/* ── post page layout ── */
.post-layout {
  margin-top: 72px;
  max-width: 1100px;
  margin-left: auto;
  margin-right: auto;
  display: grid;
  grid-template-columns: 1fr 240px;
  gap: 0;
  min-height: calc(100svh - 72px);
  align-items: start;
}

/* ── article ── */
.post-content {
  padding: 3.5rem 3rem 5rem 2rem;
  border-right: 1px solid color-mix(in srgb, var(--fg) 8%, transparent);
  min-width: 0;
}

.post-header {
  margin-bottom: 2.5rem;
  padding-bottom: 1.5rem;
  border-bottom: 1px solid color-mix(in srgb, var(--fg) 8%, transparent);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.post-header-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.post-title {
  font-family: var(--font-serif);
  font-size: clamp(1.9rem, 4vw, 3rem);
  font-weight: 700;
  line-height: 1.1;
  text-wrap: balance;
}

.post-meta-row {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.post-date {
  font-family: var(--font-nav);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--fg);
  filter: opacity(0.35);
}

.post-read-time {
  font-family: var(--font-nav);
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: #00a846;
  filter: opacity(0.8);
}

/* ── body content ── */
.post-body {
  font-family: var(--font-serif);
  font-size: clamp(0.95rem, 1.5vw, 1.05rem);
  line-height: 1.85;
  color: var(--fg);
}

.post-body h2 {
  font-size: clamp(1.2rem, 2.5vw, 1.6rem);
  font-weight: 700;
  margin: 2.5rem 0 0.8rem;
  line-height: 1.2;
}

.post-body h3 {
  font-size: 1.1rem;
  font-weight: 700;
  margin: 2rem 0 0.6rem;
}

.post-body p {
  margin-bottom: 1.1rem;
}

.post-body p:empty {
  display: none;
}

.post-body strong { font-weight: 700; }
.post-body em     { font-style: italic; }

.post-body img {
  width: 100%;
  max-width: 100%;
  min-width: 100%;
  height: auto;
  border-radius: 3px;
  margin: 1.5rem 0 0.5rem;
  display: block;
  object-fit: cover;
}

.post-body .img-caption {
  font-family: Georgia, 'Times New Roman', serif;
  font-size: 0.78rem;
  font-style: italic;
  filter: opacity(0.45);
  margin-bottom: 1.5rem;
  display: block;
}

.post-body pre {
  background-color: color-mix(in srgb, var(--fg) 5%, transparent);
  border: 1px solid color-mix(in srgb, var(--fg) 10%, transparent);
  border-left: 3px solid #00a846;
  border-radius: 3px;
  padding: 1.2rem 1.4rem;
  margin: 1.5rem 0;
  overflow-x: auto;
  font-size: 0.85rem;
  line-height: 1.6;
}

.post-body code {
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.88em;
}

.post-body p code {
  background-color: color-mix(in srgb, var(--fg) 8%, transparent);
  padding: 0.1em 0.4em;
  border-radius: 2px;
}

/* ── python runner ── */
.py-block {
  margin: 1.5rem 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

/* ── spoiler toggle ── */
.py-spoiler-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  font-family: var(--font-nav);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--fg);
  background: color-mix(in srgb, var(--fg) 4%, transparent);
  border: 1.5px solid color-mix(in srgb, var(--fg) 12%, transparent);
  border-radius: 3px 3px 0 0;
  padding: 0.7em 1.1em;
  cursor: pointer;
  margin-bottom: 0;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
  box-sizing: border-box;
}

.py-spoiler-toggle:hover {
  border-color: #00a846;
  color: #00a846;
  background: color-mix(in srgb, #00a846 6%, transparent);
}

.py-spoiler-toggle.is-open {
  border-color: #00a846;
  color: #00a846;
  background: color-mix(in srgb, #00a846 6%, transparent);
  border-bottom-color: transparent;
}

.py-spoiler-left {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.py-lang-badge {
  font-size: 0.58rem;
  background: #00a846;
  color: #fff;
  padding: 0.15em 0.5em;
  border-radius: 2px;
  letter-spacing: 0.06em;
}

