/* Bố cục: nền đen sâu, vòng sáng lam mở đầu, dải gradient dọc làm nhịp; các phần sáng xen kẽ như trang tài liệu */
:root{
  --paper:#FBF6EC; --paper-2:#F1E8D8; --card:#FFFDF8;
  --ink:#2B241C; --ink-soft:#6E6253; --line:rgba(43,36,28,.12);
  --jade:#4F7A6A; --ember:#B8862F; --ember-soft:rgba(184,134,47,.12); --lacquer:#9A3B2B;
  --blue:#B8862F; --blue-2:#9A6E22;
  --f-display:"Be Vietnam Pro",system-ui,sans-serif;
  --f-body:"Be Vietnam Pro",system-ui,sans-serif;
  --f-mono:"Be Vietnam Pro",system-ui,sans-serif;
  --gut:clamp(16px,4vw,48px); color-scheme:light;
}
.light{--paper:#F4ECDD;--paper-2:#EADFCB;--card:#FFFDF8;--ink:#2B241C;--ink-soft:#6E6253;--line:rgba(43,36,28,.13);--ember-soft:rgba(184,134,47,.1);color-scheme:light;background:var(--paper);color:var(--ink)}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
@media (prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
body{background:var(--paper);color:var(--ink);font-family:var(--f-body);font-size:15px;line-height:1.65;font-weight:400;-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
h1,h2,h3{font-family:var(--f-display);font-weight:300;line-height:1.04;letter-spacing:-.035em;text-wrap:balance;margin:0}
h3{font-weight:400;letter-spacing:-.02em}
p{margin:0}
button,input,select,textarea{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--ember);outline-offset:2px}
.wrap{max-width:1180px;margin-inline:auto;padding-inline:var(--gut)}
.eyebrow{font-family:var(--f-body);font-size:11px;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-soft);font-weight:500;display:inline-flex;align-items:center;gap:8px}
.eyebrow::before{content:"";width:6px;height:6px;background:var(--blue);flex-shrink:0}
.lede{color:var(--ink-soft);max-width:60ch}
.btn{display:inline-flex;align-items:center;gap:8px;border:1px solid var(--blue);background:var(--blue);color:#fff;padding:10px 16px;border-radius:4px;cursor:pointer;font-weight:500;font-size:13.5px;text-decoration:none;transition:background .15s,transform .15s}
.btn:hover{transform:translateY(-1px);background:#B8862F}
.btn.ghost:hover{background:var(--paper-2)}
.btn.ghost{background:transparent;color:var(--ink);border-color:var(--line)}
.btn.ember{background:var(--ink);border-color:var(--ink);color:var(--paper)}
.chip{border:1px solid var(--line);background:transparent;padding:6px 12px;border-radius:4px;font-size:13px;cursor:pointer}
.chip[aria-pressed="true"]{background:var(--blue);color:#fff;border-color:var(--blue)}
section.block{padding-block:clamp(72px,10vw,140px);border-top:1px solid var(--line);background:var(--paper);color:var(--ink)}
.sec-head{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:24px 48px;align-items:end;margin-bottom:40px}
.sec-head h2{font-size:clamp(38px,5.8vw,76px)}
@media (max-width:820px){.sec-head{grid-template-columns:1fr}}
.sample{display:inline-block;font-family:var(--f-body);font-size:11px;letter-spacing:.08em;text-transform:uppercase;border:1px dashed var(--ink-soft);color:var(--ink-soft);padding:2px 8px;border-radius:4px}