/* Layout: sticky navy "bảng lớp" header, hero band with a fading classroom photo, then a paper-white work area; each tool is its own view. */
:root{
  color-scheme:light;
  --bg:#F3F6F9; --surface:#FFFFFF; --ink:#0F2A44; --muted:#4A5D72; --line:#D5DEE8;
  --board:#0F2A44; --on-board:#FFFFFF; --on-board-muted:#C9D6E3;
  --chalk:#FFC93C; --chalk-ink:#0F2A44; --accent-ink:#8A5A00;
  --good:#1F7A4D; --good-bg:#E3F4EA; --bad:#B42318; --bad-bg:#FDE8E6;
  --focus:#2F6FB3;
  --side:#2B3A57; --side-muted:#B8C4D6;
  --st-present:#1F7A4D; --st-present-bg:#E3F4EA; --st-present-solid:#2E7D4F;
  --st-late:#8F5400; --st-late-bg:#FCF0D9; --st-late-solid:#9A6212;
  --st-excused:#5444B8; --st-excused-bg:#ECEAFB; --st-excused-solid:#5B4BC4;
  --st-absent:#B42318; --st-absent-bg:#FDE8E6; --st-absent-solid:#C0392B;
  --f-body:"Be Vietnam Pro", "Segoe UI", system-ui, -apple-system, sans-serif;
  --r:12px;
}
*{box-sizing:border-box}
[hidden]{display:none!important}
body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--f-body);font-size:16px;line-height:1.6}
body::before{content:"";position:fixed;inset:0 0 auto;height:env(safe-area-inset-top,0px);z-index:30;background:var(--board)}
img{max-width:100%}
a{color:var(--accent-ink)}
:focus-visible{outline:3px solid var(--focus);outline-offset:2px}
h1,h2,h3{line-height:1.25;text-wrap:balance;margin:0}
.wrap{max-width:1120px;margin:0 auto;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}

/* header */
.site{position:sticky;top:env(safe-area-inset-top,0px);z-index:20;background:var(--board);color:var(--on-board);border-bottom:1px solid rgba(255,255,255,.08)}
.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;padding-block:10px}
.brand{color:var(--on-board);text-decoration:none;font-weight:800;font-size:22px;letter-spacing:-.01em;display:flex;align-items:center;gap:10px}
.brand b{color:var(--chalk);font-weight:800}
.brand .logo{width:44px;height:44px;flex:none;display:block;object-fit:contain}
.site nav{display:flex;gap:4px;flex-wrap:wrap}
.site nav a{color:var(--on-board-muted);text-decoration:none;font-weight:600;font-size:15px;padding:8px 12px;border-radius:8px;min-height:40px;display:inline-flex;align-items:center}
.site nav a:hover{color:var(--on-board);background:rgba(255,255,255,.08)}
.site nav a.on{color:var(--chalk-ink);background:var(--chalk)}

/* hero */
.hero{position:relative;overflow:hidden;isolation:isolate;background-color:var(--board);background-image:radial-gradient(rgba(255,255,255,.07) 1.5px,transparent 1.5px);background-size:26px 26px;color:var(--on-board)}
.hero .wrap{position:relative;display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,1fr);gap:40px;align-items:center;padding-block:72px 84px;min-height:440px}
/* Ảnh lớp học nằm bên phải, mờ dần sang trái và xuống dưới để chữ luôn dễ đọc */
.hero-img{position:absolute;z-index:-1;top:0;right:0;width:64%;height:100%;object-fit:cover;object-position:62% 40%;opacity:.9;-webkit-mask-image:linear-gradient(to right,transparent 0%,rgba(0,0,0,.35) 22%,#000 60%),linear-gradient(to top,transparent 0%,#000 35%);mask-image:linear-gradient(to right,transparent 0%,rgba(0,0,0,.35) 22%,#000 60%),linear-gradient(to top,transparent 0%,#000 35%);-webkit-mask-composite:source-in;mask-composite:intersect}
.eyebrow{font-size:13px;font-weight:600;letter-spacing:.08em;text-transform:uppercase;color:var(--chalk)}
.hero h1{font-size:clamp(32px,5vw,52px);font-weight:800;letter-spacing:-.02em;margin-top:10px}
.hero h1 b{color:var(--chalk)}
.hero p{color:var(--on-board-muted);font-size:18px;max-width:34em;margin:16px 0 0}
.hero .actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}

