:root {
  color-scheme: light;
  --ink: #0b1220;
  --muted: #5e6a7d;
  --line: #dce3ee;
  --panel: #ffffff;
  --canvas: #f4f7fb;
  --primary: #2563eb;
  --primary-deep: #1d4ed8;
  --primary-soft: #eaf1ff;
  --success: #0f9f72;
  --success-soft: #e8f8f2;
  --warning: #c26a11;
  --warning-soft: #fff5e8;
  --shadow: 0 20px 55px rgba(11, 18, 32, 0.10);
  --radius-xl: 28px;
  --radius-lg: 20px;
  --radius-md: 14px;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  min-width: 320px;
  background:
    radial-gradient(circle at 15% -5%, rgba(37, 99, 235, .12), transparent 28rem),
    var(--canvas);
  color: var(--ink);
  font-family: Inter, Pretendard, "Noto Sans KR", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

button, textarea, input { font: inherit; }
button { -webkit-tap-highlight-color: transparent; }
button:focus-visible, textarea:focus-visible { outline: 3px solid rgba(37, 99, 235, .25); outline-offset: 2px; }

.page-shell {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 28px 0 36px;
}

/* 체험 중에는 학습 흐름이 우선이므로 조용하게 둔다. */
.home-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 40px;
  margin-bottom: 14px;
  padding: 8px 12px 8px 0;
  border-radius: 8px;
  color: #64748b;
  font-size: .86rem;
  font-weight: 800;
  text-decoration: none;
  transition: color .15s ease;
}
.home-link:hover { color: var(--primary); }
.home-link:focus-visible { outline: 3px solid rgba(37, 99, 235, .25); outline-offset: 2px; }

.hero { max-width: 930px; margin-bottom: 20px; }
.eyebrow {
  color: var(--primary);
  font-size: .78rem;
  font-weight: 800;
  letter-spacing: .13em;
}

/* 체험은 조작하는 작업 화면이므로 Home보다 제목을 작게 잡아
   도구 영역에 세로 공간을 넘긴다. */
h1 {
  margin: 8px 0 10px;
  font-size: clamp(1.9rem, 3.2vw, 2.8rem);
  line-height: 1.06;
  letter-spacing: -.05em;
}

.hero-copy {
  max-width: 780px;
  margin: 0;
  color: var(--muted);
  font-size: clamp(1rem, 1.7vw, 1.2rem);
  line-height: 1.7;
}

.learning-path {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-top: 20px;
}

.step {
  min-width: 0;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255, 255, 255, .72);
  color: #8792a4;
  font-size: .8rem;
  text-align: left;
}
button.step { cursor: pointer; }
button.step:hover { border-color: #b9c9e4; background: #fff; }

.step span {
  display: grid;
  width: 26px;
  height: 26px;
  flex: 0 0 26px;
  place-items: center;
  border-radius: 50%;
  background: #e8edf5;
  font-weight: 800;
}

.step strong { overflow: hidden; text-overflow: ellipsis; }
.step.available { color: #546176; }
.step.active { border-color: #a9c5ff; color: var(--primary); background: var(--primary-soft); }
.step.active span { color: #fff; background: var(--primary); }
.step.locked { opacity: .66; }

.experience.hidden { display: none; }

.tool-card {
  padding: clamp(18px, 2.2vw, 26px);
  border: 1px solid rgba(203, 213, 225, .8);
  border-radius: var(--radius-xl);
  background: rgba(255, 255, 255, .94);
  box-shadow: var(--shadow);
}

.tool-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-bottom: 17px;
}

.section-kicker { margin: 0 0 5px; color: var(--primary); font-size: .8rem; font-weight: 800; }
h2 { margin: 0; font-size: clamp(1.25rem, 2vw, 1.7rem); letter-spacing: -.03em; }

.mode-toggle { display: inline-flex; align-items: center; gap: 9px; cursor: pointer; color: #344054; font-size: .9rem; font-weight: 700; user-select: none; }
.mode-toggle input { position: absolute; opacity: 0; pointer-events: none; }
.toggle-ui { width: 44px; height: 26px; padding: 3px; border-radius: 999px; background: #d4dbe6; transition: .2s ease; }
.toggle-ui::after { content: ""; display: block; width: 20px; height: 20px; border-radius: 50%; background: #fff; box-shadow: 0 2px 6px rgba(0,0,0,.16); transition: .2s ease; }
.mode-toggle input:checked + .toggle-ui { background: var(--primary); }
.mode-toggle input:checked + .toggle-ui::after { transform: translateX(18px); }
.mode-toggle input:focus-visible + .toggle-ui { outline: 3px solid rgba(37, 99, 235, .24); outline-offset: 2px; }

.mode-panel.hidden { display: none; }
.hash-panel { padding: clamp(16px, 1.9vw, 22px); border: 1px solid var(--line); border-radius: var(--radius-lg); background: #fbfcfe; }
.compact-panel { min-width: 0; }

.field-heading, .hash-heading { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.field-heading label, .label, .block-field-label { font-size: .9rem; font-weight: 800; color: #334155; }
.text-button { border: 0; background: transparent; color: var(--primary); font-size: .83rem; font-weight: 800; cursor: pointer; padding: 7px 0; }
.text-button:hover { text-decoration: underline; }

textarea {
  width: 100%;
  min-height: 84px;
  margin-top: 9px;
  padding: 13px 15px;
  resize: vertical;
  border: 1.5px solid #cbd5e1;
  border-radius: var(--radius-md);
  outline: none;
  background: #fff;
  color: var(--ink);
  font-size: 1.05rem;
  line-height: 1.6;
  transition: border-color .15s ease, box-shadow .15s ease;
}
.compact-panel textarea { min-height: 76px; }
textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 4px rgba(37, 99, 235, .10); }

