/* ==========================================================================
   AI ACADEMY — Landing Page "Làm Chủ Claude AI"
   styles.css — responsive, hiện đại, chuyên nghiệp
   Bảng màu lấy từ nhận diện AI ACADEMY (cam #F26522 + đen/graphite)
   ========================================================================== */

:root{
  --brand:#F26522;          /* cam AI ACADEMY */
  --brand-dark:#d9541a;
  --brand-soft:#FFF1E9;
  --ink:#16181D;            /* nền tối / chữ đậm */
  --ink-2:#232733;
  --graphite:#3A3F4B;
  --text:#2A2E37;
  --muted:#5f6672;
  --line:#E7E9EE;
  --bg:#ffffff;
  --bg-soft:#F7F8FA;
  --ok:#1f9d55;
  --radius:16px;
  --radius-sm:10px;
  --shadow:0 10px 30px rgba(20,24,33,.08);
  --shadow-lg:0 24px 60px rgba(20,24,33,.16);
  --maxw:1140px;
  --font:'Be Vietnam Pro',-apple-system,BlinkMacSystemFont,'Segoe UI',Roboto,Arial,sans-serif;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;font-family:var(--font);color:var(--text);
  background:var(--bg);line-height:1.65;font-size:17px;
  -webkit-font-smoothing:antialiased;overflow-x:hidden;
}
img{max-width:100%;display:block}
a{color:inherit;text-decoration:none}
h1,h2,h3,h4{line-height:1.25;color:var(--ink);margin:0 0 .5em}
h2{font-size:clamp(24px,3.4vw,36px);font-weight:800}
h3{font-size:clamp(19px,2.2vw,24px);font-weight:700}
p{margin:0 0 1em}
.container{max-width:var(--maxw);margin:0 auto;padding:0 20px}
.section{padding:36px 0}
.section--soft{background:var(--bg-soft)}
.section--ink{background:var(--ink);color:#EAECEF}
.section--ink h2,.section--ink h3{color:#fff}
.eyebrow{font-weight:700;letter-spacing:.08em;text-transform:uppercase;font-size:18px;margin-bottom:10px}
.center{text-align:center}
.lead{font-size:19px;color:var(--muted);max-width:760px}
.center .lead{margin-left:auto;margin-right:auto}

/* ---------- Buttons ---------- */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  font-family:inherit;font-weight:700;font-size:16px;cursor:pointer;
  padding:15px 28px;border-radius:999px;border:2px solid transparent;
  transition:transform .12s ease,box-shadow .2s ease,background .2s ease;
  text-align:center;line-height:1.2;
}
.btn:active{transform:translateY(1px)}
.btn--primary{background:var(--brand);color:#fff;box-shadow:0 8px 20px rgba(242,101,34,.32)}
.btn--primary:hover{background:var(--brand-dark)}
.btn--ghost{background:transparent;color:var(--brand);border-color:var(--brand)}
.btn--ghost:hover{background:var(--brand-soft)}
.btn--zalo{background:#0068FF;color:#fff;border-color:#0068FF}
.btn--zalo:hover{filter:brightness(.94)}
.btn--lg{padding:17px 34px;font-size:17px}
.btn--block{width:100%}
.cta-note{font-size:14px;color:var(--muted);margin-top:12px}
.section--ink .cta-note{color:#aeb4bf}
.btn-row{display:flex;gap:14px;flex-wrap:wrap}
.center .btn-row{justify-content:center}

/* ---------- Top nav ---------- */
.nav{position:sticky;top:0;z-index:60;background:rgba(255,255,255,.94);
  backdrop-filter:blur(8px);border-bottom:1px solid var(--line)}
.nav__in{display:flex;align-items:center;justify-content:space-between;height:68px;gap:16px}
.nav__brand{flex:none;display:flex;align-items:center}
.nav__logo{height:78px;width:auto}
.nav__menu{display:flex;align-items:center;gap:6px;flex-wrap:nowrap}
.nav__link{font-weight:600;font-size:14.5px;color:var(--graphite);padding:8px 12px;border-radius:8px;
  white-space:nowrap;transition:color .15s,background .15s;position:relative}
.nav__link:hover{color:var(--brand);background:var(--brand-soft)}
.nav__menu-cta{padding:10px 18px;font-size:14px;margin-left:6px}
/* Hamburger */
.nav__toggle{display:none;flex-direction:column;justify-content:center;gap:5px;width:44px;height:44px;
  background:none;border:none;cursor:pointer;padding:10px;flex:none}
.nav__toggle span{display:block;height:2.5px;width:100%;background:var(--ink);border-radius:2px;transition:.25s}
.nav__toggle[aria-expanded="true"] span:nth-child(1){transform:translateY(7.5px) rotate(45deg)}
.nav__toggle[aria-expanded="true"] span:nth-child(2){opacity:0}
.nav__toggle[aria-expanded="true"] span:nth-child(3){transform:translateY(-7.5px) rotate(-45deg)}

