/* BizMind — trang giới thiệu. Màu lấy từ logo: xanh dương → xanh ngọc → tím. */

:root {
  --bg: #ffffff;
  --bg-soft: #f4f7fd;
  --card: #ffffff;
  --ink: #0b1430;
  --ink-2: #48526e;
  --ink-3: #7a839c;
  --line: #e1e7f3;
  --brand: #2456e8;
  --brand-ink: #1a43c4;
  --cyan: #12b5d6;
  --violet: #7346f0;
  --grad: linear-gradient(115deg, #2456e8 0%, #12a8d6 52%, #7346f0 100%);
  --ok: #129a4c;
  --ok-bg: #e5f7ec;
  --warn: #c77700;
  --warn-bg: #fff3df;
  --no: #cf3d3d;
  --no-bg: #fde9e9;
  --shadow-sm: 0 1px 2px rgb(11 20 48 / .05), 0 1px 3px rgb(11 20 48 / .05);
  --shadow: 0 12px 32px -12px rgb(16 36 94 / .18), 0 2px 6px rgb(16 36 94 / .05);
  --shadow-lg: 0 50px 90px -35px rgb(16 36 94 / .45);
  --radius: 18px;

  /* màu khung chat giống app BizMind (bảng màu kiểu Telegram, theme/tg.dart) */
  --tg-head: rgb(247 247 247 / .95);
  --tg-in: #ffffff;
  --tg-out: #e1ffc7;
  --tg-text: #000000;
  --tg-time-in: rgb(82 82 82 / .6);
  --tg-time-out: rgb(0 140 9 / .8);
  --tg-tick: #19c700;
  --tg-wall: linear-gradient(160deg, #dbddbb 0%, #88b884 38%, #6ba587 68%, #d5d88d 100%);
  --tg-pattern: rgb(31 59 31 / .18);
  --tg-list: #ffffff;
  --tg-sub: #8e8e93;
  --tg-sep: #e4e4e8;
  --tg-accent: #0088ff;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #070c1a;
    --bg-soft: #0b1224;
    --card: #101930;
    --ink: #e9edf8;
    --ink-2: #a9b2c9;
    --ink-3: #7d87a1;
    --line: #1e2944;
    --brand: #5b86ff;
    --brand-ink: #86a6ff;
    --ok: #3ccf7d;
    --ok-bg: rgb(60 207 125 / .12);
    --warn: #f0ad3c;
    --warn-bg: rgb(240 173 60 / .12);
    --no: #f07070;
    --no-bg: rgb(240 112 112 / .12);
    --shadow-sm: 0 1px 2px rgb(0 0 0 / .4);
    --shadow: 0 14px 34px -14px rgb(0 0 0 / .7);
    --shadow-lg: 0 50px 90px -35px rgb(0 0 0 / .9);

    --tg-head: rgb(36 45 57 / .95);
    --tg-in: #232e3b;
    --tg-out: #3e618a;
    --tg-text: #fafafa;
    --tg-time-in: rgb(128 145 160 / .85);
    --tg-time-out: rgb(190 215 240 / .8);
    --tg-tick: #8fd3ff;
    --tg-wall: linear-gradient(160deg, #1d2b26 0%, #213a33 45%, #18282f 100%);
    --tg-pattern: rgb(255 255 255 / .06);
    --tg-list: #1d2733;
    --tg-sub: #7d8b99;
    --tg-sep: #131a23;
    --tg-accent: #64b5ef;
    color-scheme: dark;
  }
}

/* ---------- nền tảng ---------- */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 400 17px/1.6 "Be Vietnam Pro", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
img { max-width: 100%; display: block; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-ink); }
h1, h2, h3 { margin: 0; line-height: 1.2; letter-spacing: -.02em; text-wrap: balance; }
h1 { font-size: clamp(2.1rem, 4.6vw, 3.5rem); font-weight: 800; }
h2 { font-size: clamp(1.7rem, 3.2vw, 2.5rem); font-weight: 800; }
h3 { font-size: 1.13rem; font-weight: 700; }
p { margin: 0; }
:focus-visible { outline: 3px solid var(--brand); outline-offset: 3px; border-radius: 6px; }
.sr-only { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

.ic {
  width: 1.25em; height: 1.25em; flex: none;
  fill: none; stroke: currentColor; stroke-width: 2; stroke-linecap: round; stroke-linejoin: round;
}

.container { width: 100%; max-width: 1180px; margin: 0 auto; padding: 0 24px; }
.container.narrow { max-width: 820px; }
@media (max-width: 600px) { .container { padding: 0 16px; } }

