/*
  থিম: দিনের বেলা "খাতার পাতা" (রুল টানা কাগজ, লাল মার্জিন, কলমের কালি, হাইলাইটার),
  ডার্ক মোডে "ব্ল্যাকবোর্ড" (সবুজ বোর্ড, চকের সাদা ও হলুদ)।
  রঙ বদলাতে চাইলে শুধু নিচের :root-এর মানগুলো বদলান।
*/
:root {
  --paper: #fbfcfe;      /* কাগজ */
  --rule: #d6e2f2;       /* রুল টানা লাইন */
  --ink: #1b2a6b;        /* কলমের নীল কালি: শিরোনাম, লিংক, বাটন */
  --text: #20242e;       /* মূল লেখা */
  --muted: #5d6676;
  --margin: #e2463f;     /* মার্জিনের লাল দাগ, "ভুল" চিহ্ন */
  --mark: #ffe566;       /* হাইলাইটার */
  --ok: #18875c;         /* "শুদ্ধ" চিহ্ন */
  --card: #ffffff;
  --line: #dfe5ee;
  --link: var(--ink);

  --display: 'Tiro Bangla', 'Noto Serif Bengali', Georgia, serif;
  --body: 'Anek Bangla', 'Hind Siliguri', 'Noto Sans Bengali', system-ui, sans-serif;

  --m: 112px;            /* মার্জিনের প্রস্থ */
  --gap: 28px;           /* মার্জিন দাগ থেকে লেখার দূরত্ব */
  --lh: 2.1rem;          /* রুল লাইনের ব্যবধান */
}
@media (prefers-color-scheme: dark) {
  :root {
    --paper: #14231e;
    --rule: rgba(255, 255, 255, 0.07);
    --ink: #f3efe2;
    --text: #dde5dc;
    --muted: #9bb0a5;
    --margin: #ff9288;
    --mark: rgba(255, 221, 102, 0.3);
    --ok: #7fe0b3;
    --card: #1a2d27;
    --line: #2c4239;
    --link: #ffe38a;
  }
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; overflow-x: clip; background: var(--paper); color: var(--text); font-family: var(--body); font-size: var(--fs, 17px); line-height: 1.8; }
img { max-width: 100%; height: auto; }
a { color: var(--link); text-decoration-thickness: 1px; text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--link); outline-offset: 2px; border-radius: 2px; }
h1, h2, h3 { font-family: var(--display); color: var(--ink); font-weight: 400; line-height: 1.35; margin: 0 0 0.5em; }
h1 { font-size: clamp(1.9rem, 4.2vw, 2.75rem); }
h2 { font-size: 1.5rem; margin-top: 2em; }
h3 { font-size: 1.2rem; }
p { margin: 0 0 1em; }
.wrap { max-width: 1040px; margin: 0 auto; padding: 0 20px; }
.meta { color: var(--muted); font-size: 0.9rem; }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 8px; top: 8px; background: var(--paper); padding: 6px 10px; z-index: 50; }

/* ---------- হেডার ---------- */
.site-header { background: var(--paper); border-bottom: 1px solid var(--rule); box-shadow: 0 3px 0 var(--paper), 0 4px 0 var(--rule); position: sticky; top: 0; z-index: 10; }
.bar { display: flex; align-items: center; gap: 18px; min-height: 60px; position: relative; }
.brand { font-family: var(--display); font-size: 1.35rem; color: var(--ink); text-decoration: none; }
.brand img { display: block; height: 32px; width: auto; }
.nav-toggle { position: absolute; opacity: 0; pointer-events: none; }
.burger { display: none; cursor: pointer; padding: 4px 10px; border: 1.5px solid var(--ink); border-radius: 4px; color: var(--ink); line-height: 1.4; }
.nav-toggle:focus-visible + .burger { outline: 2px solid var(--link); outline-offset: 2px; }
.main-nav { margin-left: auto; }
.menu, .submenu { list-style: none; margin: 0; padding: 0; }
.menu { display: flex; gap: 22px; }
.menu li { position: relative; }
.menu a { color: var(--text); text-decoration: none; display: block; padding: 4px 0; }
.menu a:hover { color: var(--ink); box-shadow: inset 0 -0.55em 0 var(--mark); }
.submenu { display: none; position: absolute; top: 100%; left: -12px; min-width: 200px; background: var(--card); border: 1px solid var(--line); border-radius: 4px; padding: 6px 12px; box-shadow: 0 8px 24px rgba(20, 30, 70, 0.12); }
.submenu .submenu { top: -7px; left: 100%; }
.has-sub:hover > .submenu, .has-sub:focus-within > .submenu { display: block; }
.search-link { color: var(--ink); display: inline-flex; padding: 6px; }
.search-link svg { display: block; }

