:root {
  --mono:
    ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono",
    "Courier New", monospace;
  --sans:
    ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial,
    "Apple Color Emoji", "Segoe UI Emoji";
}

/* =========================
   THEME VARIABLES
   ========================= */

/* Default = dark */
:root {
  --bg: #0b0f17;
  --panel: #101827;
  --border: #1d2a44;
  --text: #e6edf7;
  --muted: #9fb0c8;
  --btn: #1b2a46;
  --btnHover: #24365a;

  --topbarBg: rgba(16, 24, 39, 0.92);
  --hoverBg: rgba(230, 237, 247, 0.08);
  --treeDash: rgba(159, 176, 200, 0.35);

  --shadow: 0 8px 24px rgba(0, 0, 0, 0.22);
  --shadowSoft: 0 2px 10px rgba(0, 0, 0, 0.18);
  --focus: 0 0 0 3px rgba(106, 166, 255, 0.28);
  --accent: #6aa6ff;
}

/* Light theme */
:root[data-theme="light"] {
  --bg: #f6f8fc;
  --panel: #ffffff;
  --border: #d7deea;
  --text: #0e1625;
  --muted: #52627a;
  --btn: #eef2fb;
  --btnHover: #e3e9f7;

  --topbarBg: rgba(255, 255, 255, 0.92);
  --hoverBg: rgba(14, 22, 37, 0.06);
  --treeDash: rgba(82, 98, 122, 0.35);

  --shadow: 0 10px 26px rgba(14, 22, 37, 0.1);
  --shadowSoft: 0 2px 10px rgba(14, 22, 37, 0.08);
  --focus: 0 0 0 3px rgba(66, 127, 255, 0.22);
  --accent: #2f6fff;
}

/* Explicit dark */
:root[data-theme="dark"] {
  --bg: #0b0f17;
  --panel: #101827;
  --border: #1d2a44;
  --text: #e6edf7;
  --muted: #9fb0c8;
  --btn: #1b2a46;
  --btnHover: #24365a;

  --topbarBg: rgba(16, 24, 39, 0.92);
  --hoverBg: rgba(230, 237, 247, 0.08);
  --treeDash: rgba(159, 176, 200, 0.35);

  --shadow: 0 8px 24px rgba(0, 0, 0, 0.22);
  --shadowSoft: 0 2px 10px rgba(0, 0, 0, 0.18);
  --focus: 0 0 0 3px rgba(106, 166, 255, 0.28);
  --accent: #6aa6ff;
}

/* =========================
   BASE LAYOUT
   ========================= */

* {
  box-sizing: border-box;
}

html {
  min-height: 100%;
}

body {
  min-height: 100vh;
}

body {
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  display: flex;
  flex-direction: column;
}

main.layout {
  flex: 1 1 auto;
  min-height: 0;
}

/* =========================
   HEADER
   ========================= */

.topbar {
  display: flex;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--topbarBg);
  position: sticky;
  top: 0;
  z-index: 10;
  box-shadow: 0 1px 0 rgba(255, 255, 255, 0.04);
}

@supports (backdrop-filter: blur(6px)) {
  .topbar {
    backdrop-filter: blur(6px);
  }
}

.title .h1 {
  font-weight: 700;
  font-size: 16px;
}

.title .sub {
  color: var(--muted);
  font-size: 12px;
  margin-top: 2px;
}

.title {
  margin-right: auto; /* pushes everything else to the right */
}

.actions {
  display: flex;
  align-items: center;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.actions .group {
  display: flex;
  align-items: center;
  gap: 8px;
  padding-left: 12px;
  border-left: 1px solid var(--border);
}

.actions .group:first-child {
  border-left: none;
  padding-left: 0;
}

.group.settings {
  gap: 16px; /* base spacing */
  opacity: 0.9;
}

.group.settings select {
  margin-left: 10px; /* extra separation from checkboxes */
  font-size: 12px;
}

.check {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--muted);
  cursor: pointer;
  user-select: none;
}

/* Hide default checkbox */
.check input {
  appearance: none;
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--panel);
  display: inline-grid;
  place-content: center;
}