.grad-text {
  background: var(--grad);
  -webkit-background-clip: text; background-clip: text;
  color: transparent;
}

/* ---------- nút ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: .5em;
  border: 0; border-radius: 999px; cursor: pointer;
  font-family: inherit; font-size: 1rem; font-weight: 600; line-height: 1.2; text-align: center;
  padding: .85em 1.4em;
  transition: transform .15s ease, box-shadow .2s ease, background-color .2s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-primary {
  color: #fff; background: var(--grad); background-size: 140% 100%;
  box-shadow: 0 8px 22px -8px rgb(36 86 232 / .6);
}
.btn-primary:hover { color: #fff; box-shadow: 0 12px 28px -8px rgb(36 86 232 / .7); }
.btn-ghost { color: var(--ink); background: var(--card); box-shadow: inset 0 0 0 1.5px var(--line); }
.btn-ghost:hover { color: var(--ink); box-shadow: inset 0 0 0 1.5px var(--brand); }
.btn-sm { padding: .65em 1.1em; font-size: .93rem; }
.btn-lg { padding: 1em 1.6em; font-size: 1.04rem; }

/* ---------- đầu trang ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  backdrop-filter: saturate(1.6) blur(14px); -webkit-backdrop-filter: saturate(1.6) blur(14px);
  border-bottom: 1px solid transparent;
  transition: border-color .2s ease;
}
.site-header.scrolled { border-bottom-color: var(--line); }
.nav { display: flex; align-items: center; gap: 28px; height: 68px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 800; font-size: 1.2rem; letter-spacing: -.02em; }
.brand:hover { color: var(--ink); }
.brand img { border-radius: 9px; }
.nav-links { display: flex; gap: 26px; margin-left: auto; }
.nav-links a { color: var(--ink-2); font-weight: 500; font-size: .96rem; }
.nav-links a:hover { color: var(--ink); }
.nav-cta-mobile { display: none; }
.nav-toggle {
  display: none; margin-left: auto;
  width: 42px; height: 42px; border-radius: 12px; border: 1px solid var(--line);
  background: var(--card); color: var(--ink); cursor: pointer;
  align-items: center; justify-content: center;
}

@media (max-width: 900px) {
  .nav-cta { display: none; }
  .nav-toggle { display: inline-flex; }
  .nav-links {
    position: absolute; left: 0; right: 0; top: 68px;
    flex-direction: column; gap: 4px; padding: 12px 16px 18px;
    background: var(--bg); border-bottom: 1px solid var(--line); box-shadow: var(--shadow);
    display: none;
  }
  .nav-links.open { display: flex; }
  .nav-links a { padding: 10px 8px; font-size: 1.05rem; }
  .nav-links .nav-cta-mobile { display: inline-flex; margin-top: 8px; color: #fff; }
}

/* ---------- hero ---------- */
.hero { position: relative; padding: 72px 0 88px; overflow: hidden; }
.hero-bg {
  position: absolute; inset: -20% -10% 0; z-index: -1; pointer-events: none;
  background:
    radial-gradient(40% 50% at 82% 30%, rgb(115 70 240 / .16), transparent 70%),
    radial-gradient(38% 46% at 62% 70%, rgb(18 181 214 / .16), transparent 70%),
    radial-gradient(45% 50% at 10% 10%, rgb(36 86 232 / .12), transparent 70%);
}
.hero-bg::after {
  content: ""; position: absolute; inset: 0;
  background-image: linear-gradient(var(--line) 1px, transparent 1px), linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(60% 60% at 50% 30%, #000 10%, transparent 75%);
  -webkit-mask-image: radial-gradient(60% 60% at 50% 30%, #000 10%, transparent 75%);
  opacity: .55;
}
.hero-grid { display: grid; grid-template-columns: 1.08fr .92fr; gap: 56px; align-items: center; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 6px 14px 6px 10px; margin-bottom: 22px;
  border-radius: 999px; border: 1px solid var(--line); background: var(--card);
  color: var(--ink-2); font-size: .9rem; font-weight: 600; box-shadow: var(--shadow-sm);
}
.eyebrow .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--grad); box-shadow: 0 0 0 4px rgb(18 181 214 / .18); }
.hero h1 { margin-bottom: 22px; }
.lead { color: var(--ink-2); font-size: 1.12rem; line-height: 1.65; }
.lead strong { color: var(--ink); font-weight: 600; }
.hero-cta { display: flex; flex-wrap: wrap; gap: 12px; margin: 32px 0 26px; }
.hero-points { list-style: none; padding: 0; margin: 0; display: flex; flex-wrap: wrap; gap: 10px 22px; color: var(--ink-2); font-size: .95rem; font-weight: 500; }
.hero-points li { display: inline-flex; align-items: center; gap: 7px; }
.hero-points .ic { color: var(--ok); width: 1.1em; height: 1.1em; stroke-width: 2.6; }

