/* Calculus Workbook
   Two panes and nothing else: your textbook on one side, one long sheet of
   paper on the other. All the chrome floats, so every pixel of height and
   width goes to the work. */

:root {
  --paper:      #faf8f4;
  --paper-2:    #f3f0e9;
  --paper-3:    #ebe7dd;
  --sheet:      #ffffff;
  --ink:        #17150f;
  --ink-2:      #5d574b;
  --ink-3:      #948c7c;
  --line:       #e6e1d5;
  --line-2:     #cec7b6;

  --todo:  #c98a10;
  --doing: #3358c4;
  --done:  #2c8250;
  --stuck: #b83a3a;

  --serif: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Constantia, Georgia, serif;
  --sans:  "Segoe UI", -apple-system, BlinkMacSystemFont, "Helvetica Neue", sans-serif;
  --mono:  "Cascadia Mono", "SF Mono", Consolas, "Liberation Mono", monospace;

  --r:   6px;
  --r-s: 4px;
  --shadow-1: 0 1px 2px rgba(23, 21, 15, .06);
  --shadow-2: 0 10px 30px -14px rgba(23, 21, 15, .45);
  --shadow-3: 0 30px 70px -24px rgba(23, 21, 15, .5);
  --ring: 0 0 0 3px rgba(23, 21, 15, .13);

  --split: 52%;
  --dock: 30vh;
  --book-zoom: 1;
  --rail: 46px;
}

* { box-sizing: border-box; min-width: 0; }
[hidden] { display: none !important; }
html, body { height: 100%; margin: 0; }
body {
  background: var(--paper);
  color: var(--ink);
  font: 400 13.5px/1.55 var(--sans);
  overflow: hidden;
  -webkit-font-smoothing: antialiased;
}
::selection { background: #f0e3bd; }
:focus-visible { outline: none; box-shadow: var(--ring); border-radius: var(--r-s); }

/* ============================================================== atoms */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  height: 30px; padding: 0 12px;
  font: 500 12.5px/1 var(--sans); color: var(--ink); white-space: nowrap;
  background: linear-gradient(180deg, #fff, var(--paper-2));
  border: 1px solid var(--line-2); border-radius: var(--r);
  box-shadow: var(--shadow-1); cursor: pointer;
  transition: background .13s, border-color .13s, transform .06s, box-shadow .13s;
}
.btn:hover { border-color: var(--ink-3); background: #fff; }
.btn:active { transform: translateY(1px); box-shadow: none; }
.btn.primary { color: var(--paper); background: var(--ink); border-color: var(--ink); }
.btn.primary:hover { background: #2c2820; }
.btn.primary:disabled { opacity: .38; cursor: not-allowed; transform: none; }
.btn.ghost { background: transparent; border-color: transparent; box-shadow: none; color: var(--ink-2); }
.btn.ghost:hover { background: var(--paper-3); color: var(--ink); }
.btn.danger { color: var(--stuck); }
.btn.danger:hover { background: #fbecec; }

.input, .select, .code {
  height: 30px; padding: 0 10px; width: 100%;
  font: 400 12.5px/1 var(--sans); color: var(--ink);
  background: #fff; border: 1px solid var(--line-2); border-radius: var(--r);
  box-shadow: inset 0 1px 2px rgba(23,21,15,.04);
  transition: border-color .13s, box-shadow .13s;
}
.input:hover, .select:hover { border-color: var(--ink-3); }
.input:focus, .select:focus, .code:focus { outline: none; border-color: var(--ink); box-shadow: var(--ring); }
.input:disabled { background: var(--paper-2); color: var(--ink-3); }
.input::placeholder { color: var(--ink-3); }
.select {
  appearance: none; padding-right: 28px; cursor: pointer;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='10' height='7'%3E%3Cpath d='M1 1l4 4 4-4' fill='none' stroke='%235d574b' stroke-width='1.5' stroke-linecap='round'/%3E%3C/svg%3E");
  background-repeat: no-repeat; background-position: right 10px center;
}
.code { height: auto; min-height: 96px; padding: 9px 10px; resize: vertical; font: 400 11.5px/1.6 var(--mono); }
.code.tall { min-height: 260px; }

.filebtn { display: inline-block; position: relative; }
.filebtn input { position: absolute; inset: 0; opacity: 0; cursor: pointer; }
.filebtn span {
  display: inline-flex; align-items: center; height: 32px; padding: 0 14px;
  font: 500 12.5px/1 var(--sans);
  border: 1px dashed var(--line-2); border-radius: var(--r);
  background: #fff; color: var(--ink-2);
}
.filebtn:hover span { border-color: var(--ink); color: var(--ink); }
.filebtn.small span { height: 28px; font-size: 12px; }