/* Checked state */
.check input:checked {
  background: var(--btnHover);
  border-color: var(--btnHover);
}

/* Checkmark */
.check input:checked::after {
  content: "";
  width: 6px;
  height: 6px;
  background: var(--text);
  border-radius: 2px;
}

/* Hover */
.check:hover input {
  border-color: var(--muted);
}

.actions input[type="text"],
.actions input:not([type]) {
  width: 140px;
  padding: 7px 8px;
  font-size: 12px;
  border-radius: 6px;
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
}

.actions input::placeholder {
  color: var(--muted);
}

.actions button {
  font-size: 12px;
  padding: 7px 10px;
}

.group.export button {
  font-weight: 600;
}

.group.export button:first-child {
  opacity: 0.85;
}

.group.export button:last-child {
  background: var(--btnHover);
}

@media (max-width: 900px) {
  .actions {
    justify-content: flex-end;
  }

  .actions .group {
    border-left: none;
    padding-left: 0;
  }
}

/* =========================
   CONTROLS
   ========================= */

button,
.fileBtn,
select {
  cursor: pointer;
  border: 1px solid var(--border);
  background: var(--btn);
  color: var(--text);
  padding: 8px 10px;
  border-radius: 8px;
  font-size: 13px;
  transition:
    background 120ms ease,
    transform 80ms ease;
  outline: none;
}

button:hover,
.fileBtn:hover,
select:hover {
  background: var(--btnHover);
}

button:active,
.fileBtn:active,
select:active {
  transform: translateY(1px);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

button:focus-visible,
.fileBtn:focus-visible,
select:focus-visible {
  box-shadow: var(--focus);
  border-color: var(--accent);
}

select {
  padding-right: 28px;
}

.sep {
  width: 1px;
  height: 26px;
  background: var(--border);
  margin: 0 2px;
}

.sep.break {
  display: block;
  width: 100%;
  height: 0;
}

.check {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--muted);
  font-size: 12px;
  user-select: none;
}

.check input {
  accent-color: currentColor;
}

/* =========================
   MAIN PANELS
   ========================= */

.layout {
  display: grid;
  grid-template-columns: 1fr 420px;
  gap: 14px;
  padding: 14px;
  transition:
    grid-template-columns 300ms ease,
    gap 300ms ease;
  align-items: start;
}

.layout.notes-hidden {
  grid-template-columns: 1fr 0px;
  gap: 0;
}

@media (max-width: 980px) {
  .layout {
    grid-template-columns: 1fr;
  }
  .layout.notes-hidden {
    grid-template-columns: 1fr;
  }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  box-shadow: var(--shadowSoft);
  display: flex;
  flex-direction: column;
}

/* Fixed height: layout row is 600px tall, both panels stretch to fill it */
.layout[data-fixed="true"] {
  align-items: stretch;
  grid-template-rows: 600px;
}

.layout[data-fixed="true"] .panel {
  min-height: 0;
  height: 600px;
}

.layout[data-fixed="true"] .panel .treeWrap {
  flex: 1 1 auto;
  overflow-y: auto;
  min-height: 0;
}

.layout[data-fixed="true"] .notes {
  flex: 1 1 auto;
  overflow-y: auto;
  min-height: 0;
}

.panel.side {
  min-height: unset;
}

.panelHeader {
  padding: 12px 14px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

.panelHeader .twisty {
  width: 14px;
  display: inline-flex;
  justify-content: center;
  cursor: pointer;
  user-select: none;
  color: var(--muted);
  opacity: 0.9;
}

.panelTitle {
  font-weight: 700;
}

.panelMeta {
  color: var(--muted);
  font-size: 12px;
  margin-top: 4px;
}

.hint {
  color: var(--muted);
  font-size: 12px;
}

/* =========================
   TREE
   ========================= */

.treeWrap {
  flex: 1;
  overflow: auto;
  padding: 12px;
  min-height: 0;
}

.tree {
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.55;
  letter-spacing: 0.1px;
}

.node {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 6px;
  border-radius: 6px;
}

