/* Phông tự host: Bricolage Grotesque, IBM Plex Sans, IBM Plex Mono (SIL Open Font License 1.1, xem fonts/OFL-*.txt).
   Bộ latin, latin-ext, vietnamese; trình duyệt chỉ tải bộ ký tự trang cần. */
@font-face{font-family:"Bricolage Grotesque";font-style:normal;font-weight:500 700;font-display:swap;src:url(/fonts/bricolage-grotesque-var-vietnamese.woff2) format("woff2");unicode-range:U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB}
@font-face{font-family:"Bricolage Grotesque";font-style:normal;font-weight:500 700;font-display:swap;src:url(/fonts/bricolage-grotesque-var-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF}
@font-face{font-family:"Bricolage Grotesque";font-style:normal;font-weight:500 700;font-display:swap;src:url(/fonts/bricolage-grotesque-var-latin.woff2) format("woff2");unicode-range:U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:400;font-display:swap;src:url(/fonts/ibm-plex-mono-400-vietnamese.woff2) format("woff2");unicode-range:U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:400;font-display:swap;src:url(/fonts/ibm-plex-mono-400-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:400;font-display:swap;src:url(/fonts/ibm-plex-mono-400-latin.woff2) format("woff2");unicode-range:U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:500;font-display:swap;src:url(/fonts/ibm-plex-mono-500-vietnamese.woff2) format("woff2");unicode-range:U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:500;font-display:swap;src:url(/fonts/ibm-plex-mono-500-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF}
@font-face{font-family:"IBM Plex Mono";font-style:normal;font-weight:500;font-display:swap;src:url(/fonts/ibm-plex-mono-500-latin.woff2) format("woff2");unicode-range:U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD}
@font-face{font-family:"IBM Plex Sans";font-style:normal;font-weight:400 600;font-display:swap;src:url(/fonts/ibm-plex-sans-var-vietnamese.woff2) format("woff2");unicode-range:U+0102-0103, U+0110-0111, U+0128-0129, U+0168-0169, U+01A0-01A1, U+01AF-01B0, U+0300-0301, U+0303-0304, U+0308-0309, U+0323, U+0329, U+1EA0-1EF9, U+20AB}
@font-face{font-family:"IBM Plex Sans";font-style:normal;font-weight:400 600;font-display:swap;src:url(/fonts/ibm-plex-sans-var-latin-ext.woff2) format("woff2");unicode-range:U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+0304, U+0308, U+0329, U+1D00-1DBF, U+1E00-1E9F, U+1EF2-1EFF, U+2020, U+20A0-20AB, U+20AD-20C4, U+2113, U+2C60-2C7F, U+A720-A7FF}
@font-face{font-family:"IBM Plex Sans";font-style:normal;font-weight:400 600;font-display:swap;src:url(/fonts/ibm-plex-sans-var-latin.woff2) format("woff2");unicode-range:U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+0304, U+0308, U+0329, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD}

/* Postbackly. Bảng màu: chàm (màu nhấn chính, biến lịch sử tên --teal) + cam (click, conversion, cảnh báo nhẹ).
   Hình ảnh chủ đạo là "luồng": click → 302 → landing → postback → conversion, vẽ bằng chính URL thật của dịch vụ.
   Tiêu đề dùng IBM Plex Sans đậm; Bricolage Grotesque chỉ cho logo, giá và con số lớn (--f-brand).
   Tên biến giữ nguyên vì site/src/app.css (bảng điều khiển) dùng chung; chỉ đổi giá trị. */
:root {
  --paper: #f7f6fb;
  --surface: #ffffff;
  --ink: #17142b;
  --ink-2: #4a4662;
  --ink-3: #625d7a;
  --line: #e2dfee;
  --teal: #4b36c9;
  --teal-soft: #ebe8fc;
  --amber: #a8410a;
  --amber-soft: #fdebdc;
  --code-bg: #f1eff9;
  --hero-bg: #1b1442;
  --hero-ink: #f1effc;
  --hero-muted: #b3acd9;
  --hero-line: #3a3172;
  /* biểu đồ: 2 chuỗi (hợp lệ / bot hoặc bị đánh dấu); tương phản ≥ 3:1 với --surface ở cả hai chế độ */
  --viz-clean: #5a46de;
  --viz-flag: #d4600a;
  --danger: #b42318;
  --danger-soft: #fdecea;
  /* màu riêng của trang giới thiệu */
  --accent-2: #ff8f45;
  --hero-accent: #ffb37a;
  --hero-key: #c9bfff;

