/* ------------------------------------------------------------------
   Tốc Biến — bản dựng lại nhắm người làm app bằng AI.
   Giữ nhận diện gốc: nền gần đen, xanh điện, tia chớp.
   Ngôn ngữ thị giác: công cụ dev — lưới mờ, chữ mono, khối lệnh thật.
   ------------------------------------------------------------------ */

:root {
  --bg:        #050507;
  --bg-2:      #0A0C10;
  --surface:   #0F1217;
  --surface-2: #14181F;
  --border:    #1C222B;
  --border-2:  #2A323E;
  --fg:        #F2F5F9;
  --muted:     #98A2B3;   /* 7.9:1 trên nền — đạt AA thoải mái */
  --accent:    #38BDF8;   /* xanh điện của thương hiệu, 9.5:1 */
  --accent-d:  #0EA5E9;
  --ok:        #34D399;   /* trạng thái đã chạy, 10.6:1 */
  --warn:      #FBBF24;

  --sans: "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono: "JetBrains Mono", ui-monospace, "Cascadia Mono", Consolas, monospace;

  --r:   10px;
  --r-s: 6px;
  --ease: cubic-bezier(.2, .6, .2, 1);
  --t: 160ms;

  --container: 1120px;
  --gutter: 20px;
}

@media (min-width: 768px)  { :root { --gutter: 32px; } }
@media (min-width: 1140px) { :root { --gutter: 40px; } }

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 1rem;
  line-height: 1.65;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
@media (min-width: 768px) { body { font-size: 1.0625rem; } }

/* Lưới mờ phía sau, chất công cụ dev */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background-image:
    linear-gradient(to right,  rgba(255,255,255,.028) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255,255,255,.028) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 100% 60% at 50% 0%, #000 35%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 100% 60% at 50% 0%, #000 35%, transparent 78%);
}
body > * { position: relative; z-index: 1; }

img, svg { max-width: 100%; }

/* ---------- Khung ---------- */

.wrap {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.sec { padding-block: 72px; }
@media (min-width: 768px)  { .sec { padding-block: 104px; } }
@media (min-width: 1140px) { .sec { padding-block: 120px; } }
.sec--vien { border-top: 1px solid var(--border); }

/* ---------- Chữ ---------- */

h1, h2, h3, h4 { margin: 0; font-weight: 700; letter-spacing: -0.02em; line-height: 1.2; }

.nhan {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--mono);
  font-size: 0.6875rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  color: var(--muted);
  margin-bottom: 18px;
}
.nhan::before {
  content: "";
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 3px rgba(56,189,248,.16);
  flex: none;
}

.h2 {
  font-size: clamp(1.75rem, 4.2vw, 2.75rem);
  letter-spacing: -0.03em;
  line-height: 1.16;
  /* dấu tiếng Việt cần chỗ thở */
  padding-top: .04em;
}

.dan {
  color: var(--muted);
  font-size: 1.0625rem;
  line-height: 1.7;
  max-width: 62ch;
  margin: 16px 0 0;
}

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

code, .mono { font-family: var(--mono); }

/* ---------- Nút ---------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 46px;
  padding: 12px 20px;
  border-radius: var(--r-s);
  border: 1px solid transparent;
  font-family: var(--sans);
  font-size: 0.9375rem;
  font-weight: 600;
  line-height: 1.2;
  text-decoration: none;
  cursor: pointer;
  white-space: nowrap;
  transition: background-color var(--t) var(--ease), border-color var(--t) var(--ease),
              color var(--t) var(--ease), transform var(--t) var(--ease);
}
.btn:active { transform: translateY(1px); }
.btn:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.btn--chinh {
  background: var(--accent);
  color: #04222F;
  box-shadow: 0 0 0 1px rgba(56,189,248,.35), 0 10px 30px -12px rgba(56,189,248,.55);
}
.btn--chinh:hover { background: #5CCBFA; }