/* buttons & form */
.btn{appearance:none;border:0;border-radius:10px;background:var(--chalk);color:var(--chalk-ink);font:inherit;font-weight:700;font-size:16px;padding:11px 18px;min-height:44px;cursor:pointer;display:inline-flex;align-items:center;justify-content:center;gap:8px;text-decoration:none}
.btn:hover{filter:brightness(1.05)}
.btn:disabled{opacity:.55;cursor:not-allowed}
.btn.ghost{background:transparent;color:var(--ink);border:1.5px solid var(--line)}
.btn.ghost:hover{border-color:var(--ink)}
.hero .btn.ghost,.stage .btn.ghost{color:var(--on-board);border-color:rgba(255,255,255,.35)}
.hero .btn.ghost:hover,.stage .btn.ghost:hover{border-color:var(--on-board)}
.btn.sm{min-height:36px;padding:6px 12px;font-size:14px}
label.f{display:grid;gap:6px;font-weight:600;font-size:14px;color:var(--ink)}
label.f small{font-weight:400;color:var(--muted)}
input[type=text],input[type=number],select,textarea{font:inherit;font-size:15px;color:var(--ink);background:var(--surface);border:1.5px solid var(--line);border-radius:10px;padding:10px 12px;width:100%;min-height:44px}
textarea{resize:vertical;line-height:1.5}
input:focus,select:focus,textarea:focus{border-color:var(--focus);outline:none;box-shadow:0 0 0 3px color-mix(in srgb,var(--focus) 25%,transparent)}
.check{display:flex;gap:10px;align-items:center;font-size:15px}
.check input{width:20px;height:20px;accent-color:var(--chalk)}
.row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.grid2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}

/* home sections */
main{padding-block:0 64px}
.section{padding-top:48px}
.section h2{font-size:26px;font-weight:800;letter-spacing:-.01em}
.section .lead{color:var(--muted);margin:6px 0 0;max-width:42em}
.cards{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:20px}
.cards.two{grid-template-columns:repeat(2,minmax(0,1fr))}
.card{display:flex;flex-direction:column;gap:8px;background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r);padding:20px;text-decoration:none;color:var(--ink);transition:border-color .15s,transform .15s}
.card:hover{border-color:var(--ink);transform:translateY(-2px)}
.card .tag{align-self:flex-start;font-size:12px;font-weight:600;letter-spacing:.05em;text-transform:uppercase;color:var(--muted);border:1px solid var(--line);border-radius:999px;padding:2px 10px}
.card h3{font-size:19px;font-weight:700}
.card p{margin:0;color:var(--muted);font-size:15px;flex:1}
.card .go{font-weight:700;color:var(--accent-ink);font-size:15px}
.card.post .thumb{display:block;margin:-20px -20px 8px;border-radius:var(--r) var(--r) 0 0;overflow:hidden;background:#FDE3C4}
.card.post .thumb img{display:block;width:100%;height:auto;aspect-ratio:1200/630;object-fit:cover}
.card.feature{border-color:var(--chalk);border-width:2px}
article.card:hover{transform:none}
.card .shot{display:block;margin:-6px -6px 6px;border:1.5px solid var(--line);border-radius:10px;overflow:hidden;background:var(--bg);transition:transform .2s,box-shadow .2s}
.card .shot:hover{transform:translateY(-2px);box-shadow:0 12px 28px rgba(15,42,68,.14)}
.card .shot .dots{display:flex;gap:6px;padding:8px 10px;background:var(--surface);border-bottom:1px solid var(--line)}
.card .shot .dots i{width:9px;height:9px;border-radius:50%;background:var(--line)}
.card .shot img{display:block;width:100%;height:auto;aspect-ratio:16/10;object-fit:cover;object-position:top left}
.card-acts{display:flex;gap:10px;flex-wrap:wrap;margin-top:6px}
.note{display:flex;gap:14px;align-items:flex-start;background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r);padding:18px 20px;margin-top:20px}
.note svg{flex:none;color:var(--good);margin-top:2px}
.note p{margin:0;color:var(--muted)}
.note strong{color:var(--ink)}
.cta{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:20px;align-items:center;background:var(--board);color:var(--on-board);border-radius:var(--r);padding:28px;margin-top:20px}
.cta p{margin:6px 0 0;color:var(--on-board-muted)}
.cta.lead-cta{grid-template-columns:minmax(0,1fr) minmax(0,440px);align-items:start;gap:28px;padding:32px;background-image:radial-gradient(rgba(255,255,255,.06) 1.5px,transparent 1.5px);background-size:26px 26px}
.lead-cta h2{color:var(--on-board)}
.lead-cta .perks{list-style:none;margin:18px 0 0;padding:0;display:grid;gap:10px}
.lead-cta .perks li{display:flex;gap:10px;align-items:flex-start;color:var(--on-board-muted);font-size:15px}
.lead-cta .perks li::before{content:"";flex:none;width:8px;height:8px;border-radius:2px;background:var(--chalk);margin-top:8px}
.lead-cta .perks b{color:var(--on-board)}
.lead-form{background:var(--surface);color:var(--ink);border-radius:12px;padding:20px;display:grid;gap:14px}
.lead-form h3{font-size:18px;font-weight:800}
.lead-form label.f abbr{color:var(--accent-ink);text-decoration:none}
.lead-form .btn{width:100%}
.lead-form .privacy{margin-top:-2px}
.lead-done{display:grid;gap:12px}
.lead-done h3{font-size:18px;font-weight:800}
.lead-done p{margin:0;color:var(--muted);font-size:15px}

