@font-face {
  font-family: "Sofia Sans Condensed";
  src: url("./fonts/SofiaSansCondensed-Italic.ttf") format("truetype");
  font-style: italic;
  font-weight: 400;
  font-display: swap;
}

@font-face {
  font-family: "Great Vibes";
  src: url("./fonts/GreatVibes-Regular.ttf") format("truetype");
  font-style: normal;
  font-weight: 400;
  font-display: swap;
}

:root {
  color-scheme: light;
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Noto Sans KR", "Segoe UI", sans-serif;
  color: #191f28;
  background: #fff;
  line-height: 1.5;
  --ink: #191f28;
  --muted: #4e5968;
  --quiet: #8b95a1;
  --line: #e5e8eb;
  --line-strong: #d1d6db;
  --soft: #f2f4f6;
  --focus: #007aff;
  --focus-soft: #edf4ff;
  --radius: 8px;
}

* { box-sizing: border-box; }
body { min-height: 100vh; margin: 0; padding: 0 18px 86px; background: #fff; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: default; opacity: .4; }
p, h1, h2, h3 { margin: 0; }

.app-header {
  position: sticky;
  z-index: 20;
  top: 0;
  width: 100%;
  max-width: 1680px;
  margin: 0 auto;
  padding: 13px 0 10px;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, #fff 93%, transparent);
  backdrop-filter: blur(18px);
}

.brand { display: flex; align-items: baseline; gap: 10px; }
.brand h1 { font-size: 18px; font-weight: 790; letter-spacing: -.045em; }
.level-picker, .font-picker { display: inline-flex; align-items: center; gap: 2px; }
.level-picker { padding: 2px; border: 1px solid var(--line); border-radius: var(--radius); }
.level-picker button { min-width: 32px; min-height: 26px; padding: 0 7px; border: 0; border-radius: 6px; color: var(--quiet); background: transparent; font-size: 10px; font-weight: 760; }
.level-picker button[aria-pressed="true"] { color: var(--ink); background: var(--soft); }
.course-progress { color: var(--muted); font-size: 11px; font-weight: 680; }

.study-shell {
  width: 100%;
  max-width: 1680px;
  margin: 0 auto;
  padding-top: 22px;
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(390px, .8fr);
  gap: clamp(24px, 3vw, 48px);
  align-items: start;
}
.lesson-column { min-width: 0; }
.lesson-heading { min-height: 70px; }
.eyebrow { color: var(--quiet); font-size: 10px; font-weight: 760; letter-spacing: .105em; text-transform: uppercase; }
.lesson-heading h2 { margin-top: 3px; font-size: 20px; font-weight: 760; line-height: 1.28; letter-spacing: -.035em; }
.page-purpose { max-width: 920px; margin-top: 5px; color: var(--muted); font-size: 12px; line-height: 1.55; }

.playback-bar {
  position: sticky;
  z-index: 12;
  top: 52px;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 8px 0 12px;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, #fff 94%, transparent);
  backdrop-filter: blur(12px);
}
.playback-bar button, .micro-actions button, .page-dock button {
  min-width: 104px;
  min-height: 38px;
  padding: 0 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  color: var(--ink);
  background: #fff;
  font-size: 12px;
  font-weight: 700;
  white-space: nowrap;
}
.playback-bar button:hover:not(:disabled), .micro-actions button:hover:not(:disabled), .page-dock button:hover:not(:disabled) { background: var(--soft); }
.primary { color: #fff !important; border-color: var(--ink) !important; background: var(--ink) !important; }
.primary:hover:not(:disabled) { background: #0f1419 !important; }
.playback-bar button.playing, .row-play.playing { color: #fff; border-color: var(--focus); background: var(--focus); }
.font-picker { margin-left: auto; }
.font-picker button { min-width: 74px; font-size: 11px; }
.font-picker button[aria-pressed="true"] { background: var(--soft); }
.status { min-width: 0; color: var(--quiet); font-size: 10px; }
.status:empty { display: none; }
.playback-bar .speech-result { flex-basis: 100%; margin-top: 2px; }

.dialogue { border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.turn { display: grid; grid-template-columns: 36px minmax(0, 1fr) 44px; gap: 12px; padding: 19px 10px 20px; border-bottom: 1px solid var(--line); }
.turn:last-child { border-bottom: 0; }
.turn.active { background: #f7f8fa; }
.speaker { padding-top: 4px; color: #6b7684; font-size: 10px; font-weight: 780; text-align: center; }
.russian-line { font-family: "Noto Sans", system-ui, sans-serif; font-size: 17px; font-weight: 520; line-height: 1.58; }
.korean-line { margin-top: 3px; color: var(--muted); font-size: 13px; line-height: 1.5; }
.word-button { display: inline; min-height: 0; margin: 0; padding: 0; border: 0; border-radius: 2px; color: inherit; background: transparent; font: inherit; line-height: inherit; text-align: inherit; }
.word-button:hover, .word-button:focus-visible { background: var(--focus-soft); outline: none; }
.stress { color: var(--focus); }
.row-play { width: 44px; height: 34px; padding: 0; border: 1px solid var(--line-strong); border-radius: var(--radius); color: var(--muted); background: #fff; font-size: 12px; font-weight: 760; }