.flow-arrow { display: flex; align-items: center; justify-content: center; gap: 12px; padding: 11px 0; color: #94a3b8; font-size: 1.05rem; }
.flow-arrow span { color: var(--primary); font-size: .75rem; font-weight: 900; letter-spacing: .08em; }

.hash-heading { margin-bottom: 10px; }
.hash-heading > div { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.length-badge { padding: 4px 8px; border-radius: 999px; background: var(--success-soft); color: var(--success); font-size: .72rem; font-weight: 800; }
.copy-button, .secondary-button, .primary-button {
  border: 0;
  border-radius: 10px;
  font-weight: 800;
  cursor: pointer;
  transition: transform .15s ease, background .15s ease, box-shadow .15s ease;
}
.copy-button { min-height: 38px; padding: 8px 13px; background: #e8eef8; color: #344054; font-size: .8rem; }
.copy-button:hover { background: #dfe7f3; }
.copy-button.small { min-height: 34px; padding: 6px 11px; }
.copy-button:active, .secondary-button:active, .primary-button:active { transform: translateY(1px); }

.hash-output {
  display: block;
  min-height: 60px;
  padding: 15px 16px;
  overflow-wrap: anywhere;
  border-radius: var(--radius-md);
  background: #0b1220;
  color: #dce8ff;
  font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: clamp(.88rem, 1.6vw, 1.05rem);
  line-height: 1.8;
  letter-spacing: .02em;
}
/* 비교 모드는 폭이 절반이라 Hash가 여러 줄로 감긴다. 최소 높이를 따로 둔다. */
.small-output { min-height: 92px; font-size: .9rem; }

.compare-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.comparison-summary {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-top: 16px;
  padding: 16px 18px;
  border: 1px solid #b9d8cd;
  border-radius: var(--radius-md);
  background: var(--success-soft);
}
.summary-icon { display: grid; width: 38px; height: 38px; flex: 0 0 38px; place-items: center; border-radius: 50%; background: #fff; color: var(--success); font-size: 1.25rem; font-weight: 900; }
.comparison-summary strong { font-size: .95rem; }
.comparison-summary p { margin: 3px 0 0; color: #4d675e; font-size: .83rem; line-height: 1.5; }
.comparison-summary.same { border-color: #cbd5e1; background: #f1f5f9; }
.comparison-summary.same .summary-icon { color: #64748b; }
.comparison-summary.same p { color: #64748b; }

.lesson-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 14px; margin-top: 14px; }
.lesson-grid article { padding: 17px 18px; border: 1px solid var(--line); border-radius: var(--radius-lg); background: rgba(255,255,255,.72); }
.lesson-number { color: var(--primary); font-size: .73rem; font-weight: 900; letter-spacing: .08em; }
.lesson-grid h3 { margin: 8px 0 7px; font-size: 1rem; letter-spacing: -.02em; }
.lesson-grid p { margin: 0; color: var(--muted); font-size: .86rem; line-height: 1.6; }

.next-step-row { display: flex; justify-content: flex-end; margin-top: 14px; }
.primary-button { padding: 12px 17px; background: var(--primary); color: #fff; box-shadow: 0 8px 18px rgba(37, 99, 235, .22); }
.primary-button:hover { background: var(--primary-deep); }
.secondary-button { padding: 10px 14px; background: #eef2f7; color: #475569; }
.secondary-button:hover { background: #e3e9f1; }

/* STEP 2: Block */
.block-tool { overflow: hidden; }
.block-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.28fr) minmax(330px, .72fr);
  gap: 22px;
  align-items: stretch;
}

.block-card {
  position: relative;
  padding: clamp(19px, 2.6vw, 28px);
  border: 1.5px solid #b9c8dd;
  border-radius: 22px;
  background: linear-gradient(180deg, #fbfdff 0%, #f6f9fd 100%);
  transition: border-color .2s ease, box-shadow .2s ease;
}
.block-card.changed {
  border-color: #e4a75f;
  box-shadow: 0 0 0 4px rgba(194, 106, 17, .08);
}

.block-card-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 16px; margin-bottom: 21px; }
.block-label { color: var(--primary); font-size: .68rem; font-weight: 900; letter-spacing: .13em; }
.block-card h3 { margin: 4px 0 0; font-size: clamp(1.55rem, 2.6vw, 2.1rem); letter-spacing: -.04em; }
.state-badge { padding: 6px 10px; border-radius: 999px; font-size: .74rem; font-weight: 800; white-space: nowrap; }
.state-badge.stable { background: var(--success-soft); color: var(--success); }
.state-badge.changed { background: var(--warning-soft); color: var(--warning); }

.block-fields { display: grid; gap: 13px; }
.block-field {
  min-width: 0;
  padding: 14px 15px;
  border: 1px solid #d9e2ee;
  border-radius: 14px;
  background: rgba(255,255,255,.86);
}
.block-field.editable-field { padding: 15px; border-color: #c8d5e6; }
.block-field textarea { min-height: 96px; margin-top: 9px; }
.block-value { display: block; margin-top: 8px; color: #132036; font-size: .94rem; font-weight: 750; line-height: 1.55; overflow-wrap: anywhere; }
.block-value.mono { font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace; font-size: .82rem; font-weight: 600; color: #44546a; }
.field-help { display: block; margin-top: 7px; color: #7b8799; font-size: .74rem; line-height: 1.5; }
.mini-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 13px; }
.mini-fields .block-value { font-size: 1.08rem; }

.block-hash-side { min-width: 0; display: grid; grid-template-columns: auto minmax(0, 1fr); gap: 13px; align-items: center; }
.block-flow { display: flex; flex-direction: column; align-items: center; justify-content: center; color: #9aa8ba; }
.flow-line { width: 1px; height: 38px; background: #cbd5e1; }
.flow-chip { margin: 8px 0; padding: 6px 7px; border-radius: 7px; background: var(--primary-soft); color: var(--primary); font-size: .66rem; font-weight: 900; letter-spacing: .06em; writing-mode: vertical-rl; transform: rotate(180deg); }
.flow-arrow-right { font-size: 1.4rem; color: var(--primary); }