/* tool views */
.tool-head{padding-block:28px 8px}
.back{display:inline-flex;align-items:center;gap:6px;font-weight:600;font-size:15px;color:var(--muted);text-decoration:none;min-height:40px}
.back:hover{color:var(--ink)}
.tool-head h1{font-size:clamp(26px,4vw,36px);font-weight:800;letter-spacing:-.01em;margin-top:4px}
.tool-head p{color:var(--muted);margin:8px 0 0;max-width:46em}
.panel{background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r);padding:20px;display:grid;gap:16px;align-content:start;min-width:0}
.panel h2{font-size:17px;font-weight:700}
.split{display:grid;grid-template-columns:minmax(0,340px) minmax(0,1fr);gap:20px;margin-top:20px;align-items:start}
.hint{font-size:14px;color:var(--muted);margin:0}
.status{font-size:14px;color:var(--muted);min-height:1.5em;margin:0}
.privacy{font-size:13px;color:var(--muted);display:flex;gap:8px;align-items:flex-start;margin:0}
.privacy svg{flex:none;color:var(--good);margin-top:3px}

/* pricing */
.plans{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px;margin-top:24px;align-items:stretch}
.plan{position:relative;background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r);padding:22px 20px;display:flex;flex-direction:column;gap:16px;min-width:0}
/* subgrid: tên gói, giá, danh sách, nút ở các thẻ thẳng hàng nhau */
@supports (grid-template-rows:subgrid){ .plan{display:grid;grid-row:span 4;grid-template-rows:subgrid;gap:16px} .plan .btn{align-self:end} }
.plan.hot{border:2px solid var(--chalk);box-shadow:0 10px 28px rgba(15,42,68,.12)}
.plan .badge{position:absolute;top:-12px;left:20px;background:var(--chalk);color:var(--chalk-ink);font-size:12px;font-weight:700;letter-spacing:.04em;text-transform:uppercase;border-radius:999px;padding:3px 10px}
.plan h2{font-size:19px;font-weight:800}
.plan .for{margin:4px 0 0;color:var(--muted);font-size:14px}
.plan .price{display:grid;gap:4px;padding-bottom:16px;border-bottom:1px solid var(--line)}
.plan .amt{font-size:25px;font-weight:800;letter-spacing:-.02em;line-height:1.15}
.plan .amt small{white-space:nowrap;font-size:15px;font-weight:600;color:var(--muted);letter-spacing:0}
.plan .amt.quote{font-size:22px}
.plan .deal{align-self:flex-start;font-size:13px;font-weight:700;color:var(--good);background:var(--good-bg);border-radius:6px;padding:2px 8px}
.plan .feats{list-style:none;margin:0;padding:0;display:grid;gap:12px;flex:1;align-content:start}
.plan .feats li{display:flex;gap:10px;align-items:flex-start;font-size:15px}
.plan .feats .ic{flex:none;margin-top:2px;color:var(--good)}
.plan .feats li.no{color:var(--muted)}
.plan .feats li.no .ic{color:var(--bad)}
.plan .feats li.no > span{text-decoration:line-through;text-decoration-color:color-mix(in srgb,var(--muted) 60%,transparent)}
.sr{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap}
.plan .btn{width:100%}
.price-note{margin-top:20px;color:var(--muted);font-size:14px}
@media (max-width:1060px){ .plans{grid-template-columns:repeat(2,minmax(0,1fr));row-gap:28px} }
@media (max-width:560px){ .plans{grid-template-columns:minmax(0,1fr)} }

