/* ============================
   Research Page Components
   ============================ */

/* Filter Bar */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.filter-btn {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 100px;
  padding: 7px 16px;
  font-family: var(--font-body);
  font-size: 13px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

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

.filter-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* Research Card (full) */
.research-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.research-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 0;
  transition: border-color var(--transition), box-shadow var(--transition);
  cursor: default;
}

.research-card:hover {
  border-color: var(--border-hover);
  box-shadow: 0 0 24px var(--accent-glow);
}

.research-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 16px;
}

.paper-info {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.research-card h3 {
  font-size: 15px;
  line-height: 1.4;
  letter-spacing: -0.01em;
  margin-bottom: 10px;
}

.research-card .abstract {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.65;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.paper-authors {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 16px;
  margin-bottom: 20px;
  flex-wrap: wrap;
}

.author-chip {
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-mono);
}

.author-chip::before {
  content: '—';
  margin-right: 4px;
  color: var(--text-muted);
}

.author-chip:first-child::before { display: none; }

.paper-date {
  font-size: 11px;
  font-family: var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.04em;
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.paper-btns {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 20px;
}

/* Citation popup */
.cite-popup {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
}

.cite-popup.open {
  opacity: 1;
  pointer-events: all;
}

.cite-box {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  max-width: 560px;
  width: calc(100% - 48px);
  position: relative;
}

.cite-box h4 {
  font-size: 14px;
  margin-bottom: 16px;
  font-family: var(--font-display);
}

.cite-code {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.7;
  color: var(--text-secondary);
  white-space: pre-wrap;
  word-break: break-all;
}

.cite-close {
  position: absolute;
  top: 16px;
  right: 16px;
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 20px;
  line-height: 1;
  transition: color var(--transition);
}

.cite-close:hover { color: var(--text-primary); }

/* Methodology Section */
.methodology {
  margin-top: 96px;
  padding-top: 96px;
  border-top: 1px solid var(--border);
}

.methodology-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--border);
  margin-top: 48px;
}

.method-step {
  background: var(--surface);
  padding: 32px 28px;
  transition: background var(--transition);
}

.method-step:hover { background: var(--surface-2); }

.step-number {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--accent);
  letter-spacing: 0.08em;
  margin-bottom: 16px;
  display: block;
}

.method-step h3 {
  font-size: 14px;
  margin-bottom: 10px;
}

.method-step p {
  font-size: 13px;
  line-height: 1.6;
}

/* ============================
   Tools Page Components
   ============================ */

/* Tools Grid */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.tool-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.tool-card:hover {
  border-color: var(--border-hover);
  box-shadow: 0 0 24px var(--accent-glow);
}

.tool-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.tool-icon {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.tool-icon svg {
  width: 18px;
  height: 18px;
  color: var(--accent);
}

.tool-title-row {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.tool-card h3 {
  font-size: 15px;
  letter-spacing: -0.01em;
}

.version-badge {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-muted);
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 100px;
  padding: 2px 8px;
  letter-spacing: 0.04em;
}

.tool-card p {
  font-size: 13px;
  line-height: 1.65;
}

/* npm install block */
.npm-block {
  display: flex;
  align-items: center;
  gap: 0;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 13px;
}

.npm-prompt {
  padding: 10px 14px;
  background: var(--surface-2);
  color: var(--text-muted);
  border-right: 1px solid var(--border);
  user-select: none;
  flex-shrink: 0;
}

.npm-cmd {
  padding: 10px 14px;
  color: var(--text-secondary);
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.npm-copy {
  padding: 10px 14px;
  background: none;
  border: none;
  border-left: 1px solid var(--border);
  color: var(--text-muted);
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
  font-family: var(--font-body);
  font-size: 12px;
  white-space: nowrap;
  flex-shrink: 0;
}

.npm-copy:hover {
  color: var(--accent);
  background: var(--accent-dim);
}

.npm-copy.copied {
  color: #34d399;
}

.npm-copy svg {
  width: 14px;
  height: 14px;
}

.tool-btns {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* REST API Teaser */
.api-section {
  margin-top: 96px;
  padding-top: 96px;
  border-top: 1px solid var(--border);
}

.api-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
}

.api-endpoints {
  display: flex;
  flex-direction: column;
  gap: 1px;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--border);
}

.endpoint-row {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 16px 20px;
  background: var(--surface);
  font-family: var(--font-mono);
  font-size: 13px;
  transition: background var(--transition);
}

.endpoint-row:hover { background: var(--surface-2); }

.method-tag {
  font-size: 11px;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.06em;
  min-width: 44px;
  text-align: center;
  flex-shrink: 0;
}

.method-get {
  background: rgba(52, 211, 153, 0.1);
  color: #34d399;
  border: 1px solid rgba(52, 211, 153, 0.2);
}

.method-post {
  background: rgba(96, 165, 250, 0.1);
  color: #60a5fa;
  border: 1px solid rgba(96, 165, 250, 0.2);
}

.endpoint-path {
  color: var(--text-secondary);
  flex: 1;
}

.endpoint-desc {
  font-size: 12px;
  color: var(--text-muted);
  font-family: var(--font-body);
}

/* Stack Integrations */
.stack-section {
  margin-top: 64px;
  padding: 48px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  text-align: center;
}

.stack-section h3 {
  margin-bottom: 8px;
  font-size: 18px;
}

.stack-section > p {
  font-size: 14px;
  margin-bottom: 32px;
}

.stack-badges {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  flex-wrap: wrap;
}

.stack-badge {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px 16px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  transition: all var(--transition);
}

.stack-badge:hover {
  border-color: var(--border-hover);
  color: var(--text-primary);
}

.stack-badge svg {
  width: 18px;
  height: 18px;
}

.stack-icon {
  width: 18px;
  height: 18px;
  border-radius: 4px;
  flex-shrink: 0;
}

/* ============================
   Toast Notification
   ============================ */
.toast {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 500;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 12px 20px;
  font-size: 13px;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 10px;
  transform: translateY(80px);
  opacity: 0;
  transition: all 0.3s ease;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

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

.toast svg {
  width: 16px;
  height: 16px;
  color: #34d399;
  flex-shrink: 0;
}

/* ============================
   Responsive Additions
   ============================ */
@media (max-width: 1024px) {
  .research-grid { grid-template-columns: 1fr; }
  .methodology-grid { grid-template-columns: repeat(2, 1fr); }
  .tools-grid { grid-template-columns: 1fr; }
  .api-inner { grid-template-columns: 1fr; gap: 40px; }
}

@media (max-width: 768px) {
  .methodology-grid { grid-template-columns: 1fr; }
  .stack-section { padding: 32px 20px; }
}