/* DAT Prep — porcelain & teal clinical palette */
:root {
  --porcelain: #F7FAFB;
  --enamel: #FFFFFF;
  --ink: #12303B;
  --ink-soft: #4A6570;
  --teal: #0E5E63;
  --teal-bright: #1B7F8C;
  --mint: #DCEFEC;
  --amber: #C77E2E;
  --amber-soft: #F6E8D4;
  --coral: #B03A5B;
  --line: #D8E4E6;
  --radius: 14px;
  --font-display: "Archivo", "Apple SD Gothic Neo", sans-serif;
  --font-body: "Apple SD Gothic Neo", "Pretendard", -apple-system, "Malgun Gothic", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
body {
  font-family: var(--font-body);
  background: var(--porcelain);
  color: var(--ink);
  line-height: 1.65;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ---------- top bar ---------- */
.topbar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 14px 28px;
  background: var(--enamel);
  border-bottom: 1px solid var(--line);
  position: sticky; top: 0; z-index: 20;
}
.brand { text-decoration: none; display: flex; align-items: baseline; gap: 10px; }
.brand-mark {
  font-family: var(--font-display);
  font-weight: 900; font-stretch: 115%;
  font-size: 1.5rem; letter-spacing: 0.04em;
  color: var(--teal);
}
.brand-sub {
  font-family: var(--font-mono); font-size: 0.72rem;
  color: var(--ink-soft); letter-spacing: 0.12em; text-transform: uppercase;
}
.topnav { display: flex; gap: 6px; }
.topnav a {
  text-decoration: none; color: var(--ink-soft);
  font-size: 0.92rem; font-weight: 600;
  padding: 7px 14px; border-radius: 999px;
  transition: background 0.15s, color 0.15s;
}
.topnav a:hover { background: var(--mint); color: var(--teal); }
.topnav a.active { background: var(--teal); color: #fff; }

.app { flex: 1; width: 100%; max-width: 1020px; margin: 0 auto; padding: 32px 24px 72px; }
.footer { text-align: center; padding: 22px; color: var(--ink-soft); font-size: 0.82rem; border-top: 1px solid var(--line); background: var(--enamel); }

/* ---------- dashboard hero: dental arch ---------- */
.hero { text-align: center; margin-bottom: 8px; }
.hero h1 {
  font-family: var(--font-display); font-weight: 800; font-stretch: 110%;
  font-size: clamp(1.6rem, 4vw, 2.4rem); color: var(--ink);
  letter-spacing: -0.01em;
}
.hero h1 em { font-style: normal; color: var(--teal); }
.hero p.lede { color: var(--ink-soft); max-width: 560px; margin: 10px auto 0; font-size: 0.98rem; }

.arch-wrap { margin: 8px auto 4px; max-width: 720px; position: relative; }
.arch-wrap svg { width: 100%; height: auto; display: block; }
.tooth { cursor: pointer; }
.tooth-shape {
  fill: var(--enamel); stroke-width: 2;
  transition: fill 0.25s, transform 0.2s;
}
.tooth:hover .tooth-shape { filter: brightness(0.96); }
.tooth.done .tooth-shape { }
.tooth-num {
  font-family: var(--font-mono); font-size: 11px; font-weight: 600;
  fill: var(--ink-soft); text-anchor: middle; pointer-events: none;
}
.tooth.done .tooth-num { fill: #fff; }
.arch-caption {
  text-align: center; font-family: var(--font-mono); font-size: 0.75rem;
  color: var(--ink-soft); letter-spacing: 0.08em;
}
.arch-caption b { color: var(--teal); font-weight: 600; }

/* ---------- legend ---------- */
.legend { display: flex; flex-wrap: wrap; justify-content: center; gap: 10px 18px; margin: 14px 0 34px; }
.legend span { display: inline-flex; align-items: center; gap: 6px; font-size: 0.8rem; color: var(--ink-soft); }
.legend i { width: 11px; height: 11px; border-radius: 3px; display: inline-block; }

/* ---------- phase / session list ---------- */
.phase { margin-bottom: 30px; }
.phase-head { display: flex; align-items: baseline; gap: 12px; margin-bottom: 12px; }
.phase-head .phase-no {
  font-family: var(--font-mono); color: var(--amber); font-size: 0.8rem; letter-spacing: 0.1em;
}
.phase-head h2 { font-family: var(--font-display); font-weight: 800; font-size: 1.2rem; }
.phase-head p { color: var(--ink-soft); font-size: 0.85rem; }

