/* PiltiSmart Academy Scientific Journal - Modern Academic Styling */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&family=Newsreader:ital,opsz,wght@0,6..72,400;0,6..72,500;0,6..72,600;0,6..72,700;1,6..72,400&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-serif: 'Newsreader', Georgia, 'Times New Roman', serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Color Palette - Light Mode */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-card: #ffffff;
  --bg-accent: #f1f5f9;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --brand-primary: #0f2744;
  --brand-accent: #2563eb;
  --brand-hover: #1d4ed8;
  --border-color: #e2e8f0;
  --border-light: #f1f5f9;
  --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
  --card-hover-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.04);
  
  --badge-pos-bg: #dcfce7;
  --badge-pos-text: #166534;
  --badge-neg-bg: #fee2e2;
  --badge-neg-text: #991b1b;
  --badge-neutral-bg: #e0f2fe;
  --badge-neutral-text: #075985;
}

[data-theme="dark"] {
  --bg-primary: #090d16;
  --bg-secondary: #0f172a;
  --bg-card: #131d33;
  --bg-accent: #1e293b;
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --brand-primary: #38bdf8;
  --brand-accent: #60a5fa;
  --brand-hover: #93c5fd;
  --border-color: #1e293b;
  --border-light: #334155;
  --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.3);
  --card-hover-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.4);

  --badge-pos-bg: #064e3b;
  --badge-pos-text: #6ee7b7;
  --badge-neg-bg: #7f1d1d;
  --badge-neg-text: #fca5a5;
  --badge-neutral-bg: #0c4a6e;
  --badge-neutral-text: #7dd3fc;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* Container */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.container-narrow {
  max-width: 860px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header & Nav */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.88);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
}
[data-theme="dark"] .site-header {
  background-color: rgba(9, 13, 22, 0.88);
}

.nav-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--text-primary);
}

.brand-icon {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, #0f2744 0%, #2563eb 100%);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 800;
  font-size: 20px;
}

.brand-text {
  display: flex;
  flex-direction: column;
}

.brand-title {
  font-weight: 800;
  font-size: 16px;
  letter-spacing: -0.3px;
  color: var(--text-primary);
}

.brand-subtitle {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-weight: 600;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 28px;
  list-style: none;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
}

.nav-link:hover, .nav-link.active {
  color: var(--brand-accent);
}

.theme-toggle-btn {
  background: var(--bg-accent);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 38px;
  height: 38px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
}

/* Hero Section */
.hero-section {
  padding: 64px 0 48px 0;
  background: radial-gradient(circle at top right, rgba(37, 99, 235, 0.06) 0%, transparent 60%);
  border-bottom: 1px solid var(--border-color);
}

.hero-tag {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background-color: var(--badge-neutral-bg);
  color: var(--badge-neutral-text);
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 16px;
}

.hero-title {
  font-size: 40px;
  font-weight: 800;
  letter-spacing: -1px;
  line-height: 1.15;
  margin-bottom: 16px;
  color: var(--text-primary);
}

.hero-desc {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 740px;
  line-height: 1.55;
  margin-bottom: 28px;
}

.hero-stats {
  display: flex;
  gap: 36px;
  padding-top: 16px;
  border-top: 1px solid var(--border-color);
}

.stat-item {
  display: flex;
  flex-direction: column;
}

.stat-number {
  font-size: 24px;
  font-weight: 800;
  color: var(--brand-accent);
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Filter & Search Bar */
.filter-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin: 40px 0 24px 0;
}

.category-tabs {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.tab-btn {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  color: var(--text-secondary);
  padding: 8px 16px;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
}

.tab-btn.active, .tab-btn:hover {
  background: var(--brand-primary);
  color: #fff;
  border-color: var(--brand-primary);
}

.search-input-wrapper {
  position: relative;
  min-width: 260px;
}

.search-input {
  width: 100%;
  padding: 8px 14px 8px 36px;
  border-radius: 20px;
  border: 1px solid var(--border-color);
  background: var(--bg-card);
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 14px;
}

/* Paper Cards Grid */
.papers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
  gap: 24px;
  margin-bottom: 64px;
}

.paper-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 28px;
  box-shadow: var(--card-shadow);
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.paper-card:hover {
  transform: translateY(-2px);
  box-shadow: var(--card-hover-shadow);
  border-color: var(--brand-accent);
}

.paper-card-header {
  margin-bottom: 16px;
}

.card-category {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--brand-accent);
  font-weight: 700;
  margin-bottom: 8px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.card-volume {
  color: var(--text-muted);
  font-size: 11px;
}

.card-title {
  font-size: 20px;
  font-weight: 700;
  line-height: 1.35;
  margin-bottom: 12px;
  color: var(--text-primary);
}

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

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

.card-authors {
  font-size: 13px;
  color: var(--text-secondary);
  font-weight: 500;
  margin-bottom: 14px;
}

.card-abstract {
  font-family: var(--font-serif);
  font-size: 14.5px;
  color: var(--text-secondary);
  line-height: 1.55;
  margin-bottom: 20px;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 16px;
  border-top: 1px solid var(--border-light);
}

.btn-primary {
  background: var(--brand-accent);
  color: #fff;
  padding: 8px 16px;
  border-radius: 6px;
  text-decoration: none;
  font-size: 13px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-primary:hover {
  background: var(--brand-hover);
}