.seg-ctl { display: inline-flex; padding: 2px; gap: 2px; background: var(--paper-3); border-radius: var(--r); }
.seg-ctl button {
  height: 22px; padding: 0 9px; border: 0; border-radius: 3px;
  font: 500 11.5px/1 var(--sans); color: var(--ink-2);
  background: transparent; cursor: pointer; transition: background .13s, color .13s;
}
.seg-ctl button:hover { color: var(--ink); }
.seg-ctl button.on { background: #fff; color: var(--ink); box-shadow: var(--shadow-1); }

.tag { display: inline-flex; align-items: center; height: 22px; padding: 0 8px;
  font: 500 11px/1 var(--sans); color: var(--ink-2); background: var(--paper-3); border-radius: 99px; }
.dot { display: inline-block; width: 7px; height: 7px; border-radius: 50%; }
.dot.is-todo { background: var(--todo); } .dot.is-doing { background: var(--doing); }
.dot.is-done { background: var(--done); } .dot.is-stuck { background: var(--stuck); }

.track { display: flex; height: 3px; border-radius: 2px; background: var(--line); overflow: hidden; }
.track.big { height: 4px; }
.track .seg { height: 100%; transition: width .25s ease; }
.seg.is-todo { background: var(--todo); } .seg.is-doing { background: var(--doing); }
.seg.is-done { background: var(--done); } .seg.is-stuck { background: var(--stuck); }

.warn { color: var(--stuck); }
.ok { color: var(--done); }
.note { color: var(--ink-2); font-size: 12.5px; margin: 0 0 12px; max-width: 62ch; }
.msg { min-height: 18px; font-size: 12px; color: var(--ink-2); margin: 8px 0 0; }
.grow { flex: 1; }

/* =============================================================== gate */
#gate {
  position: fixed; inset: 0; overflow-y: auto; padding: 40px 20px; z-index: 40;
  background:
    radial-gradient(1100px 600px at 15% -10%, #fff 0%, transparent 60%),
    repeating-linear-gradient(0deg, transparent 0 27px, rgba(23,21,15,.035) 27px 28px),
    var(--paper);
}
.gate-card {
  max-width: 640px; margin: 0 auto; background: var(--sheet);
  border: 1px solid var(--line); border-radius: 12px; box-shadow: var(--shadow-3); overflow: hidden;
}
.gate-card > header { padding: 36px 40px 26px; border-bottom: 1px solid var(--line); }
.mark { width: 42px; height: 42px; display: grid; place-items: center; margin-bottom: 16px;
  font: 400 26px/1 var(--serif); color: var(--paper); background: var(--ink); border-radius: 10px; }
.gate-card h1 { margin: 0; font: 400 30px/1.1 var(--serif); letter-spacing: -.01em; }
.lede { margin: 10px 0 0; color: var(--ink-2); font-size: 14px; max-width: 46ch; }
.steps { list-style: none; margin: 0; padding: 8px 40px 4px; }
.steps li { padding: 20px 0; border-bottom: 1px solid var(--line); }
.steps li:last-child { border-bottom: 0; }
.steps h2 { display: flex; align-items: center; gap: 10px; margin: 0 0 6px; font: 500 14px/1.3 var(--sans); }
.step-n { display: grid; place-items: center; width: 20px; height: 20px; flex: none;
  font: 500 11px/1 var(--mono); color: var(--ink-2); background: var(--paper-3); border-radius: 50%; }
.steps p { margin: 0 0 12px 30px; color: var(--ink-2); font-size: 12.8px; max-width: 54ch; }
.steps .select, .steps .filebtn { margin-left: 30px; }
.steps .select { max-width: 380px; }
.filestate { margin: 10px 0 0 30px !important; font-size: 12px; }
.gate-card > footer { padding: 20px 40px 28px; }
.gate-card > footer .btn { height: 38px; padding: 0 20px; font-size: 13.5px; }

/* ========================================================== workspace */
#workspace { display: flex; height: 100%; position: relative; }
.pane { display: flex; flex-direction: column; min-width: 0; position: relative; }
.pane-book { flex: 0 0 var(--split); order: 1; background: var(--paper-2); }
.splitter { flex: 0 0 7px; order: 2; cursor: col-resize; background: var(--paper-3);
  border-left: 1px solid var(--line); border-right: 1px solid var(--line); position: relative; }
.splitter::after {
  content: ""; position: absolute; top: 50%; left: 50%; width: 3px; height: 34px;
  transform: translate(-50%, -50%); border-radius: 2px; background: var(--line-2);
}
.splitter:hover::after, .splitter.dragging::after { background: var(--ink-3); }
.splitter.dragging { background: var(--line); }
.pane-sheet { flex: 1 1 0; order: 3; background: var(--paper); flex-direction: row; }
.sheet-main { flex: 1; display: flex; flex-direction: column; min-width: 0; }

