/* =========================================================
   Physical AI with RoboCo series (book-005 ~ book-010)
   Loaded only by RoboCo series pages, after style.css + book.css.
   Existing book-001 ~ book-004 pages do not load this file.
========================================================= */

:root {
  --rk-charcoal: #171a1f;
  --rk-yellow: #ffd91a;
  --rk-yellow-soft: #fff7cc;
  --rk-accent: #0f3f8f;
  --rk-line: #e5e7eb;
}

/* ---------- header: language link + series line ---------- */
.book-header .back {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 16px;
  align-items: center;
}

.book-header .lang-link {
  display: inline-block;
  padding: 5px 12px;
  border: 1px solid rgba(255, 255, 255, 0.35);
  border-radius: 999px;
  color: #ffffff;
  font-size: 14px;
  font-weight: 800;
}

.book-header .lang-link:hover {
  background: rgba(255, 255, 255, 0.12);
}

.series-line {
  max-width: 980px;
  margin: 18px auto 0;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.series-chip {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 800;
  letter-spacing: 0.02em;
  background: rgba(255, 255, 255, 0.1);
  color: #e5e7eb;
}

.series-chip.code {
  background: var(--rk-yellow);
  color: var(--rk-charcoal);
}

/* ---------- status badges ---------- */
.status-badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 800;
  line-height: 1.4;
  vertical-align: middle;
  background: #e5e7eb;
  color: #374151;
}

.status-badge.upcoming {
  background: var(--rk-yellow-soft);
  color: #6b5200;
  border: 1px solid #f3d65c;
}

.status-badge.verified {
  background: #e8f1ff;
  color: var(--rk-accent);
  border: 1px solid #c7dafc;
}

.status-badge.pending {
  background: #f3f4f6;
  color: #4b5563;
  border: 1px solid #e5e7eb;
}

.intro-status {
  margin: 0 0 14px;
}

/* ---------- sidebar extras ---------- */
.book-sidebar .sidebar-divider {
  margin: 16px 0 10px;
  border-top: 1px solid var(--rk-line);
}

.book-sidebar .sidebar-label {
  margin: 0 0 6px;
  font-size: 13px;
  font-weight: 800;
  color: #6b7280;
}

.new-tab-mark {
  font-size: 0.85em;
  margin-left: 2px;
}

.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;
}

/* ---------- figures (roboco-figure-style SVG) ---------- */
.rk-figure {
  margin: 26px 0;
  padding: 18px;
  background: #ffffff;
  border: 1px solid var(--rk-line);
  border-radius: 14px;
}

.rk-figure a.rk-zoom {
  display: block;
  cursor: zoom-in;
}

.rk-figure img {
  display: block;
  width: 100%;
  height: auto;
}

.rk-figure figcaption {
  margin-top: 12px;
  font-size: 14.5px;
  line-height: 1.7;
  color: #4b5563;
}

.rk-figure figcaption strong {
  color: #111827;
}

.rk-figure .rk-zoom-hint {
  display: inline-block;
  margin-left: 6px;
  font-size: 13px;
  font-weight: 700;
  color: var(--rk-accent);
  white-space: nowrap;
}

/* ---------- step flow chips ---------- */
.rk-flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
  margin: 22px 0;
  padding: 0;
  list-style: none;
}

.rk-flow li {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 15px;
  font-weight: 800;
  color: #111827;
}

.rk-flow li span {
  padding: 8px 12px;
  background: #f9fafb;
  border: 1px solid var(--rk-line);
  border-radius: 10px;
}

.rk-flow li:not(:last-child)::after {
  content: "→";
  color: #9ca3af;
  font-weight: 700;
}

.rk-flow li.is-key span {
  background: var(--rk-yellow-soft);
  border-color: #f3d65c;
}

/* ---------- tables ---------- */
.rk-table-wrap {
  width: 100%;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  margin: 18px 0;
}

