:root{
  --paper:#F1F6EE;--surface:#FFFFFF;--ink:#17281B;
  --leaf:#2E7D32;--leaf-deep:#173D2C;--leaf-soft:#DCEFD6;
  --lime:#7CB342;--sun:#D99A0B;--muted:#5E7361;--line:#D3E2CD;
  --display:'Bai Jamjuree','Noto Sans Thai',sans-serif;
  --body:'IBM Plex Sans Thai Looped','Noto Sans Thai',sans-serif;
  --mono:'IBM Plex Mono',ui-monospace,monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:70px}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--body);
  font-size:17px;line-height:1.84;-webkit-font-smoothing:antialiased}
img{max-width:100%;display:block}
.wrap{max-width:800px;margin:0 auto;padding:0 22px}
.eyebrow{font-family:var(--mono);font-size:11.5px;letter-spacing:.17em;text-transform:uppercase;color:#B7E4A8}

/* rail */
.rail{background:rgba(241,246,238,.95);border-bottom:1px solid var(--line);position:sticky;top:0;z-index:40;backdrop-filter:blur(8px)}
.rail-in{max-width:800px;margin:0 auto;padding:7px 22px;min-height:52px;display:flex;
  align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}
.rail-home{display:inline-flex;align-items:center;gap:8px;text-decoration:none;
  background:linear-gradient(120deg,#3D8B3D,#2E7D32);color:#fff;border-radius:6px;padding:7px 13px 7px 11px}
.rail-home:hover{filter:brightness(1.1)}
.rh-arrow{font-size:16px;opacity:.85}
.rh-text{font-family:var(--display);font-weight:600;font-size:14.5px;line-height:1.15;white-space:nowrap}
.rh-text b{display:block;font-weight:700;font-size:11.5px;letter-spacing:.14em;
  text-transform:uppercase;color:#B7E4A8;font-family:var(--mono)}
.rail-nav{display:flex;gap:5px;overflow-x:auto;scrollbar-width:none}
.rail-nav::-webkit-scrollbar{display:none}
.rail-nav a{font-family:var(--display);font-weight:600;font-size:14px;color:var(--leaf-deep);
  text-decoration:none;padding:6px 11px;border-radius:5px;border:1px solid transparent;white-space:nowrap}
.rail-nav a:hover{background:var(--leaf-soft);border-color:#A9D69C}
.rail-nav a.on{background:var(--leaf-deep);border-color:var(--leaf-deep);color:#fff}

/* head */
.phead{background:linear-gradient(135deg,#2E7D32 0%,#1E6B3A 55%,#17553C 100%);
  color:#fff;padding:44px 0 38px;position:relative;overflow:hidden}
.phead::after{content:'';position:absolute;left:0;right:0;bottom:0;height:4px;
  background:linear-gradient(90deg,#9CCC65 0 34%,#7CB342 0 67%,#D99A0B 0 100%)}
.phead h1{font-family:var(--display);font-weight:700;font-size:clamp(26px,4.6vw,40px);
  margin:10px 0 0;line-height:1.2}
.phead.cover{padding:46px 0 40px}
.hin{display:grid;grid-template-columns:1fr 160px;gap:26px;align-items:start}
.sub{color:#CBE6C6;margin:14px 0 0;max-width:38em;font-size:16px;line-height:1.7}
.by{margin-top:18px;padding-top:14px;border-top:1px solid rgba(255,255,255,.22);
  display:flex;flex-wrap:wrap;gap:4px 22px;font-family:var(--mono);font-size:12px;color:#A7CBA4}
.by b{color:#fff;font-weight:500}
.cov img{border-radius:4px;border:1px solid rgba(255,255,255,.3);box-shadow:0 8px 22px rgba(0,0,0,.22)}
.acts{display:flex;gap:9px;flex-wrap:wrap;margin-top:20px}
.btn{display:inline-block;text-decoration:none;font-family:var(--display);font-weight:600;
  font-size:14.5px;padding:9px 16px;border-radius:5px;background:#fff;color:#1E6B3A}
.btn.ghost{background:rgba(255,255,255,.16);color:#fff;border:1px solid rgba(255,255,255,.55)}

