 0.8rem;
  font-weight: 600;
  text-decoration: none;
  transition: var(--transition);
}

.lang-btn:hover {
  color: #ffffff;
}

.lang-btn.active {
  background: var(--purple-obsidian);
  color: #ffffff;
  box-shadow: 0 1px 6px rgba(168, 85, 247, 0.4);
}

/* ==========================================================================
   Hero Intro
   ========================================================================== */
.hero-intro {
  padding: 40px 0 24px;
  text-align: center;
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 14px;
  border-radius: var(--radius-full);
  background: rgba(168, 85, 247, 0.12);
  border: 1px solid rgba(168, 85, 247, 0.3);
  color: #c084fc;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 2.6rem;
  font-weight: 800;
  letter-spacing: -0.5px;
  margin-bottom: 12px;
  background: linear-gradient(135deg, #ffffff 40%, #c084fc 80%, #38bdf8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-subtitle {
  font-size: 1.05rem;
  color: var(--text-muted);
  max-width: 680px;
  margin: 0 auto;
}

/* ==========================================================================
   Obsidian Graph Section
   ========================================================================== */
.graph-section {
  margin: 20px 0 36px;
  transition: var(--transition);
}

.graph-card {
  background: var(--bg-canvas);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  position: relative;
}

.graph-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 20px;
  background: rgba(13, 19, 34, 0.8);
  border-bottom: 1px solid var(--border-subtle);
}

.graph-status {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.88rem;
  color: var(--text-muted);
}

.graph-status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--purple-obsidian);
  box-shadow: 0 0 8px var(--purple-obsidian);
}

.graph-controls {
  display: flex;
  align-items: center;
  gap: 8px;
}

.graph-btn {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: var(--transition);
}

.graph-btn:hover {
  background: rgba(168, 85, 247, 0.2);
  color: #ffffff;
  border-color: var(--purple-obsidian);
}

.btn-toggle-graph {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: var(--radius-sm);
  background: rgba(168, 85, 247, 0.12);
  border: 1px solid rgba(168, 85, 247, 0.3);
  color: #d8b4fe;
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

.btn-toggle-graph:hover {
  background: rgba(168, 85, 247, 0.25);
  color: #ffffff;
}

.canvas-container {
  position: relative;
  width: 100%;
  height: 380px;
  background: radial-gradient(circle at center, #131b2e 0%, var(--bg-canvas) 85%);
  cursor: grab;
}

.canvas-container:active {
  cursor: grabbing;
}

#graphCanvas {
  width: 100%;
  height: 100%;
  display: block;
}

.graph-hint {
  position: absolute;
  bottom: 12px;
  left: 16px;
  font-size: 0.78rem;
  color: var(--text-dim);
  pointer-events: none;
  background: rgba(9, 13, 22, 0.6);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(255, 255, 255, 0.05);
}

/* Collapsed state */
.graph-section.collapsed .canvas-container {
  display: none;
}

/* ==========================================================================
   Filter Bar & Category Nav
   ========================================================================== */
.filter-wrapper {
  margin-bottom: 32px;
  position: sticky;
  top: 76px;
  z-index: 80;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(9, 13, 22, 0.85);
  padding: 14px 18px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.4);
}

.filter-top-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

/* Level 1 Category Pills */
.category-pills {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.cat-pill {
  padding: 6px 14px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text-muted);
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.cat-pill:hover {
  background: rgba(255, 255, 255, 0.08);
  color: #ffffff;
}

.cat-pill.active {
  background: linear-gradient(135deg, #7c3aed 0%, #a855f7 100%);
  border-color: #c084fc;
  color: #ffffff;
  box-shadow: 0 2px 10px rgba(168, 85, 247, 0.35);
}

.cat-count {
  font-size: 0.75rem;
  opacity: 0.8;
  background: rgba(0, 0, 0, 0.25);
  padding: 1px 6px;
  border-radius: var(--radius-full);
}

/* Search Bar */
.search-box {
  position: relative;
  min-width: 220px;
}

.search-box input {
  width: 100%;
  padding: 8px 14px 8px 36px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-subtle);
  background: rgba(17, 24, 39, 0.6);
  color: var(--text-main);
  font-size: 0.88rem;
  outline: none;
  transition: var(--transition);
}

.search-box input:focus {
  border-color: var(--purple-obsidian);
  box-shadow: 0 0 10px rgba(168, 85, 247, 0.2);
}

.search-box i {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-dim);
  font-size: 0.95rem;
}

/* Level 2 Subcategory Pills Row */
.subcat-pills-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  overflow-x: auto;
}

.subcat-label {
  font-size: 0.78rem;
  color: var(--text-dim);
  white-space: nowrap;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.subcat-pill {
  padding: 3px 10px;
  border-radius: var(--radius-sm);
  background: rgba(56, 189, 248, 0.06);
  border: 1px solid rgba(56, 189, 248, 0.15);
  color: var(--cyan-primary);
  font-size: 0.8rem;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.subcat-pill:hover {
  background: rgba(56, 189, 248, 0.18);
}