  --f-display: "IBM Plex Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
  --f-brand: "Bricolage Grotesque", "Avenir Next", "Segoe UI", system-ui, sans-serif;
  --f-body: "IBM Plex Sans", "Segoe UI", system-ui, -apple-system, sans-serif;
  --f-mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;

  --s-1: 0.25rem; --s-2: 0.5rem; --s-3: 0.75rem; --s-4: 1rem; --s-5: 1.5rem; --s-6: 2rem; --s-7: 3rem; --s-8: 4.5rem; --s-9: 6rem;
  --t-xs: 0.8125rem; --t-sm: 0.9375rem; --t-md: 1.0625rem; --t-lg: 1.3125rem; --t-xl: 1.875rem; --t-2xl: clamp(2.1rem, 1.35rem + 3vw, 3.4rem);
  --radius: 14px;
  --max: 74rem;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #110f1d; --surface: #1a1729; --ink: #ecebf5; --ink-2: #bdb8d6; --ink-3: #8f89ad; --line: #2e2a45;
    --teal: #ab9fff; --teal-soft: #2a2352; --amber: #ffa25a; --amber-soft: #3d2614; --code-bg: #1f1b33;
    --hero-bg: #0e0b22; --hero-ink: #f1effc; --hero-muted: #aaa3d2; --hero-line: #2f2862;
    --viz-clean: #8a7bff; --viz-flag: #e8822f; --danger: #f97066; --danger-soft: #3a1714;
    color-scheme: dark;
  }
}
:root[data-theme="dark"] {
  --paper: #110f1d; --surface: #1a1729; --ink: #ecebf5; --ink-2: #bdb8d6; --ink-3: #8f89ad; --line: #2e2a45;
  --teal: #ab9fff; --teal-soft: #2a2352; --amber: #ffa25a; --amber-soft: #3d2614; --code-bg: #1f1b33;
  --hero-bg: #0e0b22; --hero-ink: #f1effc; --hero-muted: #aaa3d2; --hero-line: #2f2862;
  --viz-clean: #8a7bff; --viz-flag: #e8822f; --danger: #f97066; --danger-soft: #3a1714;
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body { margin: 0; background: var(--paper); color: var(--ink); font: 400 var(--t-md)/1.65 var(--f-body); }
img, svg { max-width: 100%; }
a { color: var(--teal); text-underline-offset: 3px; }
a:hover { text-decoration-thickness: 2px; }
:focus-visible { outline: 2px solid var(--teal); outline-offset: 3px; border-radius: 4px; }
h1, h2, h3 { font-family: var(--f-display); font-weight: 600; line-height: 1.15; letter-spacing: -0.02em; text-wrap: balance; margin: 0; }
h2 { font-size: var(--t-xl); }
h3 { font-size: var(--t-lg); letter-spacing: -0.01em; }
p { margin: 0; }
code, .mono { font-family: var(--f-mono); font-size: 0.88em; }
:not(pre) > code { background: var(--code-bg); padding: 0.1em 0.35em; border-radius: 5px; overflow-wrap: anywhere; }
pre { margin: 0; font: 400 var(--t-xs)/1.7 var(--f-mono); background: var(--code-bg); border: 1px solid var(--line); border-left: 3px solid var(--teal);
  border-radius: 8px; padding: var(--s-4) var(--s-5); overflow-x: auto; }
/* ví dụ trong tài liệu: xuống dòng thay vì cuộn ngang, để phần url=... luôn thấy được ở màn hẹp */
.prose pre { white-space: pre-wrap; overflow-wrap: anywhere; }
.prose td code, .nowrap { white-space: nowrap; }
.prose td code.wrap-any { white-space: normal; }
.sr-skip { position: absolute; left: -9999px; top: 8px; z-index: 100; background: var(--surface); color: var(--teal); padding: 8px 12px;
  border-radius: 8px; border: 1px solid var(--line); }
.sr-skip:focus { left: 16px; }