/* prose */
.prose{padding:40px 0 8px}
.prose p{margin:0 0 19px}
.prose h2{font-family:var(--display);font-weight:700;font-size:clamp(20px,3.4vw,25px);
  line-height:1.35;margin:44px 0 14px;padding-left:15px;border-left:4px solid var(--leaf)}
.prose h3{font-family:var(--display);font-weight:600;font-size:18.5px;margin:32px 0 9px;color:var(--leaf-deep)}
.prose h3::before{content:'';display:inline-block;width:8px;height:8px;background:var(--lime);
  border-radius:2px;margin-right:10px;vertical-align:1px;transform:rotate(45deg)}
.prose ul{margin:0 0 20px;padding-left:22px}
.prose li{margin-bottom:9px}
.prose li::marker{color:var(--lime)}
.intro{padding:34px 0 10px;border-bottom:1px solid var(--line)}
.intro p:first-of-type{font-size:18.5px;color:var(--leaf-deep)}
blockquote{margin:28px 0;background:var(--surface);border-left:5px solid var(--sun);
  border-radius:0 4px 4px 0;padding:20px 22px}
blockquote p{font-family:var(--display);font-weight:500;font-size:17.5px;line-height:1.72;margin:0;color:var(--leaf-deep)}

/* figures & tables */
.figs{margin:30px 0}
.figs figure{margin:0 0 10px}
.figs img{width:100%;border-radius:4px;border:1px solid var(--line);background:#fff}
.figs figcaption{font-family:var(--mono);font-size:11.5px;color:var(--muted);text-align:center;line-height:1.55}
.tw{overflow-x:auto;margin:26px 0;border:1px solid var(--line);border-radius:5px;background:#fff}
table{border-collapse:collapse;width:100%;min-width:480px;font-size:14.5px}
th,td{padding:10px 13px;text-align:left;border-bottom:1px solid var(--line);vertical-align:top;line-height:1.6}
th{font-family:var(--display);font-weight:600;font-size:13.5px;background:var(--leaf-soft);color:var(--leaf-deep)}

/* toc */
.grp{padding:30px 0 0}
.grp h2{font-family:var(--display);font-weight:700;font-size:19px;margin:0 0 11px;color:var(--leaf-deep)}
.grp h2::before{content:'';display:inline-block;width:9px;height:9px;background:var(--lime);
  border-radius:2px;margin-right:10px;vertical-align:1px;transform:rotate(45deg)}
.rows{display:grid;gap:8px}
.row{display:flex;align-items:center;gap:16px;background:var(--surface);border:1px solid var(--line);
  border-radius:6px;padding:14px 17px;text-decoration:none;color:inherit;transition:border-color .15s,transform .15s}
.row:hover{border-color:var(--leaf);transform:translateX(3px)}
.row.key{border-left:4px solid var(--sun)}
.rb{flex:1;min-width:0}
.rn{display:block;font-family:var(--display);font-weight:600;font-size:16.5px;line-height:1.4}
.rn em{font-style:normal;font-family:var(--mono);font-size:10px;letter-spacing:.08em;
  background:#FBEFD2;color:#8A5F06;padding:2px 7px;border-radius:3px;margin-left:8px;vertical-align:2px}
.rd{display:block;font-size:14px;color:var(--muted);line-height:1.6;margin-top:2px}
.rm{flex:none;font-family:var(--mono);font-size:11.5px;color:var(--leaf)}

/* pager */
.pager{display:flex;justify-content:space-between;gap:14px;flex-wrap:wrap;
  margin:50px 0 10px;padding-top:24px;border-top:1px solid var(--line)}
.pn{flex:1 1 44%;text-decoration:none;color:var(--leaf-deep);background:var(--surface);
  border:1px solid var(--line);border-radius:5px;padding:13px 15px;
  font-family:var(--display);font-weight:600;font-size:15px;line-height:1.4}
.pn:hover{border-color:var(--leaf)}
.pn span{display:block;font-family:var(--mono);font-weight:500;font-size:11px;
  letter-spacing:.1em;text-transform:uppercase;color:var(--muted);margin-bottom:4px}
.pn.next{text-align:right}

/* progress */
.progress{position:fixed;top:0;left:0;right:0;height:3px;z-index:60;pointer-events:none}
.progress i{display:block;height:100%;width:0;background:linear-gradient(90deg,#9CCC65,#2E7D32,#D99A0B)}

.foot{background:var(--leaf-deep);color:#9FC3A5;padding:36px 0 44px;margin-top:54px;font-size:14px;line-height:1.72}
.foot b{color:#fff;font-weight:500}
.foot p{margin:0 0 12px}

@media(max-width:640px){
  body{font-size:16.5px}
  .hin{grid-template-columns:1fr}
  .cov{max-width:128px}
  .rm{display:none}
  .pn{flex:1 1 100%}
  .pn.next{text-align:left}
}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}.row:hover{transform:none}.progress{display:none}}
a:focus-visible{outline:2px solid var(--sun);outline-offset:3px}
@media print{.rail,.pager,.progress{display:none}body{background:#fff;font-size:11pt}}