.node:hover {
  background: var(--hoverBg);
}

.twisty {
  width: 14px;
  display: inline-flex;
  justify-content: center;
  cursor: pointer;
  user-select: none;
  color: var(--muted);
  opacity: 0.9;
}

.twisty.hidden {
  visibility: hidden;
  cursor: default;
}

.icon {
  width: 16px;
  min-width: 16px;
  height: 16px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  flex: 0 0 16px;
}

.icon img {
  width: 16px;
  height: 16px;
  display: block;
}

.label {
  cursor: default;
  user-select: text;
  white-space: nowrap;
}

.children {
  margin-left: 22px;
  display: none;
  border-left: 1px dashed var(--treeDash);
  padding-left: 10px;
}

.open > .children {
  display: block;
}

/* Scrollbars */
.treeWrap {
  scrollbar-color: var(--border) transparent;
}

.treeWrap::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

.treeWrap::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 10px;
}

.treeWrap::-webkit-scrollbar-track {
  background: transparent;
}

/* =========================
   NOTES
   ========================= */

.notes {
  padding: 12px 14px 16px;
  color: var(--muted);
  font-size: 13px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.notes code {
  font-family: var(--mono);
  color: var(--text);
  font-size: 12px;
}

/* Scrollbars for notes */
.notes {
  scrollbar-color: var(--border) transparent;
}

.notes::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

.notes::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 10px;
}

.notes::-webkit-scrollbar-track {
  background: transparent;
}

/* Collapsible sections inside notes */
.notes-section {
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  flex-shrink: 0;
}

.notes-section-title {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 8px 12px;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  background: var(--hoverBg);
  cursor: pointer;
  user-select: none;
  list-style: none;
  transition:
    background 120ms ease,
    color 120ms ease;
}

.notes-section-title::-webkit-details-marker {
  display: none;
}
.notes-section-title::marker {
  display: none;
}

.notes-section-title:hover {
  background: var(--btnHover);
  color: var(--text);
}

.notes-section-title i {
  font-size: 13px;
  opacity: 0.8;
  flex-shrink: 0;
}

.notes-section-title::after {
  content: "\F282";
  font-family: "bootstrap-icons";
  font-size: 11px;
  margin-left: auto;
  opacity: 0.5;
  transition: transform 200ms ease;
}

.notes-section[open] > .notes-section-title::after {
  transform: rotate(180deg);
}

.notes-item {
  padding: 8px 12px;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.55;
  border-top: 1px solid var(--border);
}

.notes-item b {
  color: var(--text);
  font-weight: 600;
}

/* =========================
   FOOTER
   ========================= */

.footer {
  border-top: 1px solid var(--border);
  background: var(--panel);
  margin-top: 24px;
}

.footerInner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 12px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--muted);
}

.footer a {
  color: var(--text);
  text-decoration: none;
  opacity: 0.85;
}

.footer a:hover {
  opacity: 1;
  text-decoration: underline;
}

.footerLeft,
.footerRight {
  display: flex;
  align-items: center;
  gap: 6px;
}

.footer .dot {
  opacity: 0.5;
}

.footerRight a {
  display: inline-flex;
  align-items: center;
  gap: 5px;
  padding: 5px 12px;
  border-radius: 20px;
  border: 1px solid var(--border);
  background: var(--btn);
  font-size: 12px;
  font-weight: 500;
  color: var(--muted) !important;
  text-decoration: none !important;
  opacity: 1;
  transition:
    background 150ms ease,
    color 150ms ease,
    border-color 150ms ease;
}

.footerRight a i {
  font-size: 13px;
  line-height: 1;
}

.footerRight a:hover {
  background: var(--btnHover);
  color: var(--text) !important;
  border-color: var(--muted);
  text-decoration: none !important;
}

@media (max-width: 640px) {
  .footerInner {
    flex-direction: column;
    text-align: center;
  }
}

/* =========================
   SCROLLBARS (SAFE)
   ========================= */

.treeWrap {
  scrollbar-color: var(--border) transparent;
}

.treeWrap::-webkit-scrollbar {
  width: 10px;
  height: 10px;
}

.treeWrap::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 10px;
}

.treeWrap::-webkit-scrollbar-track {
  background: transparent;
}

/* =========================
   NODE ACTION BUTTONS
   💬 comment · 🎨 color · 📋 legend
   All three follow the same pattern: hidden at opacity 0,
   revealed on .node:hover, fully opaque on self-hover.
   ========================= */