.wrap { max-width: var(--max); margin: 0 auto; padding-left: max(16px, env(safe-area-inset-left, 0px)); padding-right: max(16px, env(safe-area-inset-right, 0px)); }
.eyebrow { font: 600 var(--t-xs)/1.4 var(--f-body); letter-spacing: 0.08em; text-transform: uppercase; color: var(--teal); }
.lede { font-size: var(--t-lg); line-height: 1.5; color: var(--ink-2); max-width: 40rem; }
.muted { color: var(--ink-3); }

/* thanh trên cùng */
.top { position: sticky; top: env(safe-area-inset-top, 0px); z-index: 20; background: color-mix(in srgb, var(--surface) 92%, transparent);
  backdrop-filter: blur(10px); border-bottom: 1px solid var(--line); }
body::before { content: ""; position: fixed; inset: 0 0 auto; height: env(safe-area-inset-top, 0px); z-index: 30; background: var(--surface); }
.top .wrap { display: flex; align-items: center; gap: var(--s-5); min-height: 64px; flex-wrap: wrap; padding-block: var(--s-2); }
.logo { display: inline-flex; align-items: center; gap: 0.55rem; font: 700 1.22rem/1 var(--f-brand); color: var(--ink); text-decoration: none; letter-spacing: -0.025em; }
.logo svg { width: 28px; height: 28px; flex: none; }
.nav { display: flex; gap: var(--s-5); flex-wrap: wrap; margin-left: auto; align-items: center; font-size: var(--t-sm); }
.nav a { color: var(--ink-2); text-decoration: none; }
.nav a:hover, .nav a[aria-current="page"] { color: var(--teal); }
.nav a[aria-current="page"] { font-weight: 600; }
.nav .lang { font-size: var(--t-xs); border: 1px solid var(--line); padding: 3px 10px; border-radius: 999px; }
.btn { display: inline-flex; align-items: center; justify-content: center; gap: var(--s-2); font: 600 var(--t-sm)/1 var(--f-body);
  padding: 0.8rem 1.25rem; border-radius: 999px; border: 1px solid transparent; text-decoration: none; cursor: pointer; }
.btn-primary { background: var(--teal); color: var(--surface); }
.btn-primary:hover { filter: brightness(1.1); }
.btn-ghost { border-color: var(--line); color: var(--ink); background: transparent; }
.btn-ghost:hover { border-color: var(--ink-3); }
.nav .btn { padding: 0.6rem 1rem; color: var(--surface); }
.nav .btn-ghost { color: var(--ink); }
.nav-form { display: contents; }

/* hero: luồng click → postback */
.hero { position: relative; background: var(--hero-bg); color: var(--hero-ink); padding-block: var(--s-8) var(--s-7); overflow: hidden;
  background-image: radial-gradient(circle at 1px 1px, rgba(201, 191, 255, 0.13) 1px, transparent 0); background-size: 22px 22px; }
.hero::after { content: ""; position: absolute; inset: auto -10% -60% 40%; height: 120%; background: radial-gradient(closest-side, rgba(255, 143, 69, 0.16), transparent); pointer-events: none; }
.hero .wrap { position: relative; z-index: 1; }
.hero-text { max-width: 46rem; }
.hero h1 { font-size: var(--t-2xl); letter-spacing: -0.03em; }
.hero h1 em { font-style: normal; color: var(--hero-accent); }
.hero .eyebrow { color: var(--hero-accent); }
.hero .lede { color: var(--hero-muted); margin-top: var(--s-5); }
.hero .actions { display: flex; gap: var(--s-3); flex-wrap: wrap; margin-top: var(--s-6); }
.hero .btn-ghost { color: var(--hero-ink); border-color: var(--hero-line); }
.hero .btn-ghost:hover { border-color: var(--hero-muted); }
.hero .btn-primary { background: var(--accent-2); color: #1c0f02; }
.hero :not(pre) > code { background: rgba(255, 255, 255, 0.1); color: var(--hero-ink); }
.hero-note { margin-top: var(--s-4); font-size: var(--t-xs); color: var(--hero-muted); }