/* Anchor jump offset so sticky header không che tiêu đề mục */
section[id],a[id]{scroll-margin-top:84px}

/* Nav gọn lại thành hamburger khi hẹp */
@media (max-width:1024px){
  .nav__toggle{display:flex}
  .nav__menu{position:absolute;top:68px;left:0;right:0;flex-direction:column;align-items:stretch;
    background:#fff;border-bottom:1px solid var(--line);box-shadow:var(--shadow-lg);
    padding:10px 20px 18px;gap:2px;max-height:0;overflow:hidden;opacity:0;pointer-events:none;
    transition:max-height .3s ease,opacity .2s ease}
  .nav__menu.is-open{max-height:82vh;overflow:auto;opacity:1;pointer-events:auto}
  .nav__link{padding:14px 6px;font-size:16px;border-bottom:1px solid var(--line);border-radius:0}
  .nav__link:hover{background:none;color:var(--brand)}
  .nav__menu-cta{margin:14px 0 0;width:100%;justify-content:center;padding:14px}
}

.title_color{
  color: #F26522;
}

/* ---------- Hero ---------- */
.hero{position:relative;background:
  radial-gradient(1200px 500px at 80% -10%,rgba(242,101,34,.20),transparent 60%),
  linear-gradient(160deg,#14161B 0%,#20242E 60%,#262b36 100%);
  color:#EAECEF;overflow:hidden}
.hero__grid{display:grid;grid-template-columns:1.15fr .85fr;gap:40px;align-items:center;
  padding:64px 0 56px}
.hero__eyebrow{color:#fff;background:rgba(242,101,34,.18);border:1px solid rgba(242,101,34,.5);
  display:inline-block;padding:6px 14px;border-radius:999px;font-weight:700;font-size:13px;
  letter-spacing:.06em;margin-bottom:18px}
.hero h1{color:#fff;font-size:clamp(30px,4.6vw,50px);font-weight:800;letter-spacing:-.01em;margin-bottom:14px}
.hero .accent{color:var(--brand); font-size: 52px}
.hero__sub{font-size:clamp(17px,2vw,20px);color:#C7CCD6;margin-bottom:22px}
.hero__body{color:#AEB4BF;max-width:560px}
.hero__teacher{margin:22px 0;padding:16px 18px;border-left:3px solid var(--brand);
  background:rgba(255,255,255,.04);border-radius:0 12px 12px 0}
.hero__teacher .lbl{font-size:13px;text-transform:uppercase;letter-spacing:.08em;color:#9aa1ad}
.hero__teacher .name{font-size:20px;font-weight:800;color:#fff}
.hero__teacher .role{color:var(--brand);font-weight:700;font-size:14px}
.hero__facts{list-style:none;padding:0;margin:22px 0 26px;display:grid;gap:8px}
.hero__facts li{position:relative;padding-left:26px;color:#D4D8E0;font-size:15.5px}
.hero__facts li::before{content:"";position:absolute;left:0;top:9px;width:12px;height:12px;
  border-radius:50%;background:var(--brand)}
.hero__media{position:relative;display:flex;justify-content:center;align-items:flex-end}
.hero__portrait{width:100%;max-width:420px;filter:drop-shadow(0 20px 40px rgba(0,0,0,.45));
  position:relative;z-index:2}
.hero__halo{position:absolute;inset:auto 0 0 0;margin:auto;width:360px;height:360px;
  background:radial-gradient(circle,rgba(242,101,34,.35),transparent 65%);z-index:1;bottom:-30px}

/* ---------- Trust bar (Khối 2 & 11) ---------- */
.trust{padding:34px 0;border-bottom:1px solid var(--line)}
.trust p{margin:0 auto 6px;max-width:820px;text-align:center;color:var(--muted)}
.logo-grid{display:grid;grid-template-columns:repeat(5,1fr);gap:14px;margin-top:26px}
.logo-cell{display:flex;flex-direction:column;align-items:center;justify-content:center;
  min-height:96px;background:#fff;border:1px solid var(--line);border-radius:12px;padding:12px 10px;
  color:var(--graphite);text-align:center;overflow:hidden;position:relative}
.logo-cell img{max-height:56px;width:auto;filter:grayscale(1);opacity:.85;transition:.2s; filter:none;opacity:1}
/* .logo-cell:hover img{filter:none;opacity:1} */
.logo-cell.is-empty{border-style:dashed;border-color:#CDD2DB;background:#FBFBFD}
.logo-cell .logo-name{font-weight:700;font-size:14.5px;line-height:1.2}
.logo-cell .logo-tag{font-size:10.5px;letter-spacing:.04em;color:#a2a8b3;margin-bottom:4px;text-transform:uppercase}