.subcat-pill.active {
  background: var(--cyan-primary);
  color: #040812;
  font-weight: 600;
}

/* ==========================================================================
   Micro-Essay Cards Wall (Grid / Masonry)
   ========================================================================== */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 28px;
  margin-bottom: 60px;
}

.thought-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-card);
  display: flex;
  flex-direction: column;
  transition: var(--transition);
  position: relative;
}

.thought-card:hover {
  background: var(--bg-card-hover);
  border-color: rgba(168, 85, 247, 0.4);
  transform: translateY(-4px);
  box-shadow: 0 15px 35px rgba(0, 0, 0, 0.6), var(--shadow-glow);
}

.thought-card.pulse-highlight {
  border-color: var(--cyan-bright);
  box-shadow: 0 0 30px rgba(100, 255, 218, 0.5);
  animation: pulseCard 1.5s ease-out;
}

@keyframes pulseCard {
  0% { transform: scale(1.02); }
  50% { transform: scale(1.01); }
  100% { transform: scale(1); }
}

/* Card Media */
.card-media-wrapper {
  position: relative;
  width: 100%;
  aspect-ratio: 16/9;
  overflow: hidden;
  background: #111827;
}

.card-media-wrapper img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  transition: transform 0.5s ease;
}

.thought-card:hover .card-media-wrapper img {
  transform: scale(1.05);
}

/* Category Badge on Image */
.card-category-badges {
  position: absolute;
  top: 12px;
  left: 12px;
  display: flex;
  gap: 6px;
}

.badge-l1 {
  background: rgba(168, 85, 247, 0.85);
  color: #ffffff;
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 600;
  backdrop-filter: blur(8px);
}

.badge-l2 {
  background: rgba(15, 23, 42, 0.85);
  color: var(--cyan-bright);
  border: 1px solid rgba(100, 255, 218, 0.3);
  padding: 3px 8px;
  border-radius: var(--radius-sm);
  font-size: 0.75rem;
  font-weight: 500;
  backdrop-filter: blur(8px);
}

/* Card Body Content */
.card-content {
  padding: 24px 24px 18px;
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card-title {
  font-size: 1.35rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 14px;
  line-height: 1.35;
}

.card-body-text {
  font-size: 0.96rem;
  color: #d1d5db;
  line-height: 1.85;
  margin-bottom: 20px;
  flex: 1;
  text-align: justify;
}

.card-body-text p {
  margin-bottom: 12px;
}

.card-body-text p:last-child {
  margin-bottom: 0;
}

/* Card Footer Meta */
.card-footer {
  padding-top: 14px;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--text-dim);
}

.card-meta-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.card-meta-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

.card-action-btn {
  background: transparent;
  border: none;
  color: var(--text-dim);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  font-size: 1rem;
  transition: var(--transition);
}

.card-action-btn:hover {
  color: var(--cyan-primary);
  background: rgba(255, 255, 255, 0.05);
}

/* No Results State */
.no-results {
  grid-column: 1 / -1;
  text-align: center;
  padding: 60px 20px;
  color: var(--text-dim);
}

.no-results i {
  font-size: 3rem;
  color: var(--purple-obsidian);
  margin-bottom: 12px;
  display: block;
}

/* Toast Message */
.toast-msg {
  position: fixed;
  bottom: 24px;
  right: 24px;
  background: rgba(168, 85, 247, 0.95);
  color: #ffffff;
  padding: 10px 18px;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  box-shadow: 0 6px 20px rgba(0, 0, 0, 0.5);
  z-index: 1000;
  opacity: 0;
  transform: translateY(10px);
  transition: var(--transition);
  pointer-events: none;
}

.toast-msg.show {
  opacity: 1;
  transform: translateY(0);
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
  border-top: 1px solid var(--border-subtle);
  background: rgba(9, 13, 22, 0.9);
  padding: 40px 0 30px;
  text-align: center;
}

.footer-nav {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.footer-nav a {
  color: var(--text-muted);
  text-decoration: none;
  font-size: 0.88rem;
  transition: var(--transition);
}

.footer-nav a:hover {
  color: var(--purple-obsidian);
}

.footer-quote {
  font-size: 0.9rem;
  color: var(--text-dim);
  font-style: italic;
  margin-bottom: 10px;
}

.footer-copy {
  font-size: 0.8rem;
  color: var(--text-dim);
}

/* Responsive */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2.1rem;
  }
  .cards-grid {
    grid-template-columns: 1fr;
  }
  .canvas-container {
    height: 300px;
  }
  .filter-wrapper {
    top: 68px;
    padding: 12px;
  }
}