.flow { list-style: none; margin: var(--s-7) 0 0; padding: 0; display: grid; grid-template-columns: repeat(5, minmax(0, 1fr)); gap: var(--s-4); }
.flow-step { position: relative; display: grid; gap: var(--s-2); align-content: start; min-width: 0; padding: var(--s-4);
  background: rgba(255, 255, 255, 0.04); border: 1px solid var(--hero-line); border-radius: var(--radius); }
.flow-step:not(:last-child)::after { content: ""; position: absolute; top: 1.55rem; right: calc(-1 * var(--s-4) - 1px); width: var(--s-4); height: 2px;
  background: var(--accent-2); }
.flow-k { display: flex; align-items: center; gap: var(--s-2); font: 600 0.72rem/1 var(--f-mono); letter-spacing: 0.06em; text-transform: uppercase; color: var(--hero-accent); }
.flow-k b { display: inline-grid; place-items: center; width: 1.45rem; height: 1.45rem; border-radius: 50%; background: rgba(255, 143, 69, 0.16); color: var(--hero-accent); font-weight: 600; }
.flow-step h3 { font: 600 var(--t-sm)/1.35 var(--f-body); letter-spacing: 0; color: var(--hero-ink); }
.flow-step code { display: block; font: 400 0.75rem/1.55 var(--f-mono); color: var(--hero-muted); background: rgba(0, 0, 0, 0.22); border-radius: 8px;
  padding: var(--s-2) var(--s-3); overflow-wrap: anywhere; }
.flow-step p { font-size: var(--t-xs); color: var(--hero-muted); line-height: 1.5; }
.flow .k { color: var(--hero-key); } .flow .v { color: #ffd9bd; }
.flow .hl { color: #ffffff; background: rgba(255, 143, 69, 0.28); border-radius: 3px; padding: 0 3px; }
.flow .ok { color: #9ff0c4; }
.flow-step.is-conv { border-color: rgba(255, 143, 69, 0.55); background: rgba(255, 143, 69, 0.08); }
@media (prefers-reduced-motion: no-preference) {
  .flow-step { animation: rise 0.5s ease-out both; }
  .flow-step:nth-child(2) { animation-delay: 0.12s; } .flow-step:nth-child(3) { animation-delay: 0.24s; }
  .flow-step:nth-child(4) { animation-delay: 0.36s; } .flow-step:nth-child(5) { animation-delay: 0.48s; }
  @keyframes rise { from { transform: translateY(8px); opacity: 0.3; } to { transform: none; opacity: 1; } }
}

/* các section */
.section { padding-block: var(--s-8); }
.section + .section { border-top: 1px solid var(--line); }
.section.alt { background: var(--surface); }
.section-head { display: grid; gap: var(--s-3); max-width: 46rem; margin-bottom: var(--s-6); }
.split { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr); gap: var(--s-7); align-items: start; }
.steps { display: grid; gap: 0; counter-reset: step; }
.step { display: grid; grid-template-columns: 2.5rem minmax(0, 1fr); gap: var(--s-4); padding-block: var(--s-5); border-top: 1px solid var(--line); }
.step:first-child { border-top: 0; padding-top: 0; }
.step::before { counter-increment: step; content: counter(step); font: 600 var(--t-sm)/2.2rem var(--f-mono); width: 2.2rem; height: 2.2rem;
  text-align: center; border-radius: 10px; background: var(--teal-soft); color: var(--teal); }
.step h3 { font-size: var(--t-md); font-family: var(--f-body); font-weight: 600; letter-spacing: 0; margin-bottom: var(--s-1); }
.step p { color: var(--ink-2); font-size: var(--t-sm); }