/* ---------- খাতার পাতা: লাল মার্জিন ---------- */
.sheet { position: relative; padding-top: 28px; padding-bottom: 64px; min-height: 62vh; padding-left: calc(20px + var(--m) + var(--gap)); }
.sheet::before { content: ''; position: absolute; top: 0; bottom: 0; left: calc(20px + var(--m)); width: 2px; background: var(--margin); opacity: 0.6; }

/* ---------- হিরো: রুল টানা কাগজ ---------- */
.hero { position: relative; margin-top: -28px; padding: calc(var(--lh) * 1.5) 0 var(--lh); }
/* রুল টানা লাইন পুরো পর্দা জুড়ে যায়, লেখা থাকে মার্জিনের ভেতরে */
.hero::before { content: ''; position: absolute; top: 0; bottom: 0; left: -100vw; right: -100vw; z-index: -1; background-image: repeating-linear-gradient(to bottom, transparent 0, transparent calc(var(--lh) - 1px), var(--rule) calc(var(--lh) - 1px), var(--rule) var(--lh)); }
.hero + h2 { margin-top: 1.1em; }
.hero h1 { font-size: clamp(2.2rem, 5.4vw, 3.5rem); line-height: calc(var(--lh) * 2); margin: 0; }
.hero .lead { font-size: 1.15rem; line-height: var(--lh); margin: 0 0 var(--lh); color: var(--muted); max-width: 44ch; }
.fix { font-family: var(--display); font-size: clamp(1.25rem, 2.6vw, 1.6rem); line-height: var(--lh); margin-bottom: var(--lh); }
.fix p { margin: 0; }
.fix .sign { display: inline-block; width: 1.4em; font-family: var(--body); font-weight: 700; }
.fix .wrong { color: var(--muted); }
.fix .wrong .sign { color: var(--margin); }
.fix .wrong .txt { background: linear-gradient(var(--margin), var(--margin)) no-repeat 0 55% / 100% 2px; }
.fix .right { color: var(--ok); }
@media (prefers-reduced-motion: no-preference) {
  .fix .wrong .txt { animation: strike 0.7s 0.5s ease-out both; }
  .fix .right { animation: write 0.5s 1.25s ease-out both; }
  @keyframes strike { from { background-size: 0 2px; } to { background-size: 100% 2px; } }
  @keyframes write { from { opacity: 0; transform: translateX(-8px); } to { opacity: 1; transform: none; } }
}

/* ---------- পটভূমির ধরন (Admin → ডিজাইন থেকে বাছাই) ---------- */
body[data-bg='plain'] .hero::before, body[data-bg='grid'] .hero::before, body[data-bg='dots'] .hero::before { display: none; }
body[data-bg='grid'] { background-image: linear-gradient(var(--rule) 1px, transparent 1px), linear-gradient(90deg, var(--rule) 1px, transparent 1px); background-size: 28px 28px; }
body[data-bg='dots'] { background-image: radial-gradient(var(--rule) 1.3px, transparent 1.4px); background-size: 22px 22px; }
body[data-bg='plain'] .hero { border-bottom: 1px solid var(--rule); }

/* ---------- মার্জিন দাগ বন্ধ থাকলে ---------- */
body[data-margin='off'] .sheet { padding-left: 20px; }
body[data-margin='off'] .sheet::before { display: none; }
body[data-margin='off'] .row { flex-wrap: wrap; }
body[data-margin='off'] .row-meta { position: static; width: 100%; text-align: left; padding: 0; display: flex; gap: 10px; align-items: center; }
body[data-margin='off'] .row-body { flex-basis: 0; }
body[data-margin='off'] .stamp { margin-top: 0; }