.session-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(290px, 1fr)); gap: 12px; }
.session-card {
  background: var(--enamel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px 18px; text-decoration: none; color: var(--ink);
  display: flex; flex-direction: column; gap: 6px;
  transition: border-color 0.15s, box-shadow 0.15s, transform 0.15s;
  border-left: 5px solid var(--line);
}
.session-card:hover { border-color: var(--teal-bright); box-shadow: 0 4px 16px rgba(14,94,99,0.08); transform: translateY(-1px); }
.session-card .sc-top { display: flex; justify-content: space-between; align-items: center; }
.session-card .sc-no { font-family: var(--font-mono); font-size: 0.72rem; color: var(--ink-soft); letter-spacing: 0.08em; }
.session-card .sc-badge {
  font-size: 0.68rem; font-weight: 700; padding: 2px 9px; border-radius: 999px;
  background: var(--mint); color: var(--teal);
}
.session-card.done .sc-badge { background: var(--teal); color: #fff; }
.session-card h3 { font-size: 1rem; font-weight: 700; line-height: 1.4; }
.session-card .sc-sub { font-size: 0.82rem; color: var(--ink-soft); }
.session-card .sc-meta { font-family: var(--font-mono); font-size: 0.7rem; color: var(--ink-soft); margin-top: 4px; }

/* ---------- session page ---------- */
.crumb { font-family: var(--font-mono); font-size: 0.75rem; color: var(--ink-soft); margin-bottom: 14px; }
.crumb a { color: var(--teal); text-decoration: none; }
.session-head { border-left: 6px solid var(--teal); padding-left: 18px; margin-bottom: 26px; }
.session-head .subject-tag { font-family: var(--font-mono); font-size: 0.75rem; letter-spacing: 0.1em; text-transform: uppercase; }
.session-head h1 { font-family: var(--font-display); font-weight: 800; font-size: 1.7rem; margin: 4px 0; }
.session-head p { color: var(--ink-soft); max-width: 640px; }

.step-tabs { display: flex; gap: 8px; margin: 22px 0; flex-wrap: wrap; }
.step-tabs button {
  font-family: var(--font-body); font-size: 0.88rem; font-weight: 700;
  border: 1px solid var(--line); background: var(--enamel); color: var(--ink-soft);
  border-radius: 999px; padding: 9px 20px; cursor: pointer;
  transition: all 0.15s;
}
.step-tabs button.active { background: var(--teal); border-color: var(--teal); color: #fff; }
.step-tabs button:hover:not(.active) { border-color: var(--teal-bright); color: var(--teal); }

.concept {
  background: var(--enamel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px 24px; margin-bottom: 14px;
}
.concept h3 { font-size: 1.05rem; margin-bottom: 2px; }
.concept h3 .term-en { font-family: var(--font-display); font-weight: 700; color: var(--teal); }
.concept .concept-ko { font-size: 0.85rem; color: var(--amber); font-weight: 700; margin-bottom: 8px; }
.concept p.desc { font-size: 0.94rem; margin-bottom: 10px; }
.concept ul { padding-left: 20px; font-size: 0.9rem; color: var(--ink); }
.concept ul li { margin-bottom: 4px; }
.concept .example {
  margin-top: 10px; background: var(--amber-soft); border-radius: 8px;
  padding: 10px 14px; font-size: 0.86rem;
}
.concept .example::before { content: "예시 · "; font-weight: 800; color: var(--amber); }

/* ---------- flashcards ---------- */
.flash-stage { max-width: 560px; margin: 0 auto; text-align: center; }
.flash-card {
  background: var(--enamel); border: 1px solid var(--line); border-radius: 18px;
  min-height: 260px; display: flex; flex-direction: column; justify-content: center; align-items: center;
  padding: 28px; cursor: pointer; box-shadow: 0 6px 24px rgba(18,48,59,0.06);
  transition: transform 0.15s;
}
.flash-card:hover { transform: translateY(-2px); }
.flash-card .fc-side { font-family: var(--font-mono); font-size: 0.7rem; letter-spacing: 0.15em; color: var(--amber); margin-bottom: 14px; text-transform: uppercase; }
.flash-card .fc-term { font-family: var(--font-display); font-weight: 800; font-size: 1.5rem; color: var(--teal); }
.flash-card .fc-back { font-size: 0.95rem; text-align: left; }
.flash-card .fc-back ul { padding-left: 18px; margin-top: 8px; }
.flash-nav { display: flex; justify-content: center; gap: 10px; margin-top: 18px; align-items: center; }
.flash-nav .fc-count { font-family: var(--font-mono); font-size: 0.8rem; color: var(--ink-soft); min-width: 70px; }