.btn--phu {
  background: var(--surface);
  color: var(--fg);
  border-color: var(--border-2);
}
.btn--phu:hover { background: var(--surface-2); border-color: #3A4452; }

.btn--nho { min-height: 44px; padding: 10px 15px; font-size: 0.875rem; }

.lk {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(56,189,248,.35);
  transition: border-color var(--t) var(--ease);
}
.lk:hover { border-bottom-color: var(--accent); }
.lk:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

/* ---------- Thanh trên ---------- */

.top {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(5,5,7,.82);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.top__in {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: 62px;
}
.hieu {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  color: var(--fg);
  text-decoration: none;
  font-weight: 700;
  letter-spacing: 0.02em;
  font-size: 1.0625rem;
}
.hieu:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }
.hieu svg { width: 22px; height: 22px; flex: none; }
.top__nut { display: flex; align-items: center; gap: 10px; }
@media (max-width: 559px) { .top__nut .btn--phu { display: none; } }

/* ---------- Mở đầu ---------- */

.hero { padding-block: 64px 56px; }
@media (min-width: 900px) { .hero { padding-block: 104px 88px; } }

.hero__luoi { display: grid; gap: 48px; }
@media (min-width: 1000px) {
  .hero__luoi { grid-template-columns: 1.05fr .95fr; gap: 56px; align-items: center; }
}

.hero h1 {
  font-size: clamp(2.125rem, 6vw, 3.75rem);
  line-height: 1.12;
  letter-spacing: -0.035em;
  padding-top: .05em;
}
.hero h1 .ma {
  display: inline-block;
  font-family: var(--mono);
  font-weight: 600;
  font-size: .88em;
  color: var(--accent);
  background: rgba(56,189,248,.08);
  border: 1px solid rgba(56,189,248,.24);
  border-radius: var(--r-s);
  padding: .04em .22em;
  letter-spacing: -0.02em;
}
.hero h1 .d2 { display: block; margin-top: .18em; }

.hero__dan { margin-top: 24px; font-size: 1.0625rem; }
@media (min-width: 768px) { .hero__dan { font-size: 1.125rem; } }

.hero__nut { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }

.hero__tin {
  display: flex; flex-wrap: wrap; gap: 8px 20px;
  margin-top: 28px; padding-top: 22px;
  border-top: 1px solid var(--border);
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
}
.hero__tin span { display: inline-flex; align-items: center; gap: 7px; }
.hero__tin span::before {
  content: ""; width: 5px; height: 5px; border-radius: 50%;
  background: var(--ok); flex: none;
}

/* ---------- Cửa sổ lệnh ---------- */

.term {
  background: var(--surface);
  border: 1px solid var(--border-2);
  border-radius: var(--r);
  overflow: hidden;
  box-shadow: 0 30px 70px -30px rgba(0,0,0,.9);
}
.term__bar {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 14px;
  background: var(--surface-2);
  border-bottom: 1px solid var(--border);
}
.term__cham { display: flex; gap: 6px; }
.term__cham i { width: 10px; height: 10px; border-radius: 50%; background: #2C333D; display: block; }
.term__ten {
  font-family: var(--mono); font-size: 0.6875rem; color: var(--muted);
  letter-spacing: .06em; margin-left: 4px;
}
.term__lai {
  margin-left: auto;
  background: none; border: 1px solid var(--border-2); border-radius: var(--r-s);
  color: var(--muted); font-family: var(--mono); font-size: 0.6875rem;
  padding: 7px 12px; min-height: 44px; cursor: pointer;
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease);
}
.term__lai:hover { color: var(--fg); border-color: #3A4452; }
.term__lai:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.term__than {
  padding: 18px 16px 20px;
  font-family: var(--mono);
  font-size: 0.8125rem;
  line-height: 1.95;
}
@media (min-width: 420px) { .term__than { padding: 20px; font-size: 0.875rem; } }