#workspace[data-swapped] .pane-book { order: 3; }
#workspace[data-swapped] .pane-sheet { order: 1; }
#workspace[data-layout="book"] .pane-sheet,
#workspace[data-layout="book"] .splitter { display: none; }
#workspace[data-layout="book"] .pane-book { flex: 1 1 auto; }
#workspace[data-layout="sheet"] .pane-book,
#workspace[data-layout="sheet"] .splitter { display: none; }
#workspace[data-layout="sheet"] .pane-sheet { flex: 1 1 auto; }

/* ---------------------------------------------------------------- HUD */
.hud {
  position: absolute; left: 12px; bottom: 12px; z-index: 25;
  display: flex; align-items: center; gap: 6px; padding: 4px 6px 4px 10px;
  background: rgba(250, 248, 244, .84); backdrop-filter: blur(10px) saturate(1.2);
  border: 1px solid var(--line-2); border-radius: 99px; box-shadow: var(--shadow-2);
  opacity: .58; transition: opacity .16s;
}
.hud:hover, .hud:focus-within { opacity: 1; }
.hud-progress { display: flex; align-items: center; gap: 7px; }
.hud-progress .track { width: 84px; }
.hud-progress span { font: 500 11px/1 var(--mono); color: var(--ink-2); }
.hud-sep { width: 1px; height: 18px; background: var(--line-2); margin: 0 2px; }
.icon {
  width: 26px; height: 26px; display: grid; place-items: center;
  font-size: 13px; color: var(--ink-2); background: transparent;
  border: 0; border-radius: 50%; cursor: pointer; transition: background .12s, color .12s;
}
.icon:hover { background: var(--paper-3); color: var(--ink); }
.savestate { font: 400 10px/1 var(--mono); color: var(--ink-3); padding-right: 6px; min-width: 32px; }

/* --------------------------------------------------------- book pane */
.pages { flex: 1; overflow: auto; padding: 14px 0 40px; overscroll-behavior: contain; }
.banner { order: -1; margin: 0; padding: 7px 14px; font-size: 12px; color: #7a5a12;
  background: #fdf4dd; border-bottom: 1px solid #eedfae; }
.sheet { width: calc(min(97%, 960px) * var(--book-zoom)); margin: 0 auto 18px;
  min-width: min(97%, 320px); transition: width .12s ease-out; }
.sheet-tab { display: flex; align-items: baseline; gap: 8px; padding: 0 2px 5px; font-size: 11px; color: var(--ink-3); }
.sheet-tab b { flex: none; font: 600 11.5px/1 var(--mono); color: var(--ink); }
.sheet-tab i { font-style: normal; }
.sheet-tab span { color: var(--ink-2); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.sheet-tab em { margin-left: auto; flex: none; font: 400 10.5px/1 var(--mono); font-style: normal; }
.sheet-body { position: relative; background: var(--sheet); border: 1px solid var(--line-2);
  border-radius: 3px; box-shadow: var(--shadow-2); }
.sheet-body canvas { display: block; width: 100%; height: auto; }

.hot { position: absolute; padding: 0; border: 0; border-radius: 3px; cursor: pointer; background: transparent; }
.hot::after { content: ""; position: absolute; inset: -2px; border-radius: 3px; background: currentColor; opacity: .34; }
.hot:hover { box-shadow: 0 0 0 2px var(--ink); }
.hot.picked { box-shadow: 0 0 0 2px var(--ink), 0 0 0 6px rgba(23,21,15,.13); }
.hot.ghost { padding: 1px 5px; font: 600 10px/1.3 var(--mono); color: var(--ink); border: 1px dashed currentColor; }
.hot.ghost::after { opacity: .1; }
.hot.is-todo { color: var(--todo); } .hot.is-doing { color: var(--doing); }
.hot.is-done { color: var(--done); } .hot.is-stuck { color: var(--stuck); }

