/* ===========================================================
   LAYER 7 STUDIO — shared design system (site.css)
   Dùng chung cho work.html, about.html, insights.html.
   index.html hiện vẫn giữ CSS inline (bản gốc) — khi nào gọn lại sẽ trỏ về file này.
   =========================================================== */
:root{
  --bg:#171426; --bg-2:#1E1B30; --bg-3:#252138; --bg-elev:#333340;
  --fg:#F4F2F7; --muted:#8E8AA0; --muted-2:#4A4660;
  --accent:#FF5945; --accent-2:#9100FF; --accent-3:#9B51E0; --accent-4:#FFD166;
  --border:#333340;
  --display:'Space Grotesk',sans-serif; --mono:'JetBrains Mono',monospace;
  --maxw:1280px; --gut:max(40px, calc((100% - var(--maxw)) / 2));
  --ease:cubic-bezier(.16,1,.3,1);
}
*{margin:0;padding:0;box-sizing:border-box}
html{scroll-behavior:smooth}
body{background:var(--bg);color:var(--fg);font-family:var(--display);overflow-x:hidden;line-height:1.5;-webkit-font-smoothing:antialiased}
img{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
::selection{background:var(--accent);color:#0d0a18}
body::after{content:'';position:fixed;inset:0;z-index:9000;pointer-events:none;opacity:.5;background:repeating-linear-gradient(0deg, rgba(0,0,0,.16) 0 1px, transparent 1px 3px);mix-blend-mode:overlay}

/* ---- CURSOR ---- */
.cur,.cur-ring{position:fixed;top:0;left:0;z-index:9500;pointer-events:none;border-radius:50%;transform:translate(-50%,-50%)}
.cur{width:6px;height:6px;background:var(--accent)}
.cur-ring{width:30px;height:30px;border:1px solid rgba(255,89,69,.6);transition:width .2s,height .2s,background .2s,border-color .2s}
.cur-ring.lg{width:54px;height:54px;background:rgba(255,89,69,.08);border-color:var(--accent)}
body.hascursor{cursor:none}
body.hascursor a,body.hascursor button{cursor:none}
@media (hover:none){.cur,.cur-ring{display:none!important}}

/* ---- HUD CORNERS ---- */
.hud-corner{position:fixed;width:26px;height:26px;z-index:400;pointer-events:none;opacity:.35}
.hud-corner::before,.hud-corner::after{content:'';position:absolute;background:var(--accent)}
.hud-corner::before{width:100%;height:1px}.hud-corner::after{width:1px;height:100%}
.hud-tl{top:18px;left:18px}.hud-tl::before{top:0;left:0}.hud-tl::after{top:0;left:0}
.hud-tr{top:18px;right:18px}.hud-tr::before{top:0;right:0}.hud-tr::after{top:0;right:0}
.hud-bl{bottom:18px;left:18px}.hud-bl::before{bottom:0;left:0}.hud-bl::after{bottom:0;left:0}
.hud-br{bottom:18px;right:18px}.hud-br::before{bottom:0;right:0}.hud-br::after{bottom:0;right:0}
@media(max-width:700px){.hud-corner{display:none}}

/* ---- SCROLL RAIL ---- */
.rail{position:fixed;left:30px;top:50%;transform:translateY(-50%);z-index:410;display:flex;align-items:center;gap:14px}
.rail-track{position:relative;width:2px;height:190px;background:var(--border)}
.rail-fill{position:absolute;left:0;bottom:0;width:100%;background:var(--accent);box-shadow:0 0 10px rgba(255,89,69,.8);height:0;transition:height .12s linear}
.rail-tick{position:absolute;left:-4px;width:10px;height:1px;background:var(--muted-2);transition:background .2s}
.rail-tick.on{background:var(--accent)}
.rail-dot{position:absolute;left:50%;bottom:0;transform:translate(-50%,50%);width:9px;height:9px;border-radius:50%;background:var(--accent);box-shadow:0 0 14px rgba(255,89,69,.9);transition:bottom .12s linear}
.rail-meta{display:flex;flex-direction:column;font-family:var(--mono);text-transform:uppercase;line-height:1.3}
.rail-meta .ly{font-size:14px;font-weight:700;color:var(--accent);letter-spacing:1px}
.rail-meta .nm{font-size:9px;letter-spacing:2px;color:var(--muted);margin-top:2px}
.rail-meta .pc{font-size:9px;letter-spacing:1px;color:var(--muted-2);margin-top:8px}
@media(max-width:1100px){.rail{display:none}}

/* ---- REVEAL ---- */
[data-reveal]{opacity:0;transform:translateY(28px);transition:opacity .7s var(--ease),transform .7s var(--ease)}
[data-reveal].in{opacity:1;transform:none}
[data-reveal][data-d="1"]{transition-delay:.08s}[data-reveal][data-d="2"]{transition-delay:.16s}
[data-reveal][data-d="3"]{transition-delay:.24s}[data-reveal][data-d="4"]{transition-delay:.32s}
[data-reveal][data-d="5"]{transition-delay:.40s}[data-reveal][data-d="6"]{transition-delay:.48s}

/* ---- SHARED TYPE ---- */
.eyebrow{font-family:var(--mono);font-size:11px;letter-spacing:3px;text-transform:uppercase;color:var(--accent);display:flex;align-items:center;gap:10px;margin-bottom:20px}
.eyebrow::before{content:'';width:22px;height:1px;background:var(--accent)}
.title{font-weight:700;font-size:clamp(32px,4.4vw,58px);line-height:1.02;letter-spacing:-.02em}
.sub{color:var(--muted);font-size:16px;max-width:52ch;margin-top:18px;line-height:1.6}
.accent{color:var(--accent)}.pink{color:var(--accent)}
.btn{display:inline-flex;align-items:center;gap:10px;font-family:var(--mono);font-weight:700;font-size:13px;letter-spacing:1px;text-transform:uppercase;padding:16px 26px;border:1px solid var(--border);transition:.25s var(--ease);position:relative}
.btn-primary{background:var(--accent);color:#160a08;border-color:var(--accent)}
.btn-primary:hover{box-shadow:0 0 32px rgba(255,89,69,.45);transform:translateY(-2px)}
.btn-secondary:hover{border-color:var(--accent);color:var(--accent)}