.term__dong { display: block; white-space: pre-wrap; word-break: break-word; }
.js .term__dong[data-an="1"] { visibility: hidden; }
.term__dong .u { color: var(--accent); }
.term__dong .nd { color: var(--fg); }
.term__dong .b { color: var(--muted); }
.term__dong .k { color: var(--ok); }
.term__dong .x { color: var(--ok); font-weight: 600; }
.term__dong .x a { color: var(--ok); text-decoration: none; border-bottom: 1px solid rgba(52,211,153,.4); }
.term__dong .x a:hover { border-bottom-color: var(--ok); }
.term__dong .x a:focus-visible { outline: 2px solid var(--ok); outline-offset: 2px; }

.term__con {
  display: inline-block; width: 8px; height: 1em;
  background: var(--accent); vertical-align: -2px;
  animation: nhay 1.05s steps(2, start) infinite;
}
@keyframes nhay { 0%,100% { opacity: 1 } 50% { opacity: 0 } }
@media (prefers-reduced-motion: reduce) { .term__con { animation: none; } }

.term__chu {
  margin: 12px 2px 0;
  font-family: var(--mono);
  font-size: 0.6875rem;
  line-height: 1.6;
  color: var(--muted);
}

/* ---------- Vấn đề ---------- */

.vd { display: grid; gap: 1px; margin-top: 48px; background: var(--border); border: 1px solid var(--border); border-radius: var(--r); overflow: hidden; }
@media (min-width: 900px) { .vd { grid-template-columns: repeat(3, 1fr); } }
.vd__o { background: var(--bg-2); padding: 28px 24px 30px; transition: background-color var(--t) var(--ease); }
.vd__o:hover { background: var(--surface); }
.vd__so { font-family: var(--mono); font-size: 0.75rem; letter-spacing: .16em; color: var(--accent); }
.vd__ten { font-size: 1.1875rem; margin: 14px 0 10px; letter-spacing: -0.02em; line-height: 1.32; }
.vd__mt { color: var(--muted); font-size: 0.9375rem; line-height: 1.7; margin: 0; }

/* ---------- Không gian AI cần ---------- */

.kg__chay {
  display: grid;
  gap: 10px;
  margin-top: 44px;
}
@media (min-width: 900px) {
  .kg__chay { grid-auto-flow: column; grid-auto-columns: 1fr; align-items: stretch; gap: 0; }
}

.kg__nut {
  position: relative;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--r);
  padding: 20px 18px;
}
@media (min-width: 900px) {
  .kg__nut { border-radius: 0; border-left-width: 0; }
  .kg__nut:first-child { border-left-width: 1px; border-radius: var(--r) 0 0 var(--r); }
  .kg__nut:last-child  { border-radius: 0 var(--r) var(--r) 0; }
}

/* Mũi tên nối giữa các chặng */
.kg__nut + .kg__nut::before {
  content: "";
  position: absolute;
  left: 50%; top: -10px;
  width: 1px; height: 10px;
  background: var(--border-2);
}
@media (min-width: 900px) {
  .kg__nut + .kg__nut::before {
    left: -1px; top: 0; bottom: 0;
    width: 1px; height: auto;
  }
}

.kg__nut--manh {
  background: linear-gradient(180deg, rgba(56,189,248,.1), rgba(56,189,248,.02));
  border-color: rgba(56,189,248,.45);
  z-index: 1;
}
@media (min-width: 900px) {
  .kg__nut--manh { border-left-width: 1px; border-radius: var(--r); }
}

.kg__ten { display: flex; align-items: center; gap: 8px; font-size: 1rem; font-weight: 600; margin: 0; letter-spacing: -0.01em; }
.kg__nut--manh .kg__ten { color: var(--accent); }
.kg__ten svg { width: 15px; height: 15px; flex: none; }
.kg__mo { color: var(--muted); font-size: 0.8125rem; line-height: 1.6; margin: 7px 0 0; }