/* -------------------------------------------------------- sheet pane */
.sheet-bar {
  display: flex; align-items: center; gap: 10px; padding: 7px 10px;
  border-bottom: 1px solid var(--line); background: var(--paper-2);
}
.jump { position: relative; flex: none; }
.jump-btn {
  display: flex; align-items: center; gap: 7px; height: 26px; padding: 0 9px;
  list-style: none; cursor: pointer; border-radius: var(--r);
  background: #fff; border: 1px solid var(--line-2); max-width: 250px;
}
.jump-btn::-webkit-details-marker { display: none; }
.jump-btn:hover { border-color: var(--ink-3); }
.jump-btn b { flex: none; font: 600 12px/1 var(--mono); }
.jump-btn span { font-size: 12px; color: var(--ink-2); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.caret { flex: none; width: 0; height: 0; border: 4px solid transparent; border-top-color: var(--ink-3); margin-top: 4px; }
.jump-menu {
  position: absolute; top: 32px; left: 0; z-index: 30; width: 340px; max-height: 62vh; overflow-y: auto;
  background: #fff; border: 1px solid var(--line-2); border-radius: var(--r); box-shadow: var(--shadow-3); padding: 5px;
}
.jump-chapter {
  padding: 8px 8px 4px; font: 500 10px/1 var(--sans); letter-spacing: .09em;
  text-transform: uppercase; color: var(--ink-3);
}
.jump-row {
  display: grid; grid-template-columns: 34px 1fr auto; gap: 7px; align-items: center;
  width: 100%; padding: 5px 8px; border: 0; background: none; cursor: pointer;
  border-radius: var(--r-s); text-align: left;
}
.jump-row:hover { background: var(--paper-2); }
.jump-row b { font: 600 11.5px/1 var(--mono); }
.jump-name { font-size: 12px; color: var(--ink-2); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.jump-count { font: 400 10px/1 var(--mono); color: var(--ink-3); }
.jump-track { grid-column: 2 / -1; }

.chips-row { display: flex; gap: 4px; overflow-x: auto; flex: 1; scrollbar-width: thin; padding-bottom: 1px; }
.chip-q {
  display: inline-flex; align-items: center; gap: 5px; flex: none;
  height: 24px; padding: 0 8px 0 6px;
  font: 500 11.5px/1 var(--mono); color: var(--ink-2);
  background: #fff; border: 1px solid var(--line); border-radius: 99px; cursor: pointer;
  transition: border-color .12s, color .12s, box-shadow .12s;
}
.chip-q:hover { border-color: var(--ink-3); color: var(--ink); }
.chip-q.on { border-color: var(--ink); color: var(--ink); box-shadow: 0 0 0 2px rgba(23,21,15,.09); }
.chip-q .pip { width: 8px; height: 8px; border-radius: 50%; border: 1.5px solid var(--todo); }
.chip-q .pip:hover { box-shadow: 0 0 0 3px rgba(23,21,15,.1); }
.chip-q.is-todo .pip { border-color: var(--todo); }
.chip-q.is-doing .pip { border-color: var(--doing); background: linear-gradient(90deg, var(--doing) 50%, transparent 50%); }
.chip-q.is-done .pip { border-color: var(--done); background: var(--done); }
.chip-q.is-stuck .pip { border-color: var(--stuck); background: var(--stuck); }
.sheet-count { flex: none; font: 400 11px/1 var(--mono); color: var(--ink-3); }

/* ------------------------------------------------------------- paper */
.paper-scroll { flex: 1; overflow-y: auto; background: var(--paper); padding: 0 0 96px; }
.paper { width: 100%; background: var(--sheet); padding: 0 0 24px; }

.pg-head {
  position: sticky; top: 0; z-index: 4;
  display: flex; align-items: baseline; gap: 9px; padding: 10px 16px 7px 18px;
  background: linear-gradient(var(--sheet) 72%, rgba(255,255,255,0));
  border-bottom: 1.5px solid var(--ink); margin: 0 0 6px;
}
.pg-head b { flex: none; font: 600 13px/1 var(--mono); }
.pg-head span { font: 400 14px/1.2 var(--serif); color: var(--ink-2); }