/* ba nhóm người dùng */
.who-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--s-4); }
.who { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: var(--s-5) var(--s-5) var(--s-6); display: grid; gap: var(--s-3); align-content: start;
  border-top: 4px solid var(--teal); }
.who:nth-child(2) { border-top-color: var(--accent-2); }
.who:nth-child(3) { border-top-color: var(--ink-3); }
.who h3 { font-size: 1.15rem; }
.who p { color: var(--ink-2); font-size: var(--t-sm); }
.who ul { margin: 0; padding-left: 1.1rem; display: grid; gap: var(--s-1); font-size: var(--t-sm); color: var(--ink-2); }

.features { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--s-4); }
.feature { display: grid; gap: var(--s-2); align-content: start; padding: var(--s-5); border-radius: var(--radius); background: var(--paper); border: 1px solid var(--line); }
.feature .tag { justify-self: start; font: 500 0.72rem/1 var(--f-mono); color: var(--teal); background: var(--teal-soft); padding: 4px 8px; border-radius: 999px; }
.feature h3 { font-size: 1.1rem; }
.feature p { color: var(--ink-2); font-size: var(--t-sm); }

/* bảng báo cáo minh hoạ */
.sample-report { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.sample-report header { display: flex; flex-wrap: wrap; gap: var(--s-2) var(--s-4); align-items: baseline; justify-content: space-between; padding: var(--s-4) var(--s-5); border-bottom: 1px solid var(--line); }
.sample-report header b { font-weight: 600; }
.sample-report table { border-collapse: collapse; width: 100%; font-size: var(--t-sm); font-variant-numeric: tabular-nums; }
.sample-report th, .sample-report td { padding: var(--s-3) var(--s-5); text-align: right; border-bottom: 1px solid var(--line); white-space: nowrap; }
.sample-report th:first-child, .sample-report td:first-child { text-align: left; }
.sample-report th { font: 600 var(--t-xs)/1.3 var(--f-body); color: var(--ink-3); text-transform: uppercase; letter-spacing: 0.05em; }
.sample-report tbody tr:last-child td { border-bottom: 0; }
.sample-report td code { font-size: 0.85em; }
.chip { display: inline-block; font: 500 0.72rem/1.5 var(--f-mono); padding: 1px 8px; border-radius: 999px; background: var(--amber-soft); color: var(--amber); }

/* vòng đời conversion: pending → approved / rejected */
.lifecycle { display: flex; flex-wrap: wrap; align-items: center; gap: var(--s-2); margin-top: var(--s-2); font: 500 var(--t-xs)/1 var(--f-mono); }
.lifecycle span { padding: 6px 10px; border-radius: 999px; border: 1px solid var(--line); background: var(--surface); }
.lifecycle .st-pending { background: var(--amber-soft); color: var(--amber); border-color: transparent; }
.lifecycle .st-approved { background: var(--teal-soft); color: var(--teal); border-color: transparent; }
.lifecycle .st-rejected { background: var(--danger-soft); color: var(--danger); border-color: transparent; }
.lifecycle i { font-style: normal; color: var(--ink-3); }

.rule-box { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: var(--s-6); display: grid; gap: var(--s-4); }
.checks { list-style: none; padding: 0; margin: 0; display: grid; gap: var(--s-3); }
.checks li { display: grid; grid-template-columns: 1.4rem minmax(0, 1fr); gap: var(--s-2); font-size: var(--t-sm); color: var(--ink-2); }
.checks li::before { content: "✓"; color: var(--teal); font-weight: 700; }
.flag { display: inline-block; font: 500 0.72rem/1.5 var(--f-mono); padding: 0 6px; border-radius: 4px; }
.flag-ok { background: var(--teal-soft); color: var(--teal); }
.flag-warn { background: var(--amber-soft); color: var(--amber); }
.callout { border: 1px solid var(--line); border-left: 4px solid var(--accent-2); background: var(--surface); border-radius: 8px; padding: var(--s-4) var(--s-5); font-size: var(--t-sm); color: var(--ink-2); display: grid; gap: var(--s-2); }
.callout strong { color: var(--ink); }

/* dải kêu gọi cuối trang */
.band { background: var(--teal); color: var(--surface); border-radius: calc(var(--radius) + 4px); padding: var(--s-7) var(--s-6); display: flex; flex-wrap: wrap; gap: var(--s-5);
  align-items: center; justify-content: space-between; }
.band h2 { font-size: var(--t-xl); max-width: 34rem; }
.band p { opacity: 0.9; margin-top: var(--s-2); max-width: 36rem; }
.band .btn { background: var(--surface); color: var(--teal); }