.hero-visual { position: relative; display: flex; justify-content: center; }
.float-chip {
  position: absolute; z-index: 2;
  display: inline-flex; align-items: center; gap: 8px;
  padding: 10px 14px; border-radius: 14px;
  background: var(--card); color: var(--ink); border: 1px solid var(--line);
  font-size: .88rem; font-weight: 600; box-shadow: var(--shadow);
  animation: bob 6s ease-in-out infinite;
}
.float-chip .ic { color: var(--brand); }
.float-chip b { color: var(--brand); font-weight: 700; }
.chip-a { left: -8px; top: 22%; }
.chip-b { right: -14px; bottom: 5%; animation-delay: -3s; }
@keyframes bob { 50% { transform: translateY(-8px); } }

@media (max-width: 960px) {
  .hero { padding: 48px 0 64px; }
  .hero-grid { grid-template-columns: 1fr; gap: 48px; }
  .hero-copy { text-align: center; }
  .hero-cta, .hero-points { justify-content: center; }
  .chip-a { left: 0; top: -14px; }
  .chip-b { right: 0; bottom: -14px; }
}
@media (max-width: 480px) {
  .hero-cta .btn { width: 100%; }
  .float-chip { font-size: .8rem; padding: 8px 11px; }
  .chip-a { left: -4px; }
  .chip-b { right: -4px; }
}

/* ---------- điện thoại minh hoạ ---------- */
.phone {
  position: relative; width: 330px; max-width: 100%; aspect-ratio: 330 / 660;
  padding: 11px; border-radius: 50px;
  background: linear-gradient(145deg, #2a3350, #0b1022);
  box-shadow: var(--shadow-lg), inset 0 0 0 2px rgb(255 255 255 / .08);
}
.phone::before { /* tai thỏ */
  content: ""; position: absolute; top: 20px; left: 50%; translate: -50% 0; z-index: 3;
  width: 96px; height: 26px; border-radius: 20px; background: #05070f;
}
.phone-screen {
  position: relative; height: 100%; overflow: hidden; border-radius: 40px;
  display: flex; flex-direction: column; background: var(--tg-in);
  font-size: 14px; line-height: 1.42; color: var(--tg-text);
}
.chat-head {
  display: flex; align-items: center; gap: 10px;
  padding: 54px 16px 10px; background: var(--tg-head);
  border-bottom: 1px solid rgb(0 0 0 / .06); z-index: 2;
}
.chat-head img { border-radius: 50%; }
.chat-head b { display: block; font-size: 15px; font-weight: 600; }
.chat-head small { display: block; font-size: 12.5px; color: var(--tg-sub); }
.chat-head small.typing { color: var(--tg-accent); }