.q { display: grid; grid-template-columns: 52px 1fr; align-items: stretch;
  padding: 0 14px 0 0; border-bottom: 1px solid var(--line); }
.q.current { background: linear-gradient(90deg, rgba(240,227,189,.30), rgba(240,227,189,.06) 60%, transparent); }
.q:last-child { border-bottom: 0; }
.q-margin {
  display: flex; flex-direction: column; align-items: center; gap: 4px;
  padding: 9px 9px 8px 0; border-right: 1px solid var(--line);
}
.q-num { font: 600 14px/1 var(--serif); color: var(--ink); }
.pin { width: 10px; height: 10px; padding: 0; border-radius: 50%; cursor: pointer;
  border: 1.5px solid var(--todo); background: transparent; transition: box-shadow .12s; }
.pin:hover { box-shadow: 0 0 0 3px rgba(23,21,15,.1); }
.pin.is-todo { border-color: var(--todo); }
.pin.is-doing { border-color: var(--doing); background: linear-gradient(90deg, var(--doing) 50%, transparent 50%); }
.pin.is-done { border-color: var(--done); background: var(--done); }
.pin.is-stuck { border-color: var(--stuck); background: var(--stuck); }
.q-page {
  font: 400 8.5px/1 var(--sans); letter-spacing: .05em; text-transform: uppercase;
  color: var(--ink-3); background: none; border: 0; cursor: pointer; opacity: 0; transition: opacity .12s;
}
.q:hover .q-page { opacity: 1; }
.q-page:hover { color: var(--ink); }
.q-body { padding: 6px 0 8px 14px; min-height: 44px; cursor: text; }

/* lines run together as one piece of writing: no boxes, no rules between
   them, just a bar in the gutter marking the line you are on */
.ln {
  position: relative; display: grid; grid-template-columns: 1fr; align-items: center;
  min-height: 28px; padding: 1px 22px 1px 8px; border-radius: 3px;
}
.ln::before {
  content: ""; position: absolute; left: 0; top: 3px; bottom: 3px; width: 2px;
  border-radius: 1px; background: transparent; transition: background .12s;
}
.ln:hover::before { background: var(--line-2); }
.ln.on::before, .ln:focus-within::before { background: var(--ink); }
.ln.has-aside { grid-template-columns: minmax(0, 1fr) 34%; column-gap: 14px; }
.ln-main { min-width: 0; }
.ln-aside {
  min-width: 0; padding: 2px 0 2px 12px; outline: none;
  border-left: 1px solid var(--line);
  font: 400 12px/1.5 var(--serif); color: var(--ink-3);
}
.ln-aside:empty::before { content: attr(data-placeholder); color: var(--line-2); }
.ln-aside:focus { color: var(--ink-2); border-left-color: var(--ink-3); }
.ln-split {
  position: absolute; right: 2px; top: 50%; transform: translateY(-50%);
  width: 16px; height: 18px; padding: 0; border: 0; border-radius: 3px;
  font: 500 11px/1 var(--mono); color: var(--ink-3);
  background: transparent; cursor: pointer; opacity: 0; transition: opacity .12s;
}
.ln:hover .ln-split, .ln:focus-within .ln-split { opacity: 1; }
.ln-split:hover { color: var(--ink); background: var(--paper-3); }
.ln.has-aside .ln-split { display: none; }
.ln.is-text .ln-main, .prose { font: 400 13.5px/1.6 var(--serif); color: var(--ink-2); }
.prose { outline: none; min-height: 22px; }
.prose:empty::before { content: "note"; color: var(--line-2); }
math-field {
  flex: 1; font-size: 16px; outline: none;
  /* the element ships with its own frame; the ruled line is our frame */
  border: 0; border-radius: 0; background: transparent; padding: 0 2px;
  --caret-color: var(--ink);
  --selection-background-color: #f0e3bd;
  --contains-highlight-background-color: transparent;
}
math-field::part(virtual-keyboard-toggle), math-field::part(menu-toggle) { display: none; }
.ln:focus-within { background: #fffdf6; }

/* -------------------------------------------------------------- dock */
.dock { flex: none; display: flex; flex-direction: column;
  border-top: 1px solid var(--line-2); background: var(--paper-2); }
#workspace[data-kbd="off"] .dock-slot { display: none; }
.dock-grip { height: 11px; display: grid; place-items: center; background: var(--paper-2); border: 0; cursor: pointer; }
.dock-grip span { width: 34px; height: 3px; border-radius: 2px; background: var(--line-2); display: block; }
.dock-grip:hover span { background: var(--ink-3); }
.dock-slot { height: var(--dock); min-height: 186px; max-height: 40vh; overflow: hidden; position: relative; }
.dock-slot .ML__keyboard { position: absolute !important; inset: 0 !important; }

