:root{--green:#173e32;--green2:#0f2a20;--gold:#c9a45f;--gold2:#f1dca0;--ink:#213d32;--muted:#5d6f64;--paper:#f6f9f1;--line:#e3d6ae}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:"Be Vietnam Pro",system-ui,sans-serif;color:var(--ink);background:var(--paper);line-height:1.7;padding-bottom:64px}
a{color:#1d6644}
.skip{position:absolute;left:-9999px}.skip:focus{left:8px;top:8px;background:#fff;padding:8px 12px;z-index:99}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}
.kt-wrap{width:min(1080px,calc(100% - 32px));margin:0 auto}

/* header */
.kt-header{position:sticky;top:0;z-index:50;background:#fffdf5f2;backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.kt-nav{display:flex;align-items:center;gap:20px;padding:10px 0}
.kt-brand{display:flex;align-items:center;gap:10px;text-decoration:none;color:var(--green)}
.kt-brand span{font-family:"Playfair Display",serif;font-size:20px;font-weight:600;line-height:1.05;display:flex;flex-direction:column}
.kt-brand small{font:700 8.5px "Be Vietnam Pro",sans-serif;letter-spacing:2.2px;color:var(--gold);margin-top:3px}
.kt-brand-light{color:#fff}
.kt-nav nav{display:flex;gap:18px;margin-left:auto}
.kt-nav nav a{text-decoration:none;color:var(--ink);font-size:14px;font-weight:600}
.kt-nav nav a.on,.kt-nav nav a:hover{color:#1d6644;text-decoration:underline;text-underline-offset:6px;text-decoration-color:var(--gold)}
.kt-btn{display:inline-flex;align-items:center;justify-content:center;background:var(--green);color:#fff;border-radius:12px;padding:11px 18px;font-weight:700;font-size:14px;text-decoration:none;border:1px solid var(--green);white-space:nowrap}
.kt-btn:hover{background:#0f2a20}
.kt-btn-ghost{background:#fff;color:var(--green);border-color:#cdb878}
.kt-btn-ghost:hover{background:#fbf5df}
@media(max-width:820px){.kt-nav nav{display:none}.kt-btn{margin-left:auto;padding:9px 13px;font-size:13px}.kt-brand span{font-size:17px}}

/* hero */
.art-hero{background:linear-gradient(135deg,#0f2a20,#173e32 60%,#1d5744);color:#fff;padding:34px 0 38px}
.art-hero-in{max-width:860px}
.crumbs{font-size:12.5px;color:#b8d4c8;margin-bottom:14px}.crumbs a{color:#f1dca0;text-decoration:none}
.art-cat{margin:0 0 10px;font-size:11px;font-weight:800;letter-spacing:2.2px;color:var(--gold);text-transform:uppercase}
.art-hero h1{font-family:"Playfair Display",serif;font-weight:600;font-size:clamp(28px,4.4vw,44px);line-height:1.18;margin:0 0 16px;color:#fff}
.art-hero h1 em{color:var(--gold2);font-style:italic}
.art-kicker{margin:0 0 14px;color:#dcebe1;font-size:15px}
.art-kicker span{display:inline-block;background:rgba(241,220,160,.18);border:1px solid rgba(241,220,160,.4);color:var(--gold2);border-radius:999px;padding:3px 11px;font-size:11.5px;font-weight:800;letter-spacing:.4px;margin-right:6px}
.idx-lead{max-width:720px;font-size:16px}
.art-meta{margin:0;color:#b8d4c8;font-size:13px;line-height:1.6}.art-meta span{color:#8fb1a1}