.tg-wall { position: relative; background: var(--tg-wall); }
.tg-wall::before {
  content: ""; position: absolute; inset: 0; pointer-events: none;
  background: var(--tg-pattern);
  mask: url(assets/tg-pattern.svg) 0 0 / 220px 220px repeat;
  -webkit-mask: url(assets/tg-pattern.svg) 0 0 / 220px 220px repeat;
}
.chat-body {
  flex: 1; display: flex; flex-direction: column; justify-content: flex-end; gap: 6px;
  padding: 12px 10px 10px; overflow: hidden;
}
.chat-body > * { position: relative; }
.day-chip {
  align-self: center; margin-bottom: 4px; padding: 2px 10px; border-radius: 12px;
  background: rgb(116 131 145 / .45); color: #fff; font-size: 12.5px; font-weight: 500;
}
.msg {
  max-width: 84%; padding: 6px 10px 6px; border-radius: 16px;
  box-shadow: 0 1px 1px rgb(0 0 0 / .12);
  animation: pop .35s cubic-bezier(.2, .9, .3, 1.2) both;
}
.msg p + p { margin-top: 6px; }
.msg.in { align-self: flex-start; background: var(--tg-in); border-bottom-left-radius: 5px; }
.msg.out { align-self: flex-end; background: var(--tg-out); border-bottom-right-radius: 5px; }
.msg .meta { float: right; margin: 6px 0 -4px 10px; font-size: 11.5px; color: var(--tg-time-in); }
.msg.out .meta { color: var(--tg-time-out); }
.msg .ticks { font-style: normal; color: var(--tg-tick); letter-spacing: -3px; margin-left: 2px; }
.msg .src { font-size: 12.5px; color: var(--tg-sub); }
.msg .media {
  display: grid; place-items: center; height: 120px; margin: 2px -6px 6px; border-radius: 12px;
  background: linear-gradient(135deg, #2456e8, #12b5d6); color: #fff; font-weight: 600; font-size: 13px;
  text-align: center; padding: 0 12px;
}
.msg .media small { display: block; font-weight: 400; opacity: .85; }
.msg .react {
  position: absolute; bottom: -10px; left: -6px;
  padding: 1px 5px; border-radius: 10px; font-size: 11px;
  background: var(--tg-in); box-shadow: 0 1px 2px rgb(0 0 0 / .2);
  animation: pop .3s cubic-bezier(.2, .9, .3, 1.4) both;
}
.msg.out:has(.react) { margin-bottom: 8px; }
.msg.typing { display: inline-flex; gap: 4px; padding: 12px 14px; }
.msg.typing i { width: 7px; height: 7px; border-radius: 50%; background: var(--tg-sub); animation: dot 1.2s infinite; }
.msg.typing i:nth-child(2) { animation-delay: .15s; }
.msg.typing i:nth-child(3) { animation-delay: .3s; }
@keyframes dot { 0%, 60%, 100% { opacity: .35; transform: none; } 30% { opacity: 1; transform: translateY(-3px); } }
@keyframes pop { from { opacity: 0; transform: translateY(8px) scale(.96); } }
.chat-input {
  display: flex; align-items: center; justify-content: space-between;
  margin: 0; padding: 10px 14px 26px; background: var(--tg-head);
  color: var(--tg-sub); font-size: 14px;
}
.chat-input span { flex: 1; padding: 7px 14px; margin-right: 10px; border-radius: 18px; background: var(--tg-in); border: 1px solid rgb(0 0 0 / .08); }
.chat-input .ic { color: var(--tg-sub); }

/* danh sách chat (mục App) */
.phone-sm { width: 320px; }
.list-screen { background: var(--tg-list); }
.list-head { display: flex; align-items: center; justify-content: center; position: relative; padding: 54px 16px 8px; font-size: 16px; }
.list-head .pen { position: absolute; right: 18px; bottom: 8px; font-size: 16px; }
.list-search {
  display: flex; align-items: center; justify-content: center; gap: 6px;
  margin: 4px 12px 8px; padding: 7px; border-radius: 10px;
  background: rgb(118 118 128 / .12); color: var(--tg-sub); font-size: 14px;
}
.list-search .ic { width: 15px; height: 15px; }
.chat-list { list-style: none; margin: 0; padding: 0; }
.chat-list li { display: flex; align-items: center; gap: 10px; padding: 8px 12px; }
.chat-list li + li .cl-main, .chat-list li + li .cl-side { border-top: 1px solid var(--tg-sep); }
.av {
  position: relative; flex: none; width: 50px; height: 50px; border-radius: 50%;
  display: grid; place-items: center; color: #fff; font-weight: 600; font-size: 16px;
}
.av-c1 { background: linear-gradient(#ffb36b, #f07a3a); }
.av-c2 { background: linear-gradient(#72d5fd, #2a9ef1); }
.av-c3 { background: linear-gradient(#e0a2f3, #d669ed); }
.av-c4 { background: linear-gradient(#a0de7e, #54cb68); }
.av .online { position: absolute; right: 1px; bottom: 1px; width: 13px; height: 13px; border-radius: 50%; background: #2fc65b; border: 2px solid var(--tg-list); }
.cl-main { flex: 1; min-width: 0; align-self: stretch; display: flex; flex-direction: column; justify-content: center; padding: 6px 0; }
.cl-main b { font-weight: 600; font-size: 15px; display: flex; align-items: center; gap: 4px; }
.cl-main b .mute { width: 13px; height: 13px; color: var(--tg-sub); }
.cl-main span { color: var(--tg-sub); font-size: 13.5px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.cl-main em { font-style: normal; color: var(--tg-text); }
.cl-side { align-self: stretch; display: flex; flex-direction: column; align-items: flex-end; justify-content: center; gap: 4px; padding: 6px 0; }
.cl-side time { font-size: 12.5px; color: var(--tg-sub); }
.cl-side .tick { font-size: 12px; color: var(--tg-tick); letter-spacing: -3px; }
.badge {
  display: inline-flex; align-items: center; gap: 3px; min-width: 21px; height: 21px; padding: 0 6px;
  border-radius: 11px; background: var(--tg-accent); color: #fff; font-size: 12px; font-weight: 600; justify-content: center;
}
.badge i { font-style: normal; }
.badge.muted { background: #a8a8ad; }