/* ---- NAV ---- */
.nav{position:fixed;top:0;left:0;right:0;z-index:500;display:flex;align-items:center;justify-content:space-between;padding:20px var(--gut);transition:background .3s,backdrop-filter .3s,border-color .3s;border-bottom:1px solid transparent}
.nav.scrolled{background:rgba(23,20,38,.82);backdrop-filter:blur(14px);border-bottom-color:var(--border)}
.nav-brand{display:flex;align-items:center;gap:11px;font-weight:700;letter-spacing:1px;font-size:15px}
.nav-logo{height:24px;width:auto;display:block}
.nav-stack{display:flex;flex-direction:column;gap:2px}
.nav-stack span{height:2px;background:var(--muted);display:block}
.nav-stack span:nth-child(1){width:8px}.nav-stack span:nth-child(2){width:12px}.nav-stack span:nth-child(3){width:16px;background:var(--accent)}
.nav-links{display:flex;gap:30px;font-family:var(--mono);font-size:12px;letter-spacing:1px;text-transform:uppercase}
.nav-links a{color:var(--muted);transition:color .2s;position:relative}
.nav-links a:hover,.nav-links a.current{color:var(--fg)}
.nav-links a::after{content:'';position:absolute;left:0;bottom:-5px;width:0;height:1px;background:var(--accent);transition:width .25s var(--ease)}
.nav-links a:hover::after,.nav-links a.current::after{width:100%}
.nav-cta{font-family:var(--mono);font-size:12px;letter-spacing:1px;text-transform:uppercase;border:1px solid var(--border);padding:10px 18px;transition:.25s}
.nav-cta:hover{border-color:var(--accent);color:var(--accent)}
.nav-toggle{display:none;background:none;border:1px solid var(--border);width:40px;height:40px;cursor:pointer;position:relative;flex:none;padding:0}
.nav-toggle span{position:absolute;left:9px;right:9px;height:2px;background:var(--fg);top:50%;margin-top:-1px;transition:transform .25s var(--ease),opacity .2s}
.nav-toggle span:nth-child(1){transform:translateY(-6px)}
.nav-toggle span:nth-child(3){transform:translateY(6px)}
.nav.open .nav-toggle span:nth-child(1){transform:rotate(45deg)}
.nav.open .nav-toggle span:nth-child(2){opacity:0}
.nav.open .nav-toggle span:nth-child(3){transform:rotate(-45deg)}
@media(max-width:900px){
  .nav-toggle{display:block}
  .nav-cta{padding:9px 13px;font-size:11px}
  .nav-links{display:flex;flex-direction:column;gap:0;position:absolute;top:100%;left:0;right:0;background:rgba(23,20,38,.97);backdrop-filter:blur(14px);border-bottom:1px solid var(--border);padding:0 var(--gut);max-height:0;overflow:hidden;transition:max-height .3s var(--ease)}
  .nav.open .nav-links{max-height:70vh;padding:8px var(--gut) 16px}
  .nav-links a{padding:15px 0;font-size:13px;border-bottom:1px solid var(--border)}
  .nav-links a:last-child{border-bottom:none}
}

/* ---- SECTION ---- */
.section{padding:120px var(--gut);position:relative;border-top:1px solid var(--border)}
.section-head{max-width:680px;margin-bottom:64px}
.hero-meta-dot{width:6px;height:6px;background:var(--accent);border-radius:50%;display:inline-block}

/* ---- SUB-PAGE HERO ---- */
.page-hero{padding:170px var(--gut) 90px;position:relative;overflow:hidden}
.page-hero .title{font-size:clamp(40px,6.5vw,88px);line-height:.98}
.page-hero .sub{font-size:18px;max-width:60ch;margin-top:24px}
.page-hero-grid{position:absolute;inset:-60px;z-index:0;background-image:linear-gradient(rgba(255,89,69,.05) 1px,transparent 1px),linear-gradient(90deg,rgba(255,89,69,.05) 1px,transparent 1px);background-size:54px 54px;-webkit-mask-image:radial-gradient(ellipse 70% 80% at 70% 30%,#000,transparent 75%);mask-image:radial-gradient(ellipse 70% 80% at 70% 30%,#000,transparent 75%)}
.page-hero>*{position:relative;z-index:1}
/* ambient signal waves (đặt .page-hero .hero-waves để thắng .page-hero>* về specificity) */
.page-hero .hero-waves{position:absolute;inset:0;z-index:0;overflow:hidden;pointer-events:none;
  -webkit-mask:radial-gradient(ellipse 78% 92% at 76% 58%,#000 8%,transparent 76%);
  mask:radial-gradient(ellipse 78% 92% at 76% 58%,#000 8%,transparent 76%)}
.hero-waves svg{position:absolute;inset:0;width:100%;height:100%;display:block}
.hero-waves .hw{fill:none;stroke-width:1.3;vector-effect:non-scaling-stroke;animation-name:hwDrift;animation-timing-function:linear;animation-iteration-count:infinite}
@keyframes hwDrift{to{transform:translateX(-360px)}}
.breadcrumb{font-family:var(--mono);font-size:11px;letter-spacing:2px;text-transform:uppercase;color:var(--muted);margin-bottom:26px;display:flex;gap:9px;align-items:center}
.breadcrumb a:hover{color:var(--accent)}
.breadcrumb .sep{color:var(--muted-2)}