/* ---------- Problems (Khối 3) ---------- */
.prob-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:16px;margin-top:8px}
.prob{display:flex;gap:14px;background:#fff;border:1px solid var(--line);
  border-radius:var(--radius-sm);padding:18px 20px;box-shadow:var(--shadow)}
.prob .x{flex:none;width:26px;height:26px;border-radius:50%;background:var(--brand-soft);
  color:var(--brand);display:grid;place-items:center;font-weight:800;margin-top:2px}
.prob p{margin:0;font-size:16px}
.prob-note{margin-top:26px;font-size:18px;font-weight:600;color:var(--ink);text-align:center;
  max-width:820px;margin-left:auto;margin-right:auto}

/* ---------- Before / After (Khối 4) ---------- */
.ba-wrap{
  position:relative;margin-top:34px;
  background:linear-gradient(160deg,#FFE4CC 0%,#FFF3E8 45%,#FFF 85%);
  border-radius:28px;padding:40px clamp(14px,3.5vw,40px) 34px;
  border:1px solid #FBC896;
  box-shadow:0 35px 70px -30px rgba(242,101,34,.3);
  overflow:hidden;
}
.ba-wrap::before{
  content:"";position:absolute;top:-130px;left:-100px;width:320px;height:320px;border-radius:50%;
  background:radial-gradient(circle,rgba(242,101,34,.28),transparent 70%);pointer-events:none;
}
.ba-lead{text-align:center;max-width:780px;margin:0 auto 28px;font-size:19px;font-weight:600;color:var(--ink);position:relative;z-index:1}
.ba{
  display:grid;grid-template-columns:1fr auto 1fr;gap:0;align-items:stretch;
  border-radius:20px;overflow:hidden;position:relative;z-index:1;
  box-shadow:0 25px 55px -20px rgba(20,24,33,.35);
}
.ba__col{padding:8px 0}
.ba__col--before{background:#2A2E37}
.ba__col--after{background:linear-gradient(165deg,var(--brand) 0%,#FF8A3D 100%)}
.ba__head{font-weight:800;padding:22px 26px;font-size:18px;border-bottom:1px solid rgba(255,255,255,.14)}
.ba__col--before .ba__head{color:#fff}
.ba__col--after .ba__head{color:#fff}
.ba__row{padding:15px 26px;border-bottom:1px solid rgba(255,255,255,.1);font-size:15.5px;min-height:58px;display:flex;align-items:center;gap:12px}
.ba__row:last-child{border-bottom:none}
.ba__col--before .ba__row{color:#D7DAE0}
.ba__col--after .ba__row{font-weight:700;color:#fff}
.ba__ico{
  flex:none;width:24px;height:24px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;font-size:12px;font-weight:800;
}
.ba__ico--x{background:rgba(229,72,77,.22);color:#FF8A8D}
.ba__ico--ok{background:rgba(255,255,255,.24);color:#fff}
.ba__arrow{
  display:flex;align-items:center;justify-content:center;background:#fff;
  width:56px;position:relative;z-index:2;
}
.ba__arrow span{
  width:40px;height:40px;border-radius:50%;background:linear-gradient(135deg,var(--brand),#FF3D3D);
  color:#fff;font-size:18px;font-weight:800;display:flex;align-items:center;justify-content:center;
  box-shadow:0 10px 22px -6px rgba(229,72,77,.6);
}
.ba-foot{text-align:center;color:var(--muted);font-size:15px;margin-top:18px;font-style:italic}

@media (max-width:760px){
  .ba-wrap{padding:26px 16px 24px;border-radius:20px}
  .ba{grid-template-columns:1fr}
  .ba__arrow{width:100%;padding:10px 0}
  .ba__arrow span{transform:rotate(90deg)}
}
.border{border-color: #F26522;}

/* ---------- 3 competencies (Khối 5) ---------- */
.cards3{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;margin-top:10px}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:28px 24px;box-shadow:var(--shadow);transition:transform .15s,box-shadow .2s}
.card:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.card .ico{width:52px;height:52px;border-radius:14px;background:var(--brand-soft);color:var(--brand);
  display:grid;place-items:center;margin-bottom:16px}
.card .ico svg{width:28px;height:28px}
.card h3{font-size:19px;margin-bottom:8px}
.card p{margin:0;color:var(--muted);font-size:15.5px}

