/* Giao diện trang Blog & trang phụ – dùng chung token với trang chủ */
:root{
  --teal-900:#04333a;--teal-800:#074751;--teal-700:#0d5962;--gold-500:#f2b719;--gold-400:#f6c94a;
  --ivory-50:#faf8f2;--ivory-100:#f3eee1;--ivory-200:#e8dfc8;--ink-900:#24313a;--ink-600:#4c5a63;
  --bg-page:var(--ivory-50);--bg-alt:var(--ivory-100);--surface:#fff;--line:var(--ivory-200);
  --text:var(--ink-900);--text-muted:var(--ink-600);--text-brand:var(--teal-800);--link:var(--teal-700);
  --accent:var(--gold-500);--on-accent:var(--teal-900);--accent-hover:var(--gold-400);
  --radius:12px;--wrap:1200px;
  --f-head:"Playfair Display",Georgia,serif;--f-body:"Be Vietnam Pro",system-ui,sans-serif;
}
@media (prefers-color-scheme:dark){:root{
  --bg-page:#121a1c;--bg-alt:#172225;--surface:#1e2b2e;--line:#2c3c40;--text:#e9e4d8;--text-muted:#a9b5b3;
  --text-brand:#9fd6d9;--link:#9fd6d9;--accent:#f6c94a;--accent-hover:#f9d771}}
*{box-sizing:border-box;margin:0;padding:0}
[hidden]{display:none!important}
html{scroll-behavior:smooth;scroll-padding-top:90px}
body{font-family:var(--f-body);font-size:17px;line-height:1.75;color:var(--text);background:var(--bg-page);-webkit-font-smoothing:antialiased}
img{display:block;max-width:100%;height:auto}
a{color:inherit;text-decoration:none}
.wrap{max-width:var(--wrap);margin:0 auto;padding:0 16px}
:focus-visible{outline:3px solid var(--accent);outline-offset:3px;border-radius:4px}
.btn{display:inline-flex;align-items:center;justify-content:center;min-height:48px;padding:0 26px;border-radius:8px;font:600 15px var(--f-body);border:2px solid transparent;cursor:pointer;transition:background .2s,transform .2s}
.btn-main{background:var(--accent);color:var(--on-accent);box-shadow:0 8px 24px rgba(242,183,25,.3)}
.btn-main:hover{background:var(--accent-hover);transform:translateY(-2px)}
.btn-line{border-color:var(--link);color:var(--link)}
.btn-line:hover{background:var(--link);color:var(--bg-page)}

/* header */
.topbar{background:var(--teal-900);color:#c9d6d4;font-size:13px}
.topbar .wrap{display:flex;justify-content:flex-end;gap:20px;min-height:36px;align-items:center}
.topbar a{color:#f5efe0}
header.site{position:sticky;top:0;z-index:50;background:var(--teal-800);box-shadow:0 2px 12px rgba(0,0,0,.18)}
.nav{display:flex;align-items:center;justify-content:space-between;min-height:76px;gap:16px}
.nav .logo img{height:56px;width:auto}
.nav ul{list-style:none;display:flex;gap:2px}
.nav ul a{display:block;padding:10px 12px;font-family:var(--f-head);font-size:14px;letter-spacing:.05em;text-transform:uppercase;color:#f5efe0}
.nav ul a:hover,.nav ul a[aria-current]{color:var(--gold-500)}
.burger{display:none;background:none;border:0;color:#f5efe0;width:48px;height:48px;cursor:pointer}
.drawer{display:none}

/* blog index */
.bhero{background:var(--teal-800) url("/images/bg_footer.jpg") center/cover;color:#f5efe0;padding:64px 0 56px;text-align:center}
.bhero h1{font-family:var(--f-head);font-weight:600;font-size:clamp(32px,4.4vw,48px);line-height:1.2}
.bhero p{max-width:680px;margin:12px auto 0;color:#c9d6d4}
.eyebrow{display:block;font-size:13px;letter-spacing:.22em;text-transform:uppercase;font-weight:600;margin-bottom:8px;color:#c9d6d4}
.filters{display:flex;flex-wrap:wrap;justify-content:center;gap:8px;margin:32px 0}
.filters button{min-height:44px;padding:0 20px;border-radius:999px;border:1.5px solid var(--line);background:var(--surface);color:var(--text-muted);font:600 15px var(--f-body);cursor:pointer}
.filters button[aria-pressed="true"]{background:var(--teal-800);border-color:var(--teal-800);color:#faf8f2}
.posts{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;padding-bottom:72px}
.post{display:flex;flex-direction:column;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);overflow:hidden;transition:border-color .2s,transform .2s}
.post:hover{border-color:var(--link);transform:translateY(-3px)}
.post img{width:100%;aspect-ratio:16/10;object-fit:cover}
.post .pb{padding:18px;display:flex;flex-direction:column;gap:8px;flex:1}
.post .meta{font-size:13px;color:var(--text-muted)}
.post h2,.post h3{font-size:18px;line-height:1.4;font-weight:600;color:var(--text)}
.post p{font-size:15px;line-height:1.6;color:var(--text-muted)}
.post .more{margin-top:auto;font-weight:600;color:var(--link);font-size:15px}

