/* =====================================================================
   article.css — Theme "Bí Kíp" cho trang bài viết + editor WYSIWYG
   Tách từ mẫu gốc. Dùng chung cho: trang public (posts/show) và
   khung soạn thảo TinyMCE (content_css) để "viết sao thấy vậy".
   ===================================================================== */
:root{
  --paper:#E9ECEF;
  --surface:#FBFCFD;
  --surface-2:#F1F3F5;
  --ink:#12161C;
  --ink-2:#454F5B;
  --ink-3:#79838F;
  --line:#D8DCE1;
  --line-soft:#E4E7EB;
  --code-bg:#12161D;
  --code-fg:#DCE1E8;
  --code-comment:#6E7A8C;
  --code-kw:#7CA9F2;
  --code-str:#8FD48A;
  --code-num:#E0A66A;
  --code-fn:#E6C46B;
  --sans:'Be Vietnam Pro', system-ui, 'Segoe UI', Roboto, sans-serif;
  --mono:'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
  --brand:#2563EB; /* ⬅ MÀU CHỦ ĐẠO (xanh biển) — đổi 1 dòng này là đổi cả site */
  --acc:var(--brand);
  --sheet:#ffffff; /* nền "tờ giấy" — đổi theo theme */
}

/* ---------- DARK MODE ---------- */
:root[data-theme="dark"]{
  --paper:#0d1117;
  --sheet:#1a212b;
  --surface:#161b22;
  --surface-2:#232b37;
  --ink:#e9eef4;
  --ink-2:#aeb8c4;
  --ink-3:#7d8896;
  --line:#2c3542;
  --line-soft:#232b35;
  --acc:color-mix(in srgb, var(--brand) 74%, #ffffff);
}

*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;
  background:var(--paper);
  color:var(--ink);
  font-family:var(--sans);
  font-size:16px;
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
.wrap{max-width:940px;margin:0 auto;padding:0 20px 96px;}

/* ---------- HERO ---------- */
.hero{padding:64px 0 40px;border-bottom:2px dashed var(--paper);}
.kicker{
  font-family:var(--mono);
  font-size:12.5px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--ink-3);
  margin:0 0 18px;
}
.hero h1{
  font-size:clamp(34px,7vw,60px);
  line-height:1.02;
  font-weight:800;
  letter-spacing:-.02em;
  margin:0 0 18px;
}
.hero h1 .dim{color:var(--ink-3);font-weight:700;}
.hero p.lead{
  font-size:clamp(16px,2.2vw,19px);
  color:var(--ink-2);
  margin:0;
}
.hero .meta{
  font-family:var(--mono);
  font-size:12px;
  color:var(--ink-3);
  margin-top:26px;
  display:flex;gap:8px;flex-wrap:wrap;align-items:center;
}
.hero .meta span{background:var(--surface-2);padding:3px 9px;border-radius:50px;}

/* ---------- NAV CHIPS ---------- */
.nav{display:flex;flex-wrap:wrap;gap:8px;margin:32px 0 8px;}
.nav a{
  font-family:var(--mono);
  font-size:12.5px;
  text-decoration:none;
  color:var(--ink);
  background:var(--surface);
  border:1px solid var(--line);
  border-left:3px solid var(--c, var(--acc));
  padding:7px 12px;
  border-radius:3px;
  transition:transform .12s ease, background .12s ease;
}
.nav a:hover{transform:translateY(-2px);background:var(--surface-2);}
.nav a b{color:var(--c, var(--acc));}

/* ---------- SECTION HEADS ---------- */
.sec-head{margin:64px 0 22px;}
.sec-head .eyebrow{
  font-family:var(--mono);
  font-size:12px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--ink-3);margin:0 0 8px;
}
.sec-head h2{
  font-size:clamp(24px,4vw,32px);font-weight:800;letter-spacing:-.015em;margin:0;
}
.sec-head p{color:var(--ink-2);margin:10px 0 0;max-width:660px;}

/* ---------- DECISION TABLE ---------- */
.table-scroll{overflow-x:auto;border:1px solid var(--line);border-radius:8px;background:var(--surface);}
table.decide{width:100%;border-collapse:collapse;min-width:560px;}
table.decide th,table.decide td{text-align:left;padding:14px 16px;vertical-align:top;border-bottom:1px solid var(--line-soft);}
table.decide thead th{
  font-family:var(--mono);font-size:11.5px;letter-spacing:.14em;text-transform:uppercase;
  color:var(--ink-3);background:var(--surface-2);font-weight:500;
}
table.decide tbody tr:last-child td{border-bottom:none;}
table.decide td.sig{color:var(--ink-2);}
table.decide td.sig b{color:var(--ink);font-weight:600;}
.pill{
  display:inline-flex;align-items:center;gap:8px;
  font-family:var(--mono);font-size:12.5px;font-weight:500;white-space:nowrap;
  color:var(--ink);
}
.pill::before{content:"";width:10px;height:10px;border-radius:50%;background:var(--c, var(--acc));flex:0 0 auto;}