.kg__cot { display: grid; gap: 1px; margin-top: 24px; background: var(--border); border: 1px solid var(--border); border-radius: var(--r); overflow: hidden; }
@media (min-width: 680px)  { .kg__cot { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1060px) { .kg__cot { grid-template-columns: repeat(4, 1fr); } }
.kg__o { background: var(--bg-2); padding: 24px 22px 26px; transition: background-color var(--t) var(--ease); }
.kg__o:hover { background: var(--surface); }
.kg__oTen {
  display: flex; align-items: center; gap: 9px;
  font-size: 1rem; font-weight: 600; margin: 0 0 10px; letter-spacing: -0.01em;
}
.kg__oTen i {
  width: 24px; height: 24px; flex: none;
  display: grid; place-items: center;
  border-radius: var(--r-s);
  background: rgba(56,189,248,.1);
  border: 1px solid rgba(56,189,248,.3);
  color: var(--accent);
  font-family: var(--mono); font-size: 0.625rem; font-style: normal; font-weight: 500;
}
.kg__oMt { color: var(--muted); font-size: 0.875rem; line-height: 1.7; margin: 0; }

/* ---------- Ba bước ---------- */

.bb { display: grid; gap: 20px; margin-top: 48px; }
@media (min-width: 940px) { .bb { grid-template-columns: repeat(3, 1fr); gap: 24px; } }

.bb__o {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--r);
  padding: 26px 22px;
  display: flex; flex-direction: column;
  /* Không có dòng này thì khối lệnh bên trong đẩy thẻ rộng hơn màn hình */
  min-width: 0;
  transition: border-color var(--t) var(--ease);
}
.bb__o:hover { border-color: var(--border-2); }
.bb__so {
  width: 34px; height: 34px; flex: none;
  display: grid; place-items: center;
  border: 1px solid rgba(56,189,248,.3);
  background: rgba(56,189,248,.08);
  border-radius: var(--r-s);
  font-family: var(--mono); font-size: 0.75rem; font-weight: 500; color: var(--accent);
}
.bb__ten { font-size: 1.125rem; margin: 18px 0 10px; letter-spacing: -0.02em; line-height: 1.35; }
.bb__mt { color: var(--muted); font-size: 0.9375rem; line-height: 1.7; margin: 0 0 20px; }

.ma {
  margin-top: auto;
  background: #07090C;
  border: 1px solid var(--border);
  border-radius: var(--r-s);
  overflow: hidden;
  min-width: 0;
  max-width: 100%;
}
.ma__nhan {
  font-family: var(--mono); font-size: 0.625rem; letter-spacing: .12em;
  color: var(--muted); padding: 9px 12px;
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,.015);
  text-transform: uppercase;
}
.ma pre {
  margin: 0; padding: 13px 12px;
  font-family: var(--mono); font-size: 0.75rem; line-height: 1.75;
  color: #C4CDDA;
  overflow-x: auto;
  white-space: pre;
  max-width: 100%;
}
.ma pre::-webkit-scrollbar { height: 6px; }
.ma pre::-webkit-scrollbar-thumb { background: var(--border-2); border-radius: 3px; }

/* ---------- Máy thật ---------- */

.mt { display: grid; gap: 1px; margin-top: 48px; background: var(--border); border: 1px solid var(--border); border-radius: var(--r); overflow: hidden; }
@media (min-width: 640px) { .mt { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .mt { grid-template-columns: repeat(4, 1fr); } }
.mt__o { background: var(--bg-2); padding: 22px 20px 24px; transition: background-color var(--t) var(--ease); }
.mt__o:hover { background: var(--surface); }
.mt__ten { display: flex; align-items: center; gap: 9px; font-size: 0.9375rem; font-weight: 600; margin: 0 0 8px; }
.mt__ten::before {
  content: ""; width: 14px; height: 14px; flex: none; border-radius: 3px;
  background: rgba(52,211,153,.14);
  border: 1px solid rgba(52,211,153,.45);
}
.mt__mt { color: var(--muted); font-size: 0.8125rem; line-height: 1.65; margin: 0; }