/* ---------- ট্যাব-চিপ (ক্যাটাগরি, ট্যাগ) ---------- */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 12px 0; }
.chip { border: 1.5px solid var(--ink); border-radius: 4px 4px 0 0; border-bottom-width: 3px; padding: 0 12px; font-size: 0.92rem; color: var(--ink); text-decoration: none; background: var(--card); }
.chip:hover { background: var(--mark); }
@media (prefers-color-scheme: dark) { .chip:hover { color: var(--ink); } }

/* ---------- পোস্ট তালিকা: তারিখ থাকে মার্জিনে ---------- */
.rows { border-top: 1px solid var(--rule); margin: 0 0 8px; }
.row { position: relative; display: flex; gap: 20px; align-items: flex-start; padding: 18px 0; border-bottom: 1px solid var(--rule); }
.row-meta { position: absolute; left: calc(-1 * (var(--m) + var(--gap))); width: calc(var(--m) - 14px); text-align: right; font-size: 0.85rem; line-height: 1.5; color: var(--muted); padding-top: 4px; }
.row-body { flex: 1; min-width: 0; }
.row h3 { margin: 0 0 2px; font-size: 1.3rem; }
.row h3 a { color: var(--ink); text-decoration: none; }
.row h3 a:hover { box-shadow: inset 0 -0.5em 0 var(--mark); }
.row p { margin: 0; color: var(--muted); max-width: 62ch; }
.row-thumb { flex: 0 0 132px; }
.row-thumb img { display: block; width: 132px; height: 88px; object-fit: cover; border-radius: 3px; border: 1px solid var(--line); }
.stamp { display: inline-block; border: 1.5px solid var(--margin); color: var(--margin); border-radius: 3px; font-size: 0.75rem; line-height: 1.5; padding: 0 6px; margin-top: 4px; }

/* ---------- ব্রেডক্রাম্ব, পেজার ---------- */
.crumbs { font-size: 0.88rem; color: var(--muted); margin-bottom: 14px; }
.crumbs a { color: var(--muted); }
.pager { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-top: 28px; }
.btn, .pager a, .share a, .share button { display: inline-block; border: 1.5px solid var(--ink); border-radius: 4px; padding: 3px 14px; background: var(--card); color: var(--ink); font: inherit; font-size: 0.95rem; text-decoration: none; cursor: pointer; }
.btn:hover, .pager a:hover, .share a:hover, .share button:hover { background: var(--mark); }

/* ---------- আর্টিকেল ---------- */
.prose { max-width: 68ch; }
.prose h1 { margin-bottom: 0.3em; }
.prose h2 { display: inline-block; background: linear-gradient(transparent 58%, var(--mark) 58%); padding: 0 4px; margin-left: -4px; }
.prose h2 + * { margin-top: 0; }
.prose > img { display: block; margin: 20px 0; border-radius: 3px; border: 1px solid var(--line); }
.prose blockquote { margin: 1.2em 0; padding: 8px 18px; border-left: 3px solid var(--ink); background: var(--card); font-family: var(--display); font-size: 1.12rem; }
.prose blockquote p:last-child { margin-bottom: 0; }
.prose ul, .prose ol { padding-left: 1.3em; margin: 0 0 1em; }
.prose li { margin: 0.2em 0; }
.prose li::marker { color: var(--margin); }
.prose code { font-family: ui-monospace, 'SFMono-Regular', Menlo, monospace; font-size: 0.9em; background: var(--card); border: 1px solid var(--line); border-radius: 3px; padding: 1px 5px; }
.prose pre { overflow: auto; background: var(--card); border: 1px solid var(--line); border-radius: 4px; padding: 14px; line-height: 1.6; }
.prose pre code { border: 0; padding: 0; background: none; }
.prose table { border-collapse: collapse; width: 100%; margin: 1.2em 0; display: block; overflow-x: auto; }
.prose th, .prose td { border: 1px solid var(--line); padding: 6px 12px; text-align: left; }
.prose th { background: var(--card); color: var(--ink); font-weight: 600; }
.prose hr { border: 0; border-top: 1px solid var(--rule); margin: 2em 0; }
.toc { border: 1px solid var(--line); border-left: 3px solid var(--mark); background: var(--card); border-radius: 3px; padding: 12px 18px; margin: 20px 0; }
.toc strong { font-family: var(--display); font-weight: 400; color: var(--ink); font-size: 1.1rem; }
.toc ul { list-style: none; margin: 6px 0 0; padding: 0; }
.toc .d3 { padding-left: 18px; font-size: 0.95rem; }
.paywall { border: 2px dashed var(--margin); border-radius: 4px; padding: 16px 18px; background: var(--card); }
.paywall p:last-child { margin-bottom: 0; }
.share { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin: 28px 0 0; }
.authorbox { border-top: 1px solid var(--rule); margin-top: 24px; padding-top: 12px; color: var(--muted); }
.related { margin-top: 48px; }
.related h2 { margin-top: 0; }

