/* Moats · article.css — kiểu bài đọc cho /phuong-phap/ (Agent E).
   Nạp SAU /assets/moats.css. Khối @layer fallback chỉ là token dự phòng; header/footer do moats.css lo. */

@layer fallback {
  :root{--ink:#0E1726;--ink2:#1C2738;--muted:#5B6576;--line:#E3E7EC;--bg:#F3F5F7;--mint:#12A37F;--ok:#0B7A5E;--okbg:#E3F4EE;--warn:#7A3B00;--warnbg:#FCEFD9;--orange:#E08A2E;--bad:#8F1C13;--badbg:#FBE4E2}
  body{margin:0;font-family:'Be Vietnam Pro',system-ui,-apple-system,sans-serif;color:var(--ink);background:var(--bg);line-height:1.6}
  .sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
}

/* ---------- tiện ích ---------- */
.skip{position:absolute;left:-999px;top:8px;background:#fff;color:var(--ink);padding:8px 12px;border-radius:8px;z-index:10}
.skip:focus{left:8px}
.site-footer .foot-small{font-size:13px;opacity:.85;margin:6px 0 0}

/* ---------- khung bài ---------- */
.art{padding:28px 20px 56px;overflow-wrap:break-word}
.art-grid{max-width:1040px;margin:0 auto;display:grid;grid-template-columns:minmax(0,1fr);gap:40px}
.art-body{max-width:720px;width:100%;margin:0 auto;min-width:0;font-size:17px}
.art-side{display:none}
@media (min-width:1100px){
  .art-grid{grid-template-columns:220px minmax(0,720px);justify-content:center}
  .art-side{display:block;position:sticky;top:20px;align-self:start}
  .art-body{margin:0}
}
.side-lbl,.toc-lbl,.go-lbl{font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin:0 0 10px}
.series{list-style:none;margin:0;padding:0;display:grid;gap:2px}
.series a{display:flex;gap:10px;align-items:center;padding:7px 10px;border-radius:10px;color:var(--ink);text-decoration:none;font-size:14px;font-weight:500}
.series a:hover{background:#fff}
.series i{font-style:normal;font-variant-numeric:tabular-nums;width:22px;height:22px;border-radius:7px;display:grid;place-items:center;background:var(--line);font-size:12px;font-weight:700;color:var(--muted);flex:none}
.series li[aria-current] a{background:#fff;font-weight:700;box-shadow:inset 3px 0 0 var(--mint)}
.series li[aria-current] i{background:var(--mint);color:#fff}

.crumbs{font-size:14px;color:var(--muted);margin:0 0 18px;display:flex;flex-wrap:wrap;gap:6px}
.crumbs a{color:var(--muted)}
.kicker{margin:0 0 8px;color:var(--ok);font-weight:700;font-size:14px}
.art-body h1{font-size:clamp(30px,5vw,42px);line-height:1.15;letter-spacing:-.02em;margin:0 0 14px}
.lede{font-size:19px;color:var(--ink2);margin:0 0 24px;line-height:1.55}
.art-body h2{font-size:clamp(22px,3vw,27px);line-height:1.25;letter-spacing:-.01em;margin:44px 0 12px;scroll-margin-top:16px}
.art-body h3{font-size:18px;margin:4px 0 10px}
.art-body p,.art-body li{color:var(--ink)}
.art-body a{color:#0B5F8A;text-underline-offset:2px}
.art-body a:hover{color:#08425F}
.art-body ul,.art-body ol{padding-left:1.3em}
.art-body li{margin:0 0 6px}
.art-body strong{font-weight:700}

/* mục lục */
.toc{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;margin:0 0 8px}
.toc ol{margin:0;padding-left:1.3em;columns:2;column-gap:28px;font-size:15px}
.toc li{margin:0 0 4px;break-inside:avoid}
.toc a{color:var(--ink);text-decoration:none}
.toc a:hover{color:var(--ok);text-decoration:underline}
@media (max-width:600px){.toc ol{columns:1}}

/* công thức */
.formula{font-variant-numeric:tabular-nums;background:var(--ink);color:#E6ECF3;border-radius:12px;padding:12px 16px;font-weight:600;font-size:15.5px;line-height:1.5;margin:14px 0}
.formula sup{color:#7FE0C3}
li .formula{margin:8px 0}

