:root {
  --bg: #0e0e11;
  --bar: #1b1b20;
  --side: #141418;
  --line: #2c2c34;
  --text: #e8e8ee;
  --muted: #8a8a96;
  --accent: #8b7bff;
  --danger: #ff7b72;
  --todo: #6b6b78;
  --doing: #e0a23a;
  --done: #3fb950;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html, body {
  margin: 0; height: 100%; overflow: hidden; background: var(--bg); color: var(--text);
  font: 14px/1.45 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-tap-highlight-color: transparent; overscroll-behavior: none;
}
button, input, select, textarea { font: inherit; color: inherit; }
button { cursor: pointer; }
[hidden] { display: none !important; }
.grow { flex: 1; }
.muted { color: var(--muted); }
.small { font-size: 12px; }
code { font: 12.5px/1.5 ui-monospace, Consolas, monospace; }

input, select, textarea {
  width: 100%; background: #0f0f13; border: 1px solid var(--line); border-radius: 8px; padding: 8px 10px; outline: none;
}
input:focus, select:focus, textarea:focus { border-color: var(--accent); }
textarea { resize: vertical; }
label { display: block; color: var(--muted); font-size: 12px; margin-bottom: 12px; }
label input, label select, label textarea { margin-top: 4px; color: var(--text); font-size: 14px; }
label small { font-size: 11px; }

button.primary, #login button { background: var(--accent); color: #fff; border: 0; border-radius: 8px; padding: 8px 14px; font-weight: 600; }
button.subtle { background: none; border: 1px solid var(--line); border-radius: 8px; padding: 6px 10px; color: var(--muted); }
button.danger { color: var(--danger); }

/* login */
#login { position: fixed; inset: 0; display: grid; place-items: center; }
#login form { width: min(320px, calc(100% - 32px)); display: grid; gap: 10px; }
#login h1 { margin: 0 0 8px; font-size: 22px; }
#login .err { color: var(--danger); min-height: 1em; margin: 0; }

/* layout */
#app { position: fixed; inset: 0; display: flex; }
#sidebar {
  width: 270px; flex-shrink: 0; background: var(--side); border-right: 1px solid var(--line);
  display: flex; flex-direction: column; padding: 10px; padding-top: calc(10px + env(safe-area-inset-top)); gap: 8px;
}
.side-head { display: flex; align-items: center; gap: 6px; font-size: 15px; padding: 2px 4px; }
.side-actions { display: flex; gap: 6px; }
.side-actions button { flex: 1; background: var(--bar); border: 1px solid var(--line); border-radius: 8px; padding: 7px; }
button.icon { width: 34px; height: 34px; border: 0; border-radius: 8px; background: none; display: grid; place-items: center; }
button.icon:hover { background: #ffffff10; }
svg { width: 20px; height: 20px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }

#tree { flex: 1; overflow-y: auto; margin: 0 -4px; padding: 0 4px 20px; }
.node { display: flex; align-items: center; gap: 6px; padding: 6px 8px; border-radius: 7px; cursor: pointer; user-select: none; min-height: 32px; }
.node:hover { background: #ffffff0a; }
.node.active { background: #8b7bff26; }
.node.drop { outline: 2px dashed var(--accent); }
.node .name { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.node .caret { width: 12px; color: var(--muted); font-size: 10px; transition: transform .15s; }
.node.open .caret { transform: rotate(90deg); }
.node.folder .name { font-weight: 600; }
.node .acts { display: none; gap: 2px; }
.node:hover .acts { display: flex; }
@media (hover: none) { .node .acts { display: flex; } }
.node .acts button { border: 0; background: none; color: var(--muted); padding: 0 5px; font-size: 15px; }
.dot { width: 9px; height: 9px; border-radius: 50%; flex-shrink: 0; background: var(--todo); }
.dot.doing { background: var(--doing); }
.dot.done { background: var(--done); }
.badge { font-size: 11px; background: var(--accent); color: #fff; border-radius: 9px; padding: 0 6px; }
.children { margin-left: 14px; border-left: 1px solid var(--line); padding-left: 4px; }
#tree .root-drop { min-height: 30px; }

#main { flex: 1; min-width: 0; position: relative; display: flex; flex-direction: column; }
#empty { margin: auto; text-align: center; max-width: 420px; padding: 20px; color: var(--muted); }
#empty h2 { color: var(--text); font-weight: 600; }
#empty button { margin-top: 10px; background: var(--accent); color: #fff; border: 0; border-radius: 8px; padding: 10px 18px; font-weight: 600; }