.py-toggle-icon {
  font-style: normal;
  display: inline-block;
  transition: transform 0.2s ease;
  opacity: 0.5;
}

.py-spoiler-toggle.is-open .py-toggle-icon {
  transform: rotate(90deg);
  opacity: 1;
}

.py-code-wrap {
  overflow: hidden;
  max-height: 0;
  opacity: 0;
  transition: max-height 0.35s ease, opacity 0.25s ease;
  border: 1.5px solid #00a846;
  border-top: none;
  border-radius: 0 0 3px 3px;
}

.py-code-wrap.is-open {
  max-height: 800px;
  opacity: 1;
}

.py-code-wrap pre {
  border-radius: 0 !important;
  border: none !important;
  margin: 0 !important;
}

.py-block pre {
  margin: 0;
}

.py-run-btn {
  align-self: flex-end;
  margin-top: 0.6rem;
  font-family: var(--font-nav);
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.35em 1em;
  background-color: #00a846;
  color: #ffffff;
  border: none;
  border-radius: 2px;
  cursor: pointer;
  transition: background-color 0.15s ease, opacity 0.15s ease;
}

.py-run-btn:hover  { background-color: #008f3b; }
.py-run-btn:disabled { opacity: 0.5; cursor: wait; }

.py-output {
  margin-top: 0.75rem;
  border-radius: 3px;
  border: 1px solid color-mix(in srgb, var(--fg) 10%, transparent);
  overflow: hidden;
}

.py-output-label {
  display: block;
  font-family: var(--font-nav);
  font-size: 0.6rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--fg);
  filter: opacity(0.4);
  padding: 0.45rem 1rem;
  border-bottom: 1px solid color-mix(in srgb, var(--fg) 8%, transparent);
  background-color: color-mix(in srgb, var(--fg) 3%, transparent);
}

.py-output-content {
  font-family: 'Courier New', Courier, monospace;
  font-size: 0.83rem;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
  padding: 0.9rem 1.2rem;
  color: var(--fg);
}

.py-output--running .py-output-content { filter: opacity(0.45); }
.py-output--error   .py-output-content { color: #cc3333; }

.post-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-family: var(--font-serif);
  font-size: 0.92rem;
}

.post-body th {
  font-family: var(--font-nav);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--fg);
  opacity: 0.5;
  text-align: left;
  padding: 0.5rem 1rem 0.5rem 0;
  border-bottom: 2px solid color-mix(in srgb, var(--fg) 12%, transparent);
}

.post-body td {
  padding: 0.45rem 1rem 0.45rem 0;
  border-bottom: 1px solid color-mix(in srgb, var(--fg) 6%, transparent);
  color: var(--fg);
  vertical-align: top;
}

.post-body td:last-child,
.post-body th:last-child {
  padding-right: 0;
}

.post-body tr:last-child td {
  border-bottom: none;
}

.post-body hr {
  border: none;
  border-top: 1px solid color-mix(in srgb, var(--fg) 12%, transparent);
  margin: 2.5rem 0;
}

/* ── sidebar ── */
.post-sidebar {
  position: sticky;
  top: 72px;
  padding: 2rem 1.5rem;
  max-height: calc(100svh - 72px);
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

.sidebar-heading {
  font-family: var(--font-nav);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--fg);
  filter: opacity(0.4);
}

/* ── tag filter ── */
.sidebar-filter {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.filter-chip {
  font-family: var(--font-nav);
  font-size: 0.6rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 0.25em 0.65em;
  border-radius: 2px;
  border: 1.5px solid color-mix(in srgb, var(--fg) 18%, transparent);
  color: var(--fg);
  filter: opacity(0.5);
  cursor: pointer;
  transition: all 0.15s ease;
  user-select: none;
}

.filter-chip:hover {
  filter: opacity(1);
  border-color: #00a846;
  color: #00a846;
}

.filter-chip.is-active {
  background-color: #00a846;
  border-color: #00a846;
  color: #ffffff;
  filter: opacity(1);
}