/* ---------- Đồ nghề ---------- */

.dn__tab { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 40px; }
.dn__t {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--r-s); color: var(--muted);
  font-family: var(--sans); font-size: 0.875rem; font-weight: 600;
  padding: 11px 16px; min-height: 44px; cursor: pointer;
  transition: color var(--t) var(--ease), border-color var(--t) var(--ease), background-color var(--t) var(--ease);
}
.dn__t:hover { color: var(--fg); }
.dn__t[aria-selected="true"] {
  color: var(--accent);
  border-color: rgba(56,189,248,.45);
  background: rgba(56,189,248,.08);
}
.dn__t:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }

.dn__bang {
  margin-top: 20px;
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--r);
  padding: 26px 22px;
}
@media (min-width: 768px) { .dn__bang { padding: 32px 30px; } }
.dn__bang[hidden] { display: none; }
.dn__cong { display: flex; flex-wrap: wrap; gap: 8px; margin-bottom: 20px; }
.dn__cong span {
  font-family: var(--mono); font-size: 0.75rem;
  background: var(--surface-2); border: 1px solid var(--border-2);
  border-radius: 999px; padding: 6px 12px; color: var(--fg);
}
.dn__mt { color: var(--muted); font-size: 0.9375rem; line-height: 1.75; margin: 0 0 22px; max-width: 64ch; }
.dn__ds { list-style: none; margin: 0; padding: 0; display: grid; gap: 10px; }
@media (min-width: 700px) { .dn__ds { grid-template-columns: repeat(2, 1fr); gap: 10px 28px; } }
.dn__ds li {
  display: flex; align-items: flex-start; gap: 10px;
  font-size: 0.9375rem; color: var(--fg);
}
.dn__ds li::before {
  content: "✓"; color: var(--ok); font-family: var(--mono);
  font-size: 0.8125rem; line-height: 1.7; flex: none;
}
.dn__luu {
  margin: 22px 0 0; padding: 14px 16px;
  background: rgba(251,191,36,.06);
  border: 1px solid rgba(251,191,36,.28);
  border-radius: var(--r-s);
  color: #E8D5A8; font-size: 0.875rem; line-height: 1.65;
}

/* ---------- Dựng sẵn ---------- */

.ds { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 40px; }
.ds__o {
  flex: 1 1 200px;
  background: var(--bg-2); border: 1px solid var(--border);
  border-radius: var(--r); padding: 20px;
  transition: border-color var(--t) var(--ease);
}
.ds__o:hover { border-color: var(--border-2); }
.ds__ten { font-family: var(--mono); font-size: 0.9375rem; font-weight: 500; color: var(--accent); margin: 0 0 7px; }
.ds__mt { color: var(--muted); font-size: 0.8125rem; line-height: 1.6; margin: 0; }

/* ---------- Giá ---------- */

.gia__ky { display: inline-flex; flex-wrap: wrap; gap: 4px; margin-top: 36px; padding: 4px; background: var(--surface); border: 1px solid var(--border); border-radius: var(--r-s); }
.gia__k {
  background: none; border: 0; border-radius: 4px;
  color: var(--muted); font-family: var(--sans); font-size: 0.875rem; font-weight: 600;
  padding: 11px 15px; min-height: 44px; cursor: pointer; white-space: nowrap;
  transition: color var(--t) var(--ease), background-color var(--t) var(--ease);
}
.gia__k:hover { color: var(--fg); }
.gia__k[aria-pressed="true"] { background: var(--surface-2); color: var(--fg); box-shadow: inset 0 0 0 1px var(--border-2); }
.gia__k:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.gia__k small { color: var(--ok); font-weight: 500; margin-left: 5px; }

.gia__luoi { display: grid; gap: 16px; margin-top: 28px; }
@media (min-width: 620px)  { .gia__luoi { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1000px) { .gia__luoi { grid-template-columns: repeat(3, 1fr); } }

