/* shared by every Butterbricks page: tokens, the title bar, buttons and tabs, the three-pane layout, the editor, the
   account box, and the pixel-art layer at the end. Each track's style.css adds what only it uses */

:root {
  /* white and gold, like butter on a plate */
  --page: #fbf7ec;
  --bg: #ffffff;
  --cell: #fffdf7;
  --chrome: #fcf4dc;
  --chrome-2: #f7e7b8;
  --line: #ede0b8;
  --line-strong: #d6be7c;
  --text: #2d2314;
  --muted: #7c6a45;
  --dark: #3b2d13;
  --soft: #faf0d2;
  --gold: #e3ad32;
  --gold-light: #f4cd5c;
  --gold-deep: #a8741a;
  --done: #2e7d4a;
  --done-bg: #e3f2e2;
  --bad: #b3261e;
  --bad-bg: #fbe6e2;
  --warn: #8a5a00;
  --warn-bg: #fdf0d2;
  --butter: #f6cd57;
  --butter-soft: #fff4cf;
  --butter-deep: #8a5a12;
  --mono: "JetBrains Mono", Menlo, Consolas, "Cascadia Mono", monospace;
  --ui: "Segoe UI", system-ui, -apple-system, sans-serif;
  --pixel: "Times New Roman", Tinos, Times, serif;  /* pixelated by the #px-text filter in common.js */
  --edge: #8a5a12;         /* the dark outline pixel frames are drawn with */
  --left-w: 42%;
  --results-h: 36vh;
  /* tiles drawn pixel by pixel by tools/pixelart.py, shown at 2x with no smoothing, so their pixels match the
     2px pixels of the text */
  --tex-parchment: 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  --tex-cream: 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}

* { box-sizing: border-box; }
html, body { height: 100%; margin: 0; }

body {
  background: var(--page);
  color: var(--text);
  font: 15.5px/1.5 var(--ui);
  display: grid;
  grid-template-rows: 50px 1fr;
  overflow: hidden;
}

button { font: inherit; }
code, pre, textarea { font-family: var(--mono); }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.spacer { flex: 1; }
[hidden] { display: none !important; }

/* buttons and tabs */

.btn {
  border: 1px solid var(--line-strong);
  background: var(--bg);
  color: var(--text);
  padding: 4px 13px;
  border-radius: 3px;
  cursor: pointer;
  white-space: nowrap;
  text-decoration: none;
}
.btn:hover { background: var(--chrome-2); }
.btn:active { background: var(--line); }
.btn:disabled { color: #b5a98c; border-color: var(--line); background: var(--bg); cursor: default; }
.btn.primary { background: linear-gradient(#f6cf5f, var(--gold)); border-color: var(--gold-deep); color: #2b1d05; font-weight: 700; box-shadow: inset 0 1px 0 rgba(255, 255, 255, .5); }
.btn.primary:hover { background: linear-gradient(#f9d977, #eab83f); }
.btn.primary:disabled { background: #efe3c2; border-color: #dccb9a; color: #a8986f; box-shadow: none; }
.btn.ghost { border-color: transparent; background: transparent; }
.btn.ghost:hover { background: var(--chrome-2); border-color: var(--line); }
.btn.small { padding: 1px 8px; font-size: 13px; }
.btn.danger { border-color: var(--bad); color: var(--bad); }

.tabs {
  display: flex;
  gap: 2px;
  padding: 0 10px;
  border-bottom: 1px solid var(--line-strong);
  background: var(--chrome);
  flex: none;
}
.tab {
  border: 1px solid transparent;
  border-bottom: 0;
  background: transparent;
  padding: 6px 14px 5px;
  margin-bottom: -1px;
  cursor: pointer;
  color: var(--muted);
  border-radius: 3px 3px 0 0;
}
.tab:hover { color: var(--text); }
.tab.on { background: var(--bg); border-color: var(--line-strong); color: var(--text); font-weight: 600; box-shadow: inset 0 2px 0 var(--gold); }