/* ---- WORK CARDS (shared homepage + work page) ---- */
.work-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}
.card{position:relative;aspect-ratio:16/9;overflow:hidden;background:var(--bg-2);border:1px solid var(--border);transform-style:preserve-3d;transition:border-color .3s,box-shadow .3s}
.card:hover{border-color:var(--accent);box-shadow:0 18px 50px rgba(0,0,0,.5),0 0 30px rgba(255,89,69,.18)}
.card-img{width:100%;height:100%;object-fit:cover;transition:transform .5s var(--ease),filter .4s;filter:saturate(.92)}
.card:hover .card-img{transform:scale(1.07);filter:saturate(1.12)}
.card::after{content:'';position:absolute;left:0;right:0;top:0;height:42%;background:linear-gradient(180deg,rgba(255,89,69,.22),transparent);opacity:0;transform:translateY(-100%);transition:opacity .3s}
.card:hover::after{opacity:1;animation:scan 1.6s linear infinite}
@keyframes scan{0%{transform:translateY(-100%)}100%{transform:translateY(340%)}}
.card-tag{position:absolute;top:14px;left:14px;z-index:3;font-family:var(--mono);font-size:9px;letter-spacing:1.5px;text-transform:uppercase;background:var(--accent);color:#160a08;padding:5px 9px;font-weight:700}
.card-tag.alt{background:var(--bg);color:var(--accent);border:1px solid var(--accent)}
.card-reticle{position:absolute;top:14px;right:14px;z-index:3;width:26px;height:26px;opacity:0;transition:opacity .3s}
.card-reticle::before,.card-reticle::after{content:'';position:absolute;background:var(--accent)}
.card-reticle::before{top:50%;left:0;right:0;height:1px}.card-reticle::after{left:50%;top:0;bottom:0;width:1px}
.card:hover .card-reticle{opacity:.9}
.card-ov{position:absolute;left:0;right:0;bottom:0;z-index:3;padding:20px;background:linear-gradient(180deg,transparent,rgba(13,10,24,.94));transform:translateY(8px);opacity:.92;transition:transform .35s var(--ease),opacity .35s}
.card:hover .card-ov{transform:none;opacity:1}
.card-genre{font-family:var(--mono);font-size:10px;letter-spacing:1.5px;text-transform:uppercase;color:var(--accent);margin-bottom:7px}
.card-title{font-size:19px;font-weight:600;margin-bottom:5px}
.card-meta{font-family:var(--mono);font-size:11px;color:var(--muted);max-height:0;overflow:hidden;opacity:0;transition:max-height .35s var(--ease),opacity .35s}
.card:hover .card-meta{max-height:40px;opacity:1}
.card.hide{display:none}
@media(max-width:900px){.work-grid{grid-template-columns:1fr 1fr;gap:12px}}
@media(max-width:560px){.work-grid{grid-template-columns:1fr}}

/* ---- FILTER CHIPS ---- */
.filters{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:40px}
.chip{font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted);border:1px solid var(--border);padding:9px 16px;cursor:pointer;transition:.2s;background:none}
.chip:hover{color:var(--fg);border-color:var(--muted)}
.chip.active{background:var(--accent);color:#160a08;border-color:var(--accent)}

/* ---- INSIGHTS ---- */
.posts{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--border);border:1px solid var(--border)}
.post{background:var(--bg);padding:34px 30px;display:flex;flex-direction:column;gap:13px;transition:background .3s;min-height:280px}
.post:hover{background:var(--bg-2)}
.post-cat{font-family:var(--mono);font-size:10px;letter-spacing:1.6px;text-transform:uppercase;color:var(--accent)}
.post h3{font-size:21px;font-weight:600;line-height:1.25}
.post p{color:var(--muted);font-size:14px;line-height:1.55}
.post-foot{margin-top:auto;font-family:var(--mono);font-size:10px;letter-spacing:1px;text-transform:uppercase;color:var(--muted-2);display:flex;justify-content:space-between;gap:10px}
.post.soon{opacity:.5}
.post.feature{grid-column:1 / -1;flex-direction:row;align-items:center;gap:44px;padding:48px 40px;background:var(--bg-2)}
.post.feature .post-body{flex:1}
.post.feature h3{font-size:clamp(24px,3vw,38px);margin:12px 0 14px;line-height:1.1}
.post.feature .post-art{width:320px;height:210px;flex:none;background:radial-gradient(circle at 30% 30%,rgba(255,89,69,.18),transparent 60%),linear-gradient(135deg,var(--bg-3),var(--bg));border:1px solid var(--border);display:grid;place-items:center;font-family:var(--mono);font-size:11px;letter-spacing:2px;text-transform:uppercase;color:var(--muted)}
@media(max-width:900px){.posts{grid-template-columns:1fr}.post.feature{flex-direction:column;align-items:flex-start;gap:24px}.post.feature .post-art{width:100%}}

/* ---- ABOUT ---- */
.prose{max-width:72ch}
.prose p{color:var(--muted);font-size:17px;line-height:1.75;margin-bottom:22px}
.prose p b,.prose p strong{color:var(--fg);font-weight:600}
.prose .accent{color:var(--accent)}
.values{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--border);border:1px solid var(--border)}
.value{background:var(--bg);padding:34px 28px;transition:background .3s}
.value:hover{background:var(--bg-2)}
.value .vn{font-family:var(--mono);font-size:12px;color:var(--accent);margin-bottom:16px}
.value h3{font-size:19px;font-weight:600;margin-bottom:10px}
.value p{color:var(--muted);font-size:14px;line-height:1.55}
.factgrid{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--border);border:1px solid var(--border)}
.fact{background:var(--bg);padding:34px 26px}
.fact b{display:block;font-weight:700;font-size:clamp(32px,4vw,52px);color:var(--accent);line-height:1;letter-spacing:-.02em}
.fact span{font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted);margin-top:12px;display:block}
@media(max-width:900px){.values{grid-template-columns:1fr}.factgrid{grid-template-columns:1fr 1fr}}