/* service */
.dv-split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,560px);gap:40px;margin-top:32px;align-items:start}
.dv-intro{padding-top:8px}
.dv-intro .eyebrow{color:var(--accent-ink)}
.dv-intro h2{font-size:clamp(24px,3vw,30px);font-weight:800;letter-spacing:-.01em;margin-top:6px}
.dv-intro p{color:var(--muted);margin:12px 0 0;max-width:34em}
.dv-contact{list-style:none;margin:24px 0 0;padding:0;display:grid;gap:12px}
.dv-contact li{display:grid;gap:2px;padding-left:14px;border-left:3px solid var(--chalk)}
.dv-contact span{font-size:13px;color:var(--muted)}
.dv-contact a{font-weight:700;color:var(--ink);text-decoration:none}
.dv-contact a:hover{text-decoration:underline}
@media (max-width:860px){ .dv-split{grid-template-columns:minmax(0,1fr);gap:24px} }
.steps{list-style:none;margin:28px 0 0;padding:0;display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:20px}
.steps li{position:relative;display:grid;gap:14px;align-content:start;justify-items:center;text-align:center}
.steps li:not(:last-child)::after{content:"";position:absolute;top:27px;left:calc(50% + 40px);right:calc(-50% - 20px + 40px);height:3px;border-radius:3px;background:repeating-linear-gradient(90deg,var(--chalk) 0 10px,transparent 10px 16px)}
.st-ic{position:relative;z-index:1;width:56px;height:56px;border-radius:50%;display:grid;place-items:center;background:var(--board);color:var(--chalk);box-shadow:0 0 0 5px color-mix(in srgb,var(--chalk) 30%,transparent)}
.st-n{display:block;font-size:12px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--accent-ink)}
.steps h3{font-size:17px;font-weight:700;margin-top:2px}
.steps p{margin:4px auto 0;font-size:14px;color:var(--muted);max-width:22em}
@media (max-width:760px){
  .steps{grid-template-columns:minmax(0,1fr);gap:22px}
  .steps li{grid-template-columns:56px minmax(0,1fr);gap:16px;justify-items:start;text-align:left}
  .steps p{margin-left:0}
  .steps li:not(:last-child)::after{top:68px;bottom:-14px;left:26px;right:auto;width:3px;height:auto;background:repeating-linear-gradient(180deg,var(--chalk) 0 8px,transparent 8px 14px)}
}
.msg-box{background:var(--bg);border:1.5px dashed var(--line);border-radius:10px;padding:16px;display:grid;gap:10px}
.placeholder{background:var(--chalk);color:var(--chalk-ink);border-radius:4px;padding:0 4px;font-weight:600}