#kbdDock {
  --keyboard-background: var(--paper);
  --keyboard-border: var(--line);
  --keyboard-horizontal-rule: var(--line);
  --keyboard-padding-top: 2px;
  --keyboard-padding-bottom: 4px;
  --keyboard-padding-horizontal: 8px;
  --keyboard-toolbar-background: var(--paper);
  --keyboard-toolbar-background-hover: var(--paper-3);
  --keyboard-toolbar-background-selected: transparent;
  --keyboard-toolbar-text: var(--ink-3);
  --keyboard-toolbar-text-active: var(--ink);
  --keyboard-toolbar-font-size: 12px;
  --keycap-background: #fff;
  --keycap-background-hover: #fff;
  --keycap-background-active: var(--ink);
  --keycap-background-pressed: var(--paper-3);
  --keycap-border: var(--line);
  --keycap-border-bottom: var(--line-2);
  --keycap-text: var(--ink);
  --keycap-text-hover: var(--ink);
  --keycap-secondary-background: var(--paper-3);
  --keycap-secondary-background-hover: var(--paper-2);
  --keycap-secondary-text: var(--ink-2);
  --keycap-secondary-border: var(--line);
  --keycap-secondary-border-bottom: var(--line-2);
  --keycap-primary-background: var(--ink);
  --keycap-primary-text: var(--paper);
  --keycap-height: 38px;
  --keycap-gap: 4px;
  --keycap-font-size: 15px;
  --keycap-shift-color: var(--ink-3);
}

/* --------------------------------------------------------------- rail */
.rail {
  flex: 0 0 var(--rail); display: flex; flex-direction: column;
  border-left: 1px solid var(--line); background: var(--paper-2);
}
.rail-spine { flex: 1; display: flex; flex-direction: column; gap: 3px; padding: 8px 6px; overflow: hidden; }
.tick {
  flex: 1; display: flex; align-items: center; gap: 5px; min-height: 22px;
  padding: 0 2px; border: 0; background: none; cursor: pointer; border-radius: 3px;
}
.tick:hover { background: var(--paper-3); }
.tick-bar {
  width: 4px; align-self: stretch; margin: 2px 0; border-radius: 2px;
  background: var(--line); display: flex; flex-direction: column; overflow: hidden;
}
.tick-bar .seg { width: 100%; }
.tick-n { font: 600 10px/1 var(--mono); color: var(--ink-3); }
.tick:hover .tick-n { color: var(--ink); }
.rail-foot { display: grid; gap: 4px; padding: 8px 7px; border-top: 1px solid var(--line); }
.rail-ic {
  width: 32px; height: 32px; display: grid; place-items: center;
  font: 600 11px/1 var(--mono); color: var(--ink-2);
  background: #fff; border: 1px solid var(--line); border-radius: 50%; cursor: pointer;
  transition: border-color .12s, color .12s;
}
.rail-ic:hover { border-color: var(--ink); color: var(--ink); }
#railSettings { font-size: 14px; }

.rail-panel {
  position: absolute; top: 0; right: var(--rail); bottom: 0; width: 288px; z-index: 20;
  display: flex; flex-direction: column;
  background: var(--paper); border-left: 1px solid var(--line-2);
  box-shadow: -14px 0 34px -22px rgba(23,21,15,.6);
}
.rail-panel-head {
  display: flex; align-items: center; gap: 8px; padding: 9px 8px 9px 14px;
  border-bottom: 1px solid var(--line); background: var(--paper-2);
}
.rail-panel-head b { font: 500 12.5px/1 var(--sans); }
.rail-panel-head span { font: 400 10.5px/1 var(--mono); color: var(--ink-3); }
.rail-panel-head .icon { margin-left: auto; }
.rail-tree { flex: 1; overflow-y: auto; padding: 4px 0 30px; }

.tchap { border-bottom: 1px solid var(--line); }
.tchap > summary {
  display: flex; align-items: center; gap: 7px; padding: 8px 12px 5px;
  cursor: pointer; list-style: none;
}
.tchap > summary::-webkit-details-marker { display: none; }
.tchap > summary:hover { background: var(--paper-2); }
.tw { width: 0; height: 0; border: 4px solid transparent; border-left-color: var(--ink-3);
  transition: transform .15s; transform-origin: 25% 50%; flex: none; }
.tchap[open] .tw { transform: rotate(90deg); }
.tchap > summary b { flex: none; font: 600 11.5px/1 var(--mono); }
.tchap > summary span { flex: 1; font-size: 11.5px; color: var(--ink-2);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tchap > summary em { font: 400 10px/1 var(--mono); font-style: normal; color: var(--ink-3); }
.tchap-track { margin: 0 12px 6px; }