/* ── sidebar article list ── */
.sidebar-list {
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.sidebar-item {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  padding: 0.7rem 0.8rem;
  border-radius: 3px;
  text-decoration: none;
  color: var(--fg);
  transition: background-color 0.15s ease;
  border: 1px solid transparent;
}

.sidebar-item:hover {
  background-color: color-mix(in srgb, var(--fg) 4%, transparent);
  border-color: color-mix(in srgb, var(--fg) 8%, transparent);
}

.sidebar-item.is-current {
  border-color: #00a846;
  background-color: color-mix(in srgb, #00a846 6%, transparent);
}

.sidebar-item-title {
  font-family: var(--font-serif);
  font-size: 0.82rem;
  font-weight: 700;
  line-height: 1.3;
}

.sidebar-item-date {
  font-family: var(--font-nav);
  font-size: 0.6rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  filter: opacity(0.35);
}

.sidebar-item[hidden] { display: none; }

/* ── lists ── */
.post-body ul {
  margin: 1rem 0;
  padding: 0;
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.post-body li {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  font-family: var(--font-serif);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--fg);
}

.post-body li::before {
  content: '';
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: #00a846;
  flex-shrink: 0;
  margin-top: 0.45em;
}

/* ── tables ── */
.post-body table {
  width: 100%;
  border-collapse: collapse;
  margin: 1.5rem 0;
  font-family: var(--font-serif);
  font-size: 0.92rem;
}

.post-body th {
  font-family: var(--font-nav);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--fg);
  opacity: 0.5;
  text-align: left;
  padding: 0.5rem 1rem 0.5rem 0;
  border-bottom: 2px solid color-mix(in srgb, var(--fg) 12%, transparent);
}

.post-body td {
  padding: 0.45rem 1rem 0.45rem 0;
  border-bottom: 1px solid color-mix(in srgb, var(--fg) 6%, transparent);
  color: var(--fg);
  vertical-align: top;
}

.post-body td:last-child,
.post-body th:last-child {
  padding-right: 0;
}

.post-body tr:last-child td {
  border-bottom: none;
}

/* ── example box ── */
.example-box {
  margin: 0.35rem 0;
  padding: 0.4rem 1rem;
  border-left: 3px solid #00a846;
  background-color: color-mix(in srgb, #00a846 5%, var(--bg));
  border-radius: 0 4px 4px 0;
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.example-rule {
  font-family: var(--font-nav);
  font-size: 0.72rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--fg);
  opacity: 0.6;
  padding-bottom: 0.2rem;
}

.example-calc {
  font-family: var(--font-serif);
  font-size: 1rem;
  color: var(--fg);
  padding-bottom: 0.2rem;
}

.example-calc .wrong {
  color: #e03535;
  text-decoration: line-through;
  opacity: 0.7;
}

.example-calc .right {
  color: #00a846;
  font-weight: 700;
}

.example-note {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  color: var(--fg);
  opacity: 0.75;
  font-style: italic;
  padding-bottom: 0.15rem;
}

/* ── method rating ── */
.method-rating {
  display: flex;
  flex-direction: column;
  gap: 0;
  margin: 1rem 0 0.3rem;
  padding: 0.25rem 1.4rem 1.1rem;
  border-left: 3px solid #00a846;
  background-color: color-mix(in srgb, #00a846 5%, var(--bg));
  border-radius: 0 4px 4px 0;
}

.rating-row {
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.rating-label {
  font-family: var(--font-nav);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--fg);
  opacity: 0.75;
  width: 9.5rem;
  flex-shrink: 0;
}

.stars {
  display: inline-flex;
  line-height: 1;
}

.stars-filled {
  color: #00a846;
  letter-spacing: 0.04em;
  font-size: 1.1rem;
}

.stars-empty {
  color: #00a846;
  opacity: 0.28;
  letter-spacing: 0.04em;
  font-size: 1.1rem;
}