.rk-table-wrap .faq-table {
  margin: 0;
}

/* wide tables (4+ columns of code-like values) scroll inside the wrapper on phones */
.rk-table-wrap .faq-table.wide {
  min-width: 600px;
}

.faq-table td code,
.faq-table th code {
  overflow-wrap: anywhere;
}

.rk-video-index td:last-child {
  white-space: normal;
}

.faq-table tr.is-current th,
.faq-table tr.is-current td {
  background: var(--rk-yellow-soft);
}

/* ---------- code ---------- */
.rk-code {
  margin: 20px 0;
  padding: 18px 20px;
  background: #111827;
  color: #e5e7eb;
  border-radius: 12px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  font-family: "D2Coding", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  font-size: 14px;
  line-height: 1.65;
  tab-size: 4;
}

.rk-code code {
  font-family: inherit;
  white-space: pre;
}

.rk-code .c {
  color: #9ca3af;
}

.content-card :not(pre) > code {
  padding: 1px 6px;
  background: #f3f4f6;
  border-radius: 5px;
  font-size: 0.92em;
  font-family: "D2Coding", "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  word-break: normal;
  overflow-wrap: anywhere;
}

.rk-code-caption {
  margin-top: -8px !important;
  font-size: 14px !important;
  color: #6b7280 !important;
}

/* ---------- video ---------- */
.rk-video {
  position: relative;
  width: 100%;
  aspect-ratio: 16 / 9;
  margin: 22px 0 10px;
  border-radius: 14px;
  overflow: hidden;
  background: var(--rk-charcoal);
}

.rk-video iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.rk-video-placeholder {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 20px;
  text-align: center;
  color: #e5e7eb;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 28px 28px;
}

.rk-video-placeholder .vid-id {
  font-family: "D2Coding", "SFMono-Regular", Consolas, monospace;
  font-size: 22px;
  font-weight: 800;
  color: var(--rk-yellow);
}

.rk-video-placeholder p {
  margin: 0;
  color: #d1d5db !important;
  font-size: 15px;
  line-height: 1.6;
}

.rk-video-meta {
  font-size: 14.5px;
  color: #4b5563;
}

/* ---------- cards ---------- */
.rk-card-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin: 24px 0;
}

.rk-card {
  padding: 20px;
  background: #ffffff;
  border: 1px solid var(--rk-line);
  border-radius: 14px;
}

.rk-card h3 {
  margin: 0 0 8px !important;
  font-size: 18px !important;
  color: #111827;
}

.rk-card p {
  margin: 6px 0 0 !important;
  font-size: 15px !important;
  line-height: 1.7 !important;
  color: #374151 !important;
}

.rk-card .rk-card-label {
  display: block;
  margin-bottom: 8px;
  font-size: 12.5px;
  font-weight: 900;
  letter-spacing: 0.06em;
  color: var(--rk-accent);
}

.rk-card.is-strong {
  background: #f9fafb;
}

/* Digital Package items */
.rk-package {
  display: grid;
  gap: 12px;
  margin: 22px 0;
}

.rk-package-item {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 6px 16px;
  align-items: start;
  padding: 16px 18px;
  background: #f9fafb;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
}

.rk-package-item h3 {
  margin: 0 !important;
  font-size: 17px !important;
}

.rk-package-item p {
  grid-column: 1 / -1;
  margin: 0 !important;
  font-size: 15px !important;
  line-height: 1.7 !important;
}

/* PART cards on the book page */
.rk-parts {
  display: grid;
  gap: 12px;
  margin: 24px 0;
  padding: 0;
  list-style: none;
}

.rk-parts li {
  display: grid;
  grid-template-columns: 178px 1fr;
  gap: 14px;
  padding: 16px 18px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #ffffff;
}

.rk-parts .part-tag {
  font-size: 13px;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--rk-accent);
}

.rk-parts .part-tag span {
  display: block;
  font-size: 15px;
  color: #111827;
}