/* ---------- quiz ---------- */
.quiz-item { background: var(--enamel); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px 24px; margin-bottom: 14px; }
.quiz-item .q-no { font-family: var(--font-mono); font-size: 0.72rem; color: var(--amber); letter-spacing: 0.1em; margin-bottom: 6px; }
.quiz-item .q-text { font-weight: 700; margin-bottom: 12px; white-space: pre-wrap; }
.choices { display: flex; flex-direction: column; gap: 8px; }
.choices button {
  text-align: left; font-family: var(--font-body); font-size: 0.92rem;
  background: var(--porcelain); border: 1px solid var(--line); border-radius: 10px;
  padding: 10px 14px; cursor: pointer; color: var(--ink);
  transition: all 0.12s; white-space: pre-wrap;
}
.choices button:hover:not(:disabled) { border-color: var(--teal-bright); background: var(--mint); }
.choices button:disabled { cursor: default; }
.choices button.correct { background: var(--mint); border-color: var(--teal); color: var(--teal); font-weight: 700; }
.choices button.wrong { background: #FBEAEF; border-color: var(--coral); color: var(--coral); }
.explain {
  margin-top: 12px; border-left: 4px solid var(--teal); background: var(--porcelain);
  padding: 10px 14px; font-size: 0.88rem; border-radius: 0 8px 8px 0; display: none;
}
.explain.show { display: block; }
.explain b { color: var(--teal); }

.quiz-result {
  text-align: center; background: var(--enamel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 28px; margin-top: 20px;
}
.quiz-result .score { font-family: var(--font-display); font-weight: 900; font-size: 2.4rem; color: var(--teal); }
.quiz-result p { color: var(--ink-soft); font-size: 0.9rem; }

/* ---------- buttons ---------- */
.btn {
  display: inline-block; font-family: var(--font-body); font-weight: 700; font-size: 0.92rem;
  background: var(--teal); color: #fff; border: none; border-radius: 999px;
  padding: 11px 26px; cursor: pointer; text-decoration: none;
  transition: background 0.15s, transform 0.1s;
}
.btn:hover { background: var(--teal-bright); }
.btn:active { transform: scale(0.98); }
.btn.ghost { background: transparent; color: var(--teal); border: 1.5px solid var(--teal); }
.btn.ghost:hover { background: var(--mint); }
.btn.amber { background: var(--amber); }
.btn:disabled { opacity: 0.45; cursor: default; }
.btn:focus-visible, .choices button:focus-visible, .step-tabs button:focus-visible, a:focus-visible {
  outline: 3px solid var(--amber); outline-offset: 2px;
}

/* ---------- exam / about ---------- */
.panel { background: var(--enamel); border: 1px solid var(--line); border-radius: var(--radius); padding: 24px 28px; margin-bottom: 16px; }
.panel h2 { font-family: var(--font-display); font-weight: 800; font-size: 1.25rem; margin-bottom: 10px; }
.panel h3 { font-size: 1rem; margin: 14px 0 6px; color: var(--teal); }
.panel p, .panel li { font-size: 0.93rem; }
.panel ul, .panel ol { padding-left: 22px; }
.panel table { width: 100%; border-collapse: collapse; font-size: 0.88rem; margin: 10px 0; }
.panel th, .panel td { border: 1px solid var(--line); padding: 8px 12px; text-align: left; }
.panel th { background: var(--mint); color: var(--teal); font-family: var(--font-mono); font-size: 0.78rem; }
.exam-config { display: flex; flex-wrap: wrap; gap: 10px; margin: 14px 0; }
.exam-config label {
  display: inline-flex; align-items: center; gap: 6px; font-size: 0.88rem;
  background: var(--porcelain); border: 1px solid var(--line); border-radius: 999px; padding: 7px 14px; cursor: pointer;
}
.exam-config input { accent-color: var(--teal); }
.exam-meta { font-family: var(--font-mono); font-size: 0.78rem; color: var(--ink-soft); margin-bottom: 14px; }