/* ── sigfig true/false widget (pure CSS, no JS) ── */
@keyframes sfp-ok  { 0% { background: color-mix(in srgb,#00a846 18%,transparent); } 100% { background: transparent; } }
@keyframes sfp-err { 0%,100%{transform:translateX(0)} 25%{transform:translateX(-5px)} 75%{transform:translateX(5px)} }
@keyframes sfp-pop { from{transform:scale(0);opacity:0} 65%{transform:scale(1.25)} to{transform:scale(1);opacity:1} }

.sfp-list { display:flex; flex-direction:column; gap:0.32rem; margin:1rem 0; }

.sfp-r { display:none; }

.sfp-inner {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.6rem;
  padding: 0.38rem 0.8rem;
  border: 1px solid color-mix(in srgb, var(--fg) 9%, transparent);
  border-radius: 5px;
  transition: border-color 0.2s;
}

.sfp-stmt { font-family:var(--font-serif); font-size:0.93rem; color:var(--fg); flex:1; min-width:0; }
.sfp-ctx  { font-size:0.74rem; opacity:0.4; }

.sfp-acts { display:flex; align-items:center; gap:0.3rem; flex-shrink:0; }

.sfp-tl, .sfp-fl {
  font-family: var(--font-nav);
  font-size: 0.67rem;
  font-weight: 600;
  letter-spacing: 0.05em;
  padding: 0.17rem 0.62rem;
  border: 1.5px solid color-mix(in srgb, var(--fg) 20%, transparent);
  border-radius: 4px;
  cursor: pointer;
  user-select: none;
  color: var(--fg);
  transition: border-color 0.12s, color 0.12s;
}
.sfp-tl:hover { border-color:#00a846; color:#00a846; }
.sfp-fl:hover { border-color:#e03535; color:#e03535; }

.sfp-ok, .sfp-ko { display:none; font-size:0.9rem; }
.sfp-ok { color:#00a846; }
.sfp-ko { color:#e03535; }

.sfp-why {
  display: none;
  flex-basis: 100%;
  font-family: var(--font-serif);
  font-size: 0.78rem;
  font-style: italic;
  opacity: 0.58;
  padding-top: 0.02rem;
}

/* ── sfp-ct: correct = True ── */
.sfp-ct .sfp-tr:checked ~ .sfp-inner                  { animation:sfp-ok  0.55s ease-out; border-color:#00a846; }
.sfp-ct .sfp-tr:checked ~ .sfp-inner .sfp-tl          { border-color:#00a846; color:#00a846; }
.sfp-ct .sfp-tr:checked ~ .sfp-inner .sfp-ok          { display:inline; animation:sfp-pop 0.28s ease-out; }
.sfp-ct .sfp-tr:checked ~ .sfp-inner .sfp-why         { display:block; }

.sfp-ct .sfp-fr:checked ~ .sfp-inner                  { animation:sfp-err 0.4s ease; border-color:#e03535; }
.sfp-ct .sfp-fr:checked ~ .sfp-inner .sfp-fl          { border-color:#e03535; color:#e03535; }
.sfp-ct .sfp-fr:checked ~ .sfp-inner .sfp-ko          { display:inline; animation:sfp-pop 0.28s ease-out; }
.sfp-ct .sfp-fr:checked ~ .sfp-inner .sfp-why         { display:block; }

/* ── sfp-cf: correct = False ── */
.sfp-cf .sfp-fr:checked ~ .sfp-inner                  { animation:sfp-ok  0.55s ease-out; border-color:#00a846; }
.sfp-cf .sfp-fr:checked ~ .sfp-inner .sfp-fl          { border-color:#00a846; color:#00a846; }
.sfp-cf .sfp-fr:checked ~ .sfp-inner .sfp-ok          { display:inline; animation:sfp-pop 0.28s ease-out; }
.sfp-cf .sfp-fr:checked ~ .sfp-inner .sfp-why         { display:block; }

