:root{
  --bg:#F5F7FC;        /* cool paper */
  --surface:#FFFFFF;
  --ink:#141B3D;
  --indigo:#1B2A6B;    /* deep indigo */
  --indigo-2:#2E43A3;
  --mango:#FF9F1C;     /* mango orange */
  --lotus:#F2668B;     /* lotus pink */
  --soft:#E8ECF8;
  --muted:#4F5878;
  --line:#D9DEEE;
  --head:"Kanit",Tahoma,"Leelawadee UI",sans-serif;
  --body:"Bai Jamjuree",Tahoma,"Leelawadee UI",sans-serif;
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation:none!important;transition:none!important}}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--body);font-size:1.1rem;line-height:1.85}
img{max-width:100%;height:auto;display:block}
a{color:var(--indigo-2)}
a:focus-visible,summary:focus-visible{outline:3px solid var(--mango);outline-offset:3px;border-radius:4px}
.wrap{width:min(1140px,100% - 2.5rem);margin-inline:auto}
.skip{position:absolute;left:-999px;top:0;background:var(--indigo);color:#fff;padding:.5rem 1rem;z-index:10}
.skip:focus{left:1rem}

.nav{position:sticky;top:0;z-index:5;background:rgba(255,255,255,.95);backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.nav-in{display:flex;align-items:center;gap:1.5rem;min-height:62px}
.logo{font-family:var(--head);font-weight:600;font-size:1.3rem;color:var(--indigo);text-decoration:none;display:flex;align-items:center;gap:.55rem}
.logo-slip{display:grid;place-items:center;width:44px;height:30px;border-radius:6px;background:var(--mango);color:var(--indigo);font-size:.95rem;border:2px dashed var(--indigo)}
.nav nav{display:flex;gap:1.3rem;margin-left:auto}
.nav nav a{color:var(--muted);text-decoration:none;font-size:.98rem}
.nav nav a:hover{color:var(--indigo)}

.btn{display:inline-block;font-family:var(--head);font-weight:500;background:var(--mango);color:var(--indigo);text-decoration:none;padding:.8rem 1.55rem;border-radius:999px;line-height:1.3;border:2px solid var(--indigo);box-shadow:4px 4px 0 var(--indigo);transition:transform .12s,box-shadow .12s}
.btn:hover{transform:translate(-1px,-1px);box-shadow:5px 5px 0 var(--indigo)}
.btn:active{transform:translate(3px,3px);box-shadow:1px 1px 0 var(--indigo)}
.btn-o{background:#fff}
.btn-s{padding:.4rem 1.1rem;font-size:.95rem;box-shadow:3px 3px 0 var(--indigo)}
.btn-full{display:block;text-align:center}
.mid{text-align:center;margin:1.75rem 0}

.hero{background:linear-gradient(135deg,var(--indigo) 0%,var(--indigo-2) 100%);color:#fff;padding:3.25rem 0 4rem;position:relative;overflow:hidden}
.hero::after{content:"";position:absolute;right:-120px;bottom:-160px;width:420px;height:420px;border-radius:50%;background:var(--mango);opacity:.18}
.hero-in{position:relative;z-index:1;display:grid;grid-template-columns:1fr 1fr;gap:3rem;align-items:center}
.tag{display:inline-block;margin:0 0 1rem;background:var(--lotus);color:#fff;font-size:.88rem;padding:.25rem .85rem;border-radius:6px}
.hero h1{font-family:var(--head);font-weight:600;font-size:clamp(1.9rem,3.6vw,2.75rem);line-height:1.4;margin:0 0 1rem}
.intro{margin:0 0 1.6rem;color:#E4E8FA}
.cta-row{display:flex;flex-wrap:wrap;gap:1rem}
.hero .btn{border-color:#fff;box-shadow:4px 4px 0 #0B1440}
.hero .btn-o{background:transparent;color:#fff}
.note{font-size:.88rem;color:#C9D0F2;margin-top:1.2rem}
.hero-img{margin:0;position:relative}
.hero-img img{border-radius:28px 28px 28px 4px;border:4px solid #fff;box-shadow:12px 12px 0 rgba(11,20,64,.45)}
.slip{position:absolute;right:-1rem;bottom:-1.75rem;background:#fff;color:var(--ink);border-radius:10px;padding:.7rem .9rem;width:220px;box-shadow:0 12px 30px rgba(0,0,0,.25);border-top:6px solid var(--mango);transform:rotate(3deg);animation:in .7s cubic-bezier(.2,.8,.3,1.3) .2s both}
@keyframes in{from{opacity:0;transform:rotate(10deg) translateY(20px)}to{opacity:1;transform:rotate(3deg)}}
.slip-h{margin:0 0 .35rem;font-family:var(--head);color:var(--indigo);font-size:.95rem}
.slip-r{margin:0;display:flex;justify-content:space-between;align-items:center;font-size:.85rem;border-top:1px dashed var(--line);padding:.3rem 0}
.slip-r b{font-family:var(--head);font-size:1.15rem;color:var(--lotus)}