/* ---- FOUNDER card (shared) ---- */
.fcard{background:var(--bg-2);border:1px solid var(--border);padding:40px;display:flex;gap:26px;align-items:flex-start}
.favatar{width:84px;height:84px;flex:none;background:linear-gradient(135deg,var(--accent),var(--accent-2));display:flex;align-items:center;justify-content:center;font-weight:700;font-size:34px;color:#fff}
.fquote{font-size:20px;line-height:1.5;font-weight:500}
.fbyline{font-family:var(--mono);font-size:11px;letter-spacing:1px;color:var(--muted);margin-top:20px;line-height:1.8;text-transform:uppercase}
.fbyline strong{color:var(--fg)}
@media(max-width:900px){.fcard{flex-direction:column}}

/* ---- OSI MODEL (signature, shared) ---- */
.osi-grid{display:grid;grid-template-columns:minmax(300px,440px) 1fr;gap:clamp(2.5rem,5vw,6rem);align-items:center}
.osi{display:flex;flex-direction:column;gap:10px}
.osi-layer{display:flex;align-items:center;gap:16px;opacity:0;transform:translateX(-30px)}
.osi-layer .lbl{font-family:var(--mono);font-size:11px;letter-spacing:1.2px;text-transform:uppercase;color:var(--muted);width:130px;text-align:right;flex:none}
.osi-layer .bar{height:26px;background:var(--bg-3);border:1px solid var(--border);flex:1;transition:.3s}
.osi-layer.l7 .bar{background:var(--accent);border-color:var(--accent);box-shadow:0 0 44px rgba(255,89,69,.45)}
.osi-layer.l7 .lbl{color:var(--accent);font-weight:700}
.osi.in .osi-layer{animation:osiSlide .6s var(--ease) forwards}
@keyframes osiSlide{to{opacity:1;transform:translateX(0)}}
.osi.in .osi-layer:nth-child(1){animation-delay:.05s}.osi.in .osi-layer:nth-child(2){animation-delay:.14s}
.osi.in .osi-layer:nth-child(3){animation-delay:.23s}.osi.in .osi-layer:nth-child(4){animation-delay:.32s}
.osi.in .osi-layer:nth-child(5){animation-delay:.41s}.osi.in .osi-layer:nth-child(6){animation-delay:.50s}
.osi.in .osi-layer:nth-child(7){animation-delay:.70s}
.osi-lead{color:var(--muted);margin-top:22px;max-width:560px;font-size:16px;line-height:1.6}
.osi-lead b{color:var(--fg);font-weight:600}
@media(max-width:960px){.osi-grid{grid-template-columns:1fr}.osi-layer .lbl{width:96px;font-size:9px}}

/* ---- CTA strip (sub-pages) ---- */
.cta-strip{text-align:center;padding:120px var(--gut);border-top:1px solid var(--border);background:linear-gradient(180deg,var(--bg) 0%,#0E0B17 100%)}
.cta-strip .title{font-size:clamp(32px,5vw,64px)}
.cta-strip .sub{margin:18px auto 36px;max-width:52ch}
.cta-strip .btn-primary{font-size:14px;padding:18px 30px}

/* ---- FOOTER ---- */
footer{padding:80px var(--gut) 36px;border-top:1px solid var(--border);background:var(--bg)}
.footer-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:40px}
.footer-brand{font-weight:700;font-size:22px;letter-spacing:1px}
.footer-logo{height:30px;width:auto;display:block;margin-bottom:14px}
.footer-tagline{color:var(--muted);font-size:14px;line-height:1.6}
.footer-tagline strong{color:var(--fg)}
.footer-col h4{font-family:var(--mono);font-size:11px;letter-spacing:2px;text-transform:uppercase;color:var(--muted);margin-bottom:18px}
.footer-col a{display:block;color:var(--fg);font-size:14px;padding:6px 0;transition:color .2s}
.footer-col a:hover{color:var(--accent)}
.footer-bottom{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:16px;margin-top:60px;padding-top:28px;border-top:1px solid var(--border);font-family:var(--mono);font-size:11px;letter-spacing:1px;color:var(--muted)}
.footer-osi{display:flex;gap:16px;flex-wrap:wrap}
.footer-osi .active{color:var(--accent)}
@media(max-width:900px){.footer-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.footer-grid{grid-template-columns:1fr}}

/* ---- SERVICES PAGE ---- */
.srv{border-top:1px solid var(--border);padding:44px 0;display:grid;grid-template-columns:60px 1fr 170px;gap:30px;align-items:start}
.srv:last-of-type{border-bottom:1px solid var(--border)}
.srv-no{font-family:var(--mono);font-size:13px;color:var(--accent)}
.srv h3{font-size:clamp(22px,2.6vw,30px);font-weight:600;margin-bottom:12px}
.srv p{color:var(--muted);font-size:15px;line-height:1.6;max-width:62ch}
.srv .svc-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:18px}
.srv .svc-tags span{font-family:var(--mono);font-size:10px;letter-spacing:1px;text-transform:uppercase;color:var(--muted);border:1px solid var(--border);padding:5px 10px}
.srv-price{font-family:var(--mono);font-size:14px;color:var(--fg);text-align:right;font-weight:700}
.srv-price span{display:block;color:var(--muted);font-size:10px;letter-spacing:1px;text-transform:uppercase;margin-top:5px;font-weight:400}
@media(max-width:760px){.srv{grid-template-columns:1fr;gap:14px}.srv-price{text-align:left}}