.rk-parts p {
  margin: 0 !important;
  font-size: 15.5px !important;
  line-height: 1.75 !important;
}

.rk-note {
  margin: 22px 0;
  padding: 16px 18px;
  background: #f3f4f6;
  border-radius: 12px;
  font-size: 15px;
  line-height: 1.75;
  color: #374151;
}

.rk-note strong {
  color: #111827;
}

/* in-page anchor list on hub */
.rk-anchor-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.rk-anchor-list li {
  margin: 8px 0 !important;
}

.rk-anchor-list a {
  font-weight: 700 !important;
  font-size: 15px;
}

.rk-section-id {
  scroll-margin-top: 20px;
}

/* Video index */
.rk-video-index td:first-child {
  white-space: nowrap;
  font-family: "D2Coding", "SFMono-Regular", Consolas, monospace;
  font-weight: 700;
}

/* Permanent video URL page (/v/{ID}/) */
.vpage-main {
  max-width: 980px;
  margin: 40px auto;
  padding: 0 24px;
}

.vpage-lang {
  margin-top: 26px;
}

.vpage-lang h2 {
  margin-top: 0;
}

@media (max-width: 900px) {
  .rk-card-grid {
    grid-template-columns: 1fr;
  }

  .rk-parts li {
    grid-template-columns: 1fr;
    gap: 6px;
  }
}

@media (max-width: 800px) {
  .rk-figure {
    padding: 10px;
    margin-left: -6px;
    margin-right: -6px;
  }

  .rk-code {
    font-size: 13px;
    padding: 14px;
  }

  .rk-flow li {
    font-size: 14px;
  }

  .rk-flow li span {
    padding: 6px 10px;
  }

  .vpage-main {
    padding: 0 16px;
  }
}

/* book.css turns .faq-table into a nowrap block on mobile; inside the
   scroll wrapper keep normal table layout so long cells can wrap. */
@media (max-width: 800px) {
  .rk-table-wrap .faq-table {
    display: table;
    white-space: normal;
    overflow: visible;
  }
}

/* ---------- v1.2: video-centric web companion ---------- */
.rk-hub-hero {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 30px;
  align-items: center;
}

.rk-hub-hero img {
  width: 100%;
  border-radius: 10px;
  box-shadow: var(--shadow-cover);
}

.rk-book-link {
  display: inline-block;
  margin-top: 12px;
  padding: 5px 11px;
  border-radius: 999px;
  background: #eef2ff;
  border: 1px solid #c7d2fe;
  color: var(--rk-accent);
  font-size: 13.5px;
  font-weight: 800;
  text-decoration: none;
}

.rk-book-link::before {
  content: "📖 ";
}

.rk-vgrid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin: 24px 0;
}

.rk-vcard {
  display: flex;
  flex-direction: column;
  border: 1px solid var(--rk-line);
  border-radius: 14px;
  overflow: hidden;
  background: #ffffff;
}

.rk-vthumb {
  position: relative;
  aspect-ratio: 16 / 9;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  background-color: var(--rk-charcoal);
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 22px 22px;
  color: #e5e7eb;
  text-align: center;
  padding: 10px;
}

.rk-vthumb::after {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 6px;
  background: var(--rk-yellow);
}

.rk-vthumb .vid-id {
  font-family: "D2Coding", "SFMono-Regular", Consolas, monospace;
  font-weight: 800;
  font-size: 16px;
  color: var(--rk-yellow);
}

.rk-vthumb .play {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.55);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 15px;
  color: rgba(255, 255, 255, 0.8);
}

.rk-vbody {
  padding: 16px 18px 18px;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.rk-vbody h3 {
  margin: 0 0 6px !important;
  font-size: 17.5px !important;
  line-height: 1.45 !important;
  color: #111827 !important;
}

.rk-vbody p {
  margin: 4px 0 !important;
  font-size: 15px !important;
  line-height: 1.7 !important;
  color: #374151 !important;
}