/* body */
.art-body{max-width:780px;padding:32px 0 20px}
.art-body h2{font-family:"Playfair Display",serif;font-size:24px;color:var(--green);margin:36px 0 12px}
.art-sec{margin:0 0 6px}
.art-body h3{font-family:"Playfair Display",serif;font-size:25px;font-weight:600;color:var(--green);margin:34px 0 12px;padding-bottom:8px;border-bottom:2px solid var(--gold2);scroll-margin-top:84px}
.art-body p{margin:0 0 14px;font-size:16.5px;line-height:1.85}
.art-body ul,.art-body ol{margin:0 0 16px;padding-left:22px}
.art-body li{margin:0 0 7px;line-height:1.75}
.art-body strong{color:#14352a}
.art-body blockquote{margin:16px 0;padding:12px 18px;border-left:4px solid var(--gold);background:#fffbe9;border-radius:0 12px 12px 0}
.art-body blockquote p{margin:0}
.art-body em{color:#3b5a4b}
.tbl-wrap{overflow-x:auto;margin:14px 0 20px;border:1px solid var(--line);border-radius:14px;background:#fff;-webkit-overflow-scrolling:touch}
.art-body table{border-collapse:collapse;width:100%;min-width:560px;font-size:14px}
.art-body th{background:var(--green);color:#fff;text-align:left;padding:10px 12px;font-size:12px;letter-spacing:.4px;white-space:nowrap}
.art-body td{padding:10px 12px;border-top:1px solid #efe6c8;vertical-align:top;line-height:1.55}
.art-body tbody tr:nth-child(even) td{background:#fbf8ee}
.art-body td:first-child{font-weight:700;color:#14352a}
.art-sec.warn{background:#fff3ea;border:1px solid #efc8ad;border-left:5px solid #c0623d;border-radius:14px;padding:4px 20px 12px;margin:30px 0}
.art-sec.warn h3{color:#8a3a22;border-bottom-color:#efc8ad;margin-top:20px}
.art-sec.hxd{background:#eef7f0;border:1px solid #c6e0cf;border-left:5px solid #1d6644;border-radius:14px;padding:4px 20px 12px;margin:30px 0}
.art-sec.hxd h3{border-bottom-color:#c6e0cf;margin-top:20px}
.art-sec.formula{background:#fbf6e5;border:1px solid #e6d59c;border-left:5px solid var(--gold);border-radius:14px;padding:4px 20px 12px;margin:30px 0}
.art-sec.formula h3{border-bottom-color:#e6d59c;margin-top:20px}
.art-toc{background:#fff;border:1px solid var(--line);border-radius:14px;padding:12px 18px;margin:0 0 22px}
.art-toc summary{cursor:pointer;font-weight:700;color:var(--green);font-size:14px}
.art-toc ol{margin:10px 0 0;padding-left:20px;columns:2;column-gap:28px;font-size:14px}
@media(max-width:620px){.art-toc ol{columns:1}}
.art-services{margin:34px 0 10px;padding:18px 20px;background:#fff;border:1px solid var(--line);border-radius:16px}
.art-services h2{margin:0 0 12px;font-size:19px}
.chips{display:flex;flex-wrap:wrap;gap:8px}
.chips a{background:#f4edce;border:1px solid #e0c878;color:var(--green);border-radius:999px;padding:7px 14px;font-size:13.5px;font-weight:600;text-decoration:none}
.chips a:hover{background:#ecdfa8}
.art-foot{margin:26px 0;padding:16px 18px;border-top:2px solid var(--line);font-size:13.5px;color:var(--muted)}
.art-foot p{font-size:13.5px;margin:0 0 8px}
.art-foot .by{color:var(--green);font-weight:700}
.art-cta{margin:30px 0;padding:28px 26px;border-radius:20px;background:linear-gradient(135deg,#0f2a20,#1d5744);color:#fff;text-align:center}
.art-cta h2{color:#fff;margin:0 0 8px;font-size:24px}
.art-cta p{color:#cfe3d8;margin:0 0 18px;font-size:15px}
.cta-row{display:flex;gap:10px;flex-wrap:wrap;justify-content:center}
.art-cta .kt-btn{background:linear-gradient(135deg,#fff0bd,#d2ae64);color:var(--green);border-color:#d6b36a}
.art-cta .kt-btn-ghost{background:transparent;color:#fff;border-color:rgba(255,255,255,.5)}
.art-related h2{font-size:22px}
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.rel-grid a{display:flex;flex-direction:column;gap:6px;background:#fff;border:1px solid var(--line);border-radius:14px;padding:14px 16px;text-decoration:none;color:var(--ink)}
.rel-grid a:hover{border-color:var(--gold);box-shadow:0 8px 20px #173e3214}
.rel-grid span{font-size:10.5px;font-weight:800;letter-spacing:1.4px;color:var(--gold);text-transform:uppercase}
.rel-grid strong{font-size:14.5px;line-height:1.4;color:var(--green)}
@media(max-width:760px){.rel-grid{grid-template-columns:1fr}}