/* bài viết */
.crumb{font-size:14px;color:var(--text-muted);padding:20px 0 0}
.crumb a{color:var(--link)}
.art{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:48px;padding:16px 0 64px}
.art h1{font-family:var(--f-head);font-weight:600;font-size:clamp(30px,4vw,44px);line-height:1.22;color:var(--text-brand);margin:8px 0 12px}
.art .meta{font-size:14px;color:var(--text-muted);margin-bottom:24px}
.art .cover{border-radius:var(--radius);overflow:hidden;margin-bottom:28px}
.body h2{font-family:var(--f-head);font-weight:600;font-size:clamp(24px,2.6vw,30px);line-height:1.3;color:var(--text-brand);margin:40px 0 12px}
.body h3{font-size:20px;line-height:1.4;font-weight:700;margin:28px 0 8px;color:var(--text)}
.body p{margin:0 0 16px}
.body ul{margin:0 0 18px 22px}
.body li{margin-bottom:6px}
.body figure{margin:24px 0;border-radius:var(--radius);overflow:hidden}
.body figure figcaption{font-size:14px;color:var(--text-muted);padding:8px 2px 0;text-align:center}
.cta{margin:36px 0;padding:24px;border-radius:var(--radius);background:var(--teal-800);color:#f5efe0;display:flex;gap:20px;align-items:center;justify-content:space-between;flex-wrap:wrap}
.cta b{font-family:var(--f-head);font-size:22px;display:block}
.cta p{margin:4px 0 0;color:#c9d6d4;font-size:15px}
aside .box{position:sticky;top:100px;background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:20px}
aside h2{font-size:15px;letter-spacing:.08em;text-transform:uppercase;color:var(--text-muted);margin-bottom:10px}
.toc{list-style:none;display:grid;gap:8px;font-size:15px;line-height:1.45;margin-bottom:20px}
.toc a{color:var(--link)}
.toc a:hover{text-decoration:underline}
.related{border-top:1px solid var(--line);padding:48px 0 72px}
.related h2{font-family:var(--f-head);font-size:28px;color:var(--text-brand);margin-bottom:20px}

/* trang chữ (chính sách) */
.page{max-width:820px;padding:40px 16px 72px}
.page h1{font-family:var(--f-head);font-size:clamp(30px,4vw,40px);color:var(--text-brand);margin-bottom:16px}
.page h2{font-size:21px;margin:28px 0 8px;color:var(--text-brand)}
.page p,.page li{margin-bottom:10px}
.page ul{margin-left:22px}

/* footer */
footer{background:var(--teal-900) url("/images/bg_footer.jpg") center/cover;color:#c9d6d4;padding:48px 0 0;font-size:15px}
.ft{display:grid;grid-template-columns:1.4fr 1fr 1.4fr;gap:32px}
.ft img{height:64px;width:auto;margin-bottom:12px}
.ft h4{font-family:var(--f-head);color:#faf8f2;font-size:18px;margin-bottom:12px;letter-spacing:.06em}
.ft ul{list-style:none;display:grid;gap:8px}
.ft a:hover{color:var(--gold-500)}
.copy{margin-top:40px;border-top:1px solid rgba(255,255,255,.14);padding:16px 0;display:flex;justify-content:space-between;flex-wrap:wrap;gap:8px;font-size:13px}
.copy nav{display:flex;gap:18px}
.float{position:fixed;right:16px;bottom:16px;z-index:60;display:flex;flex-direction:column;gap:10px}
.float a{width:52px;height:52px;border-radius:50%;display:grid;place-items:center;color:#fff;box-shadow:0 6px 18px rgba(0,0,0,.25)}
.float .zl{background:var(--teal-700);font:700 13px var(--f-body)}
.float .ph{background:var(--teal-700)}

@media (max-width:980px){.posts{grid-template-columns:1fr 1fr}.art{grid-template-columns:1fr}aside .box{position:static}aside{order:-1}.ft{grid-template-columns:1fr 1fr}}
@media (max-width:860px){
  .nav ul{display:none}.burger{display:grid;place-items:center}.nav .logo img{height:46px}.nav{min-height:64px}
  .drawer{display:block;position:fixed;inset:64px 0 auto 0;background:var(--teal-800);max-height:0;overflow:hidden;transition:max-height .3s;z-index:49}
  .drawer.open{max-height:80vh;overflow:auto}
  .drawer a{display:block;padding:14px 20px;border-top:1px solid rgba(255,255,255,.1);color:#f5efe0;font-family:var(--f-head);text-transform:uppercase;font-size:15px}
  .float a{width:44px;height:44px}.float{gap:8px;right:12px;bottom:12px}
}
@media (max-width:560px){.posts{grid-template-columns:1fr}.ft{grid-template-columns:1fr}body{font-size:16px}.cta{padding:20px}}
@media (prefers-reduced-motion:reduce){*,*::before,*::after{transition:none!important;scroll-behavior:auto!important}}