/* ==========================================================================
   Paper Graph Visualization — Styles
   Modern color scheme with gradients, light + dark modes
   ========================================================================== */

/* --- CSS Custom Properties (Theme Tokens) -------------------------------- */
:root {
  /* Tag colors (shared across themes) */
  --color-security: #4f6df5;
  --color-cyber: #e67e22;
  --color-general: #95a5a6;
}

[data-theme="dark"] {
  --bg-primary: #0f1117;
  --bg-surface: #1a1d2e;
  --bg-surface-hover: #242840;
  --bg-toolbar: linear-gradient(135deg, #141726 0%, #1e2240 100%);
  --bg-card: linear-gradient(160deg, #1a1d2e 0%, #232845 60%, #1a1d2e 100%);
  --bg-input: #232840;
  --border-color: #2d3154;
  --text-primary: #e8eaf0;
  --text-secondary: #9a9fc0;
  --text-muted: #6b70a0;
  --accent-gradient: linear-gradient(135deg, #6b8aff 0%, #a855f7 100%);
  --accent-solid: #6b8aff;
  --badge-security-bg: rgba(107, 138, 255, 0.15);
  --badge-security-text: #8da8ff;
  --badge-cyber-bg: rgba(245, 166, 35, 0.15);
  --badge-cyber-text: #f5a623;
  --badge-general-bg: rgba(127, 140, 141, 0.15);
  --badge-general-text: #a0aab0;
  --badge-project-bg: rgba(168, 85, 247, 0.15);
  --badge-project-text: #c084fc;
  --score-gradient: linear-gradient(90deg, #6b8aff 0%, #a855f7 100%);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.5);
  --overlay-bg: rgba(15, 17, 23, 0.85);
  --color-security: #6b8aff;
  --color-cyber: #f5a623;
  --color-general: #7f8c8d;
}

[data-theme="light"] {
  --bg-primary: #f5f6fa;
  --bg-surface: #ffffff;
  --bg-surface-hover: #f0f1f8;
  --bg-toolbar: linear-gradient(135deg, #ffffff 0%, #eef0f8 100%);
  --bg-card: linear-gradient(160deg, #ffffff 0%, #f5f0ff 60%, #ffffff 100%);
  --bg-input: #f0f1f8;
  --border-color: #d8dbe8;
  --text-primary: #1a1d2e;
  --text-secondary: #555a80;
  --text-muted: #8890b0;
  --accent-gradient: linear-gradient(135deg, #4f6df5 0%, #9333ea 100%);
  --accent-solid: #4f6df5;
  --badge-security-bg: rgba(79, 109, 245, 0.1);
  --badge-security-text: #4058d0;
  --badge-cyber-bg: rgba(230, 126, 34, 0.1);
  --badge-cyber-text: #c06010;
  --badge-general-bg: rgba(149, 165, 166, 0.1);
  --badge-general-text: #6b7280;
  --badge-project-bg: rgba(147, 51, 234, 0.1);
  --badge-project-text: #7c3aed;
  --score-gradient: linear-gradient(90deg, #4f6df5 0%, #9333ea 100%);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.1);
  --overlay-bg: rgba(245, 246, 250, 0.85);
  --color-security: #4f6df5;
  --color-cyber: #e67e22;
  --color-general: #95a5a6;
}

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

html, body {
  height: 100%;
  overflow: hidden;
  font-family: "Inter", "Segoe UI", system-ui, -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  transition: background 0.3s ease, color 0.3s ease;
}

/* --- Toolbar ------------------------------------------------------------- */
#toolbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  height: 56px;
  background: var(--bg-toolbar);
  border-bottom: 1px solid var(--border-color);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.toolbar-left, .toolbar-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.toolbar-logo {
  flex-shrink: 0;
}

.toolbar-title {
  font-size: 16px;
  font-weight: 700;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  white-space: nowrap;
}

/* Layer toggle */
.layer-toggle {
  display: flex;
  background: var(--bg-input);
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-color);
}

.layer-btn {
  padding: 6px 16px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.layer-btn.active {
  background: var(--accent-gradient);
  color: #fff;
  -webkit-text-fill-color: #fff;
}