/* ---------- dải kênh ---------- */
.strip { border-block: 1px solid var(--line); background: var(--bg-soft); }
.strip-inner { display: flex; align-items: center; justify-content: space-between; gap: 18px 32px; flex-wrap: wrap; padding-block: 22px; }
.strip p { color: var(--ink-3); font-weight: 600; font-size: .92rem; text-transform: uppercase; letter-spacing: .06em; }
.channels { list-style: none; margin: 0; padding: 0; display: flex; flex-wrap: wrap; gap: 10px 28px; }
.channels li { display: inline-flex; align-items: center; gap: 9px; font-weight: 600; color: var(--ink); }
.channels img { border-radius: 6px; }
.channels small { color: var(--ink-3); font-weight: 500; }
.ch-dot { width: 22px; height: 22px; border-radius: 6px; display: grid; place-items: center; color: #fff; font-size: 12px; font-weight: 800; }
.ch-dot .ic { width: 13px; height: 13px; }
.ch-dot.zalo { background: #0068ff; }
.ch-dot.tele { background: #27a7e7; }
.ch-dot.web { background: var(--violet); }
@media (max-width: 760px) { .strip-inner { justify-content: center; text-align: center; } .channels { justify-content: center; } }

/* ---------- khung section ---------- */
.section { padding: 104px 0; }
.section.soft { background: var(--bg-soft); }
@media (max-width: 760px) { .section { padding: 72px 0; } }
.section-head { max-width: 760px; margin: 0 auto 56px; text-align: center; }
.section-head h2 + .lead { margin-top: 16px; }
.kicker {
  display: inline-block; margin-bottom: 14px;
  color: var(--brand); font-weight: 700; font-size: .85rem; letter-spacing: .1em; text-transform: uppercase;
}

.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 28px; box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease, border-color .2s ease;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.card h3 { margin: 18px 0 8px; }
.card p { color: var(--ink-2); font-size: .98rem; }
.ic-box {
  display: inline-grid; place-items: center; width: 46px; height: 46px; border-radius: 13px;
  color: var(--brand); background: color-mix(in srgb, var(--brand) 11%, transparent);
}
.ic-box .ic { width: 22px; height: 22px; }
.ic-box.warn { color: var(--warn); background: var(--warn-bg); }

/* vấn đề */
.pain-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
@media (max-width: 1040px) { .pain-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .pain-grid { grid-template-columns: 1fr; } }
.bridge {
  max-width: 820px; margin: 48px auto 0; padding: 22px 28px; border-radius: var(--radius);
  text-align: center; font-size: 1.12rem; color: var(--ink-2);
  background: linear-gradient(var(--card), var(--card)) padding-box, var(--grad) border-box;
  border: 1.5px solid transparent;
}
.bridge strong { color: var(--ink); }

/* các bước */
.steps { list-style: none; margin: 0; padding: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 22px; counter-reset: s; }
@media (max-width: 900px) { .steps { grid-template-columns: 1fr; max-width: 560px; margin: 0 auto; } }
.step { position: relative; background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 30px 28px; box-shadow: var(--shadow-sm); }
.step h3 { margin: 18px 0 8px; font-size: 1.2rem; }
.step p { color: var(--ink-2); font-size: .98rem; }
.step-no {
  position: absolute; top: 22px; right: 24px;
  font-size: 3.2rem; font-weight: 800; line-height: 1;
  background: var(--grad); -webkit-background-clip: text; background-clip: text; color: transparent; opacity: .28;
}
.tags { list-style: none; margin: 18px 0 0; padding: 0; display: flex; flex-wrap: wrap; gap: 6px; }
.tags li { padding: 3px 10px; border-radius: 8px; background: var(--bg-soft); border: 1px solid var(--line); font-size: .82rem; font-weight: 600; color: var(--ink-2); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
.code-demo { display: flex; gap: 6px; margin-top: 18px; }
.code-demo span {
  width: 38px; height: 46px; border-radius: 10px; display: grid; place-items: center;
  font-weight: 800; font-size: 1.15rem; color: var(--brand);
  background: var(--bg-soft); border: 1.5px solid var(--line);
}