.result-card {
  min-width: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 20px;
  border: 1px solid #cdd8e8;
  border-radius: 20px;
  background: #fff;
}
.block-hash-output { min-height: 148px; display: flex; align-items: center; }
.block-hash-output.flash { animation: hashFlash .45s ease; }
@keyframes hashFlash {
  0% { box-shadow: inset 0 0 0 999px rgba(37, 99, 235, .17); }
  100% { box-shadow: inset 0 0 0 999px rgba(37, 99, 235, 0); }
}
.block-insight {
  display: flex;
  gap: 11px;
  margin-top: 14px;
  padding: 13px 14px;
  border-radius: 13px;
  background: var(--success-soft);
  color: #345d50;
}
.block-insight.changed { background: var(--warning-soft); color: #78502a; }
.insight-icon { display: grid; width: 28px; height: 28px; flex: 0 0 28px; place-items: center; border-radius: 50%; background: #fff; color: var(--success); font-weight: 900; }
.block-insight.changed .insight-icon { color: var(--warning); }
.block-insight strong { display: block; color: #223b33; font-size: .86rem; line-height: 1.4; }
.block-insight.changed strong { color: #67421f; }
.block-insight p { margin: 3px 0 0; font-size: .76rem; line-height: 1.5; }

.bridge-note {
  display: flex;
  align-items: flex-start;
  gap: 14px;
  margin-top: 18px;
  padding: 18px 20px;
  border: 1px dashed #a9bdd8;
  border-radius: var(--radius-lg);
  background: rgba(234, 241, 255, .58);
}
.bridge-icon { display: grid; width: 36px; height: 36px; flex: 0 0 36px; place-items: center; border-radius: 50%; background: #fff; color: var(--primary); font-weight: 900; }
.bridge-note strong { font-size: .94rem; }
.bridge-note p { margin: 4px 0 0; color: #5d6d83; font-size: .84rem; line-height: 1.6; }

.privacy-note { display: flex; align-items: center; gap: 8px; margin: 20px 3px 0; color: #738095; font-size: .78rem; line-height: 1.5; }
.privacy-note span { color: var(--success); font-size: .55rem; }

.toast {
  position: fixed;
  left: 50%;
  bottom: 24px;
  z-index: 20;
  transform: translate(-50%, 16px);
  padding: 11px 15px;
  border-radius: 10px;
  background: #111827;
  color: #fff;
  font-size: .84rem;
  opacity: 0;
  pointer-events: none;
  transition: .2s ease;
  box-shadow: 0 12px 30px rgba(0,0,0,.22);
}
.toast.show { opacity: 1; transform: translate(-50%, 0); }

@media (max-width: 900px) {
  .block-layout { grid-template-columns: 1fr; }
  .block-hash-side { grid-template-columns: 1fr; gap: 10px; }
  .block-flow { flex-direction: row; min-height: 30px; }
  .flow-line { width: 36px; height: 1px; }
  .flow-chip { margin: 0 8px; writing-mode: horizontal-tb; transform: none; }
  .flow-arrow-right { transform: rotate(90deg); }
  .block-hash-output { min-height: 104px; }
}

@media (max-width: 760px) {
  .page-shell { width: min(100% - 24px, 1120px); padding-top: 14px; }
  .home-link { margin-bottom: 8px; }
  .learning-path { grid-template-columns: repeat(4, max-content); overflow-x: auto; padding-bottom: 3px; scrollbar-width: none; }
  .learning-path::-webkit-scrollbar { display: none; }
  .step { padding: 9px 11px; }
  .step span { width: 23px; height: 23px; flex-basis: 23px; }
  .tool-toolbar { align-items: flex-start; }
  .compare-grid, .lesson-grid { grid-template-columns: 1fr; }
  .small-output { min-height: 94px; }
}

@media (max-width: 520px) {
  h1 { font-size: 2.2rem; }
  .hero-copy { font-size: .96rem; }
  .tool-card { border-radius: 22px; }
  .tool-toolbar { flex-direction: column; gap: 15px; }
  .mode-toggle, .block-toolbar .secondary-button { align-self: flex-end; }
  .hash-panel { padding: 16px; }
  textarea { min-height: 104px; font-size: 1rem; }
  .hash-output { min-height: 112px; padding: 15px; font-size: .84rem; line-height: 1.75; }
  .comparison-summary { align-items: flex-start; }
  .block-card { padding: 17px; }
  .block-card-header { align-items: center; }
  .mini-fields { grid-template-columns: 1fr 1fr; }
  .block-field { padding: 13px; }
  .block-field.editable-field { padding: 13px; }
  .block-value.mono { font-size: .76rem; }
  .result-card { padding: 16px; }
  .bridge-note { padding: 16px; }
  .next-step-row .primary-button { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .001ms !important; animation-duration: .001ms !important; }
}

/* STEP 2 v2: 여러 거래를 하나의 Block으로 보여주는 교육용 UI */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.block-definition {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 6px 10px;
  margin: -4px 0 20px;
  padding: 12px 14px;
  border-radius: 12px;
  background: var(--primary-soft);
  color: #4f6484;
  font-size: .8rem;
  line-height: 1.5;
}
.block-definition strong { color: var(--primary-deep); font-size: .86rem; }

.block-section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 14px;
  margin-bottom: 10px;
}
.block-section-kicker {
  display: block;
  margin-bottom: 2px;
  color: var(--primary);
  font-size: .66rem;
  font-weight: 900;
  letter-spacing: .12em;
}
.block-section-heading h4 {
  margin: 0;
  font-size: 1rem;
  letter-spacing: -.02em;
}