.progress-bar { height: 8px; background: var(--line); border-radius: 999px; overflow: hidden; margin: 6px 0 2px; }
.progress-bar i { display: block; height: 100%; background: var(--teal); border-radius: 999px; transition: width 0.4s; }

.session-foot { display: flex; justify-content: space-between; align-items: center; margin-top: 28px; flex-wrap: wrap; gap: 12px; }

/* ---------- PAT lab ---------- */
.pat-panels { display: flex; flex-wrap: wrap; gap: 14px; margin: 12px 0 16px; align-items: flex-end; }
.pat-panel { background: var(--porcelain); border: 1px solid var(--line); border-radius: 10px; padding: 8px; display: inline-flex; flex-direction: column; align-items: center; gap: 4px; }
.pat-panel svg { display: block; max-width: 190px; }
.pat-step { font-family: var(--font-mono); font-size: 0.68rem; color: var(--amber); }
.pat-stats { margin: 0 0 16px; font-size: 0.9rem; color: var(--ink-soft); display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.pat-stats b { color: var(--teal); }
.opt-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; }
.opt-panel {
  background: var(--porcelain); border: 1.5px solid var(--line); border-radius: 10px;
  padding: 10px; cursor: pointer; display: flex; flex-direction: column; align-items: center; gap: 6px;
  transition: all 0.12s; font-family: var(--font-body);
}
.opt-panel svg { max-width: 130px; display: block; }
.opt-panel:hover:not(:disabled) { border-color: var(--teal-bright); background: var(--mint); }
.opt-panel .opt-label { font-family: var(--font-mono); font-size: 0.75rem; font-weight: 600; color: var(--ink-soft); }
.opt-panel .opt-text { font-size: 1rem; font-weight: 700; }
.opt-panel.correct { border-color: var(--teal); background: var(--mint); }
.opt-panel.wrong { border-color: var(--coral); background: #FBEAEF; }
.opt-panel.selected { border-color: var(--teal); background: var(--mint); box-shadow: 0 0 0 2px var(--teal) inset; }
.choices button.selected { border-color: var(--teal); background: var(--mint); font-weight: 700; box-shadow: 0 0 0 1.5px var(--teal) inset; }
.opt-panel:disabled { cursor: default; }

/* ---------- CBT exam ---------- */
.exam-head {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  background: var(--ink); color: #fff; border-radius: var(--radius);
  padding: 12px 20px; margin-bottom: 16px; position: sticky; top: 64px; z-index: 10;
}
.exam-sec { font-family: var(--font-display); font-weight: 800; font-size: 0.95rem; }
.exam-timer { font-family: var(--font-mono); font-weight: 600; font-size: 1.05rem; color: #9FE8DB; }
.exam-timer.low { color: #FF9DB5; }
.exam-prog { font-family: var(--font-mono); font-size: 0.78rem; color: #B8CDD3; }
.exam-foot { display: flex; gap: 8px; flex-wrap: wrap; margin: 14px 0; }
.palette { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 10px; }
.palette .pal {
  width: 34px; height: 30px; font-family: var(--font-mono); font-size: 0.72rem;
  border: 1px solid var(--line); background: var(--enamel); border-radius: 6px; cursor: pointer; color: var(--ink-soft);
}
.palette .pal.ans { background: var(--mint); border-color: var(--teal-bright); color: var(--teal); font-weight: 700; }
.palette .pal.cur { outline: 2px solid var(--amber); }
.palette .pal.flag { box-shadow: inset 0 -3px 0 var(--coral); }
.rc-passage {
  background: var(--enamel); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px 22px; margin-bottom: 14px; max-height: 320px; overflow-y: auto; font-size: 0.92rem;
}
.rc-passage h3 { color: var(--teal); margin-bottom: 8px; }
.rc-passage p { margin-bottom: 10px; }

@media (max-width: 640px) {
  .topbar { padding: 12px 16px; }
  .brand-sub { display: none; }
  .app { padding: 22px 14px 56px; }
  .session-grid { grid-template-columns: 1fr; }
}
.footer-legal { margin-top: 8px; font-size: 0.72rem; opacity: 0.75; }
.footer-legal a { color: inherit; }