/* ---------- PATTERN CARD ---------- */
.pattern{
  background:var(--surface);
  border:1px solid var(--line);
  border-top:4px solid var(--acc);
  border-radius:10px;
  padding:30px 30px 34px;
  margin-top:26px;
  box-shadow:0 1px 0 rgba(18,22,28,.03), 0 10px 30px -24px rgba(18,22,28,.4);
}
.p-top{display:flex;align-items:baseline;gap:14px;flex-wrap:wrap;margin-bottom:4px;}
.p-num{font-family:var(--mono);font-size:13px;font-weight:700;color:var(--acc);letter-spacing:.05em;}
.p-en{font-size:clamp(22px,3.4vw,28px);font-weight:800;letter-spacing:-.01em;margin:0;}
.p-vi{font-family:var(--mono);font-size:13px;color:var(--ink-3);}
.p-badge{
  margin-left:auto;font-family:var(--mono);font-size:11.5px;
  background:var(--surface-2);border:1px solid var(--line);
  padding:4px 10px;border-radius:20px;color:var(--ink-2);white-space:nowrap;
}
.idea{
  font-size:17px;color:var(--ink);margin:14px 0 4px;
  padding-left:14px;border-left:3px solid var(--acc);
}

/* ---------- VIZ (array cell figures) ---------- */
.viz{
  background:var(--surface-2);
  border:1px solid var(--line-soft);
  border-radius:8px;
  padding:22px 18px 16px;
  margin:20px 0;
  overflow-x:auto;
}
.cells{display:inline-flex;gap:6px;font-family:var(--mono);}
.cells.stack{flex-direction:column;gap:4px;align-items:flex-start;}
.row{display:inline-flex;gap:6px;}
.cell{
  width:42px;height:42px;flex:0 0 auto;
  display:flex;align-items:center;justify-content:center;
  background:var(--surface);border:1px solid var(--line);border-radius:5px;
  font-size:14px;font-weight:500;color:var(--ink);position:relative;
}
.cell.dim{color:var(--ink-3);background:transparent;border-style:dashed;}
.cell.win{background:color-mix(in srgb,var(--acc) 16%,var(--surface));border-color:var(--acc);}
.cell.edge{box-shadow:inset 0 0 0 2px var(--acc);}
.cell.hit{background:var(--acc);border-color:var(--acc);color:#fff;font-weight:700;}
.mark{
  position:absolute;top:-20px;left:50%;transform:translateX(-50%);
  font-size:11px;font-weight:700;color:var(--acc);white-space:nowrap;font-family:var(--mono);
}
.mark.bot{top:auto;bottom:-22px;}
.viz-cap{
  font-family:var(--mono);font-size:12px;color:var(--ink-2);margin-top:18px;line-height:1.5;
}
.viz-cap .k{color:var(--acc);font-weight:700;}

/* interval bars viz */
.bars{display:flex;flex-direction:column;gap:8px;font-family:var(--mono);min-width:340px;}
.axis{display:flex;gap:0;font-size:11px;color:var(--ink-3);}
.axis span{width:34px;text-align:center;}
.bar{height:20px;border-radius:4px;background:color-mix(in srgb,var(--acc) 28%,var(--surface));border:1px solid var(--acc);}
.bar.solid{background:var(--acc);border-color:var(--acc);}
.bar-lane{position:relative;height:20px;}
.bar-lane .bar{position:absolute;top:0;}

/* ---------- SUBHEADS INSIDE CARD ---------- */
.block-label{
  font-family:var(--mono);font-size:11.5px;letter-spacing:.16em;text-transform:uppercase;
  color:var(--ink-3);margin:24px 0 10px;display:flex;align-items:center;gap:8px;
}
.block-label::before{content:"";width:14px;height:2px;background:var(--acc);}
ul.signals{margin:0;padding:0;list-style:none;}
ul.signals li{
  position:relative;padding:5px 0 5px 22px;color:var(--ink-2);border-bottom:1px dashed var(--line-soft);
}
ul.signals li:last-child{border-bottom:none;}
ul.signals li::before{content:"▸";position:absolute;left:2px;color:var(--acc);font-size:12px;top:6px;}
ul.signals li b{color:var(--ink);font-weight:600;}