/* ---------- Audience (Khối 6) ---------- */
.aud-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.aud{background:#fff;border:1px solid var(--line);border-top:4px solid var(--brand);
  border-radius:var(--radius);padding:26px 24px;box-shadow:var(--shadow)}
.aud h3{font-size:18px}
.aud p{margin:0;color:var(--muted);font-size:15.5px}
.aud-note{margin-top:26px;text-align:center;font-size:17px;color:var(--ink)}

/* ---------- Curriculum accordion (Khối 7) ---------- */
.curr-src{text-align:center;color:var(--muted);font-size:14px;font-style:italic;margin:-8px auto 26px;max-width:760px}
.acc{max-width:900px;margin:0 auto}
.acc__item{border:1px solid var(--line);border-radius:var(--radius-sm);margin-bottom:14px;
  background:#fff;box-shadow:var(--shadow);overflow:hidden}
.acc__head{display:flex;align-items:center;gap:16px;width:100%;text-align:left;
  padding:20px 22px;background:none;border:none;cursor:pointer;font-family:inherit}
.acc__num{flex:none;width:44px;height:44px;border-radius:12px;background:var(--ink);color:#fff;
  font-weight:800;display:grid;place-items:center;font-size:15px}
.acc__item.is-open .acc__num{background:var(--brand)}
.acc__title{flex:1;font-weight:700;font-size:16.5px;color:var(--ink)}
.acc__chev{flex:none;color:var(--muted);transition:transform .25s}
.acc__item.is-open .acc__chev{transform:rotate(180deg);color:var(--brand)}
.acc__panel{max-height:0;overflow:hidden;transition:max-height .3s ease}
.acc__inner{padding:0 22px 22px 82px}
.acc__intro{font-weight:600;color:var(--ink);margin-bottom:12px}
.acc__inner ul{margin:0 0 14px;padding-left:20px}
.acc__inner li{margin-bottom:8px;color:var(--text);font-size:15.5px}
.acc__gain{background:var(--brand-soft);border-radius:10px;padding:12px 16px;font-size:15px;color:var(--ink)}
.acc__gain b{color:var(--brand-dark)}
.note-box{max-width:900px;margin:22px auto 0;background:#F3F4F7;border:1px solid var(--line);
  border-left:3px solid var(--graphite);border-radius:8px;padding:14px 18px;color:var(--muted);
  font-size:14.5px}

/* ---------- Dòng thời gian nội dung học (6 buổi + Dự án tốt nghiệp liền mạch) ---------- */
.timeline{max-width:920px;margin:0 auto;position:relative}
.tl-item{display:grid;grid-template-columns:64px 1fr;gap:20px;position:relative;padding-bottom:24px}
.tl-item:last-child{padding-bottom:0}
.tl-rail{position:relative;display:flex;justify-content:center}
.tl-rail::before{content:"";position:absolute;top:6px;bottom:-24px;left:50%;transform:translateX(-50%);
  width:2px;background:linear-gradient(#F26522,#f4a06f);z-index:0}
.tl-item:last-child .tl-rail::before{display:none}
.tl-node{position:relative;z-index:1;width:56px;height:56px;border-radius:50%;background:var(--ink);color:#fff;
  display:flex;flex-direction:column;align-items:center;justify-content:center;line-height:1;flex:none;
  box-shadow:0 6px 14px rgba(0,0,0,.18);border:3px solid #fff}
.tl-node b{font-weight:600;font-size:10px;letter-spacing:.03em;opacity:.9;text-transform:uppercase}
.tl-node>span{font-weight:800;font-size:20px;margin-top:1px}
.tl-node--star{background:var(--brand);font-size:26px;align-items:center;justify-content:center}
.tl-card{background:#fff;border:1px solid var(--line);border-radius:14px;box-shadow:var(--shadow);padding:22px 24px}
.tl-title{font-size:16.5px;font-weight:800;color:var(--ink);margin:0 0 12px;line-height:1.35}
.tl-intro{font-weight:600;color:var(--ink);margin:0 0 12px}
.tl-card ul{margin:0 0 14px;padding-left:20px}
.tl-card li{margin-bottom:8px;color:var(--text);font-size:15.5px}
.tl-gain{background:var(--brand-soft);border-radius:10px;padding:12px 16px;font-size:15px;color:var(--ink)}
.tl-gain b{color:var(--brand-dark)}
/* Điểm kết: Dự án tốt nghiệp */
.tl-card--capstone{background:linear-gradient(160deg,#1b1f27,#2a2f3a);border:none;color:#EAECEF;box-shadow:var(--shadow-lg)}
.tl-card--capstone .tl-title{color:#fff;font-size:20px}
.tl-card--capstone li{color:#D4D8E0}
.tl-card--capstone p{color:#D4D8E0}
.tl-card--capstone .src{color:#9aa1ad;font-style:italic;font-size:14px;margin:0 0 14px}
.tl-badge{display:inline-block;background:rgba(242,101,34,.16);border:1px solid rgba(242,101,34,.5);
  color:#F26522;font-weight:700;font-size:12px;letter-spacing:.05em;text-transform:uppercase;
  padding:5px 12px;border-radius:999px;margin-bottom:12px}
.tl-gain--strong{background:rgba(242,101,34,.14);border:1px solid rgba(242,101,34,.4);color:#fff}
.tl-gain--strong b{color:#fff}
@media (max-width:600px){
  .tl-item{grid-template-columns:46px 1fr;gap:12px;padding-bottom:20px}
  .tl-node{width:46px;height:46px;border-width:2px}
  .tl-node b{font-size:8px}
  .tl-node>span{font-size:16px}
  .tl-node--star{font-size:22px}
  .tl-card{padding:18px 16px}
  .tl-title{font-size:15.5px}
}