.goi {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--r);
  padding: 24px 22px;
  display: flex; flex-direction: column;
  transition: border-color var(--t) var(--ease);
}
.goi:hover { border-color: var(--border-2); }
.goi--nhan { border-color: rgba(56,189,248,.4); background: linear-gradient(180deg, rgba(56,189,248,.05), transparent 50%); }

.goi__dau { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.goi__ten { font-size: 1.125rem; letter-spacing: -0.01em; }
.goi__kho {
  font-family: var(--mono); font-size: 0.625rem; letter-spacing: .08em;
  padding: 4px 8px; border-radius: 999px; white-space: nowrap;
}
.goi__kho--ngay { color: var(--ok); background: rgba(52,211,153,.1); border: 1px solid rgba(52,211,153,.35); }
.goi__kho--cho  { color: var(--warn); background: rgba(251,191,36,.08); border: 1px solid rgba(251,191,36,.3); }
.goi__kho--het  { color: var(--muted); background: rgba(255,255,255,.03); border: 1px solid var(--border-2); }

.goi__ch { font-family: var(--mono); font-size: 0.8125rem; color: var(--muted); margin: 12px 0 0; }
.goi__hv { font-size: 0.875rem; color: var(--muted); margin: 10px 0 0; line-height: 1.6; }

.goi__gia { margin: 20px 0 0; display: flex; align-items: baseline; gap: 7px; flex-wrap: wrap; }
.goi__so { font-size: 1.75rem; font-weight: 700; letter-spacing: -0.03em; font-family: var(--mono); }
.goi__dv { font-size: 0.8125rem; color: var(--muted); }
.goi__truoc { font-size: 0.8125rem; color: var(--muted); text-decoration: line-through; }
.goi__tong { font-size: 0.75rem; color: var(--muted); font-family: var(--mono); margin: 6px 0 0; }
.goi .btn { margin-top: 20px; width: 100%; }

.thu {
  margin-top: 24px;
  background: linear-gradient(135deg, rgba(52,211,153,.07), rgba(56,189,248,.05));
  border: 1px solid rgba(52,211,153,.3);
  border-radius: var(--r);
  padding: 24px 22px;
  display: grid; gap: 18px;
}
@media (min-width: 800px) { .thu { grid-template-columns: 1fr auto; align-items: center; padding: 26px 28px; } }
.thu__ten { font-size: 1.125rem; margin: 0 0 8px; }
.thu__mt { color: var(--muted); font-size: 0.9375rem; margin: 0; line-height: 1.65; max-width: 62ch; }
.thu__gia { display: flex; align-items: baseline; gap: 9px; margin-top: 12px; }
.thu__so { font-family: var(--mono); font-size: 1.625rem; font-weight: 700; color: var(--ok); }
.thu__cu { font-family: var(--mono); font-size: 0.875rem; color: var(--muted); text-decoration: line-through; }
.thu__suat { font-family: var(--mono); font-size: 0.75rem; color: var(--muted); margin-top: 6px; }

.gia__chu { margin-top: 20px; font-size: 0.8125rem; color: var(--muted); line-height: 1.7; }
.gia__loi {
  margin-top: 24px; padding: 14px 16px;
  border: 1px solid rgba(251,191,36,.3); background: rgba(251,191,36,.06);
  border-radius: var(--r-s); color: #E8D5A8; font-size: 0.875rem;
}

