/* ============================================================
   DIFF VIEWER — Side-by-Side Code Review (v0.7)
   ============================================================ */

/* --- Overlay backdrop --- */
.diff-overlay {
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(10, 18, 30, 0.55);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  overflow: hidden;
  animation: fadeIn 0.2s ease;
}

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

/* --- Modal card --- */
.diff-modal {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: 0 24px 80px rgba(30, 58, 95, 0.22);
  width: 100%;
  max-width: 1320px;
  max-height: calc(100vh - 40px);
  display: flex;
  flex-direction: column;
  overflow: hidden;
  animation: fadeInUp 0.25s ease;
}

/* --- Modal header --- */
.diff-modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 24px;
  border-bottom: 1px solid var(--border);
  background: var(--surface-alt);
  flex-shrink: 0;
}

.diff-modal-title-group {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--navy);
}

.diff-modal-title-group svg {
  color: var(--green);
  flex-shrink: 0;
}

.diff-modal-title-group h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--navy);
  letter-spacing: -0.01em;
}

.diff-modal-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

/* Match count badge */
.diff-badge {
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 100px;
  background: rgba(76, 175, 80, 0.12);
  color: #2e7d32;
  border: 1px solid rgba(76, 175, 80, 0.25);
  white-space: nowrap;
}

/* Match navigation controls */
.diff-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.diff-nav.hidden { display: none; }

.diff-nav-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  padding: 0;
}
.diff-nav-btn:hover:not(:disabled) {
  background: rgba(30, 58, 95, 0.06);
  border-color: var(--border-hover);
  color: var(--navy);
}
.diff-nav-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.diff-nav-pos {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-secondary);
  min-width: 40px;
  text-align: center;
  white-space: nowrap;
}

/* Export buttons */
.diff-exports {
  display: flex;
  align-items: center;
  gap: 6px;
}
.diff-exports.hidden { display: none; }

.diff-export-btn {
  font-size: 11px;
  font-weight: 600;
  padding: 3px 9px;
  border-radius: var(--radius-xs);
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  text-decoration: none;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}
.diff-export-btn:hover {
  background: rgba(30, 58, 95, 0.06);
  border-color: var(--border-hover);
  color: var(--navy);
}

/* Close button */
.diff-close-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--border);
  border-radius: var(--radius-xs);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
}

.diff-close-btn:hover {
  background: rgba(30, 58, 95, 0.06);
  border-color: var(--border-hover);
  color: var(--navy);
}

/* --- State messages (loading / error / no-matches) --- */
.diff-state-msg {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 32px 24px;
  color: var(--text-secondary);
  font-size: 14px;
}

.diff-state-msg.hidden { display: none; }

.diff-error-msg { color: #b91c1c; }
.diff-info-msg  { color: var(--text-secondary); }

/* Mini spinner inside modal */
.diff-spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border);
  border-top-color: var(--green);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  flex-shrink: 0;
}

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

/* --- Diff panels container --- */
.diff-container {
  display: flex;
  gap: 0;
  min-height: 300px;
}

.diff-container.hidden { display: none; }

/* Vertical divider between the two panels */
.diff-gutter-divider {
  width: 1px;
  background: var(--border);
  flex-shrink: 0;
}

/* --- Individual panel --- */
.diff-panel {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.diff-panel-header {
  padding: 10px 16px;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  background: var(--bg-alt);
  border-bottom: 1px solid var(--border);
  letter-spacing: 0.02em;
  text-transform: uppercase;
  flex-shrink: 0;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* Scrollable code area */
.diff-code-wrap {
  overflow: auto;
  flex: 1;
  min-height: 120px;
  background: #13181f;
  font-family: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', Consolas, 'Courier New', monospace;
  font-size: 13px;
  line-height: 1.65;
}

/* Custom scrollbar for the code panels */
.diff-code-wrap::-webkit-scrollbar { width: 6px; height: 6px; }
.diff-code-wrap::-webkit-scrollbar-track { background: #1a2230; }
.diff-code-wrap::-webkit-scrollbar-thumb { background: #2e3f55; border-radius: 3px; }
.diff-code-wrap::-webkit-scrollbar-thumb:hover { background: #3d5470; }

/* --- Per-line rows --- */
.diff-line {
  display: flex;
  white-space: pre;
  min-height: 21.45px; /* 13px * 1.65 */
  transition: background 0.15s ease;
  min-width: 100%;
  width: fit-content;
}

.diff-line:hover {
  background: rgba(255, 255, 255, 0.03);
}

/* Matched / highlighted line */
.diff-line.matched {
  background: rgba(255, 193, 7, 0.11);
  border-left: 3px solid #f59e0b;
}

.diff-line.matched:hover {
  background: rgba(255, 193, 7, 0.16);
}

/* Line number gutter */
.line-num {
  color: #3d5470;
  width: 3.5em;
  min-width: 3.5em;
  text-align: right;
  padding: 0 10px 0 8px;
  user-select: none;
  flex-shrink: 0;
  border-right: 1px solid #1e2d3d;
}

.diff-line.matched .line-num {
  color: #c09020;
}

/* Code text */
.line-content {
  flex: 1;
  color: #cdd3de;
  padding: 0 12px;
  overflow: hidden;
  text-overflow: clip;
}


/* --- Responsive: stack panels vertically on small screens --- */
@media (max-width: 768px) {
  .diff-overlay {
    padding: 10px;
  }

  .diff-modal {
    max-height: calc(100vh - 20px);
  }

  .diff-modal-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
    padding: 12px 16px;
  }

  .diff-container {
    flex-direction: column;
  }

  .diff-gutter-divider {
    width: 100%;
    height: 1px;
  }

  .diff-code-wrap {
    min-height: 100px;
  }
}