/* tính năng */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feature-hero { grid-column: span 2; grid-row: span 2; display: flex; flex-direction: column; }
.feature-hero h3 { font-size: 1.45rem; }
.feature-hero > p { font-size: 1.04rem; max-width: 60ch; }
@media (max-width: 1040px) { .feature-grid { grid-template-columns: repeat(2, 1fr); } .feature-hero { grid-row: auto; } }
@media (max-width: 640px) { .feature-grid { grid-template-columns: 1fr; } .feature-hero { grid-column: auto; } }
.cite-demo {
  margin-top: auto; padding-top: 24px;
  display: flex; flex-direction: column; gap: 10px; font-size: .94rem;
}
.cite-q, .cite-a { max-width: 88%; padding: 10px 14px; border-radius: 16px; }
.cite-q { align-self: flex-end; background: var(--grad); color: #fff; border-bottom-right-radius: 5px; font-weight: 500; }
.cite-a { align-self: flex-start; background: var(--bg-soft); border: 1px solid var(--line); border-bottom-left-radius: 5px; color: var(--ink); }
.cite-a.muted-a { color: var(--ink-2); }
.cite-src {
  display: inline-block; margin-top: 8px; padding: 3px 10px; border-radius: 8px;
  font-size: .82rem; font-weight: 600; color: var(--ok); background: var(--ok-bg);
}

/* tab phòng ban */
.tabs { max-width: 1040px; margin: 0 auto; }
.tab-list {
  display: flex; gap: 6px; padding: 6px; margin: 0 auto 28px; width: fit-content; max-width: 100%;
  border-radius: 999px; background: var(--card); border: 1px solid var(--line); box-shadow: var(--shadow-sm);
  overflow-x: auto; scrollbar-width: none;
}
.tab-list::-webkit-scrollbar { display: none; }
.tab-list button {
  flex: none; padding: 10px 18px; border: 0; border-radius: 999px; cursor: pointer;
  background: transparent; color: var(--ink-2); font-family: inherit; font-size: .95rem; font-weight: 600; line-height: 1;
  transition: background-color .2s ease, color .2s ease;
}
.tab-list button:hover { color: var(--ink); }
.tab-list button[aria-selected="true"] { background: var(--grad); color: #fff; }
.tab-panel {
  display: grid; grid-template-columns: 1.1fr .9fr; gap: 40px; align-items: center;
  padding: 40px; border-radius: 24px; background: var(--card); border: 1px solid var(--line); box-shadow: var(--shadow);
  animation: fade .35s ease both;
}
.tab-panel[hidden] { display: none; }
.tab-panel h3 { font-size: 1.5rem; margin-bottom: 12px; }
.tab-panel p { color: var(--ink-2); }
@keyframes fade { from { opacity: 0; transform: translateY(6px); } }
@media (max-width: 820px) { .tab-panel { grid-template-columns: 1fr; padding: 28px 22px; gap: 26px; } }
.checks { list-style: none; margin: 20px 0 0; padding: 0; display: grid; gap: 10px; }
.checks li { display: flex; align-items: flex-start; gap: 10px; font-weight: 500; }
.checks .ic { color: var(--ok); margin-top: .2em; stroke-width: 2.6; width: 1.1em; height: 1.1em; }
.checks.big { gap: 14px; margin-top: 28px; }
.checks.big li { font-weight: 400; color: var(--ink-2); }
.checks.big b { color: var(--ink); font-weight: 600; }
.q-list { list-style: none; margin: 0; padding: 22px; display: flex; flex-direction: column; gap: 10px; border-radius: 20px; background: var(--tg-wall); position: relative; overflow: hidden; }
.q-list li {
  position: relative; align-self: flex-end; max-width: 92%;
  padding: 9px 14px; border-radius: 16px; border-bottom-right-radius: 5px;
  background: var(--tg-out); color: var(--tg-text); font-size: .95rem; box-shadow: 0 1px 1px rgb(0 0 0 / .12);
}
.q-list li:nth-child(even) { align-self: flex-start; border-radius: 16px; border-bottom-left-radius: 5px; background: var(--tg-in); }

/* app */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.split h2 { margin-bottom: 16px; }
.split-visual { display: flex; justify-content: center; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; gap: 48px; } }

