/* Light, clean theme for "The Secret Life of English Articles" */

:root {
  --bg: #fbf8f3;
  --ink: #1f2328;
  --muted: #6b6f76;
  --line: #d9d3c7;
  --card: #ffffff;

  /* colour-coding per article family */
  --indef: #2457c5;   /* a / an  */
  --def: #c2410c;     /* the     */
  --zero: #7c3aed;    /* Ø       */

  --right: #15803d;
  --wrong: #b91c1c;

  --font-body: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-head: "Fraunces", Georgia, serif;
  --font-ipa: "Noto Sans", "Charis SIL", "Doulos SIL", "Lucida Sans Unicode", sans-serif;
}

body,
.reveal-viewport {
  background: var(--bg);
}

.reveal {
  font-family: var(--font-body);
  font-size: 38px;
  font-weight: 400;
  color: var(--ink);
}

.reveal .slides section {
  text-align: left;
}

.reveal h1,
.reveal h2,
.reveal h3 {
  font-family: var(--font-head);
  font-weight: 600;
  color: var(--ink);
  line-height: 1.1;
  margin: 0 0 0.6em;
  letter-spacing: -0.01em;
}
.reveal h1 { font-size: 2.3em; }
.reveal h2 { font-size: 1.6em; }
.reveal h3 { font-size: 1.15em; }

.reveal p { margin: 0.4em 0; line-height: 1.35; }
.reveal strong { font-weight: 700; }

.reveal .kicker {
  font-size: 0.55em;
  font-weight: 600;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 0.6em;
}

.reveal .muted { color: var(--muted); }
.reveal .small { font-size: 0.7em; }
.reveal .center { text-align: center; }

/* article colours */
.reveal .indef { color: var(--indef); font-weight: 700; }
.reveal .def { color: var(--def); font-weight: 700; }
.reveal .zero { color: var(--zero); font-weight: 700; }
.reveal .right { color: var(--right); font-weight: 700; }
.reveal .wrong { color: var(--wrong); text-decoration: line-through; text-decoration-thickness: 3px; }

/* phonetic transcription */
.reveal .ipa {
  font-family: var(--font-ipa);
  color: var(--muted);
  font-size: 0.8em;
  white-space: nowrap;
}
.reveal .ipa b { color: var(--ink); font-weight: 700; }

/* fill-in blank: underline that the answer fades into */
.reveal .blank {
  display: inline-block;
  min-width: 2.4em;
  border-bottom: 4px solid var(--ink);
  text-align: center;
  line-height: 1.1;
  margin-right: 0.15em;
}

/* rows of examples */
.reveal .rows { display: grid; gap: 0.55em; margin: 0.6em 0; }
.reveal .row {
  display: grid;
  grid-template-columns: 9.5em 1fr;
  align-items: baseline;
  gap: 0.8em;
  font-size: 1.15em;
}
.reveal .row .ipa { font-size: 0.65em; }

/* two-column grid of cards */
.reveal .grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.7em;
  margin-top: 0.4em;
}
.reveal .grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.6em;
  margin-top: 0.4em;
}

.reveal .card {
  background: var(--card);
  border: 2px solid var(--line);
  border-radius: 14px;
  padding: 0.55em 0.75em;
}
.reveal .card h3 { margin-bottom: 0.3em; }
.reveal .card .label {
  font-size: 0.55em;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.reveal .card.def-card { border-color: var(--def); }
.reveal .card.zero-card { border-color: var(--zero); }

/* big rule / takeaway banner */
.reveal .rule {
  margin-top: 0.8em;
  padding: 0.45em 0.8em;
  border-left: 8px solid var(--indef);
  background: #eef3fc;
  border-radius: 0 12px 12px 0;
  font-size: 1em;
}
.reveal .rule.def-rule { border-color: var(--def); background: #fdf0e9; }
.reveal .rule.zero-rule { border-color: var(--zero); background: #f3eefe; }

/* title slide */
.reveal .title-slide h1 { margin-bottom: 0.3em; }
.reveal .title-slide .chips { display: flex; gap: 0.4em; margin: 0.4em 0 1em; }
.reveal .chip {
  font-family: var(--font-head);
  font-size: 1.2em;
  padding: 0.05em 0.55em;
  border-radius: 999px;
  border: 3px solid currentColor;
}

/* dialogue bubbles */
.reveal .bubble {
  display: inline-block;
  background: var(--card);
  border: 2px solid var(--line);
  border-radius: 18px;
  padding: 0.4em 0.8em;
  margin: 0.25em 0;
  font-size: 1.05em;
}
.reveal .bubble.reply { border-color: var(--def); margin-left: 3em; }

/* example pairs on the final "meaning" slide */
.reveal .pair { font-size: 0.75em; }
.reveal .pair p { margin: 0.25em 0; }
.reveal .pair .meaning { color: var(--muted); font-size: 0.85em; }

/* timeline on the origin slide */
.reveal .timeline { display: flex; align-items: center; gap: 0.6em; margin: 0.6em 0; font-size: 1.1em; }
.reveal .timeline .step { text-align: center; }
.reveal .timeline .step .word { font-family: var(--font-head); font-size: 1.6em; display: block; }
.reveal .timeline .step .when { font-size: 0.5em; color: var(--muted); text-transform: uppercase; letter-spacing: 0.08em; }
.reveal .timeline .arrow { color: var(--muted); font-size: 1.2em; }

/* reveal.js chrome */
.reveal .controls { color: var(--def); }
.reveal .progress { color: var(--def); height: 5px; }
.reveal .slide-number {
  background: transparent;
  color: var(--muted);
  font-family: var(--font-body);
  font-size: 16px;
}

/* highlight fragment variants in theme colours */
.reveal .fragment.highlight-def.visible { color: var(--def); }

/* larger transcriptions inside takeaway lines */
.reveal .rule .ipa,
.reveal .rows > p .ipa { font-size: 1em; color: var(--def); }

/* denser 3-row card grid */
.reveal .grid-2.tight { gap: 0.45em 0.7em; }
.reveal .grid-2.tight .card { padding: 0.3em 0.75em; }
.reveal .grid-2.tight .card p { margin: 0.1em 0; }

/* fragment that is visible from the start and gets crossed out on click */
.reveal .fragment.strike { opacity: 1; visibility: inherit; transition: color 0.3s ease; }
.reveal .fragment.strike.visible {
  color: var(--wrong);
  text-decoration: line-through;
  text-decoration-thickness: 3px;
}

/* 4-row variant of the tight card grid */
.reveal .grid-2.tight-4 { font-size: 0.9em; gap: 0.35em 0.7em; }
.reveal .grid-2.tight-4 .card { padding: 0.2em 0.75em; }

/* example line with transcription: word left, IPA right */
.reveal .card p.ex {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 0.5em;
  font-size: 0.9em;
}
.reveal .card p.ex .ipa { font-size: 0.75em; }