:root{
  --bg:#faf8f5;--fg:#16180f;--pri:#4b5c39;--pri-d:#34421f;--acc:#c9a96a;--acc-d:#8a6a2c;
  --mut:#efeadf;--bd:#ddd7ca;--soft:#5c5f52;--card:#fffefb;
  --ease:cubic-bezier(.16,1,.3,1);
  --sh-1:0 1px 2px rgba(40,48,25,.06),0 2px 6px rgba(40,48,25,.05);
  --sh-2:0 2px 4px rgba(40,48,25,.06),0 14px 32px -8px rgba(40,48,25,.18);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;scroll-padding-top:84px;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.7 Inter,system-ui,sans-serif;font-feature-settings:"tnum" 0;text-rendering:optimizeLegibility}
::selection{background:var(--acc);color:#1d1a10}
*{scrollbar-color:var(--pri) var(--mut);scrollbar-width:thin}
h1,h2,h3,h4{font-family:'Playfair Display',Georgia,serif;line-height:1.22;margin:0 0 .55em;color:var(--pri-d);text-wrap:balance;letter-spacing:-.01em}
h1{font-size:clamp(2rem,4.2vw,3.1rem);font-weight:700}
h2{font-size:clamp(1.35rem,2.2vw,1.65rem);margin-top:2.2em;font-weight:600}
h3{font-size:1.15rem;font-weight:600}
a{color:var(--pri);text-underline-offset:3px;text-decoration-thickness:1px}
a:hover{color:var(--pri-d);text-decoration-thickness:2px}
img{max-width:100%;height:auto;display:block}
sub,sup{font-size:.72em;line-height:0;position:relative;vertical-align:baseline}
sub{bottom:-.25em}sup{top:-.45em}
:focus-visible{outline:3px solid var(--acc-d);outline-offset:3px;border-radius:2px}
.skip{position:absolute;left:16px;top:-60px;background:var(--pri-d);color:#fff;padding:10px 16px;z-index:50;text-decoration:none;border-radius:0 0 6px 6px;transition:top .2s var(--ease)}
.skip:focus{top:0}.skip:hover{color:#fff}

.wrap{max-width:1180px;margin:0 auto;padding:0 24px}.narrow{max-width:640px;text-align:center}
.sec{padding:56px 24px}.art{max-width:820px}.art.wrap{padding-top:40px}
.art p,.art li{max-width:68ch}
.art>.lead{max-width:62ch}

/* thanh đầu trang */
.top{position:sticky;top:0;z-index:20;background:rgba(250,248,245,.92);backdrop-filter:blur(10px);border-bottom:1px solid var(--bd)}
.bar{display:flex;align-items:center;justify-content:space-between;height:68px}
.logo img{height:40px;width:auto}
.menu a{margin-left:28px;text-decoration:none;color:var(--fg);font-size:.92rem;font-weight:500;padding:6px 0;border-bottom:2px solid transparent;transition:color .2s,border-color .2s}
.menu a.on,.menu a:hover{color:var(--pri);border-bottom-color:var(--acc)}
.burger{display:none;background:none;border:0;padding:10px;margin:0 -10px 0 0;color:var(--pri-d);cursor:pointer;line-height:0}
.burger:hover{background:none;filter:none;color:var(--acc-d)}

/* nút, chip */
.btn,button{background:var(--acc);color:#1d1a10;border:0;padding:14px 26px;font:600 .92rem Inter,sans-serif;text-decoration:none;display:inline-flex;align-items:center;gap:10px;cursor:pointer;border-radius:4px;transition:background .2s,transform .2s var(--ease),box-shadow .2s}
.btn:hover,button:hover{background:#d6b977;color:#1d1a10;box-shadow:var(--sh-1)}
.btn:active,button:active{transform:translateY(1px)}
.arr{transition:transform .25s var(--ease);flex:none}
.btn:hover .arr,.more:hover .arr,.feature:hover .more .arr{transform:translateX(4px)}
.more{display:inline-flex;align-items:center;gap:8px;font-weight:600;font-size:.9rem;text-decoration:none}
.chips{display:flex;flex-wrap:wrap;gap:10px;margin:18px 0}
.chip{border:1px solid var(--bd);background:var(--card);color:var(--pri-d);padding:6px 16px;border-radius:999px;font-size:.85rem;text-decoration:none;transition:border-color .2s,background .2s,transform .2s var(--ease)}
.chip:hover{border-color:var(--pri);background:#fff;transform:translateY(-1px)}
.chip.big{border-radius:8px;padding:12px 18px;display:flex;flex-direction:column;min-width:190px}
.chip.big small{color:var(--soft);font-size:.8rem}

