/* ===== POST LAYOUT ===== */
.post-layout {
  display: grid;
  grid-template-columns: 1fr 240px;
  gap: 3.5rem;
  align-items: start;
}

/* ===== BREADCRUMB ===== */
.breadcrumb { margin-bottom: 2rem; }
.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: .4rem;
  list-style: none;
  padding: 0;
  font-size: 0.875rem;
  color: var(--muted);
}
.breadcrumb__item a {
  color: var(--muted);
  transition: color .2s;
}
.breadcrumb__item a:hover { color: var(--green-deep); }
.breadcrumb__item:not(:last-child)::after {
  content: '>';
  margin-left: .25rem;
  color: var(--muted);
}
.breadcrumb__item[aria-current="page"] {
  color: var(--fg);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  max-width: 30ch;
}

/* ===== TABLE OF CONTENTS ===== */
.toc {
  background: var(--section-bg);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1.5rem 1.75rem;
  margin-bottom: 2.5rem;
}
.toc__heading {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-bottom: .75rem;
}
.toc__list {
  padding-left: 1.25rem;
  margin: 0;
}
.toc__list li {
  margin-bottom: .5rem;
  font-size: 0.875rem;
  line-height: 1.7;
}
.toc__list a {
  color: var(--fg);
  transition: color .2s;
}
.toc__list a:hover { color: var(--green-deep); }

/* ===== CODE COPY BUTTON ===== */
.code-copy {
  position: absolute;
  top: .5rem;
  right: .5rem;
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 4px 10px;
  font-size: 0.75rem;
  color: var(--muted);
  cursor: pointer;
  opacity: 0;
  transition: opacity .2s, color .2s;
  z-index: 20;
}
div.code-toolbar:hover .code-copy { opacity: 1; }
.code-copy:hover { color: var(--green-deep); }
.code-copy--done { color: var(--green-deep); }

/* Prism.jsツールバー（言語名を左上に常時表示） */
div.code-toolbar { position: relative; }
div.code-toolbar > pre { padding-top: 2.2rem !important; }
div.code-toolbar > .toolbar {
  top: 0 !important;
  right: auto !important;
  left: 0 !important;
  opacity: 1 !important;
  margin: 0;
  padding: 0;
}
div.code-toolbar > .toolbar .toolbar-item {
  margin: 0;
  padding: 0;
}
div.code-toolbar > .toolbar .toolbar-item span {
  display: block;
  background: var(--green);
  color: #fff;
  font-size: 0.68rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: .25rem .5rem !important;
  border-radius: 0 0 4px 0;
  box-shadow: none;
  cursor: default;
  margin: 0;
}

/* ===== BACK LINK ===== */
.back-link {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  font-size: 0.875rem;
  color: var(--muted);
  margin-bottom: 2.5rem;
  transition: color .2s, transform .2s;
}
.back-link svg {
  transition: transform .2s;
}
.back-link:hover {
  color: var(--green-deep);
}
.back-link:hover svg {
  transform: translateX(-3px);
}

/* ===== ACCENT BAR ===== */
.post__accent {
  width: 2.5rem;
  height: 4px;
  border-radius: 2px;
  margin-bottom: 1.5rem;
}
.post__accent--green  { background: var(--green); }
.post__accent--yellow { background: var(--yellow); }
.post__accent--sand   { background: var(--sand); }

/* ===== POST META ===== */
.post__meta {
  display: flex;
  align-items: center;
  gap: .75rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}
.post__meta-item {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  font-size: 0.875rem;
  color: var(--muted);
}

/* ===== POST TITLE ===== */
.post__title {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 500;
  line-height: 1.75;
  letter-spacing: 0.02em;
  color: var(--fg);
  margin-bottom: .75rem;
}
.post__title-tags {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  margin-bottom: 2rem;
}

/* ===== POST BODY ===== */
.post__body {
  font-family: var(--font-heading);
  font-size: 1rem;
  line-height: 2;
  letter-spacing: 0.02em;
  color: var(--fg);
  max-width: 38em;
}

.post__body p {
  margin-bottom: 1.6rem;
}

.post__body h2 {
  font-family: var(--font-heading);
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.7;
  letter-spacing: 0.02em;
  color: var(--fg);
  margin-top: 3rem;
  margin-bottom: 1.25rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--border);
}

.post__body h3 {
  font-family: var(--font-heading);
  font-size: 1.08rem;
  font-weight: 600;
  line-height: 1.7;
  color: var(--fg);
  margin-top: 2.25rem;
  margin-bottom: .75rem;
}

.post__body blockquote {
  margin: 2rem 0;
  padding: .5rem 0 .5rem 1.25rem;
  border-left: 2px solid var(--green);
  font-family: var(--font-heading);
  font-size: 1rem;
  line-height: 1.9;
  color: var(--muted);
}

.post__body pre {
  background: #f6f6f3;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1.25rem 1.5rem;
  overflow-x: auto;
  margin: 1.5rem 0;
  font-family: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  font-size: 0.875rem;
  line-height: 1.75;
  color: #3a3a36;
}

.post__body code {
  font-family: 'JetBrains Mono', 'Fira Code', 'Courier New', monospace;
  font-size: 0.85em;
  background: #f0f0ec;
  border: 1px solid var(--border);
  padding: 1px 5px;
  border-radius: 3px;
  color: #3a3a36;
}

.post__body pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: inherit;
}

.code-comment {
  color: #9a9a8a;
  font-style: italic;
}

.post__body ul,
.post__body ol {
  padding-left: 1.5rem;
  margin-bottom: 1.6rem;
}
.post__body li {
  margin-bottom: .4rem;
  line-height: 1.9;
}

.post__body a {
  color: var(--green-deep);
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
  transition: opacity .2s;
}
.post__body a:hover { opacity: .7; }

/* ===== POST TAGS ===== */
.post__tags {
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  margin-top: 2.5rem;
  padding-top: 2rem;
  border-top: 1px solid var(--border);
}

/* ===== POST NAV ===== */
.post-nav {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-top: 2.5rem;
}
.post-nav__item {
  display: flex;
  flex-direction: column;
  gap: .5rem;
  padding: 1.25rem 1.5rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--card-bg);
  transition: box-shadow .2s, border-color .2s;
}
.post-nav__item:hover {
  box-shadow: 0 2px 10px rgba(0,0,0,.05);
  border-color: var(--green);
}
.post-nav__item--next {
  text-align: right;
}
.post-nav__label {
  font-size: 0.875rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
}
.post-nav__title {
  font-family: var(--font-heading);
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--fg);
}
.post-nav__item:hover .post-nav__title {
  color: var(--green-deep);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 720px) {
  .post-layout {
    grid-template-columns: 1fr;
  }
  .post__title {
    font-size: 1.25rem;
  }
  .breadcrumb__item[aria-current="page"] {
    max-width: 20ch;
  }
  .toc {
    padding: 1rem 1.25rem;
  }
  .post__body pre {
    font-size: 0.875rem;
    padding: 1rem;
  }
  .code-copy { opacity: 1; }
  .post-nav {
    grid-template-columns: 1fr;
  }
  .post-nav__item--next {
    text-align: left;
  }
}