/* board (toolbar styles from InkVault's tablet client) */
#board { flex: 1; display: flex; flex-direction: column; min-height: 0; user-select: none; -webkit-user-select: none; }
#toolbar {
  display: flex; align-items: center; gap: 6px; padding: 6px 10px;
  padding-top: calc(6px + env(safe-area-inset-top));
  background: var(--bar); border-bottom: 1px solid var(--line);
  overflow-x: auto; scrollbar-width: none; flex-shrink: 0; touch-action: pan-x;
}
#toolbar::-webkit-scrollbar { display: none; }
#toolbar button {
  flex-shrink: 0; width: 40px; height: 40px; border-radius: 10px; border: 0; background: transparent;
  display: grid; place-items: center;
}
#toolbar button:active { background: #ffffff14; }
#toolbar button.on { background: #8b7bff2e; color: var(--accent); }
#toolbar button:disabled { opacity: .35; }
#toolbar button.text { width: auto; padding: 0 14px; background: #ffffff10; font-weight: 600; }
#toolbar button.text.on { background: var(--accent); color: #fff; }
#toolbar svg { width: 22px; height: 22px; }
#toolbar svg circle { fill: currentColor; stroke: none; }
#toolbar svg .hl { stroke: #ffd60a; stroke-width: 3; }
#title { color: var(--muted); max-width: 22ch; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; flex-shrink: 1; min-width: 0; }
.group { display: flex; align-items: center; gap: 2px; flex-shrink: 0; }
.sep { width: 1px; height: 26px; background: var(--line); flex-shrink: 0; margin: 0 4px; }
#toolbar .swatch { width: 34px; height: 40px; }
#toolbar .swatch::before {
  content: ""; width: 22px; height: 22px; border-radius: 50%; background: var(--c);
  box-shadow: inset 0 0 0 1px #ffffff30;
}
#toolbar .swatch.on::before { box-shadow: 0 0 0 2px var(--bar), 0 0 0 4px var(--text); }
#toolbar .swatch.custom { display: grid; place-items: center; position: relative; cursor: pointer; }
#toolbar .swatch.custom::before { background: conic-gradient(#f44, #fd4, #4f6, #4df, #64f, #f4d, #f44); }
#toolbar .swatch.custom input { position: absolute; inset: 0; opacity: 0; width: 100%; height: 100%; cursor: pointer; padding: 0; }
#toolbar .size i { display: block; border-radius: 50%; background: currentColor; }
#toolbar .dash { width: 34px; }
#toolbar .dash svg { stroke-width: 2.4; }

#menu {
  position: fixed; right: 10px; top: calc(56px + env(safe-area-inset-top)); z-index: 10; width: 290px;
  background: var(--bar); border: 1px solid var(--line); border-radius: 12px; padding: 6px;
  box-shadow: 0 12px 40px #0009;
}
#menu .row { display: flex; gap: 10px; align-items: center; width: 100%; padding: 10px; border: 0; border-radius: 8px; background: none; text-align: left; color: var(--text); font-size: 14px; margin: 0; }
#menu .row:hover { background: #ffffff10; }
#menu .danger { color: var(--danger); }
#menu hr { border: 0; border-top: 1px solid var(--line); margin: 4px 0; }
#menu input[type=checkbox] { width: 18px; height: 18px; accent-color: var(--accent); margin: 0; }
#menu .hint { color: var(--muted); font-size: 12px; margin: 6px 10px 4px; }

.board-row { flex: 1; display: flex; min-height: 0; }
#stage { position: relative; flex: 1; overflow: hidden; background: #2a2a30; touch-action: none; }
#stage.drop { outline: 3px dashed var(--accent); outline-offset: -8px; }
#stage canvas { position: absolute; inset: 0; width: 100%; height: 100%; }
#live { cursor: none; }
#texts { position: absolute; left: 0; top: 0; transform-origin: 0 0; pointer-events: none; }
#texts .txt { position: absolute; line-height: 1.4; font-family: "Segoe Print", "Bradley Hand", system-ui, sans-serif; overflow-wrap: anywhere; }
#texts .txt.claude { font-family: system-ui, -apple-system, "Segoe UI", sans-serif; }
#texts .txt.claude::before { content: "Claude"; position: absolute; left: 0; top: -1.15em; font: 600 .5em system-ui, sans-serif; letter-spacing: .04em; opacity: .7; }
#texts .txt p { margin: 0 0 .3em; }
#texts .txt.moving { opacity: .8; }

#selbar {
  position: fixed; z-index: 15; display: flex; gap: 2px; padding: 4px;
  background: var(--bar); border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 8px 28px #0008;
}
#selbar button { border: 0; background: none; padding: 9px 14px; border-radius: 8px; font-size: 15px; }
#selbar button:hover { background: #ffffff14; }
#selbar .danger { color: var(--danger); }