.chip { border: 1px solid var(--line-strong); background: var(--chrome); padding: 0 9px; border-radius: 10px; white-space: nowrap; }
.chip.easy { color: var(--done); border-color: #a8d4b6; background: var(--done-bg); }
.chip.medium { color: var(--warn); border-color: #e6cb8e; background: var(--warn-bg); }
.chip.hard { color: var(--bad); border-color: #e7aaa5; background: var(--bad-bg); }
.meta { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; margin-top: 6px; font-size: 13px; color: var(--muted); }

/* title bar */

.titlebar {
  display: flex;
  align-items: center;
  gap: 20px;
  padding: 0 14px;
  border-bottom: 2px solid var(--gold-light);
  background: var(--bg);
  min-width: 0;
}
.brand { font-weight: 800; font-size: 19px; display: flex; align-items: center; gap: 8px; color: var(--text); text-decoration: none; letter-spacing: -.01em; }
.brand .logo { width: 28px; height: 28px; display: block; }
.progress { display: flex; align-items: center; gap: 10px; color: var(--muted); font-weight: 600; font-size: 14px; white-space: nowrap; }
.progress-track { width: 180px; height: 11px; border-radius: 6px; background: var(--chrome-2); border: 1px solid var(--line); overflow: hidden; }
.progress-fill { height: 100%; width: 0; background: var(--butter); box-shadow: inset 0 -2px 0 #e0ad35; transition: width .3s; }
.titlebar-actions { margin-left: auto; display: flex; gap: 6px; align-items: center; }

/* layout: sidebar | statement | splitter | editor over results */

.app {
  display: grid;
  grid-template-columns: 250px var(--left-w) 6px 1fr;
  min-height: 0;
}
.vsplit, .hsplit { background: var(--chrome-2); flex: none; }
.vsplit { cursor: col-resize; border-left: 1px solid var(--line); border-right: 1px solid var(--line); }
.hsplit { cursor: row-resize; height: 6px; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.vsplit:hover, .hsplit:hover, .dragging { background: var(--line); }

.sidebar {
  border-right: 1px solid var(--line-strong);
  background: var(--chrome);
  overflow-y: auto;
}
.sidebar h2 {
  margin: 0;
  padding: 10px 12px 6px;
  font-size: 12.5px;
  text-transform: uppercase;
  letter-spacing: .05em;
  color: var(--muted);
  border-bottom: 1px solid var(--line);
}

/* the problem list: categories, their groups (SQL's levels), and problems */

.cat-head {
  display: flex; align-items: center; gap: 8px; width: 100%;
  padding: 9px 12px 8px 8px; border: 0; border-bottom: 2px solid var(--line-strong);
  background: var(--chrome-2); color: var(--text); text-align: left; cursor: pointer;
  font: 700 16px var(--pixel); position: sticky; top: 0; z-index: 2;
}
.cat-head:hover { background: #f4dc95; }
.cat-head.here { background: var(--gold-light); }
.cat-head .caret { width: 12px; color: var(--gold-deep); }
.cat-head .cat-title { flex: 1; }
.cat-head .cat-count { font-size: 13px; color: var(--muted); }
.group-head {
  display: flex; justify-content: space-between; gap: 8px; margin: 0;
  padding: 8px 12px 4px 26px; font: 600 12.5px var(--pixel); letter-spacing: .05em; text-transform: uppercase;
  color: var(--gold-deep); border-bottom: 1px solid var(--line);
}

/* SQL challenges in the list */

.challenge-link {
  display: flex;
  gap: 8px;
  align-items: baseline;
  width: 100%;
  border: 0;
  border-left: 4px solid transparent;
  background: transparent;
  text-align: left;
  padding: 4px 10px 4px 8px;
  cursor: pointer;
  color: var(--text);
  font-size: 14.5px;
}
.challenge-link:hover { background: var(--chrome-2); }
.challenge-link .num { color: var(--muted); width: 22px; text-align: right; flex: none; font-variant-numeric: tabular-nums; }
.challenge-link .mark { width: 14px; flex: none; text-align: center; color: var(--line-strong); }
.challenge-link.solved { color: var(--done); }
.challenge-link.solved .mark, .challenge-link.solved .num { color: var(--done); font-weight: 700; }
.challenge-link.current { border-left-color: var(--gold); background: var(--bg); font-weight: 700; }