.transaction-list {
  display: grid;
  gap: 8px;
}
.transaction-row {
  display: grid;
  grid-template-columns: 38px minmax(150px, 1fr) minmax(128px, .72fr);
  align-items: center;
  gap: 10px;
  min-width: 0;
  padding: 11px 12px;
  border: 1px solid #d9e2ee;
  border-radius: 13px;
  background: rgba(255,255,255,.92);
  transition: border-color .18s ease, background .18s ease, box-shadow .18s ease;
}
.transaction-row.focus-transaction { border-color: #c3d2e8; }
.transaction-row.changed {
  border-color: #e5ad68;
  background: #fffaf3;
  box-shadow: 0 0 0 3px rgba(194,106,17,.06);
}
.transaction-index {
  display: grid;
  width: 32px;
  height: 32px;
  place-items: center;
  border-radius: 9px;
  background: #eef3fa;
  color: #64748b;
  font-size: .72rem;
  font-weight: 900;
}
.transaction-row.changed .transaction-index {
  background: var(--warning-soft);
  color: var(--warning);
}
.transaction-route {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
  color: #233149;
  font-size: .9rem;
}
.transaction-route span { color: #91a0b5; }
.transaction-route strong { white-space: nowrap; }

.amount-field {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 6px;
  min-width: 0;
  color: #475569;
  font-size: .85rem;
  font-weight: 700;
}
.amount-field input {
  width: 100%;
  min-width: 0;
  max-width: 120px;
  height: 40px;
  padding: 7px 10px;
  border: 1.5px solid #cbd5e1;
  border-radius: 9px;
  background: #fff;
  color: var(--ink);
  font-size: .95rem;
  font-weight: 800;
  text-align: right;
  font-variant-numeric: tabular-nums;
  outline: none;
}
.amount-field input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,.10);
}

.block-divider {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 18px 0 10px;
  color: #7c899b;
  font-size: .72rem;
  font-weight: 900;
  letter-spacing: .05em;
}
.block-divider::before,
.block-divider::after {
  content: "";
  height: 1px;
  flex: 1;
  background: #dce4ef;
}
.block-meta-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(150px, .32fr);
  gap: 10px;
}
.nonce-field .block-value { font-size: 1.08rem; }

@media (max-width: 760px) {
  .block-section-heading { align-items: flex-start; }
  .transaction-row { grid-template-columns: 34px minmax(115px, 1fr) minmax(110px, .7fr); }
  .transaction-route { gap: 7px; }
  .block-meta-grid { grid-template-columns: 1fr; }
}

@media (max-width: 520px) {
  .block-definition { align-items: flex-start; flex-direction: column; }
  .block-section-heading { flex-direction: column; gap: 3px; }
  .block-section-heading .text-button { align-self: flex-end; }
  .transaction-row {
    grid-template-columns: 32px minmax(0, 1fr);
    gap: 8px 9px;
    padding: 10px;
  }
  .transaction-index { grid-row: span 2; }
  .transaction-route { font-size: .86rem; }
  .amount-field { justify-content: flex-start; }
  .amount-field input { max-width: 132px; text-align: left; }
}

/* STEP 3: Chain */
.chain-toolbar { margin-bottom: 16px; }
.chain-status {
  display: flex;
  align-items: center;
  gap: 13px;
  margin-bottom: 16px;
  padding: 14px 16px;
  border: 1px solid #b9d8cd;
  border-radius: 14px;
  background: var(--success-soft);
  transition: .2s ease;
}
.chain-status.broken { border-color: #efc28f; background: var(--warning-soft); }
.chain-status-icon {
  display: grid;
  width: 34px;
  height: 34px;
  flex: 0 0 34px;
  place-items: center;
  border-radius: 50%;
  background: #fff;
  color: var(--success);
  font-weight: 900;
}
.chain-status.broken .chain-status-icon { color: var(--warning); }
.chain-status strong { font-size: .94rem; }
.chain-status p { margin: 2px 0 0; color: #557166; font-size: .8rem; line-height: 1.5; }
.chain-status.broken p { color: #795b3c; }

.chain-formula {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin: 0 0 20px;
  padding: 10px 12px;
  border-radius: 12px;
  background: #f5f8fc;
  color: #5b6a7f;
  font-size: .76rem;
  font-weight: 800;
  text-align: center;
  flex-wrap: wrap;
}
.chain-formula span { padding: 5px 8px; border-radius: 7px; background: #fff; border: 1px solid #dfe7f1; }
.chain-formula b { color: var(--success); font-size: 1rem; }
.chain-formula i { margin: 0 3px; color: #99a5b6; font-style: normal; font-weight: 600; }

