/* Màu + phông theo bộ nhận diện Bài 3 (Agent boss/Bài 3/assets/brand.css) */
:root{
  --than:#231F20; --kem:#F6F1EA; --dong:#D49A6A; --dong-dam:#8A4B2E; --nude:#E6D3C3;
  --xam-am:#6E6662; --xam-tro:#A39A94; --vien-toi:rgba(246,241,234,.14); --vien-sang:rgba(35,31,32,.12);
  --trang:#FFFFFF; --xanh:#2E6B4F; --do:#A23B2A;
  --font:'Be Vietnam Pro',system-ui,sans-serif; color-scheme:light;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--kem);color:var(--than);font-family:var(--font);line-height:1.6;font-size:16px}
img{max-width:100%;display:block}
a{color:var(--dong-dam)}
.wrap{max-width:1080px;margin:0 auto;padding:0 16px}
.eyebrow{font-size:12px;font-weight:600;letter-spacing:.14em;text-transform:uppercase;color:var(--dong-dam)}
h1,h2,h3{line-height:1.25;margin:0}
h2{font-size:clamp(24px,4.5vw,34px);font-weight:800;margin:6px 0 12px}
h3{font-size:18px;font-weight:700}
.lead{color:var(--xam-am);max-width:640px;margin:0}
section{padding:64px 0}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;min-height:48px;padding:0 22px;border-radius:12px;
  font:600 15px var(--font);text-decoration:none;border:0;cursor:pointer;transition:transform .15s,background .15s}
.btn:active{transform:scale(.98)}
.btn-dong{background:var(--dong);color:var(--than)}
.btn-dong:hover{background:#E0AC80}
.btn-vien{background:transparent;color:var(--kem);box-shadow:inset 0 0 0 1.5px var(--vien-toi)}
.btn-vien:hover{box-shadow:inset 0 0 0 1.5px var(--dong)}
.btn-than{background:var(--than);color:var(--kem)}
.btn-than:hover{background:#3a3435}
.btn[disabled]{opacity:.5;cursor:not-allowed}
:focus-visible{outline:2px solid var(--dong-dam);outline-offset:2px}

/* Thanh đầu trang */
.top{position:sticky;top:0;z-index:20;background:rgba(35,31,32,.96);backdrop-filter:blur(8px);border-bottom:1px solid var(--vien-toi)}
.top .wrap{display:flex;align-items:center;justify-content:space-between;height:60px}
.brand{display:flex;align-items:center;gap:10px;color:var(--kem);text-decoration:none;font-weight:700;font-size:15px}
.brand img{height:28px;width:auto}
.top nav{display:flex;gap:4px}
.top nav a{color:var(--xam-tro);text-decoration:none;font-size:14px;padding:8px 10px;border-radius:8px}
.top nav a:hover{color:var(--kem)}
.top nav a.cta{color:var(--than);background:var(--dong);font-weight:600}
@media (max-width:640px){.top nav a:not(.cta){display:none}}

/* Họa tiết nét chém xiên của logo */
.slash{position:absolute;pointer-events:none;height:2px;background:linear-gradient(90deg,transparent,var(--dong),transparent);transform:rotate(-20deg);opacity:.5}