/* side panel */
#panel {
  width: 360px; flex-shrink: 0; border-left: 1px solid var(--line); background: var(--side);
  display: flex; flex-direction: column; min-height: 0; user-select: text; -webkit-user-select: text;
}
.tabs { display: flex; border-bottom: 1px solid var(--line); flex-shrink: 0; }
.tabs button { flex: 1; padding: 11px 6px; border: 0; background: none; color: var(--muted); border-bottom: 2px solid transparent; }
.tabs button.on { color: var(--text); border-bottom-color: var(--accent); }
#claude-badge { display: inline-block; width: 7px; height: 7px; border-radius: 50%; background: var(--accent); vertical-align: middle; }
.tab { flex: 1; overflow-y: auto; padding: 14px; }
.row2 { display: flex; gap: 10px; }
.row2 label { flex: 1; min-width: 0; }

#ask textarea { margin-bottom: 8px; }
.ask-row { display: flex; align-items: center; gap: 10px; }
#manual { background: #8b7bff14; border: 1px solid #8b7bff55; border-radius: 10px; padding: 10px; margin: 12px 0; }
#manual p { margin: 0 0 6px; }
#manual code { display: block; background: #0008; padding: 8px; border-radius: 6px; margin-bottom: 6px; word-break: break-word; }
#manual button { background: var(--accent); color: #fff; border: 0; border-radius: 6px; padding: 5px 12px; }
.question { display: flex; gap: 8px; align-items: flex-start; padding: 8px 10px; border-radius: 8px; background: #ffffff08; margin-top: 10px; }
.question .q { flex: 1; }
.question button { border: 0; background: none; color: var(--muted); }
.note { border-top: 1px solid var(--line); padding: 12px 0 4px; margin-top: 12px; }
.note-head { display: flex; align-items: center; gap: 8px; color: var(--muted); font-size: 12px; margin-bottom: 4px; }
.note-head button { border: 0; background: none; color: var(--muted); margin-left: auto; }
.md { overflow-wrap: anywhere; }
.md p { margin: .5em 0; }
.md pre { background: #0008; padding: 8px; border-radius: 6px; overflow-x: auto; }
.md code { background: #ffffff10; padding: 1px 4px; border-radius: 4px; }
.md pre code { background: none; padding: 0; }
.md .katex-display { overflow-x: auto; overflow-y: hidden; padding: 2px 0; }
.md blockquote { margin: .5em 0; padding-left: 10px; border-left: 3px solid var(--line); color: var(--muted); }
.md h1, .md h2, .md h3 { font-size: 15px; margin: .8em 0 .3em; }
#read-box { margin-top: 18px; border-top: 1px solid var(--line); padding-top: 10px; }
#read-box summary { cursor: pointer; color: var(--muted); }
#read-list .t { padding: 6px 0; border-bottom: 1px solid #ffffff0a; font-size: 13px; }
.read-actions { display: flex; gap: 8px; margin-top: 10px; flex-wrap: wrap; }
.read-actions button { background: var(--bar); border: 1px solid var(--line); border-radius: 8px; padding: 6px 10px; }

.calc-head { display: flex; align-items: center; gap: 8px; margin-bottom: 8px; }
.calc-head a { color: var(--accent); text-decoration: none; }
#calc-lines { padding-left: 22px; margin: 0; }
#calc-lines li { padding: 6px 0; border-bottom: 1px solid #ffffff0a; }
#calc-lines .lbl { color: var(--muted); font-size: 12px; margin-right: 6px; }
#calc-unlinked button { margin-bottom: 14px; }

dialog {
  background: var(--bar); color: var(--text); border: 1px solid var(--line); border-radius: 14px;
  width: min(640px, calc(100% - 32px)); max-height: calc(100% - 40px); padding: 18px 20px; box-shadow: 0 20px 60px #000c;
}
dialog::backdrop { background: #0009; }
dialog h2 { margin-top: 0; font-size: 17px; }
dialog h3 { font-size: 14px; margin: 16px 0 6px; }
dialog code { display: block; background: #0008; padding: 10px; border-radius: 8px; white-space: pre-wrap; word-break: break-all; user-select: all; }
dialog form { text-align: right; margin-top: 14px; }
dialog ol { padding-left: 20px; }
dialog ol code { margin: 6px 0; }
.token-row { display: flex; gap: 8px; align-items: center; margin-top: 8px; }
.token-row input { flex: 1; }
#preview-body figure { margin: 0 0 14px; }
#preview-body img { max-width: 100%; background: #fff; border-radius: 4px; display: block; }
#preview-body figcaption { color: var(--muted); font-size: 12px; margin-top: 4px; }