/* hero */
.hero{background-size:cover;background-position:center;color:#fff;padding:132px 0 104px}
.hero h1{color:#fff;max-width:780px;font-size:clamp(2.2rem,5vw,3.6rem);margin-bottom:.5em}
.hero p{max-width:560px;font-size:1.12rem;color:rgba(255,255,255,.88);margin:0 0 30px}
.hero .chips{margin-top:34px}
.hero .chip{background:rgba(255,255,255,.1);border-color:rgba(255,255,255,.38);color:#fff;backdrop-filter:blur(4px)}
.hero .chip:hover{background:rgba(255,255,255,.2);border-color:#fff}
@keyframes rise{from{opacity:0;transform:translateY(18px)}to{opacity:1;transform:none}}
.hero .wrap>*{animation:rise .9s var(--ease) both}
.hero .wrap>*:nth-child(2){animation-delay:.08s}.hero .wrap>*:nth-child(3){animation-delay:.16s}.hero .wrap>*:nth-child(4){animation-delay:.24s}

.h-sec{margin-top:0}
.row-h{display:flex;justify-content:space-between;align-items:baseline;gap:16px}
.lead{font-size:1.12rem;color:var(--soft);line-height:1.7}

/* thẻ */
.grid3{display:grid;grid-template-columns:repeat(auto-fill,minmax(290px,1fr));gap:28px;margin-top:22px}
.card{background:var(--card);border:1px solid var(--bd);border-radius:8px;overflow:hidden;box-shadow:var(--sh-1);transition:box-shadow .3s var(--ease),transform .3s var(--ease),border-color .3s}
.card:hover{box-shadow:var(--sh-2);transform:translateY(-3px);border-color:#cfc8b8}
.card a{text-decoration:none;color:inherit;display:block;height:100%}
.ph{overflow:hidden;aspect-ratio:16/9;background:var(--pri-d)}
.ph img{width:100%;height:100%;object-fit:cover;transition:transform .7s var(--ease)}
.card:hover .ph img,.feature:hover .ph img{transform:scale(1.04)}
.pad{padding:22px 24px 24px}
.card h3{margin:.35em 0 .4em;transition:color .2s}.card:hover h3{color:var(--pri)}
.card p{font-size:.92rem;color:var(--soft);margin:.3em 0}
.card.sp{background:linear-gradient(180deg,#f3efe3,var(--card) 90px)}
.latin,.meta,.small{font-size:.82rem;color:var(--soft)}.latin{font-style:italic}
.meta .cat{color:var(--acc-d);font-weight:600;letter-spacing:.02em}
.feature{display:grid;grid-template-columns:1.15fr 1fr;align-items:stretch;text-decoration:none;color:inherit;background:var(--card);border:1px solid var(--bd);border-radius:10px;overflow:hidden;box-shadow:var(--sh-1);transition:box-shadow .3s var(--ease)}
.feature:hover{box-shadow:var(--sh-2)}
.feature .ph{aspect-ratio:auto;min-height:320px}
.fbody{padding:38px 40px;display:flex;flex-direction:column;justify-content:center;gap:2px}
.fbody h3{font-size:clamp(1.4rem,2.4vw,1.8rem);margin:.4em 0 .5em}
.fbody p{color:var(--soft);margin:0 0 18px}

.crumbs{font-size:.82rem;color:var(--soft);margin-bottom:24px}.crumbs i{font-style:normal;margin:0 4px;opacity:.6}
.crumbs a{color:var(--soft)}.crumbs a:hover{color:var(--pri-d)}