.node-comment-btn,
.node-color-btn,
.node-legend-btn {
  opacity: 0;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0 4px;
  font-size: 12px;
  line-height: 1;
  transition: opacity 0.15s;
}

.node:hover .node-comment-btn,
.node:hover .node-color-btn,
.node:hover .node-legend-btn:not(.node-legend-btn--hidden) {
  opacity: 0.6;
}

.node:hover .node-comment-btn:hover,
.node:hover .node-color-btn:hover,
.node:hover .node-legend-btn:not(.node-legend-btn--hidden):hover {
  opacity: 1;
}

/* --hidden modifier: legend button stays invisible until a color is set */
.node-legend-btn--hidden {
  pointer-events: none;
}

/* =========================
   COMMENT ANNOTATION + EDITOR
   ========================= */

.node-comment-annotation {
  margin-left: 8px;
  font-size: 0.8em;
  color: var(--muted);
  font-style: italic;
  white-space: nowrap;
}

.node-comment-editor,
.node-legend-editor {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  margin-left: 8px;
}

.node-comment-input,
.node-legend-input {
  font-size: 0.8em;
  padding: 1px 5px;
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--panel);
  color: var(--text);
  width: 180px;
}

.node-comment-confirm,
.node-legend-save {
  background: rgba(105, 219, 124, 0.15);
  border: 1px solid rgba(105, 219, 124, 0.4);
  border-radius: 4px;
  cursor: pointer;
  padding: 1px 5px;
  font-size: 11px;
  color: var(--text);
}

.node-comment-delete,
.node-legend-clear {
  background: rgba(255, 107, 107, 0.15);
  border: 1px solid rgba(255, 107, 107, 0.4);
  border-radius: 4px;
  cursor: pointer;
  padding: 1px 5px;
  font-size: 11px;
  color: var(--text);
}

.node-comment-confirm:hover,
.node-legend-save:hover {
  background: rgba(105, 219, 124, 0.3);
}

.node-comment-delete:hover,
.node-legend-clear:hover {
  background: rgba(255, 107, 107, 0.3);
}

/* =========================
   COLOR PALETTE (horizontal strip)
   ========================= */

.node-color-palette {
  display: inline-flex;
  flex-direction: row;
  align-items: center;
  gap: 4px;
  margin-left: 6px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 3px 6px;
}

.node-color-swatch {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  border: 2px solid transparent;
  cursor: pointer;
  padding: 0;
  transition:
    transform 0.1s,
    border-color 0.1s;
}

.node-color-swatch:hover {
  transform: scale(1.25);
}

.node-color-swatch.active {
  border-color: var(--text);
}

.node-color-clear {
  background: none;
  color: var(--muted);
  font-size: 10px;
  width: 14px;
  height: 14px;
  line-height: 1;
}

.node-color-divider {
  display: inline-block;
  width: 1px;
  height: 14px;
  background: var(--border);
  margin: 0 2px;
  vertical-align: middle;
}

.node-folder-highlight-toggle {
  background: none;
  border: 1px solid var(--border);
  border-radius: 4px;
  cursor: pointer;
  padding: 1px 5px;
  font-size: 11px;
  color: var(--text);
  white-space: nowrap;
}

.node-folder-highlight-toggle:hover {
  background: var(--btnHover);
}

/* =========================
   HIGHLIGHT STYLING
   ========================= */

.node.node-highlighted {
  background: var(--node-highlight, transparent);
  border-left: 3px solid var(--node-highlight-border, transparent);
  padding-left: 4px;
  border-radius: 4px;
}

.children.children-highlighted {
  background: var(--folder-highlight, transparent);
  border-left: 3px solid var(--folder-highlight-border, transparent);
  border-radius: 0 4px 4px 0;
  margin-left: 2px;
}

/* Legend input error state */
.node-legend-input--error {
  border-color: #ff6b6b;
  outline: none;
  box-shadow: 0 0 0 2px rgba(255, 107, 107, 0.25);
}