.btn-secondary {
  background: var(--bg-accent);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  padding: 8px 14px;
  border-radius: 6px;
  text-decoration: none;
  font-size: 13px;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.btn-secondary:hover {
  background: var(--border-color);
}

/* Paper Reader View */
.reader-header {
  padding: 40px 0 24px 0;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 32px;
}

.reader-journal-tag {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  color: var(--brand-accent);
  font-weight: 700;
  margin-bottom: 12px;
}

.reader-title {
  font-family: var(--font-sans);
  font-size: 32px;
  font-weight: 800;
  line-height: 1.25;
  margin-bottom: 18px;
  color: var(--text-primary);
}

.reader-meta-box {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  align-items: center;
  font-size: 13px;
  color: var(--text-secondary);
  padding: 16px;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.meta-author {
  font-weight: 700;
  color: var(--text-primary);
}

/* Version Control UI */
.version-control-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 14px;
  padding: 10px 14px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 13px;
}

.version-label {
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 6px;
}

.version-select {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  padding: 6px 12px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  outline: none;
}

.version-select:focus {
  border-color: var(--brand-accent);
}

.version-archive-banner {
  background: #fef3c7;
  border: 1px solid #f59e0b;
  border-left: 5px solid #d97706;
  color: #92400e;
  padding: 14px 18px;
  border-radius: 8px;
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  font-size: 14px;
}

[data-theme="dark"] .version-archive-banner {
  background: rgba(245, 158, 11, 0.15);
  border-color: #d97706;
  color: #fde68a;
}

.version-archive-banner a {
  color: var(--brand-accent);
  font-weight: 700;
  text-decoration: underline;
}

.reader-actions {
  display: flex;
  gap: 12px;
  margin-top: 18px;
}

/* View Switcher Tabs */
.view-switcher {
  display: flex;
  gap: 4px;
  background: var(--bg-secondary);
  padding: 4px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  margin-bottom: 32px;
}

.view-tab-btn {
  flex: 1;
  padding: 10px 16px;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-weight: 600;
  font-size: 14px;
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
}

.view-tab-btn.active {
  background: var(--bg-card);
  color: var(--brand-accent);
  box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

/* Paper Content Typography */
.manuscript-body {
  font-family: var(--font-serif);
  font-size: 18px;
  line-height: 1.75;
  color: var(--text-primary);
}

.manuscript-body h2 {
  font-family: var(--font-sans);
  font-size: 22px;
  font-weight: 700;
  margin: 36px 0 16px 0;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-primary);
}

.manuscript-body h3 {
  font-family: var(--font-sans);
  font-size: 17px;
  font-weight: 600;
  color: var(--brand-accent);
  margin: 24px 0 12px 0;
}

.manuscript-body p {
  margin-bottom: 20px;
  text-align: justify;
}

.manuscript-body ul, .manuscript-body ol {
  margin: 0 0 20px 28px;
}

.manuscript-body li {
  margin-bottom: 8px;
}

/* Highlight Cards in Web Reader */
.web-highlight-card {
  border: 1px solid var(--border-color);
  border-left: 4px solid var(--brand-primary);
  background-color: var(--bg-secondary);
  padding: 16px 20px;
  border-radius: 6px;
  margin: 20px 0;
  font-family: var(--font-sans);
}

.web-highlight-card.success {
  border-left-color: #10b981;
}

.web-highlight-card.critical {
  border-left-color: #ef4444;
}

.web-highlight-card.experiment {
  border-left-color: #3b82f6;
}

.web-highlight-title {
  font-weight: 700;
  font-size: 15px;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.web-highlight-text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.55;
}

/* Debate Matrix View */
.debate-matrix-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 48px;
}

@media (max-width: 768px) {
  .debate-matrix-container {
    grid-template-columns: 1fr;
  }
}

.debate-column-header {
  padding: 14px 18px;
  border-radius: 8px 8px 0 0;
  font-weight: 700;
  font-size: 16px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.debate-column-header.pos {
  background-color: var(--badge-pos-bg);
  color: var(--badge-pos-text);
  border: 1px solid rgba(22, 101, 52, 0.2);
}

.debate-column-header.neg {
  background-color: var(--badge-neg-bg);
  color: var(--badge-neg-text);
  border: 1px solid rgba(153, 27, 27, 0.2);
}

.debate-card {
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  padding: 16px 18px;
  margin-bottom: 12px;
  border-radius: 8px;
  box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.debate-card-num {
  font-size: 11px;
  font-weight: 800;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-bottom: 4px;
}

.debate-card-title {
  font-size: 15px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.debate-card-desc {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.debate-card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--border-light);
}

.evidence-badge {
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 11px;
  font-weight: 700;
}

.evidence-badge.pos {
  background: var(--badge-pos-bg);
  color: var(--badge-pos-text);
}

.evidence-badge.neg {
  background: var(--badge-neg-bg);
  color: var(--badge-neg-text);
}

/* Footer */
.site-footer {
  background: var(--bg-secondary);
  border-top: 1px solid var(--border-color);
  padding: 48px 0 32px 0;
  margin-top: 64px;
  font-size: 13px;
  color: var(--text-secondary);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 32px;
  margin-bottom: 32px;
}

.footer-col {
  flex: 1;
  min-width: 220px;
}

.footer-title {
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 12px;
  font-size: 14px;
}

.footer-bottom {
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  color: var(--text-muted);
}