/* máy tính */
.calc { display: grid; grid-template-columns: 1.15fr .85fr; gap: 24px; max-width: 1040px; margin: 0 auto; }
@media (max-width: 860px) { .calc { grid-template-columns: 1fr; } }
.calc-inputs { display: grid; gap: 26px; padding: 34px; border-radius: 24px; background: var(--card); border: 1px solid var(--line); box-shadow: var(--shadow-sm); }
.range { display: grid; gap: 10px; }
.range-top { display: flex; justify-content: space-between; align-items: baseline; gap: 16px; font-weight: 600; }
.range-top small { display: block; font-weight: 400; color: var(--ink-3); font-size: .84rem; }
.range output { flex: none; color: var(--brand); font-weight: 700; font-variant-numeric: tabular-nums; }
input[type="range"] {
  --p: 50%;
  -webkit-appearance: none; appearance: none; width: 100%; height: 8px; border-radius: 8px; margin: 6px 0;
  background: linear-gradient(90deg, var(--brand) 0 var(--p), var(--line) var(--p) 100%); cursor: pointer;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; width: 24px; height: 24px; border-radius: 50%;
  background: #fff; border: 3px solid var(--brand); box-shadow: 0 2px 8px rgb(36 86 232 / .35);
}
input[type="range"]::-moz-range-thumb {
  width: 18px; height: 18px; border-radius: 50%;
  background: #fff; border: 3px solid var(--brand); box-shadow: 0 2px 8px rgb(36 86 232 / .35);
}
.calc-result {
  display: flex; flex-direction: column; gap: 18px; padding: 34px; border-radius: 24px; color: #fff;
  background: radial-gradient(120% 80% at 100% 0%, rgb(115 70 240 / .55), transparent 60%), linear-gradient(160deg, #1b3fc0, #0e1a4a);
  box-shadow: var(--shadow-lg);
}
.res-row { display: flex; flex-direction: column; gap: 2px; padding-bottom: 16px; border-bottom: 1px solid rgb(255 255 255 / .14); }
.res-row span, .res-main span { color: rgb(255 255 255 / .72); font-size: .93rem; }
.res-row b { font-size: 1.35rem; font-weight: 700; font-variant-numeric: tabular-nums; }
.res-main { display: flex; flex-direction: column; gap: 2px; padding-bottom: 16px; border-bottom: 1px solid rgb(255 255 255 / .14); }
.res-main b { font-size: clamp(2rem, 4vw, 2.6rem); font-weight: 800; line-height: 1.15; letter-spacing: -.02em; font-variant-numeric: tabular-nums; }
.res-main em { font-style: normal; font-size: 1.15rem; font-weight: 600; color: #7ee8ff; }
.calc-result .fine { font-size: .82rem; color: rgb(255 255 255 / .6); }
.calc-result .btn { margin-top: auto; background: #fff; color: #1b3fc0; box-shadow: none; }
.calc-result .btn:hover { color: #1b3fc0; }

/* bảo mật */
.section.dark {
  color: #e9edf8;
  background:
    radial-gradient(50% 60% at 90% 0%, rgb(115 70 240 / .25), transparent 70%),
    radial-gradient(50% 60% at 0% 100%, rgb(18 181 214 / .18), transparent 70%),
    #08102a;
}
.section.dark .kicker { color: #7ee8ff; }
.section.dark .lead { color: #a9b2c9; }
.sec-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
@media (max-width: 1040px) { .sec-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .sec-grid { grid-template-columns: 1fr; } }
.sec { padding: 26px; border-radius: var(--radius); background: rgb(255 255 255 / .04); border: 1px solid rgb(255 255 255 / .09); }
.sec .ic { width: 28px; height: 28px; color: #7ee8ff; }
.sec h3 { margin: 16px 0 8px; font-size: 1.06rem; }
.sec p { color: #a9b2c9; font-size: .95rem; }

/* so sánh */
.table-wrap { overflow-x: auto; border-radius: 22px; border: 1px solid var(--line); background: var(--card); box-shadow: var(--shadow-sm); }
.compare { width: 100%; min-width: 760px; border-collapse: collapse; font-size: .95rem; }
.compare th, .compare td { padding: 16px 18px; text-align: center; border-bottom: 1px solid var(--line); }
.compare tbody tr:last-child > * { border-bottom: 0; }
.compare thead th { font-size: .9rem; font-weight: 600; color: var(--ink-2); vertical-align: bottom; line-height: 1.35; }
.compare thead th.us { color: var(--ink); font-size: 1.05rem; font-weight: 800; }
.compare thead th.us img { display: block; margin: 0 auto 6px; border-radius: 6px; }
.compare tbody th { text-align: left; font-weight: 600; width: 30%; }
.compare .us { background: color-mix(in srgb, var(--brand) 7%, transparent); }
.compare td span { display: inline-flex; align-items: center; gap: 6px; font-size: .85rem; font-weight: 600; white-space: nowrap; }
.compare td .ic { width: 26px; height: 26px; padding: 5px; border-radius: 50%; stroke-width: 3; }
.compare .y { color: var(--ok); } .compare .y .ic { background: var(--ok-bg); }
.compare .n { color: var(--no); } .compare .n .ic { background: var(--no-bg); }
.compare .p { color: var(--warn); } .compare .p .ic { background: var(--warn-bg); }
@media (max-width: 760px) {
  /* bảng cuộn ngang trên điện thoại: giữ cột tiêu chí đứng yên */
  .compare { min-width: 680px; }
  .compare th, .compare td { padding: 14px 12px; }
  .compare tbody th, .compare thead th:first-child { position: sticky; left: 0; z-index: 1; min-width: 156px; background: var(--card); box-shadow: 1px 0 0 var(--line); }
}

