/* ═══════════════════════════════════════════════════════
   base.css — 리셋, 폰트, 공통 레이아웃
   테마별 색상/효과는 theme-bento.css / theme-dark.css
   ═══════════════════════════════════════════════════════ */

@import url("https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/static/pretendard.min.css");

/* ── 리셋 ── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: "Pretendard", "Noto Sans KR", -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  letter-spacing: -0.015em;
  min-height: 100vh;
  background: var(--c-bg);
  color: var(--c-text);
  transition: background 0.25s ease, color 0.25s ease;
}

a { color: inherit; text-decoration: none; }
button { font-family: inherit; cursor: pointer; border: none; background: none; color: inherit; }
input, textarea { font-family: inherit; font-size: inherit; }
img { max-width: 100%; display: block; }
ul, ol { list-style: none; }

/* ── 레이아웃 컨테이너 ── */
.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 24px 20px;
}

.page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ── 상단 바 ── */
.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 18px 24px;
  border-bottom: var(--c-border);
  background: var(--c-surface);
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(10px);
}

.app-header .brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
}
.app-header .brand-title {
  font-size: 18px;
  font-weight: 800;
  color: var(--c-heading);
  letter-spacing: -0.3px;
}
.app-header .brand-sub {
  font-size: 13px;
  color: var(--c-text);
  opacity: 0.7;
}

.header-actions { display: flex; gap: 8px; align-items: center; }

/* ── 버튼 ── */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 18px;
  border-radius: var(--c-radius-sm);
  font-weight: 600;
  font-size: 15px;
  letter-spacing: -0.2px;
  transition: all 0.15s ease;
  white-space: nowrap;
}
.btn-primary { background: var(--c-accent); color: #fff; }
.btn-primary:hover { filter: brightness(1.05); transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { background: var(--c-text); opacity: 0.3; cursor: not-allowed; transform: none; }

.btn-secondary {
  background: var(--c-surface-2);
  color: var(--c-heading);
  border: var(--c-border);
}
.btn-secondary:hover { background: var(--c-surface-3); }

.btn-ghost { color: var(--c-text); padding: 8px 12px; }
.btn-ghost:hover { background: var(--c-surface-2); color: var(--c-heading); }

.btn-icon {
  width: 38px; height: 38px;
  padding: 0;
  border-radius: 10px;
  background: var(--c-surface-2);
  color: var(--c-heading);
  font-size: 18px;
}
.btn-icon:hover { background: var(--c-surface-3); }

.btn-sm { padding: 6px 12px; font-size: 13px; }
.btn-lg { padding: 14px 24px; font-size: 17px; font-weight: 700; }

/* ── 카드 ── */
.card {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 20px;
  border: var(--c-border);
  box-shadow: var(--c-shadow);
}
.card-accent { border-top: 3px solid var(--c-accent); }

/* ── 태그 ── */
.tag {
  display: inline-block;
  font-size: 12px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 999px;
  background: var(--c-accent-soft);
  color: var(--c-accent-strong);
  letter-spacing: 0;
}
.tag-topic { background: var(--c-surface-2); color: var(--c-text); margin-left: 6px; }
.tag-difficulty-easy { background: rgba(100, 180, 120, 0.15); color: #3a8a4f; }
.tag-difficulty-medium { background: rgba(200, 150, 60, 0.15); color: #a06000; }
.tag-difficulty-hard { background: rgba(200, 80, 80, 0.15); color: #c83c3c; }

/* ── 타이포 유틸 ── */
.h1 { font-size: 32px; font-weight: 900; color: var(--c-heading); letter-spacing: -0.8px; line-height: 1.25; }
.h2 { font-size: 24px; font-weight: 800; color: var(--c-heading); letter-spacing: -0.4px; }
.h3 { font-size: 19px; font-weight: 700; color: var(--c-heading); }
.muted { color: var(--c-text); opacity: 0.75; }
.small { font-size: 13px; }
.mono { font-family: "JetBrains Mono", "SF Mono", ui-monospace, monospace; }

/* ── 홈 화면 ── */
.hero { text-align: center; padding: 56px 20px 40px; }
.hero .hero-title {
  font-size: 38px;
  font-weight: 900;
  color: var(--c-heading);
  letter-spacing: -1px;
  margin-bottom: 12px;
  line-height: 1.2;
}
.hero .hero-sub { font-size: 17px; color: var(--c-text); opacity: 0.8; }
.hero .hero-badge {
  display: inline-block;
  margin-bottom: 16px;
  padding: 6px 14px;
  border-radius: 999px;
  background: var(--c-accent-soft);
  color: var(--c-accent-strong);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.5px;
}