/* ---------- MEMORY HOOK ---------- */
.hook{
  background:color-mix(in srgb,var(--acc) 8%,var(--surface));
  border:1px solid color-mix(in srgb,var(--acc) 35%,var(--line));
  border-radius:8px;padding:14px 16px 14px 46px;position:relative;margin:8px 0 4px;
}
.hook::before{
  content:"🧠";position:absolute;left:14px;top:12px;font-size:18px;
}
.hook .h-lab{font-family:var(--mono);font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--acc);font-weight:700;display:block;margin-bottom:3px;}
.hook p{margin:0;color:var(--ink);font-weight:500;}
/* Biến thể callout: đổi icon + màu theo loại (tip / key / link / warn) */
.hook.tip::before{content:"💡";}
.hook.key::before{content:"🔑";}
.hook.link::before{content:"🔗";}
.hook.warn::before{content:"⚠️";}
.hook.warn{background:color-mix(in srgb,#e0a608 12%,var(--surface));border-color:color-mix(in srgb,#e0a608 42%,var(--line));}
.hook.warn .h-lab{color:#b7791f;}
:root[data-theme="dark"] .hook.warn .h-lab{color:#e3b341;}

/* Dải phân cách "PHẦN X" giữa các nhóm lớn (KHÔNG nằm trong mục lục) */
.part-divider{font-family:var(--mono);font-size:12px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--acc);font-weight:700;border-top:2px solid color-mix(in srgb,var(--acc) 55%,var(--line));
  padding-top:15px;margin:54px 0 6px;}

/* ---------- CODE ---------- */
pre{
  background:var(--code-bg);color:var(--code-fg);
  border-radius:8px;padding:18px 18px;margin:0px 30px;
  overflow-x:auto;font-family:var(--mono);font-size:13px;line-height:1.6;
  border:1px solid #000;
}
pre code{font-family:var(--mono);background:none;padding:0;border:0;color:inherit;}

/* code.language-python {
  background-color: None !important;
  text-shadow: None !important;
  color: #fff !important;
} */

/* Khi editor được focus */
.tox.tox-tinymce.tox-edit-focus {
  border: 2px solid #0077B5 !important; /* xanh LinkedIn */
  box-shadow: 0 0 5px rgba(0, 119, 181, 0.5) !important;
}

/* Khi hover vào editor */
.tox.tox-tinymce:hover {
  border: 2px solid #00FF00 !important; /* xanh lá */
}


/* Khối code có thanh tiêu đề ngôn ngữ + nút Copy (thêm bằng JS ở trang bài viết) */
.code-block{margin:12px 0 4px;border-radius:8px;overflow:hidden;border:1px solid #000;}
.code-bar{display:flex;align-items:center;justify-content:space-between;background:#0d1117;
  padding:7px 10px 7px 14px;border-bottom:1px solid rgba(255,255,255,.07);}
.code-lang{font-family:var(--mono);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:#8b96a8;}
.code-copy{display:inline-flex;align-items:center;gap:6px;font-family:var(--mono);font-size:11.5px;color:#c2cbd8;
  background:rgba(255,255,255,.06);border:1px solid rgba(255,255,255,.12);border-radius:6px;padding:4px 9px;cursor:pointer;transition:.12s;line-height:1;}
.code-copy:hover{color:#fff;background:rgba(255,255,255,.13);border-color:rgba(255,255,255,.22);}
.code-copy.ok{color:#7ee0b4;border-color:rgba(126,224,180,.4);}
.code-copy svg{width:13px;height:13px;}
.code-body{display:flex;align-items:stretch;background:var(--code-bg);}
.code-gutter{flex:0 0 auto;text-align:right;user-select:none;white-space:pre;
  font-family:var(--mono);font-size:13px;line-height:1.6;color:#5b6675;
  padding:18px 12px 18px 16px;border-right:1px solid rgba(255,255,255,.07);background:rgba(0,0,0,.18);}
.code-block pre{margin:0;border:none;border-radius:0;flex:1 1 auto;min-width:0;}
/* tab chuyển ngôn ngữ */
.code-tabbar{display:flex;gap:3px;flex-wrap:wrap;}
.code-tab{font-family:var(--mono);font-size:11px;letter-spacing:.05em;text-transform:uppercase;
  color:#7d8aa0;background:transparent;border:none;border-radius:6px;padding:4px 11px;cursor:pointer;transition:.12s;line-height:1;}
.code-tab:hover{color:#c9d2df;background:rgba(255,255,255,.06);}
.code-tab.on{color:#fff;background:rgba(255,255,255,.13);}
.code-panels{background:var(--code-bg);}
/* Gợi ý trong EDITOR: khối .code-tabs sẽ được gộp thành tab khi xuất bản */
.code-tabs{position:relative;border:1px dashed color-mix(in srgb,var(--acc) 50%,var(--line));border-radius:12px;padding:32px 12px 10px;margin:16px 0;}
.code-tabs::before{content:"⇥ Khối code đa ngôn ngữ — mỗi khối = 1 tab khi xuất bản";position:absolute;top:9px;left:14px;
  font-family:var(--mono);font-size:10.5px;letter-spacing:.03em;color:var(--acc);}
.hljs-comment{color:var(--code-comment);font-style:italic;}
.hljs-keyword,.hljs-built_in.hljs-keyword{color:var(--code-kw);}
.hljs-string{color:var(--code-str);}
.hljs-number{color:var(--code-num);}
.hljs-title,.hljs-title.function_,.hljs-built_in{color:var(--code-fn);}
.hljs-params{color:var(--code-fg);}