/* ---------- Hỏi đáp ---------- */

.hd { margin-top: 44px; border-top: 1px solid var(--border); }
.hd__m { border-bottom: 1px solid var(--border); }
.hd__n {
  width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 20px;
  background: none; border: 0; border-radius: 0;
  padding: 22px 4px; min-height: 60px;
  color: var(--fg); font-family: var(--sans); font-size: 1.0625rem; font-weight: 600;
  text-align: left; cursor: pointer; letter-spacing: -0.01em; line-height: 1.4;
  transition: color var(--t) var(--ease);
}
.hd__n:hover { color: var(--accent); }
.hd__n:focus-visible { outline: 2px solid var(--accent); outline-offset: -2px; }
.hd__dau { flex: none; width: 18px; height: 18px; position: relative; }
.hd__dau::before, .hd__dau::after {
  content: ""; position: absolute; background: var(--muted);
  transition: transform var(--t) var(--ease), background-color var(--t) var(--ease);
}
.hd__dau::before { left: 0; right: 0; top: 8px; height: 2px; }
.hd__dau::after  { top: 0; bottom: 0; left: 8px; width: 2px; }
.hd__n[aria-expanded="true"] .hd__dau::after { transform: scaleY(0); }
.hd__n[aria-expanded="true"] .hd__dau::before { background: var(--accent); }
.hd__tl { padding: 0 4px 24px; color: var(--muted); font-size: 0.9375rem; line-height: 1.8; max-width: 76ch; }
.hd__tl[hidden] { display: none; }

/* ---------- Kết ---------- */

.ket {
  border: 1px solid var(--border-2);
  border-radius: 14px;
  background:
    radial-gradient(ellipse 70% 130% at 50% 0%, rgba(56,189,248,.13), transparent 62%),
    var(--bg-2);
  padding: 52px 24px 56px;
  text-align: center;
}
@media (min-width: 768px) { .ket { padding: 72px 40px 76px; } }
.ket h2 { font-size: clamp(1.625rem, 4.4vw, 2.5rem); letter-spacing: -0.03em; line-height: 1.18; padding-top: .04em; }
.ket p { color: var(--muted); margin: 14px auto 0; max-width: 46ch; }
.ket__nut { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; margin-top: 30px; }

/* ---------- Chân trang ---------- */

.chan { border-top: 1px solid var(--border); padding-block: 44px 36px; }
.chan__luoi { display: grid; gap: 30px; }
@media (min-width: 700px) { .chan__luoi { grid-template-columns: 1.6fr 1fr 1fr; gap: 40px; } }
.chan__mt { color: var(--muted); font-size: 0.875rem; margin: 14px 0 0; max-width: 42ch; line-height: 1.7; }
.chan h3 {
  font-family: var(--mono); font-size: 0.6875rem; font-weight: 500;
  letter-spacing: .16em; color: var(--muted); margin: 0 0 6px; text-transform: uppercase;
}
.chan ul { list-style: none; margin: 0; padding: 0; }
.chan a {
  display: inline-block; padding-block: 10px;
  color: var(--fg); text-decoration: none; font-size: 0.9375rem;
  transition: color var(--t) var(--ease);
}
.chan a:hover { color: var(--accent); }
.chan a:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.chan__cuoi {
  margin-top: 34px; padding-top: 22px; border-top: 1px solid var(--border);
  display: flex; flex-wrap: wrap; gap: 8px 18px; justify-content: space-between;
  font-size: 0.8125rem; color: var(--muted);
}
.chan__gc { font-family: var(--mono); font-size: 0.6875rem; line-height: 1.7; }

/* ---------- Hiện dần ---------- */

.js .len { opacity: 0; transform: translateY(16px); transition: opacity .55s var(--ease), transform .55s var(--ease); }
.js .len.ok { opacity: 1; transform: none; }

@media (prefers-reduced-motion: reduce) {
  .js .len { opacity: 1; transform: none; transition: none; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}

/* ---------- Phụ trợ ---------- */

.sr { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }

.bo-qua {
  position: absolute; left: 10px; top: -60px; z-index: 200;
  background: var(--accent); color: #04222F;
  padding: 11px 18px; border-radius: var(--r-s);
  font-size: 0.875rem; font-weight: 600; text-decoration: none;
  transition: top var(--t) var(--ease);
}
.bo-qua:focus { top: 10px; }