.set-grid {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 16px;
  margin: 40px auto;
  width: 100%;
}
.set-grid > .set-card {
  flex: 0 0 200px;
  max-width: 240px;
}

.set-card {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 24px 20px;
  border: var(--c-border);
  box-shadow: var(--c-shadow);
  cursor: pointer;
  transition: all 0.18s ease;
  position: relative;
  overflow: hidden;
  min-height: 200px;
  display: flex;
  flex-direction: column;
}
.set-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 100%; height: 4px;
  background: var(--c-accent);
  opacity: 0.5;
  transition: opacity 0.2s;
}
.set-card:hover { transform: translateY(-3px); box-shadow: var(--c-shadow-hover); border-color: var(--c-accent); }
.set-card:hover::before { opacity: 1; }

.set-card .set-num { font-size: 12px; font-weight: 700; color: var(--c-accent-strong); letter-spacing: 1.5px; }
.set-card .set-title {
  font-size: 24px;
  font-weight: 800;
  color: var(--c-heading);
  margin: 6px 0 12px;
  letter-spacing: -0.5px;
}
.set-card .set-meta {
  font-size: 14px;
  color: var(--c-text);
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 16px;
  margin-top: auto;
  border-top: 1px dashed var(--c-border-soft);
}
.set-card .set-best { font-weight: 700; color: var(--c-heading); }
.set-card .set-best.unplayed { color: var(--c-text); opacity: 0.45; }

/* ── 모드 선택 ── */
.mode-selector {
  display: flex;
  gap: 10px;
  padding: 6px;
  background: var(--c-surface-2);
  border-radius: 14px;
  max-width: 420px;
  margin: 0 auto;
}
.mode-btn {
  flex: 1;
  padding: 12px 16px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 14px;
  color: var(--c-text);
  transition: all 0.15s;
}
.mode-btn.active {
  background: var(--c-surface);
  color: var(--c-heading);
  box-shadow: var(--c-shadow);
}
.mode-btn:hover:not(.active) { color: var(--c-heading); }

/* ── 시험 화면 ── */
.exam-bar {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 14px 24px;
  background: var(--c-surface);
  border-bottom: var(--c-border);
  position: sticky;
  top: 0;
  z-index: 50;
}
.exam-bar .set-info { font-weight: 700; color: var(--c-heading); }
.exam-bar .qno { color: var(--c-text); font-size: 14px; }
.exam-bar .timer {
  font-family: "JetBrains Mono", ui-monospace, monospace;
  font-weight: 700;
  color: var(--c-heading);
  font-size: 15px;
  padding: 6px 12px;
  border-radius: 8px;
  background: var(--c-surface-2);
}
.exam-bar .spacer { flex: 1; }

.progress-bar {
  width: 100%;
  height: 6px;
  background: var(--c-surface-2);
  overflow: hidden;
}
.progress-bar .progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--c-accent), var(--c-accent-strong));
  transition: width 0.3s ease;
}

/* ── 문제 영역 ── */
.question-area { max-width: 820px; margin: 32px auto; padding: 0 20px; }
.q-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  flex-wrap: wrap;
  gap: 8px;
}
.q-tags { display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }

.bookmark-btn {
  width: 36px; height: 36px;
  border-radius: 10px;
  background: var(--c-surface-2);
  color: var(--c-text);
  font-size: 17px;
  transition: all 0.15s;
}
.bookmark-btn:hover, .bookmark-btn.active {
  background: var(--c-accent-soft);
  color: var(--c-accent-strong);
}

.question-body {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 28px;
  border: var(--c-border);
  box-shadow: var(--c-shadow);
  margin-bottom: 16px;
}
.question-body .q-num {
  font-size: 13px;
  color: var(--c-accent-strong);
  font-weight: 700;
  letter-spacing: 1px;
  margin-bottom: 6px;
}
.question-body .q-text {
  font-size: 18px;
  font-weight: 600;
  color: var(--c-heading);
  line-height: 1.6;
  margin-bottom: 20px;
  white-space: pre-wrap;
}
.question-body .q-image {
  max-width: 100%;
  border-radius: 12px;
  margin: 16px 0;
  border: var(--c-border);
}