.chain-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 74px minmax(0, 1fr) 74px minmax(0, 1fr);
  gap: 10px;
  align-items: center;
}
.chain-block {
  min-width: 0;
  padding: 16px;
  border: 1.5px solid #b9c8dd;
  border-radius: 18px;
  background: linear-gradient(180deg, #fbfdff 0%, #f6f9fd 100%);
  transition: border-color .2s ease, box-shadow .2s ease, opacity .2s ease;
}
.chain-block.changed { border-color: #e1a45f; box-shadow: 0 0 0 4px rgba(194,106,17,.06); }
.chain-block.broken { border-color: #e49062; box-shadow: 0 0 0 4px rgba(194,80,17,.07); }
.chain-block.downstream { border-color: #e5b88a; opacity: .84; }
.chain-block-head { display: flex; justify-content: space-between; gap: 10px; align-items: flex-start; margin-bottom: 13px; }
.chain-block h3 { margin: 2px 0 0; font-size: 1.28rem; letter-spacing: -.03em; }
.chain-badge { padding: 5px 8px; border-radius: 999px; font-size: .68rem; font-weight: 900; white-space: nowrap; }
.chain-badge.ok { color: var(--success); background: var(--success-soft); }
.chain-badge.changed, .chain-badge.downstream { color: var(--warning); background: var(--warning-soft); }
.chain-badge.broken { color: #b45309; background: #ffedd5; }
.chain-data-title { display: flex; align-items: center; justify-content: space-between; min-height: 28px; color: #64748b; font-size: .7rem; font-weight: 900; letter-spacing: .06em; }
.chain-data-title .text-button { font-size: .72rem; padding: 3px 0; }
.chain-transactions { display: grid; gap: 5px; margin: 6px 0 12px; }
.chain-transactions > div { display: flex; align-items: center; justify-content: space-between; gap: 8px; min-width: 0; padding: 8px 9px; border: 1px solid #e1e7ef; border-radius: 9px; background: #fff; font-size: .75rem; }
.chain-transactions span { color: #59677c; white-space: nowrap; }
.chain-transactions strong { color: #1f2c40; font-size: .76rem; white-space: nowrap; }
.editable-chain-tx { border-color: #cdd9ea !important; }
.editable-chain-tx label { display: flex; align-items: center; gap: 3px; font-weight: 800; }
.editable-chain-tx input { width: 68px; height: 30px; padding: 3px 6px; border: 1.3px solid #cbd5e1; border-radius: 7px; text-align: right; font-size: .76rem; font-weight: 800; outline: none; }
.editable-chain-tx input:focus { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,.09); }
.chain-hash-field { margin-top: 7px; padding: 9px 10px; border-radius: 9px; }
.chain-hash-field.previous { background: #f1f5f9; }
.chain-hash-field.current { background: #0b1220; }
.chain-hash-field > span { display: block; margin-bottom: 4px; color: #6c7a8f; font-size: .64rem; font-weight: 900; letter-spacing: .05em; }
.chain-hash-field.current > span { color: #8ca0be; }
.chain-hash-field code { display: block; overflow: hidden; color: #435168; font-family: "SFMono-Regular", Consolas, monospace; font-size: .7rem; font-weight: 700; text-overflow: ellipsis; white-space: nowrap; }
.chain-hash-field.current code { color: #dce8ff; }

.chain-link { display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 3px; color: var(--success); text-align: center; transition: .2s ease; }
.chain-link .link-arrow { font-size: 2rem; line-height: 1; font-weight: 300; }
.chain-link strong { font-size: .66rem; white-space: nowrap; }
.chain-link small { max-width: 74px; color: #658276; font-size: .61rem; line-height: 1.25; }
.chain-link.broken { color: #c25d11; }
.chain-link.broken .link-arrow { transform: rotate(-8deg); }
.chain-link.broken small { color: #a15520; font-weight: 900; }
.chain-link.downstream { color: #c19a6f; opacity: .8; }
.chain-link.downstream small { color: #8c7357; }

.chain-instruction { display: flex; gap: 12px; align-items: flex-start; margin-top: 18px; padding: 14px 16px; border: 1px dashed #adc0dd; border-radius: 14px; background: #f7faff; }
.instruction-number { display: grid; width: 28px; height: 28px; flex: 0 0 28px; place-items: center; border-radius: 50%; background: var(--primary); color: #fff; font-size: .75rem; font-weight: 900; }
.chain-instruction p { margin: 2px 0 0; color: #596a82; font-size: .8rem; line-height: 1.6; }
.chain-instruction strong { color: #233551; }
.bridge-action { align-items: center; }
.bridge-action > div:nth-child(2) { flex: 1; }
.bridge-action .primary-button { flex: 0 0 auto; }

@media (max-width: 980px) {
  .chain-grid { grid-template-columns: 1fr; gap: 8px; }
  .chain-link { flex-direction: row; min-height: 32px; }
  .chain-link .link-arrow { transform: rotate(90deg); }
  .chain-link.broken .link-arrow { transform: rotate(82deg); }
  .chain-link strong { margin-left: 4px; }
  .chain-link small { max-width: none; }
}

@media (max-width: 620px) {
  .chain-formula { justify-content: flex-start; }
  .chain-formula i { width: 100%; text-align: center; }
  .chain-block { padding: 14px; }
  .chain-transactions > div { font-size: .72rem; }
  .chain-status { align-items: flex-start; }
  .bridge-action { align-items: flex-start; flex-wrap: wrap; }
  .bridge-action .primary-button { width: 100%; }
}

/* STEP 4: Proof of Work */
.pow-toolbar { margin-bottom: 16px; }
.pow-goal {
  display: flex;
  align-items: center;
  gap: 13px;
  margin-bottom: 14px;
  padding: 14px 16px;
  border: 1px solid #bfd0ed;
  border-radius: 14px;
  background: #f3f7ff;
}
.pow-goal-icon {
  display: grid;
  width: 38px;
  height: 38px;
  flex: 0 0 38px;
  place-items: center;
  border-radius: 50%;
  background: #fff;
  color: var(--primary);
  font-size: 1.1rem;
  font-weight: 900;
}
.pow-goal span { display: block; margin-bottom: 3px; color: #65758e; font-size: .72rem; font-weight: 800; }
.pow-goal strong { color: #21324d; font-size: .95rem; }
.pow-goal code {
  padding: 3px 7px;
  border-radius: 7px;
  background: #0b1220;
  color: #e8f0ff;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: .9em;
}