/* ---------- Graduation (Khối 8) ---------- */
.grad{background:linear-gradient(160deg,#1b1f27,#2a2f3a);color:#EAECEF;border-radius:var(--radius);
  padding:44px;box-shadow:var(--shadow-lg)}
.grad h3{color:#fff;font-size:24px}
.grad .src{color:#9aa1ad;font-style:italic;font-size:14px;margin-bottom:16px}
.grad ul{padding-left:20px;margin:16px 0}
.grad li{margin-bottom:10px;color:#D4D8E0}
.grad__gain{margin-top:20px;background:rgba(242,101,34,.14);border:1px solid rgba(242,101,34,.4);
  border-radius:12px;padding:16px 20px;color:#fff}
.grad .btn-row{margin-top:26px}

/* ---------- Format & benefits (Khối 9) ---------- */
.benefits{display:grid;grid-template-columns:repeat(2,1fr);gap:14px}
.benefit{display:flex;gap:14px;background:#fff;border:1px solid var(--line);border-radius:var(--radius-sm);
  padding:18px 20px;box-shadow:var(--shadow)}
.benefit .chk{flex:none;width:26px;height:26px;border-radius:50%;background:var(--ok);color:#fff;
  display:grid;place-items:center;font-weight:800;margin-top:2px}
.benefit p{margin:0;font-size:15.5px}

/* ---------- Instructor (Khối 10) ---------- */
.teacher{display:grid;grid-template-columns:.8fr 1.2fr;gap:44px;align-items:center}
.teacher__media{position:relative}
.teacher__photo{border-radius:var(--radius);box-shadow:var(--shadow-lg);width:100%;max-width:400px;margin:0 auto}
.teacher__book{position:absolute;right:-6px;bottom:-18px;width:120px;border-radius:8px;
  box-shadow:var(--shadow-lg);border:3px solid #fff}
.teacher__book.ph{width:120px;height:180px;min-height:0;right:-6px;bottom:-18px;padding:8px;font-size:11px}
.teacher p{color:var(--text)}
.teacher .book-line{margin-top:14px;font-weight:700;color:var(--brand-dark)}

/* ---------- Pricing & form (Khối 13) — làm nổi bật khu vực chốt sale ---------- */
.pricing-wrap{
  position:relative;
  background:linear-gradient(160deg,#FFE4CC 0%,#FFF3E8 45%,#FFF 85%);
  border-radius:28px;
  padding:44px clamp(16px,4vw,44px) 40px;
  border:1px solid #FBC896;
  box-shadow:0 40px 80px -30px rgba(242,101,34,.35);
  overflow:hidden;
}
.pricing-wrap::before{
  content:"";position:absolute;top:-140px;right:-140px;width:380px;height:380px;border-radius:50%;
  background:radial-gradient(circle,rgba(242,101,34,.35),transparent 70%);pointer-events:none;
}
.pricing-wrap::after{
  content:"";position:absolute;bottom:-160px;left:-120px;width:340px;height:340px;border-radius:50%;
  background:radial-gradient(circle,rgba(217,84,26,.22),transparent 70%);pointer-events:none;
}
.pricing-badge-row{display:flex;justify-content:center;margin-bottom:6px}
.pricing-urgency{
  display:inline-flex;align-items:center;gap:8px;
  background:linear-gradient(135deg,var(--ink),#2A1810);color:#fff;
  font-size:13px;font-weight:700;padding:9px 20px;border-radius:999px;margin:0 auto 18px;
  box-shadow:0 10px 24px -8px rgba(0,0,0,.4);
  border:1px solid rgba(255,255,255,.08);
}
.pricing-urgency b{color:#FFB27A}
.pricing{display:grid;grid-template-columns:1.05fr 1fr;gap:28px;align-items:stretch;position:relative;z-index:1}