/* bảng giá */
.plans { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: var(--s-4); }
.plan { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: var(--s-6); display: grid; gap: var(--s-4); align-content: start; position: relative; }
.plan.featured { border-color: var(--teal); box-shadow: 0 0 0 1px var(--teal), 0 18px 40px -24px color-mix(in srgb, var(--teal) 60%, transparent); }
.plan .badge { position: absolute; top: -0.75rem; left: var(--s-6); font: 600 0.72rem/1 var(--f-body); letter-spacing: 0.04em; text-transform: uppercase;
  background: var(--accent-2); color: #1c0f02; padding: 6px 10px; border-radius: 999px; }
.plan .price { font: 700 2.4rem/1 var(--f-brand); letter-spacing: -0.03em; }
.plan .price small { font: 400 var(--t-sm)/1 var(--f-body); color: var(--ink-3); letter-spacing: 0; }
.plan .alt-price { font-size: var(--t-xs); color: var(--ink-3); margin-top: calc(-1 * var(--s-3)); }
.plan .limits { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--s-2); margin: 0; }
.plan .limits div { background: var(--paper); border-radius: 10px; padding: var(--s-3); }
.plan .limits dt { font-size: var(--t-xs); color: var(--ink-3); }
.plan .limits dd { margin: 0; font: 700 1.15rem/1.2 var(--f-brand); letter-spacing: -0.01em; }
.plan ul { margin: 0; padding-left: 1.1rem; display: grid; gap: var(--s-2); font-size: var(--t-sm); color: var(--ink-2); }
.faq { display: grid; gap: var(--s-3); max-width: 50rem; }
.faq details { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; padding: var(--s-4) var(--s-5); }
.faq summary { cursor: pointer; font-weight: 600; }
.faq details p { margin-top: var(--s-3); color: var(--ink-2); font-size: var(--t-sm); }

/* trang nội dung: tài liệu, pháp lý */
.doc { display: grid; grid-template-columns: 14rem minmax(0, 1fr); gap: var(--s-7); padding-block: var(--s-7) var(--s-8); }
.doc nav { position: sticky; top: calc(env(safe-area-inset-top, 0px) + 84px); align-self: start; display: grid; gap: 2px; font-size: var(--t-sm);
  border-left: 2px solid var(--line); }
.doc nav a { color: var(--ink-2); text-decoration: none; padding: 3px 0 3px var(--s-3); margin-left: -2px; border-left: 2px solid transparent; }
.doc nav a:hover { color: var(--teal); border-left-color: var(--teal); }
.prose { max-width: 48rem; display: grid; gap: var(--s-4); min-width: 0; }
.prose h1 { font-size: var(--t-xl); }
.prose h2 { font-size: var(--t-lg); margin-top: var(--s-5); scroll-margin-top: 96px; padding-top: var(--s-4); border-top: 1px solid var(--line); }
.prose h3 { font-size: var(--t-md); font-family: var(--f-body); font-weight: 600; letter-spacing: 0; margin-top: var(--s-2); scroll-margin-top: 96px; }
.prose ul, .prose ol { margin: 0; padding-left: 1.25rem; display: grid; gap: var(--s-2); }
.prose table { border-collapse: collapse; width: 100%; font-size: var(--t-sm); }
.prose th, .prose td { text-align: left; vertical-align: top; padding: var(--s-2) var(--s-3); border-bottom: 1px solid var(--line); }
.prose th { font-weight: 600; background: var(--code-bg); }
.prose .label { font: 600 var(--t-xs)/1.4 var(--f-mono); color: var(--ink-3); text-transform: uppercase; letter-spacing: 0.05em; margin-bottom: calc(-1 * var(--s-2)); }
.code-ok { color: var(--teal); font-weight: 600; }
.code-err { color: var(--amber); font-weight: 600; }
.table-scroll { overflow-x: auto; }
.page-head { padding-block: var(--s-8) var(--s-6); display: grid; gap: var(--s-4); }
.page-head h1 { font-size: var(--t-2xl); max-width: 52rem; letter-spacing: -0.03em; }