/* ── 선택지 ── */
.choices { display: flex; flex-direction: column; gap: 10px; }
.choice {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 18px;
  border-radius: 14px;
  background: var(--c-surface-2);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all 0.15s;
  font-size: 16px;
  line-height: 1.55;
  color: var(--c-heading);
  text-align: left;
  width: 100%;
}
.choice:hover:not(:disabled):not(.locked) {
  background: var(--c-accent-soft);
  border-color: var(--c-accent);
}
.choice.selected {
  background: var(--c-accent-soft);
  border-color: var(--c-accent);
  font-weight: 600;
}
.choice.correct {
  background: rgba(80, 170, 110, 0.15);
  border-color: #4caf50;
}
.choice.incorrect {
  background: rgba(220, 80, 80, 0.12);
  border-color: #d9534f;
}
.choice.locked { cursor: default; }
.choice-index {
  flex-shrink: 0;
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--c-surface-3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 14px;
  color: var(--c-heading);
}
.choice.selected .choice-index,
.choice.correct .choice-index { background: var(--c-accent); color: #fff; }
.choice.incorrect .choice-index { background: #d9534f; color: #fff; }
.choice-text { flex: 1; padding-top: 2px; }

/* ── 주관식 입력 ── */
.short-input {
  width: 100%;
  padding: 14px 18px;
  border-radius: 14px;
  background: var(--c-surface-2);
  border: 2px solid transparent;
  color: var(--c-heading);
  font-size: 17px;
  font-weight: 600;
  transition: border-color 0.15s;
}
.short-input:focus {
  outline: none;
  border-color: var(--c-accent);
  background: var(--c-surface);
}
.short-input::placeholder { color: var(--c-text); opacity: 0.5; font-weight: 400; }

/* ── 해설 패널 ── */
.explain {
  margin-top: 14px;
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 20px 24px;
  border: var(--c-border);
  border-left: 4px solid var(--c-accent);
  animation: slideDown 0.3s ease;
}
@keyframes slideDown {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}
.explain-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--c-accent-strong);
  letter-spacing: 1px;
  margin-bottom: 8px;
}
.explain-brief { color: var(--c-heading); font-size: 15px; line-height: 1.7; }
.explain-brief p { margin: 0; }
.explain-brief p + p { margin-top: 8px; }
.explain-detailed {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px dashed var(--c-border-soft);
  color: var(--c-text);
  font-size: 14px;
  line-height: 1.8;
}
.explain-detailed p { margin: 0; }
.explain-detailed p + p { margin-top: 10px; }
.explain-brief strong, .explain-detailed strong { color: var(--c-heading); font-weight: 700; }
.explain-source {
  display: inline-block;
  margin-top: 10px;
  font-size: 12px;
  color: var(--c-accent-strong);
  font-weight: 600;
}
details.explain-toggle { margin-top: 10px; }
details.explain-toggle summary {
  cursor: pointer;
  font-size: 13px;
  color: var(--c-accent-strong);
  font-weight: 600;
  padding: 4px 0;
  list-style: none;
}
details.explain-toggle summary::-webkit-details-marker { display: none; }
details.explain-toggle summary::before { content: "▸ "; transition: transform 0.2s; display: inline-block; }
details.explain-toggle[open] summary::before { transform: rotate(90deg); }

/* ── 하단 네비 ── */
.exam-nav {
  position: sticky;
  bottom: 0;
  display: flex;
  gap: 10px;
  padding: 16px 24px;
  background: var(--c-surface);
  border-top: var(--c-border);
  justify-content: space-between;
  z-index: 40;
}
.exam-nav .nav-center { display: flex; gap: 10px; flex: 1; justify-content: center; }

/* ── 결과 화면 ── */
.result-hero { text-align: center; padding: 48px 20px 32px; }
.result-hero .result-emoji { font-size: 48px; margin-bottom: 12px; }
.result-hero .score-big {
  font-size: 64px;
  font-weight: 900;
  color: var(--c-accent-strong);
  letter-spacing: -2px;
  line-height: 1;
}
.result-hero .score-max { font-size: 24px; color: var(--c-text); font-weight: 600; }
.result-hero .percent { font-size: 20px; margin-top: 8px; color: var(--c-heading); font-weight: 700; }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 14px;
  margin: 24px 0;
}
.stat-card {
  background: var(--c-surface);
  border-radius: var(--c-radius-sm);
  padding: 18px 20px;
  border: var(--c-border);
  text-align: center;
}
.stat-card .stat-label { font-size: 12px; color: var(--c-text); letter-spacing: 1px; font-weight: 700; }
.stat-card .stat-value {
  font-size: 26px;
  font-weight: 800;
  color: var(--c-heading);
  margin-top: 6px;
  letter-spacing: -0.5px;
}