/* inline code (mọi nơi trừ trong khối <pre>): chữ tối trên nền chip sáng -> luôn tương phản nền */
:not(pre) > code{
  font-family:var(--mono);font-size:.9em;background:var(--surface-2);color:var(--ink);
  padding:1px 6px;border-radius:5px;border:1px solid var(--line-soft);
}

/* worked example */
.example{border-top:1px solid var(--line-soft);margin-top:24px;padding-top:20px;}
.example .prob{font-family:var(--mono);font-size:12.5px;color:var(--acc);font-weight:700;margin:0 0 6px;}
.example .prob .lc{color:var(--ink-3);font-weight:500;}
.example p{margin:8px 0;color:var(--ink-2);}
.example p b{color:var(--ink);}
.trace{
  font-family:var(--mono);font-size:12.5px;background:var(--surface-2);
  border:1px solid var(--line-soft);border-radius:6px;padding:12px 14px;color:var(--ink-2);
  margin:10px 0;overflow-x:auto;white-space:pre;
}
.variants{font-size:14px;color:var(--ink-2);margin-top:6px;}
.variants b{color:var(--ink);}

/* ---------- CALLOUT: confused ---------- */
.confuse{
  background:var(--surface);border:1px solid var(--line);border-radius:10px;
  padding:26px 28px;margin-top:26px;
}
.confuse h3{font-size:18px;margin:0 0 6px;font-weight:800;}
.confuse .pair{margin:16px 0;padding-left:16px;border-left:3px solid var(--line);}
.confuse .pair .vs{font-family:var(--mono);font-size:13px;font-weight:700;color:var(--ink);}
.confuse .pair p{margin:6px 0 0;color:var(--ink-2);font-size:15px;}

/* ---------- 4 STEPS ---------- */
.steps{counter-reset:step;margin-top:22px;display:grid;gap:12px;}
.step{
  display:grid;grid-template-columns:auto 1fr;gap:16px;align-items:start;
  background:var(--surface);border:1px solid var(--line);border-radius:10px;padding:18px 20px;
}
.step::before{
  counter-increment:step;content:counter(step);
  font-family:var(--mono);font-weight:700;font-size:15px;
  width:34px;height:34px;border-radius:8px;background:var(--ink);color:var(--paper);
  display:flex;align-items:center;justify-content:center;
}
.step h4{margin:2px 0 4px;font-size:16px;font-weight:700;}
.step p{margin:0;color:var(--ink-2);font-size:15px;}
.step p code{font-family:var(--mono);font-size:13px;background:var(--surface-2);padding:1px 6px;border-radius:4px;border:1px solid var(--line-soft);color:var(--ink);}

/* ---------- Chữ thường trong bài (paragraph, heading, list, quote, ảnh) ----------
   Dùng :where() để giữ specificity = 0 cho phần container, nhờ đó MỌI class
   thành phần (.sec-head, .p-en, .signals, .nav...) luôn thắng và không bị đè. */
:where(.article-body) h2{font-size:clamp(22px,3.6vw,30px);font-weight:800;letter-spacing:-.015em;margin:52px 0 14px;}
:where(.article-body) h3{font-size:clamp(19px,2.8vw,23px);font-weight:700;margin:36px 0 10px;}
:where(.article-body) h4{font-size:17px;font-weight:700;margin:26px 0 8px;}
:where(.article-body) p{margin:14px 0;}
:where(.article-body) ul,
:where(.article-body) ol{margin:14px 0;padding-left:22px;}
:where(.article-body) li{margin:6px 0;}
:where(.article-body) a{color:var(--acc);text-decoration:underline;text-underline-offset:2px;}
:where(.article-body) img{max-width:100%;height:auto;border-radius:8px;border:1px solid var(--line);margin:18px 0;}
:where(.article-body) blockquote{
  margin:18px 0;padding:6px 0 6px 18px;border-left:3px solid var(--acc);
  color:var(--ink-2);font-size:17px;
}
:where(.article-body) hr{border:none;border-top:1px solid var(--line);margin:36px 0;}