.tsec { padding: 0 12px 8px 20px; }
.tsec-head { display: flex; align-items: baseline; gap: 6px; width: 100%;
  padding: 3px 4px; border: 0; background: none; cursor: pointer; text-align: left;
  border-radius: var(--r-s); color: var(--ink); }
.tsec-head:hover { background: var(--paper-2); }
.tsec-head b { flex: none; font: 600 11px/1 var(--mono); }
.tsec-head span { flex: 1; font-size: 11px; color: var(--ink-2);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.tsec-head em { font: 400 9.5px/1 var(--mono); font-style: normal; color: var(--ink-3); }
.tsec-track { margin: 2px 4px 5px; }
.tpins { display: flex; flex-wrap: wrap; gap: 3px; padding-left: 4px; }
.tp {
  min-width: 22px; height: 19px; padding: 0 4px;
  font: 500 10px/1 var(--mono); color: var(--ink-2);
  background: #fff; border: 1px solid var(--line); border-radius: 3px; cursor: pointer;
  border-left-width: 3px;
}
.tp:hover { border-color: var(--ink-3); color: var(--ink); }
.tp.is-todo { border-left-color: var(--todo); }
.tp.is-doing { border-left-color: var(--doing); }
.tp.is-done { border-left-color: var(--done); background: #f1f8f3; }
.tp.is-stuck { border-left-color: var(--stuck); background: #fdf2f2; }

/* ------------------------------------------------------- zoom + loupe */
.zoomer {
  position: absolute; right: 14px; bottom: 12px; z-index: 12;
  display: flex; align-items: center; gap: 1px; padding: 3px;
  background: rgba(250,248,244,.9); backdrop-filter: blur(8px);
  border: 1px solid var(--line-2); border-radius: 99px; box-shadow: var(--shadow-1);
  opacity: .5; transition: opacity .16s;
}
.pane-book:hover .zoomer { opacity: 1; }
.zoomer button {
  height: 22px; min-width: 24px; padding: 0 7px; border: 0; border-radius: 99px;
  font: 500 11px/1 var(--mono); color: var(--ink-2); background: transparent; cursor: pointer;
}
.zoomer button:hover { background: var(--paper-3); color: var(--ink); }

.loupe {
  position: fixed; z-index: 70; padding: 6px; pointer-events: none;
  background: #fff; border: 1px solid var(--line-2); border-radius: var(--r);
  box-shadow: var(--shadow-3);
  opacity: 0; transform: scale(.985); transition: opacity .12s, transform .12s;
}
.loupe.in { opacity: 1; transform: none; }
.loupe canvas { display: block; border-radius: 3px; }
.loupe-tag {
  display: block; padding: 0 2px 5px;
  font: 500 9.5px/1 var(--mono); letter-spacing: .05em; color: var(--ink-3);
}

/* ------------------------------------------------------------ picker */
.picker { position: fixed; z-index: 60; display: grid; padding: 4px; background: #fff;
  border: 1px solid var(--line-2); border-radius: var(--r); box-shadow: var(--shadow-2); }
.picker button { display: flex; align-items: center; gap: 8px; padding: 6px 12px 6px 8px;
  font: 400 12px/1 var(--sans); color: var(--ink); background: none; border: 0;
  border-radius: var(--r-s); cursor: pointer; text-align: left; }
.picker button:hover { background: var(--paper-2); }

/* -------------------------------------------------------------- boot */
.boot { position: absolute; inset: 0; display: grid; place-items: center; background: var(--paper); z-index: 30; }
.boot p { font: 400 13px/1 var(--sans); color: var(--ink-2); }

/* ----------------------------------------------------------- dialogs */
dialog { width: min(880px, 94vw); max-height: 88vh; padding: 0; border: 0; border-radius: 12px;
  background: var(--paper); color: var(--ink); box-shadow: var(--shadow-3); }
dialog#exportDlg { width: min(620px, 94vw); }
dialog::backdrop { background: rgba(23, 21, 15, .38); backdrop-filter: blur(2px); }
.dlg-head { display: flex; align-items: center; gap: 16px; padding: 14px 18px;
  border-bottom: 1px solid var(--line-2); background: var(--paper-2); border-radius: 12px 12px 0 0; }
.dlg-head h2 { margin: 0; font: 400 17px/1 var(--serif); }
.tabs { display: flex; gap: 2px; margin-left: auto; }
.tab { height: 28px; padding: 0 13px; border: 0; border-radius: var(--r);
  font: 500 12.5px/1 var(--sans); color: var(--ink-2); background: transparent; cursor: pointer; }
.tab:hover { background: var(--paper-3); color: var(--ink); }
.tab.on { background: var(--ink); color: var(--paper); }
.panel { padding: 18px; overflow-y: auto; max-height: calc(88vh - 60px); }
.panel h3 { margin: 0 0 8px; font: 500 13px/1 var(--sans); }
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 22px; margin-top: 18px; }
.split .btn { margin-top: 8px; }
.grid2 { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.fieldset { display: grid; gap: 5px; }
.fieldset > span { font: 500 10.5px/1 var(--sans); letter-spacing: .08em; text-transform: uppercase; color: var(--ink-3); }
.rowbtns { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; margin-top: 14px; }
.rowbtns.end { justify-content: flex-end; }