#toast {
  position: fixed; left: 50%; bottom: calc(30px + env(safe-area-inset-bottom)); transform: translateX(-50%);
  background: #000d; color: #fff; padding: 8px 16px; border-radius: 20px; opacity: 0; transition: opacity .2s; pointer-events: none;
  z-index: 30; max-width: calc(100% - 32px); text-align: center;
}
#toast.show { opacity: 1; }

/* narrow screens / tablets in portrait: sidebar and panel slide over the page */
#side-toggle { display: none !important; }
@media (max-width: 1100px) {
  #panel { position: absolute; right: 0; top: 53px; bottom: 0; z-index: 8; box-shadow: -10px 0 40px #0008; }
  #main:not(.panel-open) #panel { display: none; }
}
@media (max-width: 800px) {
  #side-toggle { display: grid !important; }
  #sidebar { position: fixed; left: 0; top: 0; bottom: 0; z-index: 20; transform: translateX(-100%); transition: transform .2s; box-shadow: 10px 0 40px #0009; }
  #app.side-open #sidebar { transform: none; }
  #panel { width: min(360px, 100%); }
  #title { display: none; }
}
@media (min-width: 1101px) {
  #main:not(.panel-open) #panel { display: none; }
}

/* sidebar footer: follow switch and links to the three apps */
.side-foot { border-top: 1px solid var(--line); padding-top: 8px; display: grid; gap: 6px; }
.side-foot .follow-btn { border: 1px solid var(--line); background: none; border-radius: 8px; padding: 7px; color: var(--muted); }
.side-foot .follow-btn.on { border-color: var(--accent); color: var(--accent); }
.side-foot .apps { font-size: 12px; color: var(--muted); text-align: center; }
.side-foot a { color: var(--accent); text-decoration: none; }
#toolbar .follow-btn { font-size: 13px; color: var(--muted); }
#toolbar .follow-btn.on { background: #8b7bff2e; color: var(--accent); }
#stage.readonly #live { cursor: grab; }

/* ---- tablet app: the page fills the screen; problems and panel are slide-in menus ---- */
html[data-mode="tablet"] #side-toggle,
html[data-mode="phone"] #side-toggle { display: grid !important; }
html[data-mode="tablet"] #sidebar,
html[data-mode="phone"] #sidebar {
  position: fixed; left: 0; top: 0; bottom: 0; z-index: 20; width: min(300px, 86vw);
  transform: translateX(-100%); transition: transform .2s; box-shadow: 10px 0 40px #0009;
}
html[data-mode="tablet"] #app.side-open #sidebar,
html[data-mode="phone"] #app.side-open #sidebar { transform: none; }
html[data-mode="tablet"] #panel {
  position: absolute; right: 0; top: 53px; bottom: 0; z-index: 8; width: min(380px, 90vw); box-shadow: -10px 0 40px #0008;
}
html[data-mode="tablet"] #main:not(.panel-open) #panel { display: none; }
html[data-mode="tablet"] #empty { padding-top: 70px; }
/* the two menu buttons first, so they never scroll off a narrow toolbar */
html[data-mode="tablet"] #side-toggle { order: -3; }
html[data-mode="tablet"] #panel-toggle { order: -2; }
#empty-menu { display: none; margin-left: 8px; }
html[data-mode="tablet"] #empty-menu, html[data-mode="phone"] #empty-menu { display: inline-block; }
@media (max-width: 800px) { #empty-menu { display: inline-block; } }

/* ---- phone app: problems, Claude and CalcVault; the page is a small read-only view ---- */
html[data-mode="phone"] #toolbar .tools,
html[data-mode="phone"] #toolbar .sep,
html[data-mode="phone"] #colors,
html[data-mode="phone"] #sizes,
html[data-mode="phone"] #dashes,
html[data-mode="phone"] #add-image,
html[data-mode="phone"] #paste,
html[data-mode="phone"] #undo,
html[data-mode="phone"] #redo,
html[data-mode="phone"] #more,
html[data-mode="phone"] #panel-toggle { display: none !important; }
html[data-mode="phone"] #title { display: block !important; flex: 1; max-width: none; color: var(--text); font-weight: 600; }
html[data-mode="phone"] .board-row { flex-direction: column; }
html[data-mode="phone"] #toolbar .grow { display: none; }
html[data-mode="phone"] #stage { flex: none; height: 34vh; border-bottom: 1px solid var(--line); }
html[data-mode="phone"] #panel {
  position: static; display: flex !important; width: 100%; flex: 1; min-height: 0; border-left: 0; box-shadow: none;
}
html[data-mode="phone"] .tab { padding-bottom: calc(14px + env(safe-area-inset-bottom)); }