.handwriting-one .russian-line, .handwriting-one .expression-russian, .handwriting-one .related-russian { font-family: "Sofia Sans Condensed", cursive; font-style: italic; font-weight: 400; letter-spacing: .015em; }
.handwriting-one .russian-line { font-size: 20px; line-height: 1.64; }
.handwriting-two .russian-line, .handwriting-two .expression-russian, .handwriting-two .related-russian { font-family: "Great Vibes", cursive; font-weight: 400; font-variant-ligatures: common-ligatures contextual; font-feature-settings: "liga" 1, "calt" 1; }
.handwriting-two .russian-line { font-size: 25px; line-height: 1.72; }

.inspector { position: sticky; top: 69px; max-height: calc(100vh - 88px); overflow: auto; padding-left: 22px; border-left: 1px solid var(--line); scrollbar-width: thin; }
.inspector-section { padding: 16px 0 18px; border-bottom: 1px solid var(--line); }
.grammar-change { margin-top: 9px; font-size: 15px; font-weight: 720; }
.grammar-note, .grammar-pronunciation { margin-top: 6px; color: var(--ink); font-size: 12px; line-height: 1.62; }
.grammar-pronunciation { color: var(--muted); }
.grammar-term { margin-top: 8px; color: var(--quiet); font-size: 11px; }
.grammar-term:empty { display: none; }
.empty { margin-top: 8px; color: var(--quiet); font-size: 12px; line-height: 1.6; }
.expression-head { margin-top: 8px; }
.expression-russian { font-family: "Noto Sans", system-ui, sans-serif; font-size: 19px; font-weight: 700; }
.expression-lemma { margin-top: 3px; color: var(--quiet); font-size: 11px; }
.expression-meaning { margin-top: 8px; font-size: 14px; font-weight: 650; }
.expression-clue { margin-top: 4px; color: var(--muted); font-size: 12px; }
.pronunciation { margin-top: 12px; padding-top: 11px; border-top: 1px solid var(--line); }
.pronunciation p { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 12px; }
.related { margin-top: 14px; }
.related h3 { color: var(--quiet); font-size: 10px; letter-spacing: .08em; }
.related-item { margin-top: 8px; }
.related-russian { font-family: "Noto Sans", system-ui, sans-serif; font-size: 14px; font-weight: 650; }
.related-korean { margin-top: 1px; color: var(--muted); font-size: 11px; }
.external-links { display: flex; gap: 12px; margin-top: 14px; }
.external-links a { color: var(--muted); font-size: 11px; font-weight: 700; text-decoration: none; }
.external-links a:hover { color: var(--ink); text-decoration: underline; }

.micro-prompt { margin-top: 20px; padding: 16px 0; border-top: 1px solid var(--line-strong); }
.micro-prompt h3 { margin-top: 4px; font-size: 17px; }
.micro-actions { display: flex; gap: 7px; margin-top: 12px; }
.speech-result { margin-top: 10px; color: var(--muted); font-size: 13px; }
.speech-result:empty { display: none; }

.page-dock { position: fixed; z-index: 30; right: 18px; bottom: 18px; display: grid; grid-template-columns: repeat(2, 112px); gap: 7px; padding: 7px; border: 1px solid var(--line); border-radius: 11px; background: color-mix(in srgb, #fff 94%, transparent); box-shadow: 0 7px 25px rgb(0 0 0 / 8%); backdrop-filter: blur(14px); }
.page-dock button { width: 112px; min-width: 112px; }

@media (max-width: 900px) {
  body { padding-inline: 14px; }
  .study-shell { grid-template-columns: 1fr; gap: 16px; }
  .inspector { position: static; max-height: none; padding-left: 0; border-left: 0; border-top: 1px solid var(--line); }
  .font-picker { margin-left: 0; }
  .page-dock { right: 12px; bottom: 12px; }
}

@media (max-width: 560px) {
  .app-header { align-items: center; }
  .playback-bar button { min-width: 88px; }
  .font-picker { width: 100%; }
  .font-picker button { flex: 1; min-width: 0; }
  .turn { grid-template-columns: 26px minmax(0, 1fr) 40px; gap: 8px; padding-inline: 2px; }
  .row-play { width: 40px; }
  .page-dock { left: 12px; grid-template-columns: repeat(2, 1fr); }
  .page-dock button { width: auto; min-width: 0; }
}