/* ---- PRICING ---- */
.price{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--border);border:1px solid var(--border)}
.price .p{background:var(--bg);padding:36px 30px;display:flex;flex-direction:column}
.price .p.feat{background:var(--bg-2);border-top:2px solid var(--accent)}
.price .nm{font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted)}
.price .amt{font-family:var(--display);font-weight:700;font-size:30px;margin:12px 0 4px;letter-spacing:-.02em}
.price .p.feat .amt{color:var(--accent)}
.price .pd{color:var(--muted);font-size:14px;line-height:1.55;margin-bottom:20px}
.price ul{list-style:none;display:flex;flex-direction:column;gap:9px;margin-bottom:24px}
.price li{font-size:13.5px;color:var(--muted);padding-left:18px;position:relative}
.price li::before{content:'+';position:absolute;left:0;color:var(--accent);font-family:var(--mono)}
.price .pbtn{margin-top:auto;text-align:center;font-family:var(--mono);font-size:12px;letter-spacing:1px;text-transform:uppercase;border:1px solid var(--border);padding:13px;transition:.2s}
.price .p.feat .pbtn{background:var(--accent);color:#160a08;border-color:var(--accent)}
.price .pbtn:hover{border-color:var(--accent);color:var(--accent)}
.price .p.feat .pbtn:hover{color:#160a08;box-shadow:0 0 24px rgba(255,89,69,.4)}
@media(max-width:860px){.price{grid-template-columns:1fr}}
.retainer{margin-top:24px;font-family:var(--mono);font-size:13px;color:var(--muted)}
.retainer b{color:var(--accent)}

/* ---- CASE STUDY ---- */
.cs-hero{padding:160px var(--gut) 0}
.cs-meta{display:flex;flex-wrap:wrap;gap:14px 40px;margin-top:30px;font-family:var(--mono);font-size:11px;letter-spacing:1px;text-transform:uppercase;color:var(--muted)}
.cs-meta b{color:var(--fg);display:block;margin-top:4px;font-weight:600}
.cs-cover{margin-top:50px;border:1px solid var(--border);overflow:hidden;aspect-ratio:16/9;background:var(--bg-2)}
.cs-cover img{width:100%;height:100%;object-fit:cover}
.cs-body{padding:80px clamp(24px,5vw,40px);max-width:864px;margin:0 auto}
.cs-body h2{font-size:clamp(24px,3vw,34px);font-weight:700;margin:48px 0 18px;letter-spacing:-.01em}
.cs-body h2:first-child{margin-top:0}
.cs-body p{color:var(--muted);font-size:17px;line-height:1.75;margin-bottom:20px}
.cs-body p b{color:var(--fg);font-weight:600}
.cs-fig{margin:36px 0;border:1px solid var(--border);overflow:hidden;background:var(--bg-2)}
.cs-fig img{width:100%;display:block}
.cs-fig figcaption{font-family:var(--mono);font-size:11px;color:var(--muted);padding:12px 16px;border-top:1px solid var(--border)}
.cs-metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--border);border:1px solid var(--border);margin:40px 0}
.cs-metric{background:var(--bg);padding:26px 22px}
.cs-metric b{display:block;font-weight:700;font-size:22px;color:var(--accent);margin-bottom:8px}
.cs-metric span{font-family:var(--mono);font-size:11px;letter-spacing:.5px;text-transform:uppercase;color:var(--muted);line-height:1.5;display:block}
.cs-next{border-top:1px solid var(--border);padding:50px var(--gut);display:flex;justify-content:space-between;align-items:center;gap:20px;flex-wrap:wrap;font-family:var(--mono);font-size:12px;letter-spacing:1px;text-transform:uppercase}
.cs-next a:hover{color:var(--accent)}
@media(max-width:700px){.cs-metrics{grid-template-columns:1fr}}

/* ---- ARTICLE ---- */
.article{padding:150px var(--gut) 0}
.article-head{max-width:740px;margin:0 auto}
.article-head h1{font-size:clamp(30px,4.5vw,52px);font-weight:700;line-height:1.08;letter-spacing:-.02em;margin:18px 0}
.article-byline{display:flex;flex-wrap:wrap;gap:8px 18px;font-family:var(--mono);font-size:11px;letter-spacing:1px;text-transform:uppercase;color:var(--muted)}
.article-byline .accent{color:var(--accent)}
.article-body{max-width:700px;margin:0 auto;padding:46px clamp(24px,5vw,40px) 0}
.article-body p{color:var(--muted);font-size:17px;line-height:1.8;margin-bottom:22px}
.article-body h2{font-size:25px;font-weight:700;margin:42px 0 16px;color:var(--fg)}
.article-body b,.article-body strong{color:var(--fg);font-weight:600}
.article-body ul{margin:0 0 22px 0;padding-left:22px;color:var(--muted);font-size:17px;line-height:1.8}
.article-body li{margin-bottom:8px}
.pullquote{border-left:2px solid var(--accent);padding:6px 0 6px 24px;margin:34px 0;font-size:22px;line-height:1.4;color:var(--fg);font-weight:500}
.article-foot{max-width:700px;margin:54px auto 0;padding:30px clamp(24px,5vw,40px);border-top:1px solid var(--border);display:flex;gap:18px;align-items:center}