.layer-btn:hover:not(.active) {
  background: var(--bg-surface-hover);
}

/* Search */
.search-box {
  position: relative;
  display: flex;
  align-items: center;
}

#search-input {
  width: 220px;
  padding: 7px 32px 7px 12px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-input);
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
  transition: border-color 0.2s ease;
}

#search-input::placeholder {
  color: var(--text-muted);
}

#search-input:focus {
  border-color: var(--accent-solid);
}

#search-clear {
  position: absolute;
  right: 4px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 16px;
  color: var(--text-muted);
  width: 24px;
  height: 24px;
  min-height: 0;
  border: none;
  padding: 0;
}

/* Help modal */
.help-overlay {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--overlay-bg);
  backdrop-filter: blur(4px);
  transition: opacity 0.2s ease;
}

.help-overlay.hidden {
  display: none;
}

.help-modal {
  position: relative;
  max-width: 480px;
  width: 90%;
  padding: 28px 28px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  box-shadow: var(--shadow-card);
}

.help-modal h2 {
  font-size: 18px;
  margin-bottom: 2px;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.help-subtitle {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.help-list {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 13px;
  line-height: 1.6;
  color: var(--text-secondary);
}

.help-list li {
  padding: 5px 0;
  border-top: 1px solid var(--border-color);
}

.help-list li:first-child {
  border-top: none;
}

.help-list strong {
  color: var(--text-primary);
}

.help-list em {
  color: var(--accent-solid);
  font-style: normal;
}

.help-close {
  position: absolute;
  top: 12px;
  right: 12px;
}

#help-toggle {
  font-weight: 700;
  font-size: 15px;
}

/* Icon buttons */
.icon-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--bg-input);
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 16px;
  transition: background 0.2s ease;
}

.icon-btn:hover {
  background: var(--bg-surface-hover);
}

/* Theme toggle icon visibility */
[data-theme="dark"] .theme-icon-dark { display: none; }
[data-theme="dark"] .theme-icon-light { display: inline; }
[data-theme="light"] .theme-icon-light { display: none; }
[data-theme="light"] .theme-icon-dark { display: inline; }

/* --- Legend --------------------------------------------------------------- */
#legend {
  position: fixed;
  bottom: 20px;
  left: 20px;
  z-index: 90;
  display: flex;
  gap: 14px;
  padding: 8px 16px;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  font-size: 12px;
  color: var(--text-secondary);
}

.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  user-select: none;
  transition: opacity 0.2s ease;
}

.legend-item:not(.active) {
  opacity: 0.35;
}

.legend-item:hover {
  opacity: 1;
}

.legend-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  display: inline-block;
}

/* --- View toggle --------------------------------------------------------- */
.view-toggle {
  display: flex;
  background: var(--bg-input);
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-color);
  margin-left: 4px;
}

.view-btn {
  padding: 6px 10px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 14px;
  cursor: pointer;
  transition: all 0.2s ease;
  line-height: 1;
}

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

.view-btn:hover:not(.active) {
  background: var(--bg-surface-hover);
}

/* --- Main split layout container ----------------------------------------- */
#main-container {
  position: fixed;
  top: 56px;
  left: 0;
  right: 0;
  bottom: 0;
  display: grid;
  grid-template-columns: 1fr;
  transition: grid-template-columns 0.3s ease;
}

#main-container.view-graph #paper-table-container {
  display: none;
}

#main-container.view-split {
  grid-template-columns: 1fr 1fr;
}

#main-container.view-list #graph-pane {
  display: none;
}

#main-container.view-list {
  grid-template-columns: 1fr;
}

/* --- Graph pane (contains hull, graph, label canvases) ------------------- */
#graph-pane {
  position: relative;
  overflow: hidden;
  min-width: 0;
}

#hull-canvas {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 0;
  pointer-events: none;
}

#label-canvas {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
  pointer-events: none;
}

#graph-container {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1;
}

/* --- Paper table pane ---------------------------------------------------- */
#paper-table-container {
  overflow-y: auto;
  overflow-x: hidden;
  border-left: 1px solid var(--border-color);
  background: var(--bg-primary);
  min-width: 0;
}