.difficulty-control {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 18px;
  padding: 0;
  border: 0;
  flex-wrap: wrap;
}
.difficulty-control legend {
  width: 100%;
  margin-bottom: 7px;
  color: #52627a;
  font-size: .77rem;
  font-weight: 900;
}
.difficulty-control label { cursor: pointer; }
.difficulty-control input { position: absolute; opacity: 0; pointer-events: none; }
.difficulty-control label > span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 38px;
  padding: 7px 11px;
  border: 1px solid #d7e0eb;
  border-radius: 10px;
  background: #fff;
  color: #66748a;
  font-size: .76rem;
  transition: .15s ease;
}
.difficulty-control label > span b { color: #435168; font-size: .78rem; }
.difficulty-control label > span code { font-family: "SFMono-Regular", Consolas, monospace; font-weight: 900; }
.difficulty-control input:checked + span {
  border-color: #9db9f0;
  background: var(--primary-soft);
  color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,.06);
}
.difficulty-control input:checked + span b { color: var(--primary-deep); }
.difficulty-control input:focus-visible + span { outline: 3px solid rgba(37,99,235,.2); outline-offset: 2px; }
.difficulty-control input:disabled + span { opacity: .55; cursor: not-allowed; }
.difficulty-control > p {
  flex: 1 1 280px;
  margin: 0 0 0 6px;
  color: #7a8798;
  font-size: .72rem;
  line-height: 1.45;
}
.difficulty-control > p strong { color: #5b6b82; }

.pow-layout {
  display: grid;
  grid-template-columns: minmax(0, .9fr) minmax(360px, 1.1fr);
  gap: 18px;
  align-items: stretch;
}
.pow-block-card {
  min-width: 0;
  padding: 18px;
  border: 1.5px solid #b9c8dd;
  border-radius: 20px;
  background: linear-gradient(180deg, #fbfdff 0%, #f6f9fd 100%);
  transition: .2s ease;
}
.pow-block-card.mining { border-color: #9bb8eb; box-shadow: 0 0 0 4px rgba(37,99,235,.06); }
.pow-block-card.success { border-color: #82c8b2; box-shadow: 0 0 0 4px rgba(15,159,114,.07); }
.pow-block-card h3 { margin: 2px 0 0; font-size: 1.45rem; letter-spacing: -.035em; }
.pow-transactions { margin-bottom: 14px; }
.pow-block-fields { display: grid; gap: 8px; }
.pow-field {
  min-width: 0;
  padding: 11px 12px;
  border: 1px solid #dce4ef;
  border-radius: 11px;
  background: #fff;
}
.pow-field > span {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 6px;
  color: #69788e;
  font-size: .68rem;
  font-weight: 900;
  letter-spacing: .03em;
}
.pow-field > span small { color: #9aa6b6; font-size: .64rem; font-weight: 700; }
.pow-field code {
  display: block;
  overflow: hidden;
  color: #3d4d65;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: .76rem;
  font-weight: 800;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.nonce-live { background: #f7f9fc; }
.nonce-live > span { margin-bottom: 2px; }
.nonce-live output {
  display: block;
  color: var(--primary-deep);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  font-weight: 900;
  line-height: 1.1;
  font-variant-numeric: tabular-nums;
}
.nonce-live > small { display: block; margin-top: 4px; color: #929fb1; font-size: .68rem; }

.pow-result {
  min-width: 0;
  padding: 18px;
  border: 1px solid #d9e2ee;
  border-radius: 20px;
  background: #fbfcfe;
}
.pow-target-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 14px;
  padding: 10px 12px;
  border-radius: 11px;
  background: #eef3fa;
}
.pow-target-row span { color: #66768e; font-size: .75rem; font-weight: 900; }
.pow-target-row code {
  color: var(--primary-deep);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: .9rem;
  font-weight: 900;
}
.pow-hash-heading { margin-top: 2px; }
.length-badge.pending { background: #eef2f7; color: #6f7d91; }
.length-badge.success { background: var(--success-soft); color: var(--success); }
.pow-hash-output { min-height: 112px; transition: .2s ease; }
.pow-hash-output.working { box-shadow: inset 0 0 0 1px #36517a; }
.pow-hash-output.success { background: #073e33; color: #d9fff3; box-shadow: 0 0 0 3px rgba(15,159,114,.11); }

.pow-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 9px;
  margin: 11px 0;
}
.pow-stats > div {
  padding: 11px 12px;
  border: 1px solid #e0e7f0;
  border-radius: 11px;
  background: #fff;
}
.pow-stats span { display: block; margin-bottom: 3px; color: #7b889a; font-size: .68rem; font-weight: 800; }
.pow-stats strong { color: #26364f; font-size: 1rem; font-variant-numeric: tabular-nums; }

.mine-button {
  width: 100%;
  min-height: 48px;
  border: 0;
  border-radius: 12px;
  background: var(--primary);
  color: #fff;
  font-size: .94rem;
  font-weight: 900;
  cursor: pointer;
  box-shadow: 0 9px 20px rgba(37,99,235,.2);
  transition: .15s ease;
}
.mine-button:hover { background: var(--primary-deep); }
.mine-button:active { transform: translateY(1px); }
.mine-button.mining { background: #44556f; box-shadow: none; }
.mine-button.success { background: var(--success); box-shadow: 0 9px 20px rgba(15,159,114,.18); }

.pow-status {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-top: 11px;
  padding: 11px 12px;
  border: 1px solid #dde5ef;
  border-radius: 11px;
  background: #fff;
}
.pow-status-icon {
  display: grid;
  width: 28px;
  height: 28px;
  flex: 0 0 28px;
  place-items: center;
  border-radius: 50%;
  background: #eef3fa;
  color: #687992;
  font-size: .75rem;
  font-weight: 900;
}
.pow-status strong { color: #34455e; font-size: .78rem; }
.pow-status p { margin: 2px 0 0; color: #7a8798; font-size: .7rem; line-height: 1.45; }
.pow-status.working { border-color: #c8d7ef; background: #f5f8ff; }
.pow-status.working .pow-status-icon { color: var(--primary); background: #fff; animation: powSpin 1s linear infinite; }
.pow-status.success { border-color: #b8dfd1; background: var(--success-soft); }
.pow-status.success .pow-status-icon { color: var(--success); background: #fff; animation: none; }
.pow-status.success strong { color: #166a51; }
.pow-status.success p { color: #4e7568; }
.pow-status.stopped { border-color: #e7d3bd; background: #fff8ef; }
.pow-status.stopped .pow-status-icon { color: var(--warning); background: #fff; }
@keyframes powSpin { to { transform: rotate(360deg); } }