/* blog & about */
.post-meta{font-size:14px;color:var(--muted);margin-top:8px}
.article{max-width:68ch;padding-block:8px 24px}
.article h2{font-size:22px;font-weight:800;margin-top:32px}
.article p,.article li{font-size:17px;line-height:1.75}
.article p{margin:12px 0 0}
.article ol,.article ul{margin:12px 0 0;padding-left:24px;display:grid;gap:8px}
.article .callout{background:var(--surface);border:1.5px solid var(--line);border-radius:10px;padding:16px 18px;margin-top:20px}
.article .callout p{margin:0;font-size:16px}
.art-cover{display:block;max-width:360px;width:100%;height:auto;margin:24px auto 0;border-radius:12px;box-shadow:0 12px 32px rgba(15,42,68,.16)}
.article blockquote{margin:16px 0 0;padding:14px 18px;border-left:4px solid var(--chalk);background:var(--surface);border-radius:0 10px 10px 0;font-size:16px;line-height:1.7}
.tbl-wrap{overflow-x:auto;margin-top:14px;border:1.5px solid var(--line);border-radius:10px;background:var(--surface)}
.article table{width:100%;border-collapse:collapse;font-size:16px}
.article th,.article td{text-align:left;padding:10px 14px;border-bottom:1px solid var(--line);vertical-align:top}
.article thead th{font-size:13px;letter-spacing:.04em;text-transform:uppercase;color:var(--muted);background:var(--bg)}
.article tbody tr:last-child>*{border-bottom:0}
.article tbody th{font-weight:700;white-space:nowrap}
.dl-box{display:grid;grid-template-columns:120px minmax(0,1fr);gap:20px;align-items:start;margin-top:20px;padding:20px;background:var(--surface);border:2px solid var(--chalk);border-radius:var(--r)}
.dl-cover{width:120px;height:auto;border-radius:6px;box-shadow:0 6px 16px rgba(15,42,68,.18)}
.dl-body{display:grid;gap:12px;justify-items:start}
.dl-body h3{font-size:19px;font-weight:800}
.dl-body .dl-meta{margin:-6px 0 0;font-size:14px;color:var(--muted)}
.dl-wait{display:grid;gap:10px;width:100%}
.dl-wait .dl-count{margin:0;font-size:15px}
.dl-bar{height:8px;border-radius:99px;background:var(--bg);overflow:hidden}
.dl-bar span{display:block;height:100%;width:0;background:var(--chalk);transition:width 1s linear}
.dl-tip{background:var(--bg);border-radius:10px;padding:12px 14px}
.dl-tip span{font-size:12px;font-weight:700;letter-spacing:.05em;text-transform:uppercase;color:var(--accent-ink)}
.dl-tip p{margin:4px 0 0;font-size:15px;line-height:1.6}
.dl-box:has(.dl-cover[hidden]){grid-template-columns:minmax(0,1fr)}
@media (max-width:560px){ .dl-box{grid-template-columns:minmax(0,1fr)} .dl-cover{width:110px} }
.article .next{display:flex;gap:12px;flex-wrap:wrap;margin-top:28px}
.values{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px;margin-top:16px}
.values div{background:var(--surface);border:1.5px solid var(--line);border-radius:10px;padding:18px}
.values h3{font-size:17px;font-weight:700}
.values p{margin:6px 0 0;font-size:15px;color:var(--muted)}
@media (max-width:760px){ .values{grid-template-columns:minmax(0,1fr)} }
footer{background:var(--board);color:var(--on-board-muted);font-size:14px;margin-top:8px}
footer a{color:var(--on-board-muted);text-decoration:none}
footer a:hover{color:var(--on-board);text-decoration:underline}
.ft-main{display:grid;grid-template-columns:minmax(0,1.3fr) minmax(0,.8fr) minmax(0,.9fr) minmax(0,320px);gap:32px;padding-block:44px 32px}
.fb-frame{margin-top:18px;width:100%;max-width:320px;height:130px;border-radius:10px;overflow:hidden;background:rgba(255,255,255,.06)}
.fb-frame iframe{display:block;border:0;width:100%;height:130px}
.ft-brand .brand{font-size:20px}
.ft-brand p{margin:12px 0 0;max-width:30em;line-height:1.6}
.ft-trust{list-style:none;margin:16px 0 0;padding:0;display:grid;gap:8px}
.ft-trust li{display:flex;gap:8px;align-items:flex-start}
.ft-trust svg{flex:none;color:var(--chalk);margin-top:2px}
.ft-col h2{font-size:13px;font-weight:700;letter-spacing:.08em;text-transform:uppercase;color:var(--chalk)}
.ft-col ul{list-style:none;margin:14px 0 0;padding:0;display:grid;gap:10px}
.ft-bottom{border-top:1px solid rgba(255,255,255,.12);padding-block:18px 24px;display:flex;justify-content:center;text-align:center;gap:12px;flex-wrap:wrap;font-size:13px}
@media (max-width:1060px){ .ft-main{grid-template-columns:minmax(0,1fr) minmax(0,1fr) minmax(0,320px)} .ft-brand{grid-column:1/-1} }
@media (max-width:760px){ .ft-main{grid-template-columns:repeat(2,minmax(0,1fr))} .ft-contact{grid-column:1/-1} }
@media (max-width:560px){ .ft-main{grid-template-columns:minmax(0,1fr);gap:28px;padding-block:36px 24px} }