.week-chart {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 24px;
  border: var(--c-border);
}
.week-row {
  display: grid;
  grid-template-columns: 80px 1fr 60px;
  gap: 14px;
  align-items: center;
  margin-bottom: 10px;
}
.week-row:last-child { margin-bottom: 0; }
.week-label { font-weight: 700; color: var(--c-heading); font-size: 14px; }
.week-bar-bg { height: 18px; background: var(--c-surface-2); border-radius: 999px; overflow: hidden; }
.week-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--c-accent), var(--c-accent-strong));
  border-radius: 999px;
  transition: width 0.5s ease;
}
.week-score { font-weight: 700; text-align: right; color: var(--c-heading); font-size: 14px; }

.nickname-box {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  padding: 24px;
  border: var(--c-border);
  border-top: 4px solid var(--c-accent);
  display: flex;
  gap: 12px;
  align-items: center;
  flex-wrap: wrap;
}
.nickname-box label { font-weight: 700; color: var(--c-heading); white-space: nowrap; }
.nickname-box input {
  flex: 1;
  min-width: 160px;
  padding: 12px 16px;
  border-radius: 10px;
  border: 2px solid var(--c-border-soft);
  background: var(--c-surface-2);
  color: var(--c-heading);
  font-size: 15px;
  font-weight: 600;
}
.nickname-box input:focus { outline: none; border-color: var(--c-accent); }

.rank-table {
  background: var(--c-surface);
  border-radius: var(--c-radius);
  overflow: hidden;
  border: var(--c-border);
  width: 100%;
  border-collapse: collapse;
}
.rank-table th {
  background: var(--c-surface-2);
  color: var(--c-heading);
  font-size: 13px;
  font-weight: 700;
  padding: 12px 14px;
  text-align: left;
  letter-spacing: 0.3px;
}
.rank-table td {
  padding: 12px 14px;
  font-size: 14px;
  color: var(--c-heading);
  border-top: 1px solid var(--c-border-soft);
}
.rank-table tr.me td { background: var(--c-accent-soft); font-weight: 700; }
.rank-rank { font-weight: 900; color: var(--c-accent-strong); width: 44px; }
.rank-rank.medal-1 { color: #d4a017; }
.rank-rank.medal-2 { color: #9aa0a6; }
.rank-rank.medal-3 { color: #b08458; }

/* ── 스피너/토스트 ── */
.spinner {
  width: 20px; height: 20px;
  border: 2px solid var(--c-surface-2);
  border-top-color: var(--c-accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  display: inline-block;
}
@keyframes spin { to { transform: rotate(360deg); } }

.toast {
  position: fixed;
  bottom: 24px; left: 50%;
  transform: translateX(-50%);
  padding: 12px 20px;
  background: var(--c-heading);
  color: var(--c-surface);
  border-radius: 999px;
  font-size: 14px;
  font-weight: 600;
  box-shadow: 0 8px 24px rgba(0,0,0,0.2);
  z-index: 200;
  opacity: 0;
  transition: opacity 0.2s, transform 0.2s;
  pointer-events: none;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(-4px); }

/* ── 반응형 ── */
/* set-grid는 flex wrap + justify-content:center로 자동 대응 */
@media (max-width: 900px) {
  .set-grid { gap: 14px; margin: 32px auto; }
  .set-card { padding: 22px 18px; min-height: 180px; }
  .set-card .set-title { font-size: 22px; }
}
@media (max-width: 640px) {
  .container { padding: 16px 14px; }
  .hero { padding: 32px 16px 24px; }
  .hero .hero-title { font-size: 28px; }
  .h1 { font-size: 24px; }
  .question-body { padding: 20px 18px; }
  .question-body .q-text { font-size: 16px; }
  .exam-bar { padding: 12px 14px; gap: 8px; }
  .result-hero .score-big { font-size: 48px; }
  .set-grid { gap: 12px; margin: 24px auto; }
  .set-grid > .set-card { flex: 0 0 160px; }
  .set-card { padding: 20px 16px; min-height: 160px; }
  .set-card .set-title { font-size: 20px; }
  .app-header { padding: 12px 16px; }
  .app-header .brand-sub { display: none; }
  .exam-nav { padding: 10px 14px; }
  .rank-table th, .rank-table td { padding: 8px 10px; font-size: 13px; }
}
@media (max-width: 420px) {
  .set-grid { gap: 10px; }
  .set-grid > .set-card { flex: 0 0 100%; max-width: 280px; }
  .set-card { min-height: 130px; padding: 18px 16px; }
  .set-card .set-title { font-size: 22px; }
}

/* ── 접근성 ── */
:focus-visible { outline: 2px solid var(--c-accent); outline-offset: 2px; border-radius: 6px; }
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}

/* ── KaTeX ── */
.katex { font-size: 1.05em; }
.question-body .katex { font-size: 1.1em; }