.rk-vbody .watch {
  font-size: 13px !important;
  font-weight: 900;
  letter-spacing: 0.04em;
  color: var(--rk-accent) !important;
  margin-top: 8px !important;
}

.rk-vbody .rk-book-link {
  align-self: flex-start;
  margin-top: auto;
}

.rk-vbody .status-badge {
  align-self: flex-start;
  margin-bottom: 8px;
}

.rk-key-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin: 20px 0;
}

.rk-key {
  padding: 14px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #f9fafb;
}

.rk-key kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 34px;
  height: 34px;
  margin-bottom: 8px;
  border: 1px solid #9ca3af;
  border-bottom-width: 3px;
  border-radius: 7px;
  background: #ffffff;
  font-family: "D2Coding", "SFMono-Regular", Consolas, monospace;
  font-size: 16px;
  font-weight: 800;
  color: #111827;
}

.rk-key strong {
  display: block;
  font-size: 15px;
  color: #111827;
}

.rk-key span {
  display: block;
  margin-top: 4px;
  font-size: 14px;
  line-height: 1.6;
  color: #4b5563;
}

.rk-challenge {
  margin: 18px 0;
  padding: 22px 24px;
  border: 1px solid var(--rk-line);
  border-left: 6px solid var(--rk-yellow);
  border-radius: 0 14px 14px 0;
  background: #ffffff;
}

.rk-challenge h3 {
  margin: 0 0 8px !important;
  font-size: 19px !important;
}

.rk-challenge dl {
  display: grid;
  grid-template-columns: 92px 1fr;
  gap: 6px 12px;
  margin: 12px 0 0;
  font-size: 15px;
  line-height: 1.7;
}

.rk-challenge dt {
  font-weight: 900;
  color: #111827;
}

.rk-challenge dd {
  margin: 0;
  color: #374151;
}

@media (max-width: 900px) {
  .rk-vgrid {
    grid-template-columns: 1fr 1fr;
  }

  .rk-key-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  .rk-hub-hero {
    grid-template-columns: 1fr;
  }

  .rk-hub-hero img {
    max-width: 180px;
  }

  .rk-vgrid {
    grid-template-columns: 1fr;
  }

  .rk-challenge dl {
    grid-template-columns: 1fr;
    gap: 2px;
  }

  .rk-challenge dd {
    margin-bottom: 8px;
  }
}

/* ---------- v1.4: published state, series tracks, course plans ---------- */
.status-badge.new {
  background: #111827;
  color: #ffd91a;
  border: 1px solid #111827;
}

.rk-vthumb iframe,
.rk-video-card iframe {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  border: 0;
}

.rk-vthumb.is-live::after {
  display: none;
}

.rk-video-card {
  margin: 0;
  border-radius: 0;
}

.rk-watch-link {
  margin-top: 6px !important;
}

.rk-dl {
  display: inline-block;
  padding: 7px 14px;
  border-radius: 9px;
  background: #111827;
  color: #ffffff !important;
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
}

.rk-dl::before {
  content: "⬇ ";
}

.rk-buy-hero {
  display: grid;
  grid-template-columns: 110px 1fr;
  gap: 20px;
  align-items: center;
}

.rk-buy-hero img {
  width: 100%;
  border-radius: 6px;
  box-shadow: var(--shadow-cover);
}

.rk-sample-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}

.rk-sample-grid img {
  width: 100%;
  border: 1px solid var(--rk-line);
  border-radius: 8px;
}

.rk-bookchip {
  display: inline-block;
  margin: 2px 2px 2px 0;
  padding: 3px 9px;
  border-radius: 6px;
  border-left: 5px solid var(--chip, #e5e7eb);
  background: #f3f4f6;
  color: #111827 !important;
  font-size: 13.5px;
  font-weight: 800;
  text-decoration: none;
  white-space: nowrap;
}