/* ---------- ARTICLE SHELL: bài viết trên "tờ giấy" trắng liền mạch + mục lục ---------- */
.article-shell{
  max-width:1200px;margin:0 auto;padding:26px 24px 26px;
  display:grid;grid-template-columns:minmax(0,1fr) 250px;gap:44px;align-items:start;
}
.article-main{min-width:0;}
.article-sheet{
  background:var(--sheet);border-radius:10px;
  padding:8px 27px 27px;
  /* box-shadow:0 1px 0 rgba(18,22,28,.02), 0 30px 60px -50px rgba(18,22,28,.55); */
}
.article-sheet .hero{padding: 22px 0 30px;}
.article-back{margin:22px 2px 0;}
.article-back a{color:var(--acc);text-decoration:none;font-family:var(--mono);font-size:13px;}
.article-back a:hover{color:color-mix(in srgb,var(--acc) 80%,black);}

/* Mục lục sticky bên phải */
.article-toc{position:sticky;top:78px;align-self:start;max-height:calc(100vh - 100px);overflow:auto;}
.article-toc .toc-label{font-family:var(--mono);font-size:11px;letter-spacing:.16em;text-transform:uppercase;color:var(--ink-3);margin:0 0 12px;padding-left:15px;}
.article-toc nav{display:flex;flex-direction:column;border-left:1px solid var(--line);}
.article-toc a{
  font-size:13px;line-height:1.45;color:var(--ink-3);text-decoration:none;
  padding:6px 8px 6px 15px;margin-left:-1px;border-left:2px solid transparent;
  transition:color .12s,border-color .12s;
}
.article-toc a:hover{color:var(--ink);}
.article-toc a.active{color:var(--acc);border-left-color:var(--acc);font-weight:600;}

/* Bọc tiêu đề bằng .toc-item để nó xuất hiện trong Mục lục (opt-in) */
.toc-item{scroll-margin-top:90px;}

/* Tags nằm dưới mục lục ở sidebar phải */
.article-toc .toc-tags{margin-top:30px;}
.article-toc .toc-tags .toc-label{margin-bottom:11px;}
.article-toc .toc-tags-list{display:flex;flex-wrap:wrap;gap:7px;padding-left:15px;}

/* Bài không đủ mục -> bỏ cột mục lục, canh giữa cho đẹp */
.article-shell.no-toc{grid-template-columns:minmax(0,860px);justify-content:center;}
.article-shell.no-toc .article-toc{display:none;}

@media (max-width:960px){
  .article-shell{grid-template-columns:1fr;padding:16px 16px 26px;}
  .article-toc{display:none;}
  .article-sheet{padding:8px 20px 30px;}
}
@media (max-width:640px){
  /* Mobile: bài viết trải FULL chiều rộng màn hình (sát mép, lề trong gọn) */
  .article-shell{padding:10px 0 22px;}
  .article-sheet{border-radius:0;padding:14px 16px 26px;}
  .article-sheet .hero{padding:14px 0 22px;}
  .comments{border-radius:0;padding:22px 16px 26px;margin-top:12px;}
  .article-back{margin-left:16px;margin-right:16px;}
}