/* ---- CONTACT ---- */
.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:54px;align-items:start}
.contact-methods{display:flex;flex-direction:column;gap:1px;background:var(--border);border:1px solid var(--border)}
.cmethod{background:var(--bg);padding:22px 26px;display:flex;justify-content:space-between;align-items:center;gap:16px;transition:background .3s}
.cmethod:hover{background:var(--bg-2)}
.cmethod .cm-l{font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted)}
.cmethod .cm-v{font-size:15px;font-weight:500}
.cmethod .cm-v.accent{color:var(--accent)}
.form-wrap{max-width:640px;margin:0 auto}
.form{display:flex;flex-direction:column;gap:18px}
.field label{display:block;font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted);margin-bottom:8px}
.field input,.field textarea,.field select{width:100%;background:var(--bg-2);border:1px solid var(--border);color:var(--fg);font-family:var(--display);font-size:15px;padding:14px 16px;transition:border-color .2s}
.field input:focus,.field textarea:focus,.field select:focus{outline:none;border-color:var(--accent)}
.field textarea{min-height:130px;resize:vertical}
.field input[type=file]{padding:11px 14px;font-family:var(--mono);font-size:12px;color:var(--muted);cursor:pointer}
.field input[type=file]::file-selector-button{font-family:var(--mono);font-size:11px;letter-spacing:1px;text-transform:uppercase;background:var(--bg-3);color:var(--fg);border:1px solid var(--border);padding:9px 14px;margin-right:14px;cursor:pointer;transition:.2s}
.field input[type=file]::file-selector-button:hover{border-color:var(--accent);color:var(--accent)}
.field-hint{font-family:var(--mono);font-size:10px;letter-spacing:.5px;color:var(--muted-2);margin-top:8px}
.form .btn{margin-top:6px;align-self:flex-start;cursor:pointer}
.next-steps{display:flex;flex-direction:column;gap:1px;background:var(--border);border:1px solid var(--border);margin-top:50px}
.next-step{background:var(--bg);padding:22px 26px;display:flex;gap:18px;align-items:flex-start}
.next-step .ns-n{font-family:var(--mono);font-size:13px;color:var(--accent);flex:none}
.next-step h4{font-size:16px;font-weight:600;margin-bottom:5px}
.next-step p{color:var(--muted);font-size:14px;line-height:1.5}
@media(max-width:860px){.contact-grid{grid-template-columns:1fr;gap:40px}}

@media(prefers-reduced-motion:reduce){
  *{animation-duration:.001s!important;transition-duration:.001s!important}
  [data-reveal]{opacity:1;transform:none}
  .card:hover::after{animation:none}
}