.rk-bookchip.is-upcoming {
  opacity: 0.6;
}

.rk-bookchip.is-current {
  background: var(--rk-yellow-soft);
  outline: 1px solid #f3d65c;
  opacity: 1;
}

.rk-track {
  margin: 20px 0;
}

.rk-track h3 {
  margin: 0 0 12px !important;
  font-size: 18px !important;
}

.rk-track h3 small {
  margin-left: 8px;
  font-size: 13px;
  font-weight: 700;
  color: #6b7280;
}

.rk-trackgrid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.rk-trackcard {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 16px;
  border: 1px solid var(--rk-line);
  border-top: 6px solid var(--chip, #e5e7eb);
  border-radius: 12px;
  background: #ffffff;
  color: #111827;
  text-decoration: none;
}

.rk-trackcard:hover {
  background: #f9fafb;
}

.rk-trackcard.is-current {
  background: var(--rk-yellow-soft);
}

.rk-trackcard .code {
  font-weight: 900;
  font-size: 16px;
}

.rk-trackcard .cap {
  font-size: 12.5px;
  font-weight: 800;
  letter-spacing: 0.04em;
  color: #6b7280;
}

.rk-trackcard .t {
  font-size: 14.5px;
  line-height: 1.55;
  color: #374151;
}

.rk-trackcard .status-badge {
  align-self: flex-start;
  margin-top: auto;
}

.rk-chiprow {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.rk-chiplink {
  padding: 7px 13px;
  border-radius: 999px;
  border: 1px solid var(--rk-line);
  background: #ffffff;
  color: #111827 !important;
  font-size: 14px;
  font-weight: 800;
  text-decoration: none;
}

.rk-chiplink.is-current {
  background: var(--rk-yellow-soft);
  border-color: #f3d65c;
}

.rk-course {
  margin-top: 34px !important;
  padding-top: 30px !important;
}

.rk-course-title {
  margin: 0 0 14px !important;
  font-size: 23px !important;
}

.rk-course.is-current .rk-course-title::after {
  content: "이 책 포함";
  margin-left: 10px;
  padding: 3px 9px;
  border-radius: 999px;
  background: var(--rk-yellow-soft);
  border: 1px solid #f3d65c;
  font-size: 12.5px;
  vertical-align: middle;
}

html[lang="en"] .rk-course.is-current .rk-course-title::after {
  content: "Includes this book";
}

.rk-schedule th:first-child {
  width: 72px;
  white-space: nowrap;
}

.rk-schedule td:last-child {
  width: 34%;
  color: #4b5563;
  font-size: 14.5px;
}

.rk-launch {
  display: grid;
  grid-template-columns: 140px 1fr;
  gap: 24px;
  align-items: center;
  padding: 24px;
  border: 1px solid var(--rk-line);
  border-left: 6px solid var(--rk-yellow);
  border-radius: 0 16px 16px 0;
  background: #fffdf2;
}

.rk-launch img {
  width: 100%;
  border-radius: 6px;
  box-shadow: var(--shadow-cover);
}

.rk-launch h3 {
  margin: 4px 0 8px !important;
}

@media (max-width: 800px) {
  .rk-trackgrid,
  .rk-sample-grid {
    grid-template-columns: 1fr 1fr;
  }

  .rk-launch {
    grid-template-columns: 90px 1fr;
    padding: 16px;
  }
}

@media (max-width: 520px) {
  .rk-trackgrid {
    grid-template-columns: 1fr;
  }

  .rk-buy-hero {
    grid-template-columns: 80px 1fr;
  }

  .rk-launch {
    grid-template-columns: 1fr;
  }

  .rk-launch img {
    max-width: 120px;
  }
}

/* ---------- v1.5: poster frames, robot previews ---------- */
.rk-video .rk-poster {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  opacity: 0.55;
}

.rk-video.has-poster .rk-video-placeholder {
  background: linear-gradient(180deg, rgba(23, 26, 31, 0.15), rgba(23, 26, 31, 0.75));
}