@media (max-width:860px){
  .hero .wrap{grid-template-columns:minmax(0,1fr);padding-block:40px 44px;min-height:0}
  .hero-img{width:100%;opacity:.35;object-position:70% 30%;-webkit-mask-image:linear-gradient(to top,transparent 0%,#000 60%);mask-image:linear-gradient(to top,transparent 0%,#000 60%)}
  .cards{grid-template-columns:repeat(2,minmax(0,1fr))}
  .split{grid-template-columns:minmax(0,1fr)}
  .cta.lead-cta{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:560px){
  .cards,.cards.two,.grid2,.steps{grid-template-columns:minmax(0,1fr)}
  .opts{grid-template-columns:minmax(0,1fr)}
  .cta,.cta.lead-cta{grid-template-columns:minmax(0,1fr)}
  .cta.lead-cta{padding:24px 16px}
  .stage{padding:20px 16px;min-height:300px}
}
@media (prefers-reduced-motion: reduce){ *{transition:none!important;scroll-behavior:auto!important} }

/* nút liên hệ nổi */
.fab{position:fixed;right:max(16px,env(safe-area-inset-right));bottom:max(16px,env(safe-area-inset-bottom));z-index:40;display:grid;gap:12px;justify-items:end}
.fab a{position:relative;width:56px;height:56px;border-radius:50%;display:grid;place-items:center;color:#fff;text-decoration:none;box-shadow:0 6px 18px rgba(15,42,68,.28),0 0 0 3px rgba(255,255,255,.9);transition:transform .15s}
.fab a:hover,.fab a:focus-visible{transform:scale(1.08)}
.fab a:focus-visible{outline:3px solid var(--chalk);outline-offset:3px}
.fab .zl{background:#fff}
.fab .zl img{width:42px;height:42px;display:block}
.fab .ph{background:#1F9D55}
.fab .ms{background:#fff}
.fab .ms img{width:34px;height:34px;display:block}
.fab .tip{position:absolute;right:68px;top:50%;transform:translateY(-50%);white-space:nowrap;background:var(--board);color:var(--on-board);font-size:13px;font-weight:600;padding:6px 10px;border-radius:8px;opacity:0;pointer-events:none;transition:opacity .15s}
.fab a:hover .tip,.fab a:focus-visible .tip{opacity:1}
@media (prefers-reduced-motion: no-preference){
  .fab .zl::after{content:"";position:absolute;inset:0;border-radius:50%;box-shadow:0 0 0 0 rgba(0,104,255,.5);animation:fabPulse 2.4s ease-out infinite}
  @keyframes fabPulse{0%{box-shadow:0 0 0 0 rgba(0,104,255,.45)}70%{box-shadow:0 0 0 14px rgba(0,104,255,0)}100%{box-shadow:0 0 0 0 rgba(0,104,255,0)}}
  .fab .ph svg{transform-origin:50% 50%;animation:phRing 4s ease-in-out infinite}
  .fab .ph:hover svg{animation-play-state:paused}
  @keyframes phRing{
    0%,22%,100%{transform:rotate(0)}
    2%,6%,10%,14%{transform:rotate(-16deg)}
    4%,8%,12%,16%{transform:rotate(16deg)}
    18%{transform:rotate(-8deg)}20%{transform:rotate(8deg)}
  }
}
@media (max-width:560px){ .fab a{width:50px;height:50px} .fab .zl img{width:38px;height:38px} .fab .ms img{width:30px;height:30px} .fab{gap:10px} footer{padding-bottom:72px} }
@media print{ .fab{display:none} }