.plist { display: grid; gap: 6px; }
.prow { display: flex; align-items: center; gap: 12px; padding: 10px 12px; background: #fff;
  border: 1px solid var(--line); border-radius: var(--r); }
.prow.on { border-color: var(--ink-3); box-shadow: 0 0 0 3px rgba(23,21,15,.06); }
.prow b { display: block; font: 500 13px/1.3 var(--sans); }
.prow small { display: block; font: 400 11px/1.4 var(--mono); color: var(--ink-3); }
.prow-acts { display: flex; gap: 4px; margin-left: auto; }
.prow-acts .btn { height: 26px; padding: 0 9px; font-size: 11.5px; }

.blist { display: grid; gap: 6px; }
.brow { display: flex; align-items: center; gap: 16px; padding: 9px 12px; background: #fff;
  border: 1px solid var(--line); border-radius: var(--r); }
.brow b { font: 500 12.5px/1.3 var(--sans); }
.brow small { display: block; font-size: 11px; color: var(--ink-3); }
.chips { display: flex; flex-wrap: wrap; gap: 4px; margin-left: auto; }
.chip { display: inline-flex; align-items: center; gap: 5px; height: 26px; padding: 0 10px;
  font: 500 11.5px/1 var(--sans); color: var(--ink-2); background: var(--paper-2);
  border: 1px solid var(--line); border-radius: 99px; cursor: pointer; }
.chip:hover { border-color: var(--ink-3); color: var(--ink); }
.chip.on { background: var(--ink); border-color: var(--ink); color: var(--paper); }
.chip i { font: 600 9.5px/1 var(--mono); font-style: normal; padding: 2px 4px;
  border-radius: 99px; background: rgba(250,248,244,.24); }

/* -------------------------------------------------------- print view */
#printView { position: absolute; left: -10000px; top: 0; width: 190mm; background: #fff; color: #000; }
.pv-head { border-bottom: 2px solid #000; padding-bottom: 8px; margin-bottom: 18px; }
.pv-head h1 { margin: 0; font: 400 22px/1.2 var(--serif); }
.pv-head p { margin: 4px 0 0; font: 400 11px/1 var(--sans); color: #555; }
.pv-sec { margin: 22px 0 10px; padding-bottom: 5px; border-bottom: 1px solid #999;
  font: 400 15px/1.2 var(--serif); break-after: avoid; }
.pv-sec b { font-family: var(--mono); font-size: 13px; margin-right: 8px; }
.pv-q { display: grid; grid-template-columns: 46px 1fr; gap: 10px; margin: 0 0 12px; break-inside: avoid; }
.pv-n { font: 600 14px/1.4 var(--serif); }
.pv-n i { display: block; font: 400 8.5px/1.4 var(--sans); font-style: normal;
  text-transform: uppercase; letter-spacing: .06em; color: #888; }
.pv-body { border-left: 1px solid #ddd; padding-left: 12px; }
.pv-math { margin: 3px 0; font-size: 15px; }
.pv-text { margin: 3px 0; font: 400 12.5px/1.55 var(--serif); }

@media print {
  body { overflow: visible; background: #fff; }
  body[data-printing] > *:not(#printView) { display: none !important; }
  #printView { position: static !important; left: auto !important; width: auto; }
  @page { margin: 16mm 14mm; }
}

/* -------------------------------------------------------- responsive */
@media (max-width: 1200px) { .jump-btn { max-width: 160px; } }
@media (max-width: 980px) {
  #workspace { flex-direction: column; }
  .rail-panel { width: 262px; }
  .pane-book { flex: 0 0 42vh; order: 1 !important; }
  .pane-sheet { flex: 1 1 0; order: 3 !important; }
  .splitter { display: none; }
  .hud { bottom: 10px; left: 10px; }
  .hud-progress { display: none; }
  .dock-slot { min-height: 168px; max-height: 40vh; }
}
@media (max-width: 620px) {
  .jump-btn span { display: none; }
  :root { --rail: 38px; }
  .rail-panel { width: calc(100vw - var(--rail)); }
  .ln.has-aside { grid-template-columns: 1fr; row-gap: 2px; }
  .ln-aside { border-left: 0; padding-left: 0; border-top: 1px solid var(--line); }
  .q { grid-template-columns: 40px 1fr; padding-right: 8px; }
  .split, .grid2 { grid-template-columns: 1fr; }
}