.sfp-cf .sfp-tr:checked ~ .sfp-inner                  { animation:sfp-err 0.4s ease; border-color:#e03535; }
.sfp-cf .sfp-tr:checked ~ .sfp-inner .sfp-tl          { border-color:#e03535; color:#e03535; }
.sfp-cf .sfp-tr:checked ~ .sfp-inner .sfp-ko          { display:inline; animation:sfp-pop 0.28s ease-out; }
.sfp-cf .sfp-tr:checked ~ .sfp-inner .sfp-why         { display:block; }

/* ── post feedback ── */
.post-feedback {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid color-mix(in srgb, var(--fg) 10%, transparent);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.feedback-reactions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.feedback-like,
.feedback-dislike {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-nav);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  padding: 0.45em 0.9em;
  border-radius: 3px;
  border: 1.5px solid;
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.feedback-like {
  color: color-mix(in srgb, #00a846 70%, var(--fg));
  background-color: color-mix(in srgb, #00a846 8%, transparent);
  border-color: color-mix(in srgb, #00a846 25%, transparent);
}

.feedback-like:hover {
  background-color: color-mix(in srgb, #00a846 15%, transparent);
  border-color: #00a846;
}

.feedback-like.is-active {
  background-color: #00a846;
  border-color: #00a846;
  color: #ffffff;
}

.feedback-like-label {
  text-transform: uppercase;
}

.feedback-dislike {
  color: color-mix(in srgb, #cc3333 70%, var(--fg));
  background-color: color-mix(in srgb, #cc3333 8%, transparent);
  border-color: color-mix(in srgb, #cc3333 25%, transparent);
}

.feedback-dislike:hover {
  background-color: color-mix(in srgb, #cc3333 15%, transparent);
  border-color: #cc3333;
}

.feedback-dislike.is-active {
  background-color: #cc3333;
  border-color: #cc3333;
  color: #ffffff;
}

.feedback-comment-box {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.feedback-prompt {
  font-family: var(--font-serif);
  font-size: 0.9rem;
  color: var(--fg);
  margin: 0;
}

.feedback-prompt-sub {
  font-style: italic;
  font-size: 0.82rem;
  opacity: 0.5;
}

.feedback-textarea {
  font-family: var(--font-serif);
  font-size: 0.88rem;
  line-height: 1.6;
  color: var(--fg);
  background-color: color-mix(in srgb, var(--fg) 3%, transparent);
  border: 1.5px solid color-mix(in srgb, var(--fg) 12%, transparent);
  border-radius: 3px;
  padding: 0.7rem 0.9rem;
  resize: vertical;
  width: 100%;
  box-sizing: border-box;
  transition: border-color 0.15s ease;
}

.feedback-textarea:focus {
  outline: none;
  border-color: #00a846;
}

.feedback-submit-row {
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

.feedback-submit {
  font-family: var(--font-nav);
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  padding: 0.4em 1.1em;
  background-color: color-mix(in srgb, var(--fg) 7%, transparent);
  color: var(--fg);
  border: 1.5px solid color-mix(in srgb, var(--fg) 15%, transparent);
  border-radius: 2px;
  cursor: pointer;
  transition: background-color 0.15s ease, border-color 0.15s ease;
}

.feedback-submit:hover {
  background-color: color-mix(in srgb, var(--fg) 12%, transparent);
  border-color: color-mix(in srgb, var(--fg) 25%, transparent);
}

.feedback-submit:disabled { opacity: 0.4; cursor: wait; }

.feedback-thanks {
  font-family: var(--font-serif);
  font-size: 0.82rem;
  font-style: italic;
  color: #00a846;
  opacity: 0.8;
}

/* ── responsive ── */
@media (max-width: 860px) {
  .post-layout {
    grid-template-columns: 1fr;
    margin-top: 72px;
  }

  .post-content {
    padding: 1.75rem 1rem 3rem;
    border-right: none;
  }

  .post-sidebar {
    position: static;
    max-height: none;
    border-top: 1px solid color-mix(in srgb, var(--fg) 8%, transparent);
    padding: 1.5rem 1rem 2rem;
  }

  .post-body {
    font-size: 0.95rem;
  }
}