/* ===========================================================
   HOMEPAGE-ONLY (gộp từ index.html inline — selector không dùng ở trang con)
   =========================================================== */
/* PRELOADER */
.preload{position:fixed;inset:0;z-index:9800;background:var(--bg);display:flex;flex-direction:column;align-items:center;justify-content:center;gap:22px;transition:opacity .6s ease,visibility .6s}
.preload.done{opacity:0;visibility:hidden}
.pl-stack{display:flex;flex-direction:column;gap:5px;width:160px}
.pl-stack i{height:9px;background:var(--bg-3);border:1px solid var(--border);transform:scaleX(0);transform-origin:left;animation:plBar .5s var(--ease) forwards}
.pl-stack i:nth-child(1){width:42%;animation-delay:.05s}.pl-stack i:nth-child(2){width:54%;animation-delay:.13s}
.pl-stack i:nth-child(3){width:64%;animation-delay:.21s}.pl-stack i:nth-child(4){width:74%;animation-delay:.29s}
.pl-stack i:nth-child(5){width:84%;animation-delay:.37s}.pl-stack i:nth-child(6){width:92%;animation-delay:.45s}
.pl-stack i:nth-child(7){width:100%;background:var(--accent);border-color:var(--accent);box-shadow:0 0 20px rgba(255,89,69,.6);animation-delay:.55s}
@keyframes plBar{to{transform:scaleX(1)}}
.pl-text{font-family:var(--mono);font-size:11px;letter-spacing:3px;text-transform:uppercase;color:var(--muted)}
.pl-text b{color:var(--accent)}
/* HERO */
.hero{position:relative;min-height:100vh;display:flex;flex-direction:column;justify-content:center;padding:140px var(--gut) 80px;overflow:hidden}
.hero-bg{position:absolute;inset:0;z-index:0}
.hero-img{width:100%;height:100%;object-fit:cover;opacity:.20;filter:saturate(1.1)}
.hero-scrim{position:absolute;inset:0;background:radial-gradient(ellipse 90% 70% at 30% 40%,transparent,var(--bg) 78%),linear-gradient(180deg,var(--bg) 0%,transparent 30%,transparent 60%,var(--bg) 100%)}
.hero-grid{position:absolute;inset:-60px;z-index:0;background-image:linear-gradient(rgba(255,89,69,.06) 1px,transparent 1px),linear-gradient(90deg,rgba(255,89,69,.06) 1px,transparent 1px);background-size:54px 54px;-webkit-mask-image:radial-gradient(ellipse 60% 60% at 35% 45%,#000,transparent 75%);mask-image:radial-gradient(ellipse 60% 60% at 35% 45%,#000,transparent 75%);transition:transform .2s ease-out}
.hero-content{position:relative;z-index:2;max-width:920px}
.hero-eyebrow{font-family:var(--mono);font-size:12px;letter-spacing:3px;text-transform:uppercase;color:var(--muted);margin-bottom:26px;display:flex;align-items:center;gap:10px}
.hero-eyebrow::before{content:'';width:8px;height:8px;background:var(--accent);border-radius:50%;box-shadow:0 0 12px var(--accent);animation:pulse 2s infinite}
@keyframes pulse{0%,100%{opacity:1}50%{opacity:.35}}
.hero-title{font-weight:700;font-size:clamp(44px,8.5vw,118px);line-height:.94;letter-spacing:-.03em}
.hero-title .ln{display:block;overflow:hidden}
.hero-title .ln span{display:block;transform:translateY(110%);animation:lineUp .9s var(--ease) forwards}
.hero-title .ln:nth-child(1) span{animation-delay:.1s}.hero-title .ln:nth-child(2) span{animation-delay:.22s}.hero-title .ln:nth-child(3) span{animation-delay:.34s}
@keyframes lineUp{to{transform:translateY(0)}}
.hero-sub{color:var(--muted);font-size:18px;max-width:56ch;margin-top:30px;line-height:1.65;opacity:0;animation:fadeUp .8s var(--ease) .6s forwards}
.hero-cta-row{display:flex;gap:16px;margin-top:40px;flex-wrap:wrap;opacity:0;animation:fadeUp .8s var(--ease) .75s forwards}
@keyframes fadeUp{from{opacity:0;transform:translateY(20px)}to{opacity:1;transform:none}}
.hero-meta{position:relative;z-index:2;display:flex;flex-wrap:wrap;gap:14px 40px;margin-top:auto;padding-top:60px;font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted);opacity:0;animation:fadeUp .8s var(--ease) .9s forwards}
.hero-meta-item{display:flex;align-items:center;gap:8px}
/* STATS */
.stats{display:grid;grid-template-columns:repeat(4,1fr);padding-left:var(--gut);padding-right:var(--gut);border-top:1px solid var(--border);border-bottom:1px solid var(--border);background:var(--bg-2)}
.stat{padding:50px 30px;border-right:1px solid var(--border)}
.stat:first-child{padding-left:0}
.stat:last-child{padding-right:0;border-right:none}
.stat-num{font-weight:700;font-size:clamp(44px,5vw,68px);color:var(--accent);line-height:1;letter-spacing:-.02em}
.stat-label{font-family:var(--mono);font-size:11px;letter-spacing:1.5px;text-transform:uppercase;color:var(--muted);margin-top:14px}
@media(max-width:900px){.stats{grid-template-columns:repeat(2,1fr)}.stat:nth-child(2){border-right:none}.stat:nth-child(-n+2){border-bottom:1px solid var(--border)}}
/* SERVICES (homepage accordion) */
.services-grid{display:grid;grid-template-columns:1fr 1.9fr;gap:70px;align-items:start}
.services-sticky{position:sticky;top:120px}
.svc-list{border-top:1px solid var(--border)}
.svc{border-bottom:1px solid var(--border);padding:30px 0;cursor:pointer;transition:padding .3s}
.svc-head{display:grid;grid-template-columns:54px 1fr auto 30px;align-items:center;gap:18px}
.svc-num{font-family:var(--mono);font-size:12px;color:var(--accent)}
.svc-name{font-size:clamp(20px,2.4vw,30px);font-weight:600;transition:color .2s}
.svc-price{font-family:var(--mono);font-size:12px;color:var(--muted);letter-spacing:.5px}
.svc-arrow{font-size:18px;color:var(--muted);transition:transform .3s,color .3s;justify-self:end}
.svc:hover .svc-name{color:var(--accent)}
.svc:hover .svc-arrow{color:var(--accent);transform:rotate(45deg)}
.svc-detail{max-height:0;overflow:hidden;transition:max-height .4s var(--ease)}
.svc.open .svc-detail{max-height:220px}
.svc.open .svc-arrow{transform:rotate(90deg);color:var(--accent)}
.svc-detail-in{padding:22px 0 4px 72px}
.svc-desc{color:var(--muted);font-size:15px;line-height:1.6;max-width:60ch}
.svc-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.svc-tags span{font-family:var(--mono);font-size:10px;letter-spacing:1px;text-transform:uppercase;color:var(--muted);border:1px solid var(--border);padding:5px 10px}
@media(max-width:900px){.services-grid{grid-template-columns:1fr;gap:40px}.services-sticky{position:static}.svc-detail-in{padding-left:0}}
/* WORK head/link/more (homepage) */
.work-head{display:flex;justify-content:space-between;align-items:flex-end;margin-bottom:48px;flex-wrap:wrap;gap:20px}