/* =========================
   PANEL HEADER CONTROLS
   ========================= */

.panel-header-controls {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

/* =========================
   CLEAR-ALL BUTTONS
   ========================= */

.btn-clear-all {
  font-size: 11px;
  padding: 4px 8px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--btn);
  color: var(--muted);
  cursor: pointer;
  transition:
    background 120ms ease,
    color 120ms ease;
}

.btn-clear-all:hover {
  background: rgba(255, 107, 107, 0.15);
  border-color: rgba(255, 107, 107, 0.4);
  color: var(--text);
}

/* =========================
   KO-FI BUTTON
   ========================= */

.footerCenter {
  display: flex;
  align-items: center;
  justify-content: center;
}

.kofi-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 20px;
  border: 1px solid rgba(255, 94, 91, 0.4);
  background: rgba(255, 94, 91, 0.1);
  color: var(--text) !important;
  font-size: 12px;
  font-weight: 500;
  text-decoration: none !important;
  opacity: 0.85;
  transition:
    background 150ms ease,
    opacity 150ms ease,
    border-color 150ms ease;
}

.kofi-btn:hover {
  background: rgba(255, 94, 91, 0.2);
  border-color: rgba(255, 94, 91, 0.7);
  opacity: 1;
  text-decoration: none !important;
}

@media (max-width: 640px) {
  .footerCenter {
    order: -1;
  }
}

/* =========================
   NOTES PANEL TOGGLE
   ========================= */

.notes-close-btn {
  background: none;
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--muted);
  cursor: pointer;
  padding: 4px 7px;
  font-size: 12px;
  line-height: 1;
  margin-left: auto;
  transition:
    background 120ms ease,
    color 120ms ease;
}

.notes-close-btn:hover {
  background: var(--btnHover);
  color: var(--text);
}

/* The side panel slides out to the right */
.panel.side.notes-panel--collapsed {
  transform: translateX(100%);
  opacity: 0;
  pointer-events: none;
  height: 0;
  min-height: 0;
  overflow: hidden;
  visibility: hidden;
}

/* Reopen button — fixed tab on the right edge of the viewport */
.notes-reopen-btn {
  display: none;
  position: fixed;
  top: 80px;
  right: 0;
  background: var(--panel);
  border: 1px solid var(--border);
  border-right: none;
  border-radius: 8px 0 0 8px;
  color: var(--muted);
  cursor: pointer;
  padding: 10px 8px;
  font-size: 15px;
  line-height: 1;
  box-shadow: var(--shadowSoft);
  transition:
    background 120ms ease,
    color 120ms ease;
  z-index: 20;
}

.notes-reopen-btn--visible {
  display: block;
}

.notes-reopen-btn:hover {
  background: var(--btnHover);
  color: var(--text);
}

/* =========================
   CUSTOM THEME DROPDOWN
   ========================= */

.theme-select-wrap {
  position: relative;
  display: inline-block;
}

.theme-select-trigger {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 6px;
  padding: 7px 10px;
  font-size: 12px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--btn);
  color: var(--text);
  cursor: pointer;
  transition: background 120ms ease;
  white-space: nowrap;
  min-width: 80px;
}

.theme-select-trigger:hover {
  background: var(--btnHover);
}

.theme-select-arrow {
  font-size: 10px;
  color: var(--muted);
  display: flex;
  align-items: center;
  transition: transform 150ms ease;
}

.theme-select-trigger[aria-expanded="true"] .theme-select-arrow {
  transform: rotate(180deg);
}

.theme-select-panel {
  display: none;
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  min-width: 100%;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  box-shadow: var(--shadow);
  overflow: hidden;
  z-index: 100;
}

.theme-select-panel.open {
  display: block;
}

.theme-select-option {
  padding: 8px 14px;
  font-size: 12px;
  color: var(--text);
  cursor: pointer;
  transition: background 100ms ease;
}

.theme-select-option:hover {
  background: var(--hoverBg);
}

.theme-select-option.active {
  color: var(--accent);
  font-weight: 600;
}