/* trang danh mục */
.kt-idx{padding:26px 0 20px}
.kt-tools{display:grid;gap:12px;margin-bottom:18px}
.kt-tools input{width:100%;padding:13px 16px;border:1px solid #d6c07d;border-radius:14px;font:inherit;background:#fff}
.kt-chips{display:flex;flex-wrap:wrap;gap:8px}
.kt-chips a{background:#fff;border:1px solid #d6c07d;border-radius:999px;padding:7px 14px;font-size:13px;font-weight:600;color:var(--green);text-decoration:none}
.kt-chips a:hover{background:#f4edce}
.kt-cat{margin:30px 0}
.kt-cat h2{font-family:"Playfair Display",serif;font-size:27px;color:var(--green);margin:0 0 4px}
.kt-cat>p{margin:0 0 14px;color:var(--muted);font-size:14.5px}
.kt-cat[hidden],.kt-card[hidden]{display:none}
.kt-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:14px}
.kt-card{display:flex;flex-direction:column;gap:8px;background:#fff;border:1px solid var(--line);border-radius:16px;padding:18px;text-decoration:none;color:var(--ink);transition:transform .15s,box-shadow .15s}
.kt-card:hover{transform:translateY(-3px);box-shadow:0 14px 30px #173e3218;border-color:var(--gold)}
.kt-card strong{font-family:"Playfair Display",serif;font-size:18px;line-height:1.3;color:var(--green)}
.kt-card-desc{font-size:13.5px;color:var(--muted);line-height:1.6;display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden}
.kt-card-more{margin-top:auto;font-size:13px;font-weight:700;color:#1d6644}
.kt-empty{padding:18px;background:#fff;border:1px dashed #d6c07d;border-radius:14px;text-align:center}
@media(max-width:960px){.kt-cards{grid-template-columns:1fr 1fr}}
@media(max-width:620px){.kt-cards{grid-template-columns:1fr}}

/* footer */
.kt-footer{background:var(--green2);color:#cfe3d8;padding:34px 0 20px;margin-top:30px;font-size:13.5px}
.kt-foot-grid{display:grid;grid-template-columns:1.3fr 1fr 1fr 1fr;gap:20px}
.kt-footer a{color:#f1dca0}
.kt-footer strong{color:#fff}
.kt-copy{margin:22px 0 0;padding-top:14px;border-top:1px solid #ffffff1f;color:#8fb1a1;font-size:12.5px}
@media(max-width:860px){.kt-foot-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.kt-foot-grid{grid-template-columns:1fr}}
.kt-sticky{position:fixed;left:0;right:0;bottom:0;z-index:60;display:none;background:#fffdf5;border-top:1px solid var(--line);box-shadow:0 -6px 18px #0002}
.kt-sticky a{flex:1;text-align:center;padding:11px 4px;font-size:12.5px;font-weight:700;color:var(--green);text-decoration:none}
.kt-sticky-book{background:var(--gold);color:var(--green2)!important}
@media(max-width:820px){.kt-sticky{display:flex}body{padding-bottom:58px}}
@media print{.kt-header,.kt-sticky,.art-cta,.art-related,.kt-footer{display:none}.art-hero{background:#fff;color:#000;padding:0}.art-hero h1{color:#000}}

/* bảng thành thẻ trên màn hẹp */
@media(max-width:640px){
  .tbl-wrap{border:0;background:transparent;overflow:visible;margin:12px 0 18px}
  .art-body table,.art-body tbody,.art-body tr,.art-body td{display:block;width:100%;min-width:0}
  .art-body thead{display:none}
  .art-body tr{background:#fff;border:1px solid var(--line);border-radius:14px;margin-bottom:12px;overflow:hidden;padding-bottom:6px}
  .art-body tbody tr:nth-child(even) td{background:transparent}
  .art-body td{border:0;padding:6px 14px;font-size:14px}
  .art-body td:first-child{background:#f4edce!important;font-family:"Playfair Display",serif;font-size:16.5px;padding:10px 14px;margin-bottom:4px}
  .art-body td::before{content:attr(data-label);display:block;font-size:10.5px;font-weight:800;letter-spacing:1.1px;color:#8a5a14;text-transform:uppercase;margin-bottom:1px}
  .art-body td:first-child::before{display:none}
}