/* implementation problems in the list */

.problem-link {
  display: block;
  width: 100%;
  border: 0;
  border-left: 4px solid transparent;
  border-bottom: 1px solid var(--line);
  background: transparent;
  text-align: left;
  padding: 9px 12px 9px 10px;
  cursor: pointer;
  color: var(--text);
}
.problem-link:hover { background: var(--chrome-2); }
.problem-link.current { border-left-color: var(--gold); background: var(--bg); }
.problem-link .name { font-weight: 700; display: block; }
.problem-link .sub { font-size: 13px; color: var(--muted); display: block; margin-top: 1px; }
.pips { display: flex; gap: 3px; margin-top: 6px; }
.pip { width: 26px; height: 6px; border-radius: 3px; background: var(--line); }
.pip.done { background: var(--done); }
.problem-link.complete .name::after { content: " ✓"; color: var(--done); }


.statement-pane { display: flex; flex-direction: column; min-width: 0; min-height: 0; background: var(--bg); }
.left-body { overflow-y: auto; padding: 16px 22px 40px; flex: 1; min-height: 0; }
.left-body h1 { margin: 0; font-size: 25px; }
.left-body h2 { font-size: 19px; margin: 0 0 6px; }
.left-body code { background: var(--chrome); border: 1px solid var(--line); padding: 0 4px; border-radius: 3px; font-size: 13.5px; }
.left-body pre {
  background: var(--cell);
  border: 1px solid var(--line);
  border-left: 3px solid var(--line-strong);
  padding: 9px 12px;
  overflow-x: auto;
  font-size: 13.5px;
  line-height: 1.45;
}
.left-body pre code { background: none; border: 0; padding: 0; font-size: inherit; }
.hint-box { margin-top: 16px; }
.hint { margin: 8px 0; padding: 8px 12px; border: 1px solid #ecd28f; border-left: 4px solid var(--gold); background: var(--butter-soft); }

.code-pane { display: flex; flex-direction: column; min-width: 0; min-height: 0; }
.editor-bar, .run-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 10px;
  background: var(--chrome);
  flex: none;
}
.editor-bar { border-bottom: 1px solid var(--line); }
.run-bar { border-top: 1px solid var(--line); }
.editor-label { font: 600 14px var(--mono); }
.editor { flex: 1; min-height: 100px; position: relative; }
.editor .CodeMirror { position: absolute; inset: 0; height: auto; font: 14px/1.5 var(--mono); background: var(--cell); }
.CodeMirror-gutters { background: var(--chrome); border-right: 1px solid var(--line); }
.CodeMirror-activeline-background { background: #fdf5dc; }
.CodeMirror-selected, .CodeMirror-focused .CodeMirror-selected { background: #f8e3a6; }
.CodeMirror-cursor { border-left-color: var(--dark); }
.CodeMirror-linenumber { color: #b3a27a; }
.results-pane { height: var(--results-h); flex: none; display: flex; flex-direction: column; min-height: 0; background: var(--bg); }

/* syntax colors for highlighted code outside the editor (CodeMirror runmode) */
.cm-keyword { color: #7a2d8c; }
.cm-def { color: #1f4fa3; }
.cm-string { color: #2f6f1f; }
.cm-number { color: #a3551f; }
.cm-comment { color: #7d8288; font-style: italic; }
.cm-builtin, .cm-variable-2 { color: #0b6b78; }

/* a correct answer: green flash and confetti */

@keyframes flash-green {
  0%   { background: #7fd49a; }
  100% { background: var(--done-bg); }
}
@keyframes flash-green-editor {
  0%   { box-shadow: inset 0 0 0 3px var(--done), 0 0 18px #5cc47f; }
  100% { box-shadow: inset 0 0 0 3px transparent, 0 0 0 transparent; }
}
.flash { animation: flash-green 0.9s ease-out; }
.editor.flash { animation: flash-green-editor 0.9s ease-out; z-index: 1; }
#confetti { position: fixed; inset: 0; width: 100%; height: 100%; pointer-events: none; z-index: 1000; }
@media (prefers-reduced-motion: reduce) {
  .flash, .editor.flash { animation: none; }
}

