/* TeachMeSheets brand. House style shared with investadaily and Variant
   Sudoku: white page, ink type, 2px ink cards, pill buttons, condensed
   display headlines, one pastel per course section. The practice window
   alone borrows Google Sheets chrome (see learn.css). */
@import url("https://fonts.googleapis.com/css2?family=Bricolage+Grotesque:opsz,wdth,wght@12..96,75..100,400;12..96,75..100,600;12..96,75..100,800&family=Plus+Jakarta+Sans:wght@400;500;600;700&family=Newsreader:ital,opsz,wght@0,6..72,400;0,6..72,500;1,6..72,400&family=JetBrains+Mono:wght@400;500;600&display=swap");

:root {
  color-scheme: light;
  --bg: #ffffff;
  --ink: #111111;
  --muted: #55595c;
  --hair: #e2e4e3;
  --soft: #f4f6f4;

  /* Section colors, in rotation order. Identity only, never a signal. */
  --mint: #d6efd9;
  --apricot: #ffd7ba;
  --sky: #c4e4fa;
  --butter: #f8e8a9;
  --lilac: #eed5f4;
  --seafoam: #bbece9;
  --orchid: #ffd0e1;

  --ok: #0a7f45;
  --ok-soft: #e3f4e9;
  --bad: #c42f2a;
  --bad-soft: #fbe6e4;
  --hint-soft: #fdf3d0;

  --f-display: "Bricolage Grotesque", "Arial Narrow", Arial, sans-serif;
  --f-ui: "Plus Jakarta Sans", Arial, sans-serif;
  --f-read: "Newsreader", Georgia, serif;
  --f-mono: "JetBrains Mono", ui-monospace, Menlo, monospace;

  --r-panel: 28px;
  --r-card: 20px;
  --r-node: 12px;
}

* { box-sizing: border-box; }
[hidden] { display: none !important; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.55 var(--f-ui);
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; }
h1, h2, h3 {
  text-wrap: balance;
  font-family: var(--f-display);
  font-weight: 800;
  font-stretch: 78%;
  letter-spacing: -0.02em;
  line-height: 0.95;
}
p, li { text-wrap: pretty; }
code, kbd {
  font: 500 0.88em var(--f-mono);
  background: var(--soft);
  border: 1px solid var(--hair);
  padding: 1px 6px;
  border-radius: 6px;
}

/* Logo: an active spreadsheet cell, fill handle and all. */
.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  text-decoration: none;
  font: 400 26px/1 var(--f-display);
  font-stretch: 75%;
  letter-spacing: -0.02em;
}
.logo b { font-weight: 800; }
.logo-mark { width: 32px; height: 32px; flex: none; }

/* Buttons: pills, the one tactile thing on the page. */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 2px solid var(--ink);
  background: var(--bg);
  color: var(--ink);
  font: 600 15px var(--f-ui);
  padding: 9px 20px;
  border-radius: 999px;
  cursor: pointer;
  text-decoration: none;
  white-space: nowrap;
  box-shadow: 0 3px 0 var(--ink);
  transition: transform 0.08s ease, box-shadow 0.08s ease;
}
.btn:hover { transform: translateY(-1px); box-shadow: 0 4px 0 var(--ink); }
.btn:active { transform: translateY(3px); box-shadow: 0 0 0 var(--ink); }
.btn.primary { background: var(--ink); color: #fff; }
.btn.quiet { border-color: transparent; box-shadow: none; color: var(--muted); }
.btn.quiet:hover { color: var(--ink); transform: none; }
.btn.lg { padding: 13px 28px; font-size: 16px; }
.btn:disabled { opacity: 0.4; cursor: default; transform: none; box-shadow: none; }

/* Progress */
.bar { height: 8px; border-radius: 999px; background: var(--soft); border: 1px solid var(--hair); overflow: hidden; }
.bar > span { display: block; height: 100%; background: var(--ink); border-radius: 999px; transition: width 0.3s ease; }

.type-icon { width: 18px; height: 18px; flex: none; color: var(--muted); }

/* Status: an empty cell that fills in ink when done. */
.status {
  width: 20px;
  height: 20px;
  flex: none;
  border-radius: 6px;
  border: 2px solid #b9bdbb;
  display: grid;
  place-items: center;
  background: var(--bg);
}
.status svg { width: 13px; height: 13px; display: none; }
.done .status { background: var(--ink); border-color: var(--ink); }
.done .status svg { display: block; }

/* Section color swatch */
.swatch { width: 14px; height: 14px; flex: none; border-radius: 4px; border: 1.5px solid var(--ink); }

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