/* ứng dụng mẫu: dải thẻ chạy ngang liên tục */
.apps-head{display:flex;justify-content:space-between;align-items:flex-end;gap:16px;flex-wrap:wrap}
.marquee{--gap:16px;display:flex;gap:var(--gap);overflow:hidden;margin-top:22px;padding-block:6px 10px}
.marquee-track{list-style:none;margin:0;padding:0;display:flex;gap:var(--gap);flex:none;min-width:100%;animation:marquee 48s linear infinite}
.marquee:hover .marquee-track,.marquee:focus-within .marquee-track{animation-play-state:paused}
@keyframes marquee{to{transform:translateX(calc(-100% - var(--gap)))}}
@media (prefers-reduced-motion: reduce){
  .marquee{overflow-x:auto;-webkit-mask-image:none;mask-image:none;scroll-snap-type:x mandatory}
  .marquee-track{animation:none} .marquee-track[aria-hidden]{display:none}
  .sample{scroll-snap-align:start}
}
/* thẻ ứng dụng mẫu (lấy từ sample.html) */
.sample{flex:none;width:340px;display:flex;flex-direction:column;background:var(--surface);border:1.5px solid var(--line);border-radius:var(--r);overflow:hidden;min-width:0}
.mock{background:var(--bg);border-bottom:1px solid var(--line);padding:20px;min-height:210px;display:flex;align-items:center;justify-content:center}
.screen{width:100%;max-width:340px;background:var(--surface);border:1px solid var(--line);border-radius:10px;box-shadow:0 8px 20px rgba(15,42,68,.08);padding:12px 14px;font-size:13px;line-height:1.45;display:grid;gap:8px;color:var(--ink)}
.screen .top{display:flex;justify-content:space-between;align-items:center;gap:8px;font-weight:700}
.screen .top span{font-weight:500;color:var(--muted);font-size:12px}
.lb{display:grid;grid-template-columns:16px 46px minmax(0,1fr) 34px;gap:8px;align-items:center;font-variant-numeric:tabular-nums}
.lb b{color:var(--accent-ink)}
.lb .track{height:8px;border-radius:99px;background:var(--line);overflow:hidden}
.lb .track i{display:block;height:100%;border-radius:inherit;background:var(--chalk)}
.lb .pts{text-align:right;font-weight:700}
.phone{width:210px;max-width:100%;background:var(--surface);border:7px solid var(--board);border-radius:26px;padding:12px 10px;display:grid;gap:8px;font-size:12px;line-height:1.45;color:var(--ink);box-shadow:0 8px 20px rgba(15,42,68,.12)}
.phone .who{font-weight:700;font-size:12px;display:flex;gap:6px;align-items:center}
.phone .who i{width:22px;height:22px;border-radius:50%;background:var(--chalk);display:inline-block}
.bubble{background:var(--bg);border-radius:12px;padding:8px 10px}
.bubble strong{display:block;font-size:12px}
.bubble.ok{background:var(--st-present-bg);color:var(--st-present)}
.qrow{display:flex;justify-content:space-between;align-items:center;gap:8px;padding:6px 0;border-top:1px solid var(--line)}
.qrow:first-of-type{border-top:0}
.qrow em{font-style:normal;font-size:11px;font-weight:600;color:var(--muted);border:1px solid var(--line);border-radius:99px;padding:0 7px;white-space:nowrap}
.mini-btn{justify-self:start;background:var(--chalk);color:var(--chalk-ink);border-radius:7px;padding:5px 12px;font-weight:700;font-size:12px}
.kv{display:flex;justify-content:space-between;gap:8px;color:var(--muted)}
.kv b{color:var(--ink);font-weight:600}
.seat{height:8px;border-radius:99px;background:var(--line);overflow:hidden}
.seat i{display:block;height:100%;width:80%;background:var(--st-present-solid)}
.fake-search{border:1px solid var(--line);border-radius:8px;padding:6px 10px;color:var(--muted);font-size:12px}
.tiles-mini{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px}
.tiles-mini div{background:var(--bg);border-radius:8px;padding:8px;font-size:12px;font-weight:600;display:grid;gap:4px}
.tiles-mini div span{font-size:10px;font-weight:700;letter-spacing:.06em;color:var(--accent-ink)}
.sample-body{padding:18px 20px 20px;display:grid;gap:8px;flex:1;align-content:start}
.badge-mau{justify-self:start;font-size:11px;font-weight:700;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);border:1px solid var(--line);border-radius:999px;padding:1px 9px}
.sample h3{font-size:19px;font-weight:700}
.sample p{margin:0;color:var(--muted);font-size:15px}
.sample .fit{font-size:13px;color:var(--muted)}
.sample .fit b{color:var(--ink);font-weight:600}
.sample .go{font-weight:700;color:var(--accent-ink);text-decoration:none;margin-top:6px;font-size:15px}
.sample .go:hover{text-decoration:underline}
.badge-mau.ai{color:var(--accent-ink);border-color:currentColor}
.chat{display:grid;gap:6px}
.chat .bubble{max-width:88%}
.chat .bubble.me{justify-self:end;background:var(--chalk);color:var(--chalk-ink)}
.score{display:grid;grid-template-columns:minmax(0,1fr) 40px;gap:8px;align-items:center}
.score .track{height:6px;border-radius:99px;background:var(--line);overflow:hidden;grid-column:1/-1}
.score .track i{display:block;height:100%;background:var(--st-excused-solid)}
.score b{text-align:right;font-variant-numeric:tabular-nums}
.ai-note{background:var(--st-excused-bg);color:var(--st-excused);border-radius:8px;padding:6px 8px;font-size:12px}