/* ---------- সার্চ ---------- */
.searchbox { width: 100%; max-width: 560px; padding: 10px 14px; font: inherit; border: 1.5px solid var(--ink); border-radius: 4px; background: var(--card); color: var(--text); margin-bottom: 18px; }
.hit { padding: 14px 0; border-bottom: 1px solid var(--rule); }
.hit h3 { margin: 0 0 2px; }
.hit p { margin: 0; color: var(--muted); }

/* ---------- ফুটার, WhatsApp ---------- */
.site-footer { border-top: 1px solid var(--rule); box-shadow: 0 -3px 0 var(--paper), 0 -4px 0 var(--rule); padding: 28px 0 36px; color: var(--muted); font-size: 0.95rem; }
.site-footer .menu { gap: 6px 20px; flex-wrap: wrap; }
.site-footer .menu a { color: var(--muted); }
.social { display: flex; gap: 16px; flex-wrap: wrap; margin: 10px 0; }
.social a { color: var(--muted); }
.site-footer p:last-child { margin: 0; }
.wa-float { position: fixed; right: 16px; bottom: 16px; background: #1faa59; color: #fff; padding: 8px 16px; border-radius: 4px; font-weight: 600; text-decoration: none; box-shadow: 0 6px 18px rgba(0, 0, 0, 0.25); z-index: 20; }

/* ---------- মোবাইল ---------- */
@media (max-width: 760px) {
  :root { --m: 0px; --gap: 16px; }
  body { font-size: calc(var(--fs, 17px) - 1px); }
  .sheet { padding-left: calc(14px + var(--gap)); padding-right: 16px; }
  body[data-margin='off'] .sheet { padding-left: 16px; }
  .sheet::before { left: 14px; }
  .wa-float { padding: 5px 12px; font-size: 0.9rem; right: 12px; bottom: 12px; }
  .search-link { order: 2; margin-left: auto; }
  .burger { display: block; order: 3; }
  .main-nav { display: none; position: absolute; top: 100%; left: 0; right: 0; background: var(--paper); border-bottom: 1px solid var(--rule); padding: 8px 20px 14px; margin: 0; box-shadow: 0 12px 24px rgba(20, 30, 70, 0.1); }
  .nav-toggle:checked ~ .main-nav { display: block; }
  .menu { flex-direction: column; gap: 2px; }
  .submenu, .submenu .submenu { display: block; position: static; border: 0; box-shadow: none; background: none; padding: 0 0 0 16px; min-width: 0; }
  .row { gap: 12px; flex-wrap: wrap; }
  .row-meta { position: static; width: 100%; text-align: left; padding: 0; display: flex; gap: 10px; align-items: center; }
  .stamp { margin-top: 0; }
  .row-thumb { flex-basis: 96px; }
  .row-thumb img { width: 96px; height: 64px; }
  .row-body { flex-basis: 0; }
}

@media print {
  .site-header, .site-footer, .share, .wa-float, .related, .sheet::before { display: none; }
  .sheet { padding-left: 0; }
}