.work-link{font-family:var(--mono);font-size:12px;letter-spacing:1px;text-transform:uppercase;color:var(--muted);border-bottom:1px solid var(--border);padding-bottom:4px;transition:.2s}
.work-link:hover{color:var(--accent);border-color:var(--accent)}
.work-more{text-align:center;margin-top:44px}
.work-more a{font-family:var(--mono);font-size:13px;letter-spacing:1px;text-transform:uppercase;color:var(--muted);transition:.2s}
.work-more a:hover{color:var(--accent)}
/* PROCESS */
.proc-meta{display:inline-flex;align-items:center;gap:8px;font-family:var(--mono);font-size:12px;color:var(--muted);margin-top:18px}
.proc-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--border);border:1px solid var(--border);position:relative}
.proc-step{background:var(--bg);padding:30px 26px 34px}
.proc-week{font-family:var(--mono);font-size:10px;letter-spacing:1.5px;text-transform:uppercase;color:var(--accent);margin-bottom:18px}
.proc-node{width:11px;height:11px;border-radius:50%;background:var(--bg-3);border:1px solid var(--accent);margin-bottom:22px;position:relative}
.proc-step:hover .proc-node{background:var(--accent);box-shadow:0 0 14px var(--accent)}
.proc-num{font-weight:700;font-size:40px;color:var(--muted-2);line-height:1;margin-bottom:12px;transition:color .3s}
.proc-step:hover .proc-num{color:var(--accent)}
.proc-title{font-size:19px;font-weight:600;margin-bottom:10px}
.proc-desc{color:var(--muted);font-size:13.5px;line-height:1.55}
.proc-deliver{display:flex;flex-wrap:wrap;gap:6px;margin-top:18px}
.proc-deliver span{font-family:var(--mono);font-size:9px;letter-spacing:.5px;text-transform:uppercase;color:var(--muted);border:1px solid var(--border);padding:4px 8px}
@media(max-width:900px){.proc-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.proc-grid{grid-template-columns:1fr}}
/* OSI cards (homepage) */
.osi-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--border);border:1px solid var(--border);margin-top:64px}
.osi-card{background:var(--bg);padding:28px 26px;transition:background .3s}
.osi-card:hover{background:var(--bg-2)}
.osi-card .tag{font-family:var(--mono);font-size:10px;letter-spacing:1.6px;text-transform:uppercase;color:var(--accent);display:block;margin-bottom:12px}
.osi-card p{color:var(--muted);font-size:14px;line-height:1.55}
@media(max-width:960px){.osi-cards{grid-template-columns:1fr}}
/* CLIENTS gradient */
.clients{position:relative;overflow:hidden;padding:120px var(--gut);border-top:1px solid var(--border);background:linear-gradient(120deg,#16131f 0%,#2BD888 22%,#8A2BFF 48%,#FF5945 74%,#16131f 100%);background-size:280% 280%;animation:hue 16s ease-in-out infinite}
@keyframes hue{0%{background-position:0% 50%}50%{background-position:100% 50%}100%{background-position:0% 50%}}
.clients>*{position:relative;z-index:1}
.clients .eyebrow{color:#fff}.clients .eyebrow::before{background:#fff}
.clients .title{text-shadow:0 2px 28px rgba(0,0,0,.5)}
.clients-note{color:rgba(255,255,255,.92);margin-top:18px;max-width:560px;font-size:15px;line-height:1.6;text-shadow:0 1px 14px rgba(0,0,0,.5)}
.clients-note .accent{color:#fff;font-weight:600}
.clients-strip{display:flex;flex-wrap:wrap;align-items:center;gap:40px 56px;margin-top:50px}
.clogo{display:flex;align-items:center;gap:9px;font-family:var(--mono);font-weight:700;font-size:16px;letter-spacing:2px;color:#fff;opacity:.9;text-shadow:0 1px 8px rgba(0,0,0,.55);transition:opacity .3s}
.clogo:hover{opacity:1}
.clogo i{width:13px;height:13px;border:2px solid #fff;display:block}
.clogo:nth-child(2) i{border-radius:50%}.clogo:nth-child(3) i{transform:rotate(45deg)}.clogo:nth-child(5) i{border-radius:50% 50% 50% 0}
@media(max-width:700px){.clients-strip{gap:28px 36px}}
/* FOUNDER extras (homepage about-grid + client note) */
.about-grid{display:grid;grid-template-columns:1.3fr 1fr;gap:22px;align-items:stretch}
.aquote{background:var(--bg-2);border:1px solid var(--border);padding:40px;position:relative;display:flex;flex-direction:column;justify-content:center}
.aquote-mark{font-size:90px;line-height:.6;color:var(--accent);opacity:.25;font-weight:700;margin-bottom:10px}
.aquote-text{font-size:17px;line-height:1.55}
.tauthor{display:flex;align-items:center;gap:13px;margin-top:24px}
.tavatar{width:42px;height:42px;border-radius:50%;background:var(--bg-3);border:1px solid var(--border);display:flex;align-items:center;justify-content:center;font-weight:700;color:var(--accent)}
.tbyline{font-family:var(--mono);font-size:11px;line-height:1.6}
.tbyline strong{display:block;color:var(--fg);text-transform:uppercase;letter-spacing:.5px}
.tbyline span{color:var(--muted)}
@media(max-width:900px){.about-grid{grid-template-columns:1fr}}
/* CTA (homepage, sketch bg) */
.cta{position:relative;overflow:hidden;text-align:center;padding:150px var(--gut);border-top:1px solid var(--border);background:linear-gradient(180deg,var(--bg) 0%,#0E0B17 100%)}
.cta-sketch{position:absolute;inset:0;z-index:0;width:100%;height:100%;object-fit:cover;pointer-events:none;opacity:.25;mix-blend-mode:screen;-webkit-mask-image:radial-gradient(ellipse 82% 72% at 50% 45%,#000 52%,transparent 100%);mask-image:radial-gradient(ellipse 82% 72% at 50% 45%,#000 52%,transparent 100%)}
.cta-glow{position:absolute;left:50%;top:50%;transform:translate(-50%,-50%);width:800px;height:800px;max-width:120vw;z-index:0;background:radial-gradient(circle,rgba(255,89,69,.08),transparent 60%);pointer-events:none}
.cta .eyebrow{position:relative;z-index:2;justify-content:center}
.cta-title{position:relative;z-index:2;font-family:var(--display);font-weight:700;font-size:clamp(40px,7vw,92px);line-height:.98;letter-spacing:-.03em;margin:8px 0 26px}
.cta-title .accent{color:var(--accent)}
.cta-meta{position:relative;z-index:2;color:var(--muted);max-width:54ch;margin:0 auto 40px;font-size:16px;line-height:1.65}
.cta-btn{position:relative;z-index:2;display:inline-flex;align-items:center;gap:10px;background:var(--accent);color:#160a08;font-family:var(--mono);font-weight:700;font-size:15px;letter-spacing:1px;padding:20px 34px;transition:.25s var(--ease)}
.cta-btn:hover{box-shadow:0 0 40px rgba(255,89,69,.5);transform:translateY(-3px)}
@media(prefers-reduced-motion:reduce){
  .hero-title .ln span,.hero-sub,.hero-cta-row,.hero-meta{opacity:1;transform:none;animation:none}
  .clients{animation:none}
}