.rk-video-pair {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
  margin: 22px 0;
}

.rk-video-pair article h3 {
  margin: 14px 0 6px !important;
  font-size: 19px !important;
}

.rk-video-pair .rk-video {
  margin: 0;
}

.rk-robots {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
  margin: 22px 0;
}

.rk-robots figure {
  margin: 0;
  padding: 12px;
  border: 1px solid var(--rk-line);
  border-radius: 14px;
  background: linear-gradient(180deg, #f3f4f6, #ffffff);
  text-align: center;
}

.rk-robots img {
  width: 100%;
  max-width: 320px;
  height: auto;
}

.rk-robots figcaption {
  margin-top: 6px;
  font-size: 14px;
  color: #4b5563;
}

.rk-robots figcaption code {
  font-size: 12.5px;
}

@media (max-width: 800px) {
  .rk-video-pair {
    grid-template-columns: 1fr;
  }
}

/* ===== v1.6 — Digital Package page, video links, record sheets ===== */
.intro-cta a[hidden],
[hidden] {
  display: none !important;
}

.rk-vlinks {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 10px;
  margin: 14px 0 0;
}

.rk-vlinks a {
  display: grid;
  gap: 3px;
  padding: 12px 14px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #f9fafb;
  color: #111827;
  text-decoration: none;
}

.rk-vlinks a:hover,
.rk-vlinks a:focus-visible {
  border-color: #111827;
}

.rk-vlinks .vid-id {
  font-family: Consolas, Monaco, monospace;
  font-size: 12px;
  font-weight: 800;
  color: var(--rk-accent);
}

.rk-vlinks small {
  color: #4b5563;
  font-size: 13px;
  line-height: 1.5;
}

.rk-vcount {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.rk-vcount a {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border: 1px solid var(--rk-line);
  border-radius: 10px;
  color: #111827;
  font-size: 14px;
  text-decoration: none;
}

.rk-steps {
  display: grid;
  gap: 10px;
  margin: 18px 0;
  padding: 0;
  list-style: none;
  counter-reset: rkstep;
}

.rk-steps li {
  counter-increment: rkstep;
  display: grid;
  grid-template-columns: 34px 1fr auto;
  gap: 4px 12px;
  align-items: center;
  padding: 12px 14px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #f9fafb;
}

.rk-steps li::before {
  content: counter(rkstep);
  grid-row: 1 / span 2;
  display: grid;
  place-items: center;
  width: 30px;
  height: 30px;
  border-radius: 50%;
  background: var(--rk-yellow);
  color: var(--rk-charcoal);
  font-weight: 800;
}

.rk-steps li span {
  grid-column: 2 / -1;
  color: #4b5563;
  font-size: 14px;
}

.rk-dlcards {
  display: grid;
  gap: 14px;
  margin: 16px 0;
}

.rk-dlcard {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 18px;
  align-items: start;
  padding: 16px;
  border: 1px solid var(--rk-line);
  border-radius: 14px;
}

.rk-dlcard img {
  width: 100%;
  height: auto;
  border-radius: 10px;
  background: #f3f4f6;
}

.rk-dlcard h3 {
  margin: 0 0 4px !important;
}

.rk-dlcard p {
  margin: 0 0 6px !important;
}

.rk-files,
.rk-tree ul {
  margin: 6px 0 0;
  padding-left: 18px;
}

.rk-files li,
.rk-tree li {
  margin: 3px 0;
  overflow-wrap: anywhere;
}

.rk-files small,
.rk-tree small {
  color: #6b7280;
}

.rk-tree {
  margin: 14px 0;
  padding: 14px 16px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #f9fafb;
  font-size: 15px;
}

.rk-tree > p {
  margin: 0 !important;
}

.rk-sheet-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin: 16px 0;
}

.rk-sheet-grid figure {
  margin: 0;
}

.rk-sheet-grid img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid #d1d5db;
  border-radius: 6px;
  box-shadow: 0 2px 8px rgba(17, 24, 39, 0.08);
}