.completion-note {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 18px;
  padding: 16px 18px;
  border: 1px solid #b9d8cd;
  border-radius: 16px;
  background: var(--success-soft);
}
.completion-note > span {
  display: grid;
  width: 34px;
  height: 34px;
  flex: 0 0 34px;
  place-items: center;
  border-radius: 50%;
  background: #fff;
  color: var(--success);
  font-weight: 900;
}
.completion-note strong { color: #205f4d; font-size: .9rem; }
.completion-note p { margin: 3px 0 0; color: #557166; font-size: .8rem; line-height: 1.5; }

@media (max-width: 840px) {
  .pow-layout { grid-template-columns: 1fr; }
}

@media (max-width: 620px) {
  .pow-goal { align-items: flex-start; }
  .difficulty-control > p { flex-basis: 100%; margin: 2px 0 0; }
  .pow-result, .pow-block-card { padding: 14px; }
  .pow-stats { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 430px) {
  .difficulty-control label { flex: 1 1 30%; }
  .difficulty-control label > span { width: 100%; justify-content: center; padding-inline: 7px; }
  .pow-stats { grid-template-columns: 1fr; }
  .pow-target-row { align-items: flex-start; flex-direction: column; gap: 4px; }
}

@media (prefers-reduced-motion: reduce) {
  .pow-status.working .pow-status-icon { animation: none; }
}

@media (max-width: 620px) {
  .learning-path {
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 6px;
    overflow: visible;
  }
  .step {
    justify-content: center;
    gap: 5px;
    padding: 8px 5px;
    font-size: .68rem;
  }
  .step span {
    width: 22px;
    height: 22px;
    flex-basis: 22px;
  }
  .step strong { overflow: visible; text-overflow: clip; }
}

/* STEP 4 v2: 직접 Mining → 자동 Mining */
.manual-mining {
  margin-bottom: 22px;
  padding: clamp(16px, 2.4vw, 22px);
  border: 1px solid #cdd9e9;
  border-radius: 20px;
  background: linear-gradient(180deg, #fbfdff 0%, #f7faff 100%);
}
.manual-mining-head { margin-bottom: 14px; }
.substep-badge {
  display: inline-flex;
  margin-bottom: 7px;
  padding: 5px 8px;
  border-radius: 999px;
  background: var(--primary-soft);
  color: var(--primary-deep);
  font-size: .68rem;
  font-weight: 900;
  letter-spacing: .04em;
}
.manual-mining-head h3,
.auto-mining-head h3 {
  margin: 0;
  color: #172338;
  font-size: clamp(1.12rem, 2vw, 1.35rem);
  letter-spacing: -.025em;
}
.manual-mining-head p {
  margin: 6px 0 0;
  color: #687890;
  font-size: .82rem;
  line-height: 1.55;
}
.manual-difficulty-control {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  padding: 0;
  border: 0;
  flex-wrap: wrap;
}
.manual-difficulty-control legend {
  width: 100%;
  margin-bottom: 6px;
  color: #52627a;
  font-size: .76rem;
  font-weight: 900;
}
.manual-difficulty-control label { cursor: pointer; }
.manual-difficulty-control input { position: absolute; opacity: 0; pointer-events: none; }
.manual-difficulty-control label > span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  min-height: 40px;
  padding: 8px 12px;
  border: 1px solid #d7e0eb;
  border-radius: 11px;
  background: #fff;
  color: #66748a;
  transition: .15s ease;
}
.manual-difficulty-control label > span b { color: #435168; font-size: .78rem; }
.manual-difficulty-control label > span code {
  min-width: 27px;
  padding: 2px 6px;
  border-radius: 6px;
  background: #f1f5f9;
  color: #34445d;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: .82rem;
  font-weight: 900;
  text-align: center;
}
.manual-difficulty-control input:checked + span {
  border-color: #9db9f0;
  background: var(--primary-soft);
  color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37,99,235,.06);
}
.manual-difficulty-control input:checked + span b { color: var(--primary-deep); }
.manual-difficulty-control input:checked + span code { background: #fff; color: var(--primary-deep); }
.manual-difficulty-control input:focus-visible + span { outline: 3px solid rgba(37,99,235,.2); outline-offset: 2px; }
.manual-difficulty-control > p {
  flex: 1 1 300px;
  margin: 0 0 0 5px;
  color: #758399;
  font-size: .72rem;
  line-height: 1.5;
}
.manual-difficulty-control > p strong { color: #4f6078; }