/* hỏi đáp */
.faq { display: grid; gap: 12px; }
.faq details { background: var(--card); border: 1px solid var(--line); border-radius: 16px; transition: border-color .2s ease, box-shadow .2s ease; }
.faq details[open] { border-color: color-mix(in srgb, var(--brand) 45%, var(--line)); box-shadow: var(--shadow-sm); }
.faq summary {
  display: flex; justify-content: space-between; align-items: center; gap: 16px;
  padding: 20px 24px; cursor: pointer; list-style: none; font-weight: 600; font-size: 1.04rem;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; flex: none; width: 12px; height: 12px; margin-right: 4px;
  border-right: 2.5px solid var(--ink-3); border-bottom: 2.5px solid var(--ink-3);
  transform: rotate(45deg) translateY(-3px); transition: transform .2s ease;
}
.faq details[open] summary::after { transform: rotate(225deg) translateY(-3px); }
.faq details p { padding: 0 24px 22px; color: var(--ink-2); }

/* liên hệ */
.section.cta {
  background:
    radial-gradient(60% 80% at 100% 0%, rgb(115 70 240 / .14), transparent 70%),
    radial-gradient(60% 80% at 0% 100%, rgb(18 181 214 / .14), transparent 70%),
    var(--bg);
}
.cta-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
@media (max-width: 900px) { .cta-grid { grid-template-columns: 1fr; gap: 36px; } }
.cta-copy h2 { font-size: clamp(2rem, 4vw, 3rem); margin-bottom: 18px; }
.contact { list-style: none; margin: 30px 0 0; padding: 0; display: grid; gap: 12px; }
.contact li { display: flex; align-items: center; gap: 12px; font-weight: 600; font-size: 1.05rem; }
.contact .ic { color: var(--brand); }
.contact a { color: var(--ink); }
.lead-form {
  display: grid; gap: 16px; padding: 34px; border-radius: 24px;
  background: var(--card); border: 1px solid var(--line); box-shadow: var(--shadow);
}
.lead-form h3 { font-size: 1.35rem; margin-bottom: 4px; }
.lead-form label { display: grid; gap: 6px; font-size: .92rem; font-weight: 600; color: var(--ink-2); }
.lead-form label em { color: var(--no); font-style: normal; }
.lead-form input, .lead-form select, .lead-form textarea {
  width: 100%; padding: 12px 14px; border-radius: 12px; border: 1.5px solid var(--line);
  background: var(--bg); color: var(--ink); font-family: inherit; font-size: 1rem; line-height: 1.4;
  transition: border-color .2s ease, box-shadow .2s ease;
}
.lead-form textarea { resize: vertical; }
.lead-form input:focus, .lead-form select:focus, .lead-form textarea:focus {
  outline: none; border-color: var(--brand); box-shadow: 0 0 0 4px color-mix(in srgb, var(--brand) 18%, transparent);
}
.lead-form .invalid { border-color: var(--no); }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
@media (max-width: 480px) { .form-row { grid-template-columns: 1fr; } .lead-form { padding: 24px 18px; } }
.lead-form .btn { margin-top: 4px; }
.form-msg { font-size: .92rem; color: var(--ink-2); min-height: 1.4em; }
.form-msg.ok { color: var(--ok); }
.form-msg.err { color: var(--no); }

/* chân trang */
.site-footer { border-top: 1px solid var(--line); padding: 36px 0; background: var(--bg-soft); }
.foot { display: flex; align-items: center; flex-wrap: wrap; gap: 14px 28px; }
.foot p { color: var(--ink-3); font-size: .93rem; }
.foot nav { display: flex; gap: 20px; margin-left: auto; }
.foot nav a { color: var(--ink-2); font-size: .93rem; }
.foot small { color: var(--ink-3); width: 100%; }
@media (max-width: 700px) { .foot { flex-direction: column; text-align: center; } .foot nav { margin: 0; flex-wrap: wrap; justify-content: center; } }

/* hiện dần khi cuộn (chỉ khi có JS) */
.js .reveal { opacity: 0; transform: translateY(18px); transition: opacity .6s ease, transform .6s ease; }
.js .reveal.in { opacity: 1; transform: none; }
@media (prefers-reduced-motion: reduce) {
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .float-chip, .msg, .msg .react, .tab-panel { animation: none; }
}