.rk-sheet-grid figcaption {
  margin-top: 6px;
  color: #374151;
  font-size: 13px;
  text-align: center;
}

.rk-hash {
  display: inline-block;
  max-width: 100%;
  font-size: 12px !important;
  overflow-wrap: anywhere;
  word-break: break-all;
}

@media (max-width: 760px) {
  .rk-vlinks,
  .rk-sheet-grid {
    grid-template-columns: 1fr;
  }

  .rk-sheet-grid img {
    max-width: 320px;
    margin: 0 auto;
  }

  .rk-dlcard {
    grid-template-columns: 1fr;
  }

  .rk-dlcard img {
    max-width: 220px;
  }

  .rk-steps li {
    grid-template-columns: 34px 1fr;
  }

  .rk-steps li .rk-dl {
    grid-column: 2;
    justify-self: start;
  }
}

/* ===== v1.7 — web-only explanatory images (idea-generation techniques) ===== */
.rk-webfig {
  padding: 14px;
}

.rk-webfig img {
  border-radius: 6px;
}

.rk-tech {
  display: inline-block;
  margin-right: 6px;
  padding: 1px 9px;
  border-radius: 999px;
  background: var(--rk-yellow-soft);
  border: 1px solid #efe39a;
  color: #111827;
  font-size: 12.5px;
  font-weight: 800;
  vertical-align: 1px;
}

@media (max-width: 760px) {
  .rk-webfig {
    padding: 8px;
  }
}

/* ===== v1.8 — two comment editions of the start file + library ===== */
.rk-editions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin: 16px 0 10px;
}

.rk-edition {
  padding: 14px 16px;
  border: 1px solid var(--rk-line);
  border-radius: 12px;
  background: #ffffff;
}

.rk-edition.is-primary {
  border-color: #111827;
  background: var(--rk-yellow-soft);
}

.rk-edition h3 {
  margin: 0 0 8px !important;
  font-size: 16px !important;
}

.rk-edition p {
  margin: 0 0 6px !important;
  font-size: 14.5px !important;
  overflow-wrap: anywhere;
}

@media (max-width: 760px) {
  .rk-editions {
    grid-template-columns: 1fr;
  }
}

/* v1.9 — two code editions (_kr / _en) side by side in the practice-files card */
.rk-dl-pair {
  grid-column: 1 / -1;
  grid-row: 3;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.rk-dl code {
  background: transparent !important;
  color: inherit !important;
  padding: 0 !important;
  font-size: 13px;
  font-weight: 700;
}

/* ---------- v1.13: live players inside comparison / failure cards ---------- */
.rk-vcard > .rk-video {
  margin: 0;
  border-radius: 0;
}

.rk-vcard > .rk-watch-link {
  padding: 0 18px;
  margin: 12px 0 0 !important;
}

/* ---------- v1.14: desktop reading width (PC only, ≥ 1024px) ----------
   style.css caps .layout at 1100px but a later shared rule resets it to
   max-width: 100%, so on wide monitors text, videos and figures stretched
   across the whole window. Here the book pages get a centred 1280px frame:
   240px sidebar + 32px gap + 960px content card (896px inside the padding).
   A 16:9 video is then at most 896 × 504 and fits in one screen; lines of
   body text stay around 55 Korean characters. The header uses the same
   frame so its title lines up with the sidebar. Mobile/tablet (< 1024px)
   keep the current layout unchanged. Scoped to series-roboco.css, which only
   book-005–010 load, so book-001–004 are not affected. */
@media (min-width: 1024px) {
  .layout {
    max-width: 1280px;
    margin-left: auto;
    margin-right: auto;
  }

  body:has(> .layout) .book-header .back,
  body:has(> .layout) .book-header h1,
  body:has(> .layout) .book-header > p,
  body:has(> .layout) .book-header .series-line {
    max-width: 1232px;
  }
}