.price-card{
  position:relative;background:#fff;border-radius:var(--radius);
  padding:38px 32px 32px;
  box-shadow:0 25px 55px -18px rgba(242,101,34,.5);
  display:flex;flex-direction:column;
  border:3px solid transparent;
  background-image:linear-gradient(#fff,#fff),linear-gradient(135deg,var(--brand) 0%,#FFB300 100%);
  background-origin:border-box;background-clip:padding-box, border-box;
}
.price-card__ribbon{
  position:absolute;top:-16px;left:28px;
  background:linear-gradient(135deg,#FF7A1A,#E5484D);color:#fff;font-weight:800;
  font-size:12.5px;letter-spacing:.03em;padding:8px 18px;border-radius:999px;
  box-shadow:0 10px 20px -4px rgba(229,72,77,.55);
}
.price__list{color:var(--muted);text-decoration:line-through;font-size:19px;margin:14px 0 0}
.price__now{
  font-size:52px;font-weight:800;margin:2px 0 4px;letter-spacing:-.01em;
  background:linear-gradient(135deg,var(--brand) 20%,#FF3D3D 100%);
  -webkit-background-clip:text;background-clip:text;color:transparent;
}
.price__per-session{color:var(--muted);font-size:13.5px;margin:0 0 14px}
.price__save{
  display:inline-flex;align-items:center;gap:6px;
  background:linear-gradient(135deg,#FFD166,#FFB300);color:#5A3400;
  font-weight:800;border-radius:999px;padding:8px 18px;font-size:14px;margin-bottom:6px;
  box-shadow:0 8px 18px -6px rgba(255,179,0,.5);
}
.price__start{
  display:flex;align-items:center;gap:8px;margin-top:16px;padding-top:16px;border-top:1px dashed var(--line);
  font-size:14px;color:var(--ink);font-weight:600;
}
.price__start .dot{width:8px;height:8px;border-radius:50%;background:var(--ok);flex:none;box-shadow:0 0 0 4px rgba(31,157,85,.16)}
.price__benefits{list-style:none;padding:0;margin:20px 0 0}
.price__benefits li{position:relative;padding-left:30px;margin-bottom:12px;font-size:15.5px;line-height:1.45}
.price__benefits li::before{
  content:"✓";position:absolute;left:0;top:0;width:20px;height:20px;border-radius:50%;
  background:linear-gradient(135deg,#1f9d55,#17c96a);color:#fff;font-size:12px;font-weight:800;
  display:flex;align-items:center;justify-content:center;
  box-shadow:0 4px 10px -3px rgba(31,157,85,.5);
}
.price-card__foot{margin-top:auto;padding-top:22px}
.price-card__cta{margin-top:6px}

.form-card{
  background:#fff;border-radius:var(--radius);
  box-shadow:0 25px 55px -18px rgba(20,24,33,.28);position:relative;overflow:hidden;
  border:1px solid #FBC896;
}
.form-card__head{
  background:linear-gradient(135deg,var(--brand),#FF8A3D);
  padding:22px 32px;color:#fff;
}
.form-card__head h3{margin:0 0 4px;font-size:21px;color:#fff}
.form-card__sub{color:rgba(255,255,255,.92);font-size:14px;margin:0}
.form-card__body{padding:28px 32px 32px}
.field{margin-bottom:16px}
.field label{display:block;font-weight:600;font-size:14.5px;margin-bottom:6px;color:var(--ink)}
.field input{width:100%;padding:13px 15px;border:1.5px solid var(--line);border-radius:10px;
  background:var(--bg-soft);font-family:inherit;font-size:15.5px;transition:border .15s,background .15s}
.field input:focus{outline:none;border-color:var(--brand);background:#fff}
.field input.field-input--error{border-color:#E5484D;background:#FEF4F4}
.field-error{display:none;color:#E5484D;font-size:12.5px;margin-top:5px}
.field-error.show{display:block}
.consent{display:flex;gap:10px;align-items:flex-start;font-size:13.5px;color:var(--muted);margin-bottom:18px}
.consent input{margin-top:3px;flex:none;width:18px;height:18px;accent-color:var(--brand)}
.form-msg{margin-top:14px;padding:13px 16px;border-radius:10px;font-size:14.5px;display:none}
.form-msg.show{display:block}
.form-msg--ok{background:#E9F8EF;color:#1c7a43;border:1px solid #b7e6c8}
.form-msg--warn{background:#FFF7E6;color:#B7791F;border:1px solid #F5D48A}