/* ---------- BÌNH LUẬN ---------- */
.comments{background:var(--sheet);border-radius:10px;padding:26px 32px 30px;margin-top:22px;
  box-shadow:0 1px 0 rgba(18,22,28,.02);}
.cm-title{font-size:20px;font-weight:800;letter-spacing:-.015em;margin:0 0 18px;display:flex;align-items:center;gap:10px;}
.cm-count{font-family:var(--mono);font-size:13px;font-weight:600;color:var(--acc);background:color-mix(in srgb,var(--acc) 14%,var(--sheet));
  border:1px solid color-mix(in srgb,var(--acc) 30%,var(--line));padding:2px 10px;border-radius:20px;}
.cm-flash{background:color-mix(in srgb,#059669 14%,var(--sheet));border:1px solid color-mix(in srgb,#059669 35%,var(--line));
  color:#0a9d67;padding:10px 14px;border-radius:9px;margin-bottom:16px;font-size:14px;}
.cm-avatar{width:40px;height:40px;flex:0 0 auto;border-radius:50%;display:flex;align-items:center;justify-content:center;
  font-weight:700;font-size:16px;color:#fff;background:var(--acc);}
.cm-form{display:flex;gap:14px;padding:16px;border-radius:10px;background:var(--surface-2);margin-bottom:24px;}
.cm-form-main{flex:1 1 auto;min-width:0;}
.cm-form textarea{width:100%;border:None;border-radius:9px;background:var(--sheet);padding:11px 13px;
  font-family:var(--sans);font-size:14.5px;line-height:1.6;resize:vertical;color:var(--ink);box-sizing:border-box;}
.cm-form textarea:focus{outline:none;border-color:var(--acc);}
.cm-err{color:#c0392b;font-size:13px;margin:6px 0 0;}
.cm-form-actions{display:flex;align-items:center;gap:12px;margin-top:10px;flex-wrap:wrap;}
.cm-as{font-size:12.5px;color:var(--ink-3);}
.cm-as b{color:var(--ink-2);}
.cm-submit{margin-left:auto;background:var(--acc);color:#fff;border:none;border-radius:9px;padding:9px 16px;
  font-weight:600;font-size:14px;cursor:pointer;font-family:var(--sans);transition:filter .12s;}
.cm-submit:hover{filter:brightness(1.08);}
.cm-login{background:var(--surface-2);border:1px dashed var(--line);border-radius:12px;padding:18px;text-align:center;
  color:var(--ink-2);font-size:14.5px;margin-bottom:24px;}
.cm-login a{color:var(--acc);font-weight:600;text-decoration:none;}
.cm-login a:hover{text-decoration:underline;}
.cm-list{display:flex;flex-direction:column;gap:20px;}
.cm-item{display:flex;gap:14px;}
.cm-body{flex:1 1 auto;min-width:0;}
.cm-meta{display:flex;align-items:center;gap:7px;font-size:14px;color:var(--ink-3);margin-bottom:4px;}
.cm-meta b{color:var(--ink);font-weight:600;font-size:14.5px;}
.cm-del{margin-left:auto;}
.cm-del button{background:none;border:none;color:var(--ink-3);font-size:12.5px;cursor:pointer;padding:2px 4px;font-family:var(--sans);}
.cm-del button:hover{color:#c0392b;}
.cm-body p{margin:0;color:var(--ink-2);font-size:15px;line-height:1.65;overflow-wrap:break-word;}
.cm-empty{color:var(--ink-3);font-size:14.5px;margin:0;}
@media (max-width:560px){
  .comments{padding:20px 18px 24px;}
  .cm-form{padding:12px;}
}

/* ---------- FOOTER ---------- */
.foot{margin-top:64px;padding-top:24px;border-top:2px solid var(--ink);font-family:var(--mono);font-size:12px;color:var(--ink-3);display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;}

a:focus-visible,.nav a:focus-visible{outline:2px solid var(--ink);outline-offset:2px;}

@media (max-width:560px){
  .wrap{padding:0 16px 72px;}
  .pattern{padding:24px 18px 28px;}
  .p-badge{margin-left:0;}
  .cell{width:38px;height:38px;}
}
@media (prefers-reduced-motion:reduce){
  *{scroll-behavior:auto;transition:none!important;}
}
@media print{
  body{background:#fff;}
  .pattern,.confuse,.step,.table-scroll{box-shadow:none;page-break-inside:avoid;}
  .nav{display:none;}
}

/* ========== SHAPE & HIỆU ỨNG (kiểu PowerPoint) ========== */
.pp-stage{position:relative;display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:16px;
  min-height:150px;margin:22px 0;padding:30px 24px;border-radius:16px;overflow:hidden;
  border:1px solid var(--line);
  background:radial-gradient(circle at 18% 15%,color-mix(in srgb,var(--acc) 12%,transparent),transparent 42%),linear-gradient(180deg,color-mix(in srgb,var(--acc) 5%,var(--surface)),var(--surface));}
.pp-stage::before{content:"";position:absolute;inset:0;pointer-events:none;opacity:.45;
  background-image:linear-gradient(color-mix(in srgb,var(--ink) 6%,transparent) 1px,transparent 1px),linear-gradient(90deg,color-mix(in srgb,var(--ink) 6%,transparent) 1px,transparent 1px);
  background-size:26px 26px;}
.pp-stage>*{position:relative;z-index:1;}