.body{max-width:46rem;margin-inline:auto;padding:3.5rem 0 4rem}
.body h2{font-family:var(--head);font-weight:600;font-size:clamp(1.45rem,2.5vw,1.9rem);line-height:1.5;margin:3.25rem 0 1rem;color:var(--indigo);padding-bottom:.4rem;background:linear-gradient(var(--mango),var(--mango)) left bottom/64px 4px no-repeat}
.body h3{font-family:var(--head);font-weight:500;font-size:1.2rem;color:var(--indigo-2);margin:1.5rem 0 .4rem;line-height:1.5}
.body p{margin:0 0 1.1rem}
.body b{color:var(--indigo)}

.rec{background:var(--surface);border:2px solid var(--indigo);border-radius:20px;padding:1.5rem;box-shadow:8px 8px 0 var(--mango)}
.rec-head{display:flex;align-items:center;gap:1rem;flex-wrap:wrap;margin-bottom:1.1rem}
.rec-head p{margin:0!important;font-family:var(--head);font-size:1.15rem;color:var(--indigo)}
.rec-logo{display:inline-flex;padding:.55rem .9rem;border-radius:12px;background:var(--indigo)}
.rec-logo img{width:129px;height:30px}
.rec-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:.6rem;margin-bottom:1.2rem}
.rec-grid p{margin:0!important;background:var(--soft);border-radius:12px;padding:.7rem .5rem;text-align:center;display:flex;flex-direction:column;line-height:1.4}
.rec-grid b{font-family:var(--head);font-size:1.15rem;color:var(--indigo)}
.rec-grid span{font-size:.85rem;color:var(--muted)}

.tbl{overflow-x:auto;margin:1.25rem 0 1.5rem;border-radius:14px;border:1px solid var(--line);background:var(--surface)}
table{border-collapse:collapse;width:100%;min-width:560px;font-size:.97rem}
caption{text-align:left;padding:.75rem 1rem;font-family:var(--head);color:var(--indigo)}
th,td{padding:.7rem .9rem;text-align:left;vertical-align:top;border-top:1px solid var(--line)}
th{background:var(--indigo);color:#fff;font-weight:500}
td:first-child{font-weight:600;color:var(--indigo)}
tbody tr:nth-child(even){background:#FAFBFE}

.day{list-style:none;padding:0;margin:1.5rem 0;position:relative}
.day::before{content:"";position:absolute;left:15px;top:6px;bottom:6px;width:3px;background:repeating-linear-gradient(var(--mango) 0 8px,transparent 8px 14px)}
.day li{position:relative;padding:0 0 1.2rem 3rem}
.day li::before{content:"";position:absolute;left:5px;top:.45rem;width:23px;height:23px;border-radius:50%;background:#fff;border:4px solid var(--indigo)}
.day b{display:block;font-family:var(--head);font-weight:500;color:var(--indigo)}
.day span{color:var(--muted);font-size:1rem}

.result{display:flex;gap:1rem;flex-wrap:wrap;margin:1.25rem 0}
.result p{margin:0!important;flex:1 1 200px;background:var(--surface);border:2px dashed var(--indigo);border-radius:14px;padding:.8rem 1rem;text-align:center}
.result span{display:block;font-size:.9rem;color:var(--muted)}
.result b{font-family:var(--head);font-size:2rem;letter-spacing:.15em;color:var(--lotus)}

.ill{margin:2.25rem 0;border-radius:20px;overflow:hidden;background:var(--surface);border:1px solid var(--line)}
.ill figcaption{padding:.7rem 1rem;font-size:.92rem;color:var(--muted)}