.btn-row .btn--primary.btn--block{
  font-size:17px;padding:17px 20px;font-weight:800;
  background:linear-gradient(135deg,#FF7A1A,#E5484D);
  box-shadow:0 18px 34px -10px rgba(229,72,77,.55);
}
.btn-row .btn--primary.btn--block:hover{transform:translateY(-2px)}

@media (max-width:760px){
  .pricing-wrap{padding:30px 16px 28px;border-radius:20px}
  .price-card{padding:30px 22px 26px}
  .form-card__head{padding:20px 22px}
  .form-card__body{padding:24px 22px 26px}
  .price__now{font-size:42px}
}

/* ---------- FAQ (Khối 14) ---------- */
.faq{max-width:840px;margin:0 auto}
.faq__item{border-bottom:1px solid var(--line)}
.faq__q{width:100%;text-align:left;background:none;border:none;cursor:pointer;font-family:inherit;
  font-weight:700;font-size:16.5px;color:var(--ink);padding:20px 40px 20px 0;position:relative}
.faq__q::after{content:"+";position:absolute;right:6px;top:50%;transform:translateY(-50%);
  font-size:24px;color:var(--brand);font-weight:400;transition:.2s}
.faq__item.is-open .faq__q::after{content:"–"}
.faq__a{max-height:0;overflow:hidden;transition:max-height .28s ease;color:var(--muted)}
.faq__a p{padding:0 0 20px;margin:0}

/* ---------- Final CTA (Khối 15) ---------- */
.final{background:
  radial-gradient(900px 400px at 50% -20%,rgba(242,101,34,.25),transparent 60%),
  linear-gradient(160deg,#14161B,#232833);color:#fff;text-align:center;padding:80px 0}
.final h2{color:#fff}
.final .contact{display:flex;gap:26px;justify-content:center;flex-wrap:wrap;margin:22px 0 28px;
  font-size:18px;color:#D4D8E0}
.final .contact b{color:#fff}
.final .contact a{color:var(--brand);font-weight:700}

/* ---------- Footer ---------- */
.footer{background:#0F1115;color:#9aa1ad;padding:40px 0;font-size:14.5px}
.footer strong{color:#fff;font-size:16px;display:block;margin-bottom:10px}
.footer .op{margin-top:12px;color:#727884}

/* ---------- Placeholder (ảnh chưa có) ---------- */
.ph{display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;
  background:repeating-linear-gradient(45deg,#F1F2F5,#F1F2F5 12px,#ECEEF1 12px,#ECEEF1 24px);
  border:1px dashed #C4C9D2;border-radius:12px;color:#8a909b;padding:22px;min-height:150px;gap:4px}
.ph__code{font-weight:800;color:#6b7280;font-size:14px;letter-spacing:.04em}
.ph__type{font-size:13px}
.ph__spec{font-size:12px;color:#a2a8b3}
.section--ink .ph{background:repeating-linear-gradient(45deg,#20242e,#20242e 12px,#252a35 12px,#252a35 24px);
  border-color:#3a3f4b;color:#7f8794}
.ph--16x9{aspect-ratio:16/9;min-height:0}
.ph--2x3{aspect-ratio:2/3;min-height:0}
/* Product screenshots gallery (IMG-04..06) */
.shots{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:26px}
.shot-cap{text-align:center;color:var(--muted);font-size:14px;margin-top:10px;font-style:italic}
@media (max-width:760px){.shots{grid-template-columns:1fr}}
/* Illustration band (IMG-03) */
.illus{max-width:900px;margin:26px auto 0}
.illus .ph{min-height:0;aspect-ratio:16/9}

/* ---------- Mobile sticky CTA bar ---------- */
.mcta{position:fixed;left:0;right:0;bottom:0;z-index:60;display:none;gap:10px;padding:10px 14px;
  background:rgba(255,255,255,.97);backdrop-filter:blur(8px);border-top:1px solid var(--line);
  box-shadow:0 -6px 20px rgba(0,0,0,.08)}
.mcta .btn{flex:1;padding:13px 10px;font-size:15px}