.pp-shape{display:inline-flex;align-items:center;justify-content:center;text-align:center;box-sizing:border-box;
  font-weight:700;font-size:15px;line-height:1.25;color:#fff;padding:16px 22px;min-width:92px;min-height:54px;
  background:var(--sc,#2563eb);box-shadow:0 12px 26px -14px color-mix(in srgb,var(--sc,#2563eb) 85%,transparent);}
.pp-rect{border-radius:12px;}
.pp-pill{border-radius:999px;padding:13px 28px;min-height:0;}
.pp-circle{border-radius:50%;width:104px;height:104px;min-width:0;min-height:0;padding:10px;}
.pp-diamond{clip-path:polygon(50% 0,100% 50%,50% 100%,0 50%);width:118px;height:118px;min-width:0;min-height:0;padding:0;}
.pp-badge{border-radius:9px;padding:8px 15px;min-width:0;min-height:0;font-family:var(--mono);font-size:12px;letter-spacing:.08em;text-transform:uppercase;}
.pp-note{border-radius:4px 15px 15px 15px;background:var(--sc,#fde68a);color:#5b4708;box-shadow:0 10px 22px -12px rgba(0,0,0,.45);}
.pp-arrow{background:transparent;box-shadow:none;color:var(--sc,#94a3b8);font-size:30px;font-weight:400;min-width:0;min-height:0;padding:0 4px;}
.pp-star{background:transparent;box-shadow:none;color:var(--sc,#f59e0b);font-size:42px;min-width:0;min-height:0;padding:0;}

/* Mặc định (không JS / trong trình soạn): shape hiện đầy đủ, tĩnh.
   Chỉ khi JS bật (.reveal-ready) mới ẩn -> animate lúc cuộn tới. */
.reveal-ready [data-anim]{opacity:0;transition:opacity .45s ease;will-change:transform,opacity;}
.reveal-ready [data-anim].in{opacity:1;animation-duration:.6s;animation-fill-mode:both;animation-timing-function:cubic-bezier(.22,.61,.36,1);}
.reveal-ready [data-anim="fade-in"].in{animation-name:ppFade;}
.reveal-ready [data-anim="fade-up"].in{animation-name:ppUp;}
.reveal-ready [data-anim="fade-down"].in{animation-name:ppDown;}
.reveal-ready [data-anim="slide-left"].in{animation-name:ppLeft;}
.reveal-ready [data-anim="slide-right"].in{animation-name:ppRight;}
.reveal-ready [data-anim="zoom-in"].in{animation-name:ppZoom;}
.reveal-ready [data-anim="pop"].in{animation-name:ppPop;animation-timing-function:cubic-bezier(.34,1.56,.64,1);}
.reveal-ready [data-anim="float"].in{animation:ppFloat 3s ease-in-out infinite;}
.reveal-ready [data-anim="pulse"].in{animation:ppPulse 2.2s ease-in-out infinite;}
.reveal-ready [data-anim="spin"].in{animation:ppSpin 7s linear infinite;}

@keyframes ppFade{from{opacity:0}to{opacity:1}}
@keyframes ppUp{from{opacity:0;transform:translateY(30px)}to{opacity:1;transform:none}}
@keyframes ppDown{from{opacity:0;transform:translateY(-30px)}to{opacity:1;transform:none}}
@keyframes ppLeft{from{opacity:0;transform:translateX(44px)}to{opacity:1;transform:none}}
@keyframes ppRight{from{opacity:0;transform:translateX(-44px)}to{opacity:1;transform:none}}
@keyframes ppZoom{from{opacity:0;transform:scale(.68)}to{opacity:1;transform:scale(1)}}
@keyframes ppPop{0%{opacity:0;transform:scale(.5)}100%{opacity:1;transform:scale(1)}}
@keyframes ppFloat{0%,100%{transform:translateY(0)}50%{transform:translateY(-9px)}}
@keyframes ppPulse{0%,100%{transform:scale(1)}50%{transform:scale(1.06)}}
@keyframes ppSpin{to{transform:rotate(360deg)}}