/* bảng */
.art-tbl{overflow-x:auto;-webkit-overflow-scrolling:touch;margin:16px 0 20px;border:1px solid var(--line);border-radius:12px;background:#fff;max-width:100%}
.art-tbl table{border-collapse:collapse;width:100%;font-size:15px;min-width:0}
.art-tbl caption{caption-side:top;text-align:left;font-size:13px;color:var(--muted);padding:10px 14px 0}
.art-tbl th,.art-tbl td{padding:10px 14px;text-align:left;vertical-align:top;border-bottom:1px solid var(--line)}
.art-tbl th{font-size:13px;font-weight:700;color:var(--muted);background:var(--bg);white-space:nowrap}
.art-tbl tr:last-child td{border-bottom:0}
.num-tbl td{font-variant-numeric:tabular-nums}
.bank-tbl td:first-child,.sign-tbl td:first-child{font-weight:700;color:var(--muted);width:2.2em}
.bank-tbl td:nth-child(2),.sign-tbl td:nth-child(2){font-weight:600}
.bad-tbl td:first-child{color:var(--bad)}
.ok-tbl td:first-child{color:var(--ok)}
.t-ok,.t-bad,.t-warn{display:inline-block;font-size:13px;font-weight:700;border-radius:999px;padding:2px 10px;white-space:nowrap}
.t-ok{background:var(--okbg);color:var(--ok)}
.t-bad{background:var(--badbg);color:var(--bad)}
.t-warn{background:var(--warnbg);color:var(--warn)}
@media (max-width:600px){
  .art-body{font-size:16px}
  .art-tbl table{font-size:14px}
  .art-tbl th,.art-tbl td{padding:9px 10px}
  .art-tbl th{white-space:normal}
}

/* hộp ví dụ, ghi nhớ, cẩn thận */
.ex,.mem,.caution{border-radius:14px;padding:18px 20px;margin:22px 0}
.ex{background:#fff;border:1px solid var(--line);border-left:4px solid var(--mint)}
.ex-lbl,.mem-lbl,.caution-lbl{margin:0 0 6px;font-size:12px;font-weight:800;letter-spacing:.06em;text-transform:uppercase}
.ex-lbl{color:var(--ok)}
.ex .art-tbl{margin:12px 0}
.ex p:last-child{margin-bottom:0}
.mem{background:var(--okbg);color:var(--ink)}
.mem-lbl{color:var(--ok)}
.mem p{margin:0;font-weight:600}
.caution{background:var(--warnbg)}
.caution-lbl{color:var(--warn)}
.caution p{margin:0;color:var(--warn)}
@media (max-width:600px){.ex,.mem,.caution{padding:16px}}

/* danh sách bước */
ol.road{list-style:none;padding:0;margin:16px 0;counter-reset:r;display:grid;gap:10px}
ol.road li{counter-increment:r;position:relative;background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px 16px 12px 56px;margin:0}
ol.road li::before{content:counter(r);position:absolute;left:14px;top:12px;width:28px;height:28px;border-radius:8px;background:var(--ink);color:#fff;display:grid;place-items:center;font-weight:800;font-size:14px}
ol.road a{text-decoration:none}
.steps-list li b{color:var(--ok)}

/* 4 chữ M */
.m4{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,300px),1fr));gap:10px;margin:16px 0}
.m4 p{margin:0;background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px 14px;font-size:15px;color:var(--muted)}
.m4 b{display:block;color:var(--ink);font-size:16px}

/* áp dụng ngay */
.go{margin:36px 0 0;padding:18px;background:var(--ink);border-radius:16px}
.go .go-lbl{color:#9FB0C5}
.go ul{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,200px),1fr));gap:10px}
.go li{margin:0}
.go a{display:block;height:100%;background:var(--ink2);border:1px solid #2B3850;border-radius:12px;padding:12px 14px;text-decoration:none}
.go a:hover{border-color:var(--mint)}
.go b{display:block;color:#fff;font-size:15px}
.go span{display:block;color:#AEB9C8;font-size:13.5px;line-height:1.45;margin-top:2px}

/* trước / sau */
.pager{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:36px 0 0}
.pager a{display:block;background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 16px;text-decoration:none;min-width:0}
.pager a:hover{border-color:var(--mint)}
.pager span{display:block;font-size:13px;color:var(--muted)}
.pager b{display:block;color:var(--ink);font-size:15.5px;line-height:1.35}
.pager .next{text-align:right}
@media (max-width:520px){.pager{grid-template-columns:1fr}.pager .empty{display:none}.pager .next{text-align:left}}