.three{display:grid;grid-template-columns:repeat(3,1fr);gap:.9rem;margin:1.5rem 0}
.three div{background:var(--surface);border:2px solid var(--indigo);border-radius:16px;padding:1.1rem}
.three .num{margin:0!important;width:2.4rem;height:2.4rem;border-radius:50%;display:grid;place-items:center;background:var(--lotus);color:#fff;font-family:var(--head)}
.three h3{margin:.6rem 0 .3rem}
.three p{font-size:.98rem;color:var(--muted);margin:0}

.oops{padding-left:1.4rem;margin:1.25rem 0}
.oops li{margin-bottom:.8rem;padding-left:.3rem}
.oops li::marker{font-family:var(--head);color:var(--lotus);font-weight:600}
.oops b{display:block}

.ask{list-style:none;padding:0;margin:1.25rem 0;display:grid;gap:.5rem}
.ask li{background:var(--surface);border-left:5px solid var(--lotus);border-radius:8px;padding:.7rem 1rem}

.faq details{border:2px solid var(--line);border-radius:14px;background:var(--surface);margin-bottom:.55rem}
.faq details[open]{border-color:var(--indigo)}
.faq summary{cursor:pointer;list-style:none;padding:.9rem 2.6rem .9rem 1rem;font-family:var(--head);font-weight:500;color:var(--indigo);position:relative}
.faq summary::-webkit-details-marker{display:none}
.faq summary::after{content:"+";position:absolute;right:1rem;top:.65rem;font-size:1.5rem;color:var(--mango)}
.faq details[open] summary::after{content:"−"}
.faq details p{padding:0 1rem 1rem;margin:0;color:var(--muted)}

.by{display:flex;gap:1.25rem;align-items:center;margin-top:3rem;padding:1.4rem;border-radius:20px;background:var(--surface);border:2px solid var(--indigo);box-shadow:6px 6px 0 var(--lotus)}
.by-photo{flex:none;width:96px;height:96px;border-radius:50%;object-fit:cover;border:3px solid var(--mango)}
.by-name{font-family:var(--head);color:var(--indigo);margin:0 0 .2rem!important;font-size:1.1rem}
.by p{margin:0;font-size:.98rem}

.ft{background:var(--indigo);color:#C9D0F2;padding:2.5rem 0 5.5rem;font-size:.93rem}
.ft a{color:var(--mango)}
.ft .age b{display:inline-grid;place-items:center;width:2.5rem;height:2.5rem;border-radius:50%;background:var(--mango);color:var(--indigo);margin-right:.5rem}
.ft .copy{opacity:.7}
.stick{display:none}

@media (max-width:560px){.by{flex-direction:column;align-items:flex-start}.by-photo{width:80px;height:80px}}
@media (max-width:900px){
  .nav nav{display:none}
  .nav .btn-s{margin-left:auto}
  .hero{padding:2rem 0 3.25rem}
  .hero-in{grid-template-columns:1fr;gap:2.5rem}
  .slip{right:.5rem;width:200px}
  .rec-grid{grid-template-columns:repeat(2,1fr)}
  .three{grid-template-columns:1fr}
  body{font-size:1.04rem}
  .stick{display:block;position:fixed;left:.75rem;right:.75rem;bottom:.75rem;z-index:6;text-align:center;font-family:var(--head);background:var(--mango);color:var(--indigo);border:2px solid var(--indigo);text-decoration:none;padding:.85rem;border-radius:999px;box-shadow:0 8px 24px rgba(20,27,61,.3);padding-bottom:calc(.85rem + env(safe-area-inset-bottom,0px))}
}

/* table of contents */
.toc{margin:2rem 0 0;background:#FFFFFF;border:1px solid #1B2A6B;border-radius:14px}
.toc summary{cursor:pointer;list-style:none;padding:.85rem 1.1rem;font-weight:700;color:#1B2A6B;display:flex;justify-content:space-between;align-items:center}
.toc summary::-webkit-details-marker{display:none}
.toc summary::after{content:"▾";transition:transform .2s}
.toc[open] summary::after{transform:rotate(180deg)}
.toc ol{margin:0;padding:0 1.1rem 1rem 2.4rem;columns:2;column-gap:2rem;font-size:.97rem}
.toc li{break-inside:avoid;margin:.2rem 0;color:#4F5878}
.toc a{color:#141B3D;text-decoration:none}
.toc a:hover{color:#1B2A6B;text-decoration:underline}
h2[id]{scroll-margin-top:84px}
@media (max-width:640px){.toc ol{columns:1}}