/* ========== SƠ ĐỒ THUẬT TOÁN (array visualizer kiểu Hello Interview) ========== */
.algo-viz{margin:24px 0;border:1px solid var(--line);border-radius:16px;background:var(--surface);padding:16px 16px 20px;}
.av-ph{display:block;text-align:center;color:var(--acc);font-family:var(--mono);font-size:12.5px;line-height:1.5;padding:18px 10px;
  border:1.5px dashed color-mix(in srgb,var(--acc) 45%,var(--line));border-radius:12px;background:color-mix(in srgb,var(--acc) 5%,var(--surface));}
.av-head{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:2px;}
.av-title{font-weight:700;font-size:14.5px;color:var(--ink);}
.av-controls{display:flex;align-items:center;gap:6px;}
.av-btn{width:34px;height:34px;border-radius:9px;border:1px solid var(--line);background:var(--surface-2);color:var(--ink-2);
  cursor:pointer;display:inline-flex;align-items:center;justify-content:center;font-size:14px;line-height:1;transition:.12s;}
.av-btn:hover{color:#fff;background:var(--acc);border-color:var(--acc);}
.av-stage{position:relative;padding:52px 4px 58px;overflow:hidden;}
.av-cells{display:flex;gap:10px;justify-content:center;flex-wrap:nowrap;}
.av-cell{position:relative;flex:0 0 auto;width:52px;height:52px;border-radius:10px;display:flex;align-items:center;justify-content:center;
  font-family:var(--mono);font-weight:700;font-size:17px;color:#fff;background:var(--av-c,#0d9488);
  transition:transform .3s ease, box-shadow .3s ease, background .3s ease, opacity .3s ease;}
.av-cell.act{transform:translateY(-7px);box-shadow:0 0 0 3px color-mix(in srgb,#fff 30%,transparent),0 14px 22px -10px rgba(0,0,0,.5);}
.av-cell.win{background:var(--acc);}
.av-cell.dim{opacity:.4;}
.av-cell.found{background:#16a34a !important;transform:translateY(-7px);box-shadow:0 0 0 3px rgba(22,163,74,.45),0 14px 24px -8px rgba(22,163,74,.6);}
/* con trỏ: nhãn + mũi tên chỉ xuống */
.av-ptr{position:absolute;top:6px;left:0;transform:translateX(-50%);display:flex;flex-direction:column;align-items:center;
  transition:left .42s cubic-bezier(.5,0,.2,1);pointer-events:none;z-index:2;}
.av-ptr .lab{font-family:var(--mono);font-size:13px;font-weight:700;margin-bottom:3px;white-space:nowrap;}
.av-ptr .arw{width:2px;height:20px;background:currentColor;border-radius:2px;position:relative;}
.av-ptr .arw::after{content:"";position:absolute;left:50%;bottom:-3px;transform:translateX(-50%);
  border-left:5px solid transparent;border-right:5px solid transparent;border-top:7px solid currentColor;}
.av-ptr.l{color:#2563eb;}
.av-ptr.r{color:#e11d48;}
/* ngoặc nối 2 ô + giá trị tính được */
.av-bracket{position:absolute;left:0;bottom:20px;height:15px;border:2px solid var(--acc);border-top:none;border-radius:0 0 8px 8px;
  transition:left .42s cubic-bezier(.5,0,.2,1),width .42s cubic-bezier(.5,0,.2,1);pointer-events:none;}
.av-bracket .val{position:absolute;left:50%;bottom:-22px;transform:translateX(-50%);font-family:var(--mono);font-weight:700;
  font-size:13px;color:var(--acc);white-space:nowrap;}
.av-status{text-align:center;font-family:var(--mono);font-size:13px;color:var(--ink-2);margin-top:8px;min-height:19px;line-height:1.4;}
@media (max-width:560px){
  .av-cell{width:40px;height:40px;font-size:14px;border-radius:8px;}
  .av-cells{gap:7px;}
  .av-stage{padding:48px 2px 54px;}
}

/* ----- Sơ đồ Cây & Đồ thị (node + cạnh SVG) ----- */
.av-canvas{position:relative;margin:6px auto 0;}
.av-edges{position:absolute;left:0;top:0;overflow:visible;pointer-events:none;z-index:0;color:var(--ink-3);}
.av-edge{stroke:var(--line);stroke-width:2;fill:none;transition:stroke .3s ease,stroke-width .3s ease;}
.av-edge.on{stroke:var(--acc);stroke-width:3.5;}
.av-node{position:absolute;transform:translate(-50%,-50%);width:44px;height:44px;border-radius:50%;box-sizing:border-box;
  display:flex;align-items:center;justify-content:center;font-family:var(--mono);font-weight:700;font-size:15px;color:#fff;
  background:var(--av-c,#0d9488);border:2px solid color-mix(in srgb,#000 14%,transparent);z-index:1;
  transition:transform .3s ease,box-shadow .3s ease,background .3s ease,opacity .3s ease;}
.av-node.dim{opacity:.42;}
.av-node.on{background:var(--acc);transform:translate(-50%,-50%) scale(1.15);
  box-shadow:0 0 0 4px color-mix(in srgb,var(--acc) 30%,transparent),0 10px 20px -8px rgba(0,0,0,.5);}
.av-node.done{background:#16a34a;}