#paper-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  table-layout: fixed;
}

#paper-table thead {
  position: sticky;
  top: 0;
  z-index: 5;
  background: var(--bg-surface);
}

#paper-table th {
  padding: 10px 12px;
  text-align: left;
  font-weight: 600;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
  border-bottom: 2px solid var(--border-color);
  cursor: pointer;
  user-select: none;
  white-space: nowrap;
}

#paper-table th:hover {
  color: var(--text-primary);
}

.pt-col-title { width: auto; }
.pt-col-score { width: 70px; text-align: center; }
.pt-col-tag   { width: 90px; }
.pt-col-topic { width: 180px; }
.pt-col-date  { width: 100px; }

.sort-arrow {
  font-size: 10px;
  opacity: 0.6;
}

#paper-table td {
  padding: 8px 12px;
  border-bottom: 1px solid var(--border-color);
  vertical-align: middle;
}

#paper-table tbody tr {
  cursor: pointer;
  transition: background 0.15s ease;
}

#paper-table tbody tr:hover {
  background: var(--bg-surface-hover);
}

#paper-table tbody tr.pt-selected {
  background: var(--badge-security-bg);
}

#paper-table tbody tr.pt-hovered {
  background: var(--bg-surface-hover);
}

#paper-table tbody tr.pt-hidden {
  display: none;
}

.pt-cell-title {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-weight: 500;
  color: var(--text-primary);
}

.pt-cell-score {
  text-align: center;
  font-weight: 700;
  background: var(--score-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.pt-cell-tag {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}

.pt-cell-topic {
  font-size: 11px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  cursor: pointer;
}
.pt-cell-topic:hover {
  text-decoration: underline;
}

.pt-cell-date {
  color: var(--text-muted);
  font-size: 12px;
  white-space: nowrap;
}

/* --- Node hover tooltip -------------------------------------------------- */
.node-tooltip {
  position: fixed;
  z-index: 150;
  max-width: 320px;
  padding: 8px 12px;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  box-shadow: var(--shadow-card);
  font-size: 13px;
  font-weight: 600;
  line-height: 1.4;
  color: var(--text-primary);
  white-space: normal;
  word-wrap: break-word;
  overflow-wrap: break-word;
  pointer-events: none;
}

.node-tooltip.hidden {
  display: none;
}

/* --- Cluster filter banner ----------------------------------------------- */
.cluster-filter-banner {
  position: fixed;
  bottom: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 200;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--bg-surface);
  border: 2px solid var(--accent-solid);
  border-radius: 10px;
  box-shadow: var(--shadow-card);
  font-size: 14px;
  color: var(--text-primary);
  transition: opacity 0.2s ease;
}

.cluster-filter-banner.hidden {
  display: none;
}

.cluster-filter-banner .icon-btn {
  font-size: 18px;
  margin-left: 4px;
}

/* --- Selection ring (gradient halo around selected node) ----------------- */
.selection-ring {
  position: fixed;
  z-index: 140;
  pointer-events: none;
  border-radius: 50%;
  background: conic-gradient(from 0deg, #6b8aff, #a855f7, #ec4899, #6b8aff);
  animation: ring-spin 3s linear infinite;
}

.selection-ring::after {
  content: "";
  position: absolute;
  inset: 4px;
  border-radius: 50%;
  background: var(--bg-primary);
}

.selection-ring.hidden {
  display: none;
}

@keyframes ring-spin {
  to { transform: rotate(360deg); }
}

/* --- Card panel ---------------------------------------------------------- */
.card-panel {
  position: fixed;
  top: 56px;
  right: 0;
  bottom: 0;
  width: 400px;
  min-width: 280px;
  max-width: 80vw;
  z-index: 200;
  background: var(--bg-card);
  border-left: 1px solid var(--border-color);
  box-shadow: var(--shadow-card);
  overflow-y: auto;
  padding: 24px;
  padding-left: 30px;
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.card-panel.resizing {
  transition: none;
  user-select: none;
}