.manual-mining-grid {
  display: grid;
  grid-template-columns: minmax(0, .84fr) minmax(380px, 1.16fr);
  gap: 16px;
  align-items: stretch;
}
.manual-pow-card,
.manual-pow-result {
  min-width: 0;
  padding: 16px;
  border: 1.5px solid #d5dfeb;
  border-radius: 17px;
  background: #fff;
  transition: .18s ease;
}
.manual-pow-card.success { border-color: #82c8b2; box-shadow: 0 0 0 4px rgba(15,159,114,.06); }
.manual-pow-card h4 { margin: 2px 0 0; font-size: 1.28rem; letter-spacing: -.03em; }
.manual-data-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin: 11px 0 9px;
  padding: 9px 10px;
  border-radius: 10px;
  background: #f4f7fb;
  color: #718097;
  font-size: .7rem;
}
.manual-data-summary strong { color: #40516a; font-size: .72rem; }
.manual-pow-result { background: #fbfcfe; }
.manual-target-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  margin-bottom: 12px;
  padding: 10px 12px;
  border-radius: 11px;
  background: #eef3fa;
}
.manual-target-row > span { color: #66768e; font-size: .73rem; font-weight: 900; }
.manual-target-row strong { color: #334761; font-size: .8rem; }
.manual-target-row code {
  padding: 3px 7px;
  border-radius: 7px;
  background: #0b1220;
  color: #e8f0ff;
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: .9em;
}
.manual-nonce-field { display: block; margin-bottom: 14px; }
.manual-nonce-field > span {
  display: block;
  margin-bottom: 7px;
  color: #4f6077;
  font-size: .78rem;
  font-weight: 900;
}
.manual-nonce-field input {
  width: 100%;
  min-height: 58px;
  padding: 9px 13px;
  border: 1.5px solid #b9c9dc;
  border-radius: 12px;
  outline: none;
  background: #fff;
  color: var(--primary-deep);
  font-family: "SFMono-Regular", Consolas, monospace;
  font-size: clamp(1.45rem, 4vw, 2.05rem);
  font-weight: 900;
  font-variant-numeric: tabular-nums;
  transition: .15s ease;
}
.manual-nonce-field input:focus { border-color: #7ea4e8; box-shadow: 0 0 0 4px rgba(37,99,235,.08); }
.manual-nonce-field small { display: block; margin-top: 6px; color: #8a97a9; font-size: .68rem; line-height: 1.4; }
.manual-pow-status {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-top: 11px;
  padding: 11px 12px;
  border: 1px solid #dde5ef;
  border-radius: 11px;
  background: #fff;
}
.manual-status-icon {
  display: grid;
  width: 28px;
  height: 28px;
  flex: 0 0 28px;
  place-items: center;
  border-radius: 50%;
  background: #eef3fa;
  color: #687992;
  font-size: .75rem;
  font-weight: 900;
}
.manual-pow-status strong { color: #34455e; font-size: .78rem; }
.manual-pow-status p { margin: 2px 0 0; color: #7a8798; font-size: .7rem; line-height: 1.45; }
.manual-pow-status.success { border-color: #b8dfd1; background: var(--success-soft); }
.manual-pow-status.success .manual-status-icon { color: var(--success); background: #fff; }
.manual-pow-status.success strong { color: #166a51; }
.manual-pow-status.success p { color: #4e7568; }

.manual-to-auto {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 11px;
  margin: 4px 0 22px;
  padding: 13px 16px;
  border: 1px dashed #a9bdd8;
  border-radius: 14px;
  background: rgba(234, 241, 255, .5);
}
.manual-to-auto > span { color: var(--primary); font-size: 1.4rem; font-weight: 900; }
.manual-to-auto strong { color: #334963; font-size: .83rem; }
.manual-to-auto p { margin: 3px 0 0; color: #718097; font-size: .72rem; line-height: 1.45; }
.auto-mining { padding-top: 2px; }
.auto-mining-head { margin-bottom: 12px; }

@media (max-width: 840px) {
  .manual-mining-grid { grid-template-columns: 1fr; }
}
@media (max-width: 620px) {
  .manual-mining { padding: 14px; }
  .manual-difficulty-control > p { flex-basis: 100%; margin: 2px 0 0; }
  .manual-pow-card, .manual-pow-result { padding: 13px; }
  .manual-to-auto { align-items: flex-start; }
}
@media (max-width: 430px) {
  .manual-difficulty-control label { flex: 1 1 45%; }
  .manual-difficulty-control label > span { width: 100%; justify-content: center; padding-inline: 7px; }
  .manual-target-row { align-items: flex-start; flex-direction: column; gap: 4px; }
  .manual-data-summary { align-items: flex-start; flex-direction: column; }
}

/* ============================================================
   ReturnToLecture — 강의에서 진입했을 때만 보이는 상단바
   (?return=L06 이 있을 때 app.js 가 hidden 을 해제한다)
   ============================================================ */

.return-bar {
  position: sticky;
  top: 0;
  z-index: 40;
  border-bottom: 1px solid #bfd3f8;
  background: rgba(234, 241, 255, .94);
  backdrop-filter: saturate(150%) blur(8px);
}
.return-bar[hidden] { display: none; }

.return-bar-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  width: min(1120px, calc(100% - 28px));
  margin: 0 auto;
  padding: 9px 0;
}

.return-back,
.return-next {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  min-height: 42px;
  padding: 9px 15px;
  border-radius: 11px;
  font-size: .88rem;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
  transition: background .15s ease, color .15s ease, box-shadow .15s ease;
}

.return-back {
  border: 1px solid transparent;
  color: var(--primary-deep);
}
.return-back:hover { background: rgba(255, 255, 255, .8); }

/* 기본 흐름은 ‘강의 계속하기’다. 되돌아가기보다 시각적으로 앞에 둔다. */
.return-next {
  background: var(--primary);
  color: #fff;
  box-shadow: 0 8px 18px rgba(37, 99, 235, .22);
}
.return-next:hover { background: var(--primary-deep); }

.return-tag {
  flex: 0 1 auto;
  color: #6b7c99;
  font-size: .74rem;
  font-weight: 900;
  letter-spacing: .1em;
  white-space: nowrap;
}

/* 상단바가 보이면 기존 ‘강의 홈’ 링크는 중복이므로 감춘다. */
.has-return-bar .home-link { display: none; }
.has-return-bar .page-shell { padding-top: 20px; }

@media (max-width: 560px) {
  .return-tag { display: none; }
  .return-bar-inner { gap: 8px; }
  .return-back,
  .return-next { padding: 9px 12px; font-size: .84rem; }
}