@media (max-width: 1100px) {
  .app { grid-template-columns: 200px var(--left-w) 6px 1fr; }
  .progress-track { width: 100px; }
}

/* account: the header's sign-in button, and the sign-in box */

.account { display: flex; align-items: center; gap: 8px; margin-left: 10px; font-size: 14px; white-space: nowrap; }
.titlebar-actions + .account { margin-left: 6px; }
.titlebar > .account:only-of-type { margin-left: auto; }
.who { display: inline-block; color: var(--text); font-size: 16px; }
.who-icon { color: var(--done); font-size: 10px; vertical-align: 2px; }
.sync-state { font-size: 12px; color: var(--muted); }
.sync-state.offline { color: var(--warn); }

.modal-backdrop { position: fixed; inset: 0; z-index: 2000; display: grid; place-items: center; padding: 16px; background: rgba(70, 45, 8, .35); }
.modal { width: 100%; max-width: 360px; display: flex; flex-direction: column; gap: 10px; padding: 22px 24px 18px; }
.modal-head { display: flex; align-items: center; gap: 10px; }
.modal-head .logo { width: 47px; height: 40px; image-rendering: pixelated; }
.modal-tabs { display: flex; gap: 4px; }
.modal-tabs button { flex: 1; font: 600 15px var(--pixel); padding: 5px; border: 2px solid var(--line-strong); background: var(--chrome); color: var(--muted); cursor: pointer; }
.modal-tabs button.on { background: var(--gold-light); border-color: var(--edge); color: var(--text); }
.modal-reason { margin: 2px 0; padding: 8px 10px; background: var(--butter-soft); border: 2px solid var(--gold-light); font-size: 14px; }
.modal label { display: flex; flex-direction: column; gap: 3px; font-size: 16px; color: #5f4a1f; }
.modal input { font: 15px var(--ui); padding: 7px 9px; border: 2px solid var(--line-strong); background: var(--cell); color: var(--text); }
.modal input:focus { outline: none; border-color: var(--gold-deep); box-shadow: 0 0 0 2px var(--gold-light); }
.modal-error { color: var(--bad); font-size: 14px; padding: 6px 9px; background: var(--bad-bg); border: 2px solid #e7aaa5; }
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 4px; }
.modal-note { margin: 0; }

/* ---- the pixel-art layer: square corners, stepped frames, Times New Roman pixelated to a 2px grid for the chrome,
   and textures at the same 2px scale ---- */

*, *::before, *::after { border-radius: 0 !important; }
img.logo, .hero-logo { image-rendering: pixelated; }

body { background-color: var(--page); background-image: var(--tex-parchment); background-size: 64px 64px; image-rendering: auto; }
.titlebar { background: var(--tex-cream) 0 0 / 256px 32px; image-rendering: pixelated; border-bottom: 2px solid var(--edge); box-shadow: inset 0 -4px 0 var(--gold-light); }
.tabs, .editor-bar, .run-bar, .sheet-tabs { background-image: var(--tex-cream); background-size: 256px 32px; image-rendering: pixelated; }
.sidebar { border-right: 2px solid var(--line-strong); background: var(--chrome); }
.statement-pane, .results-pane { background: var(--bg); }
.vsplit, .hsplit { background: var(--line); }
.vsplit { border-left: 2px solid var(--line-strong); border-right: 2px solid var(--line-strong); }
.hsplit { border-top: 2px solid var(--line-strong); border-bottom: 2px solid var(--line-strong); }
.tabs { border-bottom: 2px solid var(--line-strong); }
.run-bar { border-top: 2px solid var(--line-strong); }
.editor-bar { border-bottom: 2px solid var(--line-strong); }