/* ---------- Reveal on scroll ---------- */
.reveal{opacity:1;transform:none}
html.js .reveal{opacity:0;transform:translateY(18px);transition:opacity .5s ease,transform .5s ease}
html.js .reveal.in{opacity:1;transform:none}
.reveal.in{opacity:1;transform:none}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width:900px){
  .hero__grid{grid-template-columns:1fr;gap:10px;padding:44px 0 36px}
  .hero__media{order:-1;margin-bottom:6px}
  .hero__portrait{max-width:300px}
  .logo-grid{grid-template-columns:repeat(3,1fr)}
  .cards3,.aud-grid{grid-template-columns:1fr}
  .teacher{grid-template-columns:1fr;gap:24px}
  .teacher__media{max-width:340px;margin:0 auto}
  .pricing{grid-template-columns:1fr}
  .grad{padding:30px 24px}
}
@media (max-width:760px){
  body{font-size:16px}
  .section{padding:24px 0}
  .prob-grid,.benefits{grid-template-columns:1fr}
  .ba{grid-template-columns:1fr}
  .ba__col--before{border-bottom:2px solid var(--line)}
  .acc__inner{padding-left:22px}
  .mcta{display:flex}
  body{padding-bottom:74px}
  .final .contact{flex-direction:column;gap:10px}
}
@media (max-width:420px){
  .btn-row .btn{width:100%}
  .price__now{font-size:36px}
}
.promo-banner{
    display:flex;
    align-items:center;
    gap:16px;
    max-width:760px;
    width:100%;
    margin: 0px auto 0; 
    background:linear-gradient(135deg,#4A1C14 0%,#33110C 100%);
    border-radius:14px;
    padding:12px 16px;
    box-shadow:0 8px 20px -8px rgba(0,0,0,.4);
     
  }

  /* ---- Ảnh bìa sách ---- */
  .promo-cover{
    flex:none;
    width:64px;
    height:84px;
    border-radius:8px;
    overflow:hidden;
    position:relative;
    background:#FFF6E9;
    box-shadow:0 4px 10px -3px rgba(0,0,0,.5);
  }
  .promo-cover .rays{
    position:absolute;inset:0;
    background:
      repeating-conic-gradient(from 0deg,
        rgba(255,138,61,0.9) 0deg 6deg,
        rgba(255,196,120,0.55) 6deg 12deg);
    -webkit-mask-image:radial-gradient(circle at 50% 30%, #000 55%, transparent 75%);
            mask-image:radial-gradient(circle at 50% 30%, #000 55%, transparent 75%);
  }
  .promo-cover .brand{
    position:relative;z-index:1;
    text-align:center;
    padding-top:12px;
  }
  .promo-cover .brand .word{
    font-size:11px;font-weight:800;
    background:linear-gradient(90deg,#E23B2E,#FF7A3D);
    -webkit-background-clip:text;background-clip:text;color:transparent;
    letter-spacing:.01em;
  }
  .promo-cover .brand .sub{
    font-size:6.5px;font-weight:800;color:#17223B;
    letter-spacing:.09em;margin-top:2px;
  }
  .promo-cover .base{
    position:absolute;left:0;right:0;bottom:0;height:34%;
    background:#FBF3E7;
  }

  /* ---- Nội dung giữa ---- */
  .promo-body{flex:1;min-width:0;}
  .promo-title{
    color:#fff;
    font-size:15.5px;
    font-weight:700;
    line-height:1.3;
    margin:0 0 8px;
  }
  @media (max-width:560px){ .promo-title{font-size:13.5px;} }

  .promo-price-row{
    display:flex;
    align-items:center;
    gap:10px;
    flex-wrap:wrap;
  }
  .promo-price{
    color:#fff;
    font-size:17px;
    font-weight:800;
  }
  .promo-price-old{
    color:#B79C93;
    font-size:14px;
    font-weight: 700;
    text-decoration:line-through;
  }
  .promo-save{
    background:linear-gradient(135deg,#F5B942,#E8912B);
    color:#3A1B05;
    font-size:11px;
    font-weight:700;
    padding:4px 10px;
    border-radius:100px;
    white-space:nowrap;
  }

  /* ---- Nút CTA ---- */
  .promo-cta{
    flex:none;
    background:linear-gradient(135deg,#FF8A3D,#F0641B);
    color:#fff;
    font-weight:700;
    font-size:14px;
    padding:12px 22px;
    border-radius:100px;
    border:none;
    cursor:pointer;
    white-space:nowrap;
    box-shadow:0 6px 14px -4px rgba(240,100,27,.6);
    transition:transform .15s ease;
  }
  .promo-cta:hover{transform:translateY(-1px);}

  @media (max-width:480px){
    .promo-banner{ position:fixed; bottom:0;flex-direction:column; align-items:stretch; gap:10px;}
    .promo-cta{width:100%;text-align:center;}
  }
  @media (max-width:760px){
  .promo-banner{
    /* position:fixed;left:0;right:0;bottom:69px;z-index:59;  ← dính sticky lên trên thanh CTA */
    max-width:none;width:100%;margin:0;
    /* height:auto;min-height:0;top:auto; */
    border-radius:0;box-shadow:0 -4px 16px rgba(0,0,0,.35);
  }
  .footer{
    margin-bottom: 0px;
  }
}