.card-resize-handle {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  width: 6px;
  cursor: col-resize;
  z-index: 210;
  background: transparent;
  transition: background 0.2s ease;
}

.card-resize-handle:hover,
.card-resize-handle.active {
  background: var(--accent-gradient);
}

.card-panel.hidden {
  transform: translateX(100%);
}

.card-close {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 10;
}

#card-title {
  font-size: 18px;
  font-weight: 700;
  line-height: 1.3;
  margin-bottom: 12px;
  padding-right: 36px;
}

#card-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

/* Badges */
.badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 600;
}

.score-badge {
  background: var(--score-gradient);
  color: #fff;
}

.tag-badge {
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.tag-security { background: var(--badge-security-bg); color: var(--badge-security-text); }
.tag-cyber    { background: var(--badge-cyber-bg);    color: var(--badge-cyber-text); }
.tag-general  { background: var(--badge-general-bg);  color: var(--badge-general-text); }

.cluster-badge {
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.3px;
}

.project-badge {
  background: var(--badge-project-bg);
  color: var(--badge-project-text);
  margin: 2px 4px 2px 0;
}

/* Card content */
.card-authors {
  font-size: 14px;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.card-affiliations {
  font-size: 13px;
  color: var(--text-secondary);
  font-style: italic;
  margin-bottom: 12px;
}

.card-link {
  display: inline-block;
  font-size: 13px;
  color: var(--accent-solid);
  text-decoration: none;
  font-weight: 600;
  margin-bottom: 14px;
  transition: opacity 0.2s ease;
}

.card-link:hover {
  opacity: 0.8;
}

.card-oneliner {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-primary);
  margin-bottom: 12px;
  padding: 12px;
  background: var(--bg-surface);
  border-radius: 8px;
  border-left: 3px solid var(--accent-solid);
}

.card-points {
  list-style: none;
  margin-bottom: 14px;
}

.card-points li {
  position: relative;
  padding: 6px 0 6px 18px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--text-secondary);
}

.card-points li::before {
  content: "→";
  position: absolute;
  left: 0;
  color: var(--accent-solid);
  font-weight: 700;
}

.card-projects {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-top: 8px;
}

/* Linked papers section */
.card-linked {
  margin-top: 16px;
  border-top: 1px solid var(--border-color);
  padding-top: 12px;
}

.card-linked:empty {
  display: none;
}

.card-linked-heading {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-secondary);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.card-linked-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.card-linked-list li {
  padding: 4px 0;
}

.card-linked-item {
  font-size: 13px;
  color: var(--accent-solid);
  text-decoration: none;
  line-height: 1.4;
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  transition: opacity 0.2s ease;
}

.card-linked-item:hover {
  opacity: 0.7;
}

.card-similarity-score {
  font-size: 11px;
  color: var(--text-muted);
  opacity: 0.8;
}

#card-date {
  font-size: 12px;
  color: var(--text-muted);
}

/* --- Loading overlay ----------------------------------------------------- */
#loading-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  background: var(--overlay-bg);
  backdrop-filter: blur(8px);
  gap: 16px;
  font-size: 14px;
  color: var(--text-secondary);
}

.spinner {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent-solid);
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

/* --- Responsive: mobile -------------------------------------------------- */
@media (max-width: 768px) {
  #toolbar {
    padding: 0 12px;
    height: 48px;
    flex-wrap: wrap;
  }
  .toolbar-title { font-size: 14px; }
  .layer-btn { padding: 5px 10px; font-size: 12px; }
  #search-input { width: 140px; font-size: 12px; }

  .card-panel {
    top: auto;
    bottom: 0;
    left: 0;
    right: 0;
    width: 100%;
    max-width: 100%;
    height: 60vh;
    max-height: 60vh;
    border-left: none;
    border-top: 1px solid var(--border-color);
    border-radius: 16px 16px 0 0;
  }

  .card-panel.hidden {
    transform: translateY(100%);
  }

  #main-container {
    top: 48px;
  }

  /* Force graph-only or list-only on mobile — no split */
  #main-container.view-split {
    grid-template-columns: 1fr;
  }
  #main-container.view-split #paper-table-container {
    display: none;
  }
}