/* form */
.form { display: grid; gap: var(--s-4); background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: var(--s-6); }
.form label { display: grid; gap: var(--s-1); font-size: var(--t-sm); font-weight: 500; }
.form input, .form select, .form textarea { font: inherit; font-weight: 400; color: var(--ink); background: var(--paper); border: 1px solid var(--line);
  border-radius: 10px; padding: 0.65rem 0.8rem; width: 100%; }
.form textarea { min-height: 7rem; resize: vertical; }
.form .row { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--s-4); }
.form .hp { position: absolute; left: -9999px; }
.notice { padding: var(--s-3) var(--s-4); border-radius: 10px; background: var(--amber-soft); color: var(--amber); font-size: var(--t-sm); }
.facts { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: var(--s-2) var(--s-5); margin: 0; font-size: var(--t-sm); }
.facts dt { color: var(--ink-3); }
.facts dd { margin: 0; overflow-wrap: anywhere; }

/* dùng chung với phần ứng dụng (site/src/app.css): form, thông báo, nút nhỏ */
.form .hint { font-weight: 400; font-size: var(--t-xs); color: var(--ink-3); }
.form label.check { display: grid; grid-template-columns: 1.25rem minmax(0, 1fr); gap: var(--s-2); align-items: start; font-weight: 400; color: var(--ink-2); }
.form label.check input { width: 1.05rem; height: 1.05rem; margin: 0.2rem 0 0; padding: 0; accent-color: var(--teal); }
.form [aria-invalid="true"] { border-color: var(--amber); }
.notice-ok { background: var(--teal-soft); color: var(--teal); }
.small { font-size: var(--t-xs); }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; border: 0; }
.btn-sm { padding: 0.5rem 0.85rem; font-size: var(--t-xs); }
.btn-danger { background: var(--danger); color: var(--surface); }
.btn-danger:disabled, .btn:disabled { opacity: 0.45; cursor: not-allowed; }

/* chân trang */
.foot { border-top: 1px solid var(--line); background: var(--surface); padding-block: var(--s-7); font-size: var(--t-sm); color: var(--ink-2); }
.foot .wrap { display: grid; grid-template-columns: minmax(0, 1.5fr) repeat(3, minmax(0, 1fr)); gap: var(--s-6); }
.foot h4 { font: 600 var(--t-xs)/1.4 var(--f-body); text-transform: uppercase; letter-spacing: 0.08em; color: var(--ink-3); margin: 0 0 var(--s-3); }
.foot ul { list-style: none; padding: 0; margin: 0; display: grid; gap: var(--s-2); }
.foot a { color: var(--ink-2); text-decoration: none; }
.foot a:hover { color: var(--teal); }
.foot .legal { display: grid; gap: var(--s-1); }
.foot .foot-tag { color: var(--ink); margin: var(--s-2) 0 var(--s-2); max-width: 22rem; }

@media (max-width: 900px) {
  .split, .doc { grid-template-columns: minmax(0, 1fr); }
  .features, .plans, .who-grid { grid-template-columns: minmax(0, 1fr); }
  .flow { grid-template-columns: minmax(0, 1fr); gap: var(--s-4); }
  .flow-step:not(:last-child)::after { top: auto; right: auto; left: 1.6rem; bottom: calc(-1 * var(--s-4) - 1px); width: 2px; height: var(--s-4); }
  .doc nav { position: static; border-left: 0; }
  .doc nav a { padding-left: 0; border-left: 0; }
  .foot .wrap { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .plans { gap: var(--s-6); }
}
@media (max-width: 560px) {
  .nav { gap: var(--s-4); margin-left: 0; width: 100%; }
  .form .row { grid-template-columns: minmax(0, 1fr); }
  .foot .wrap { grid-template-columns: minmax(0, 1fr); }
  .section { padding-block: var(--s-7); }
  .band { padding: var(--s-6) var(--s-5); }
  .sample-report th, .sample-report td { padding-inline: var(--s-3); }
}