/* the chrome is set in Times and pixelated; problem text, code and data stay in fonts made for reading */
.btn, .tab, .chip, .sidebar h2, .progress, .left-body h1, .left-body h2, .editor-label, .results-summary,
.status .verdict, .sheet-tab, .part-chip, .problem-link .name, .timer, .py-status, .card h2, .cat-head, .group-head,
.who, .modal-tabs button, .modal label {
  font-family: var(--pixel);
  font-weight: 700;
  filter: url(#px-text);
}
.left-body h1 { font-size: 30px; }
.left-body h2 { font-size: 22px; }
.sidebar h2 { font-size: 15px; letter-spacing: 0; text-transform: none; color: #8f5f10; }
.editor-label { font-size: 16px; }
.cat-head { font-size: 18px; }
.cat-head .cat-count { font-size: 15px; color: #5f4a1f; }
.group-head { font-size: 15px; text-transform: none; letter-spacing: 0; color: #8f5f10; }
.problem-link .name { font-size: 16px; }

/* the name, in butter yellow with a bevel: a light edge above and left, shade and an outline below and right */
.brand { gap: 8px; }
.brand .logo { width: 44px; height: 37px; }
.wordmark {
  display: inline-block;
  font: 700 27px/1 var(--pixel);
  color: #f9cf45;
  letter-spacing: .01em;
  text-shadow: -1px -1px 0 #fff6c4, 1px 1px 0 #c98e1c, 2px 2px 0 #8a5a12, 3px 3px 0 #6b4510;
  padding: 3px 6px 6px 3px;
  filter: url(#px-crisp);
}

/* a raised pixel button: dark outline, light top-left bevel, shaded bottom-right, notched corners */
.btn {
  border: 2px solid var(--edge);
  background: var(--cell);
  font-size: 16px;
  padding: 3px 12px 4px;
  box-shadow: inset 2px 2px 0 #fff, inset -2px -2px 0 #ead9ab;
  clip-path: polygon(2px 0, calc(100% - 2px) 0, 100% 2px, 100% calc(100% - 2px), calc(100% - 2px) 100%, 2px 100%, 0 calc(100% - 2px), 0 2px);
}
.btn:hover { background: var(--butter-soft); }
.btn:active:not(:disabled) { transform: translateY(2px); box-shadow: inset 2px 2px 0 #ead9ab; }
.btn.primary { background: var(--gold-light); border-color: var(--edge); color: #2b1d05; box-shadow: inset 2px 2px 0 #fbe6a2, inset -2px -2px 0 #d39a28; }
.btn.primary:hover { background: #f8d76e; }
.btn.primary:disabled, .btn:disabled { background: #f3ead2; border-color: #cdbb8a; color: #ad9c70; box-shadow: none; }
.btn.ghost { border-color: transparent; background: transparent; box-shadow: none; clip-path: none; }
.btn.ghost:hover { background: rgba(255, 244, 207, .8); border-color: var(--line-strong); }
.btn.small { font-size: 15px; padding: 1px 8px 2px; }
.btn.danger { border-color: var(--bad); color: var(--bad); }

.tab { font-size: 16px; border-width: 2px; margin-bottom: -2px; }
.tab.on { border-color: var(--line-strong); box-shadow: inset 0 2px 0 var(--gold); }
.chip { border-width: 2px; font-size: 15px; color: #4a3a1c; }
.chip.medium { background: var(--butter-soft); }

/* a segmented pixel progress bar */
.progress { font-size: 16px; color: #5f4a1f; }
.progress-track { height: 14px; border: 2px solid var(--edge); background: #f3e4bb; padding: 2px; box-shadow: inset 2px 2px 0 #e3cf98; }
.progress-fill { background: repeating-linear-gradient(90deg, var(--gold-light) 0 4px, transparent 4px 6px); box-shadow: none; transition: width .3s steps(8); }

/* a framed parchment panel, for cards and the sign-in box */
.panel {
  background: var(--cell) var(--tex-parchment) 0 0 / 64px 64px;
  border: 2px solid var(--edge);
  box-shadow: inset 2px 2px 0 #fff, inset -2px -2px 0 #ecd9a6, 4px 4px 0 rgba(122, 78, 18, .22);
}

.hint { border-width: 2px; border-left-width: 6px; }
.CodeMirror-gutters { border-right: 2px solid var(--line); }