/* bài viết */
.cover{margin:26px 0 28px}
.cover img{width:100%;aspect-ratio:16/9;object-fit:cover;border-radius:10px;box-shadow:var(--sh-1)}
.cover figcaption{font-size:.82rem;color:var(--soft);margin-top:10px;max-width:68ch}
.formula{font-size:1.02rem}
.badge{display:inline-block;font-size:.72rem;font-weight:600;padding:2px 10px;border-radius:999px;white-space:nowrap}
.b-manh{background:#d6e6cf;color:#244417}.b-vua{background:#f3e6c4;color:#5f460b}.b-so-bo{background:#ecd9d4;color:#6b2e22}
.legend{list-style:none;padding:0;display:grid;gap:8px}
.tbl{overflow-x:auto;border:1px solid var(--bd);border-radius:8px}
table{border-collapse:collapse;width:100%;background:var(--card)}
th,td{border-bottom:1px solid var(--bd);padding:12px 16px;text-align:left;font-size:.9rem;vertical-align:top}
th{background:var(--mut);font-size:.74rem;text-transform:uppercase;letter-spacing:.08em;color:var(--pri-d)}
tr:last-child td{border-bottom:0}
tbody tr:hover td{background:#faf6ec}
.warn li::marker{color:#b4532a}
.art li{margin:.3em 0}
.spec{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1px;background:var(--bd);border:1px solid var(--bd);border-radius:8px;overflow:hidden;margin:22px 0}
.spec div{background:var(--card);padding:14px 18px}.spec dt{font-size:.7rem;text-transform:uppercase;letter-spacing:.1em;color:var(--soft)}.spec dd{margin:2px 0 0;font-weight:500}
.note{background:var(--mut);padding:16px 20px;border-radius:6px}
details.deep{background:var(--card);border:1px solid var(--bd);border-radius:8px;margin:30px 0;padding:6px 24px}
details.deep summary{cursor:pointer;font-weight:600;padding:14px 0;color:var(--pri-d)}
details.deep[open] summary{border-bottom:1px solid var(--bd);margin-bottom:12px}
.refs{border-top:1px solid var(--bd);margin-top:40px}.refs li{font-size:.85rem;color:var(--soft)}
.disc{background:var(--mut);padding:18px 22px;font-size:.88rem;margin:34px 0;border-radius:6px;max-width:none}
.stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:16px;text-align:center;margin:30px 0}
.stats b{display:block;font:700 2.2rem 'Playfair Display',serif;color:var(--pri);font-variant-numeric:lining-nums}.stats span{font-size:.85rem;color:var(--soft)}

/* bản tin, form */
.news{background:var(--pri);color:#fff;padding:76px 0;margin-top:48px}.news h2{color:#fff;margin-top:0}.news p{color:rgba(255,255,255,.82)}
.inline{display:flex;max-width:480px;margin:22px auto 0;gap:0}
.inline input{flex:1;min-width:0;padding:14px 18px;border:1px solid rgba(255,255,255,.35);border-right:0;background:rgba(255,255,255,.1);color:#fff;font:inherit;border-radius:4px 0 0 4px}
.inline button{border-radius:0 4px 4px 0;white-space:nowrap}
.inline input::placeholder{color:rgba(255,255,255,.82)}
.inline input:focus-visible{outline-color:var(--acc);outline-offset:0}
.stack{display:grid;gap:16px;max-width:560px}.stack label{display:grid;gap:6px;font-weight:500;font-size:.9rem}
.stack input,.stack select,.stack textarea{padding:12px 14px;border:1px solid var(--bd);font:inherit;background:var(--card);border-radius:4px;transition:border-color .2s,box-shadow .2s}
.stack input:focus,.stack select:focus,.stack textarea:focus{border-color:var(--pri);box-shadow:0 0 0 3px rgba(75,92,57,.18);outline:0}
.filter{width:100%;max-width:520px;padding:12px 16px;border:1px solid var(--bd);font:inherit;background:var(--card);margin:8px 0 18px;border-radius:4px;transition:border-color .2s,box-shadow .2s}
.filter:focus{border-color:var(--pri);box-shadow:0 0 0 3px rgba(75,92,57,.18);outline:0}

/* chân trang */
.foot{background:var(--pri-d);color:rgba(255,255,255,.82);padding:60px 0 24px;font-size:.88rem}
.foot img{height:36px;width:auto}
.grid4{display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:36px}
.foot h3{color:#fff;font:600 .72rem Inter,sans-serif;margin:0 0 .8em;letter-spacing:.14em;text-transform:uppercase}
.foot a{display:block;color:inherit;text-decoration:none;margin:7px 0}.foot a:hover{color:#fff;text-decoration:underline}
.legal{border-top:1px solid rgba(255,255,255,.18);margin-top:36px;padding-top:18px;font-size:.78rem;color:rgba(255,255,255,.7)}

@media(max-width:820px){
  .burger{display:block}
  .menu{display:none;position:absolute;top:68px;left:0;right:0;background:var(--bg);padding:8px 24px 14px;border-bottom:1px solid var(--bd);box-shadow:var(--sh-2)}
  .menu.open{display:block}.menu a{display:block;margin:0;padding:12px 0;border-bottom:1px solid var(--bd)}
  .menu a:last-child{border-bottom:0}
  .feature{grid-template-columns:1fr}.feature .ph{aspect-ratio:16/9;min-height:0}.fbody{padding:26px 24px}
  .grid4{grid-template-columns:1fr 1fr}.hero{padding:84px 0 64px}
  .sec{padding:40px 20px}.wrap{padding:0 20px}
}
@media(max-width:520px){
  .grid4{grid-template-columns:1fr}
  .row-h{flex-direction:column;align-items:flex-start;gap:4px}
  .inline{flex-direction:column;gap:10px}
  .inline input{border-right:1px solid rgba(255,255,255,.35);border-radius:4px}.inline button{border-radius:4px;justify-content:center}
}
@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}
}