@media (max-width:560px){ .sample{width:280px} .apps-head .btn{width:100%} }
.sample .mock{height:260px;min-height:0;overflow:hidden}
/* thẻ ứng dụng mẫu gọn hơn */
.sample{width:260px}
.sample .mock{height:180px;padding:12px}
.sample .mock .screen{font-size:11px;padding:9px 10px;gap:5px;max-width:230px}
.sample .mock .screen .top span{font-size:10px}
.sample .mock .phone{width:170px;font-size:10px;padding:9px 8px;gap:6px;border-width:5px;border-radius:20px}
.sample .mock .phone .who{font-size:10px}
.sample .mock .bubble{padding:6px 8px}
.sample .mock .bubble strong{font-size:10px}
.sample .mock .qrow em,.sample .mock .tiles-mini div span{font-size:9px}
.sample .mock .tiles-mini div,.sample .mock .ai-note,.sample .mock .fake-search,.sample .mock .mini-btn{font-size:10px}
.sample .mock .lb{grid-template-columns:12px 38px minmax(0,1fr) 28px;gap:6px}
.sample-body{padding:12px 14px 14px;gap:6px}
.sample h3{font-size:16px}
.sample p{font-size:13px;line-height:1.5}
.sample .fit{font-size:12px}
.sample .go{font-size:13px;margin-top:2px}
@media (max-width:560px){ .sample{width:240px} }
.sample .mock{height:196px;align-items:flex-start}
.sample .mock .chat .bubble{font-size:10px;line-height:1.4}

/* neo trong trang (#lien-he, #h-soan) không bị header dính che mất */
[id]{scroll-margin-top:88px}

/* bẫy bot trong form: ẩn với người dùng */
.hp{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}

/* danh sách liên hệ trong bài viết (trang Về chúng tôi) */
.article .dv-contact{padding-left:0;margin-top:16px;gap:12px}
.article .dv-contact li{font-size:16px;line-height:1.5}
.article .dv-contact a{word-break:break-word}