/* tap-to-view.click
 *
 * Font self-host, không gọi Google Fonts: một trang bán sản phẩm privacy mà
 * nhúng request bên thứ ba thì tự mâu thuẫn. Cả trang không có một request
 * ra ngoài domain nào.
 */

@font-face {
  font-family: "Instrument Serif";
  src: url(fonts/instrument-serif-400.woff2) format("woff2");
  font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url(fonts/plex-mono-400.woff2) format("woff2");
  font-weight: 400; font-style: normal; font-display: swap;
}
@font-face {
  font-family: "IBM Plex Mono";
  src: url(fonts/plex-mono-500.woff2) format("woff2");
  font-weight: 500; font-style: normal; font-display: swap;
}

:root {
  --ink: #0b0f14;
  --ink-2: #10161e;
  --panel: #131a23;
  --line: #1e2731;
  --line-soft: #171e27;
  --text: #e8eef5;
  --muted: #7b8797;
  --dim: #56616f;
  --accent: #4c8dff;

  --display: "Instrument Serif", Georgia, "Times New Roman", serif;
  --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, Menlo, monospace;

  --gutter: clamp(20px, 5vw, 64px);
  --measure: 1120px;
}

*, *::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(--ink);
  color: var(--text);
  font: 400 15px/1.7 var(--mono);
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Hạt nhiễu rất nhẹ để nền tối không bị phẳng và không bị banding gradient. */
body::before {
  content: "";
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  opacity: 0.032;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='140' height='140' filter='url(%23n)'/%3E%3C/svg%3E");
}

.wrap { width: 100%; max-width: var(--measure); margin: 0 auto; padding: 0 var(--gutter); position: relative; z-index: 1; }

a { color: inherit; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

/* ---------- nhãn micro ---------- */

.label {
  font: 500 11px/1 var(--mono);
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--dim);
}

/* ---------- logo ---------- */

.mark { position: relative; width: var(--m, 20px); height: var(--m, 20px); flex: none; display: block; }
.mark::before, .mark::after {
  content: ""; position: absolute; top: calc(var(--m, 20px) * 0.167);
  width: calc(var(--m, 20px) * 0.667); height: calc(var(--m, 20px) * 0.667);
  border-radius: 50%; background: var(--accent);
}
.mark::before { left: 0; filter: blur(calc(var(--m, 20px) * 0.167)); opacity: 0.75; }
.mark::after { left: calc(var(--m, 20px) * 0.333); }

/* ---------- header ---------- */

.site-head {
  position: relative; z-index: 3;
  border-bottom: 1px solid var(--line-soft);
}
.site-head .wrap { display: flex; align-items: center; gap: 18px; height: 68px; }
.brand { display: flex; align-items: center; gap: 10px; text-decoration: none; margin-right: auto; }
.brand .word { font: 500 15px/1 var(--mono); letter-spacing: -0.01em; }
.site-head nav { display: flex; align-items: center; gap: 26px; }
.site-head nav a { font-size: 13px; color: var(--muted); text-decoration: none; transition: color 160ms ease; }
.site-head nav a:hover { color: var(--text); }
@media (max-width: 640px) { .site-head nav a.hide-sm { display: none; } }

/* ---------- hero ---------- */

.hero { padding: clamp(56px, 10vw, 116px) 0 clamp(48px, 8vw, 96px); }
.hero .wrap { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 0.78fr); gap: clamp(32px, 6vw, 76px); align-items: center; }
@media (max-width: 900px) { .hero .wrap { grid-template-columns: 1fr; } }

.hero h1 {
  font: 400 clamp(46px, 7.4vw, 88px)/0.96 var(--display);
  letter-spacing: -0.02em;
  margin: 18px 0 0;
  text-wrap: balance;
}
.hero h1 em { font-style: italic; color: var(--accent); }

.lead { margin: 22px 0 0; max-width: 42ch; color: var(--muted); font-size: 15px; }

.cta { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.btn {
  display: inline-flex; align-items: center; gap: 9px;
  height: 44px; padding: 0 20px; border-radius: 8px;
  font: 500 13px/1 var(--mono); text-decoration: none;
  border: 1px solid transparent; transition: transform 140ms ease, background 160ms ease, border-color 160ms ease;
}
.btn-primary { background: var(--accent); color: #06101f; }
.btn-primary:hover { background: #6ba4ff; transform: translateY(-1px); }
.btn-ghost { border-color: var(--line); color: var(--text); }
.btn-ghost:hover { border-color: #33405020; background: var(--ink-2); border-color: #2b3644; }
.btn[aria-disabled="true"] { opacity: 0.45; pointer-events: none; }

.cta-note { margin: 14px 0 0; font-size: 12px; color: var(--dim); }

/* ---------- ống kính trang trí ---------- */

.lens {
  position: relative; aspect-ratio: 4 / 4.4; border-radius: 16px; overflow: hidden;
  border: 1px solid var(--line); background: var(--ink-2);
  cursor: crosshair;
}
@media (max-width: 900px) { .lens { aspect-ratio: 16 / 10; } }

.lens-field {
  position: absolute; inset: 0;
  background:
    radial-gradient(60% 45% at 22% 18%, #2f6feb 0%, transparent 60%),
    radial-gradient(55% 40% at 78% 30%, #db6d28 0%, transparent 62%),
    radial-gradient(70% 50% at 60% 82%, #238636 0%, transparent 64%),
    radial-gradient(50% 40% at 12% 78%, #8957e5 0%, transparent 60%),
    #0d131b;
}

/* Lưới chấm mảnh. Không có chi tiết tần số cao thì blur một gradient mềm
   trông y hệt bản gốc — ống kính sẽ vô hình. Chấm nhỏ bị blur thành vệt,
   nên ranh giới nét/mờ đọc được ngay. */
.lens-field::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    radial-gradient(circle at 1px 1px, rgba(255, 255, 255, 0.5) 1px, transparent 1.6px),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, 0.07) 0 1px, transparent 1px 52px);
  background-size: 13px 13px, auto;
}

/* Lớp mờ nằm trên, bị khoét một lỗ tròn ở vị trí con trỏ — nên phần "nét"
   thực chất là lớp dưới lộ ra. Không phải ảnh chụp, không phải UI của
   extension: đây là hình trang trí, cố ý không giả làm giao diện sản phẩm. */
.lens-blur {
  position: absolute; inset: -2px;
  backdrop-filter: blur(26px) saturate(1.15);
  -webkit-backdrop-filter: blur(26px) saturate(1.15);
  -webkit-mask-image: radial-gradient(circle var(--r, 104px) at var(--x, 50%) var(--y, 42%), transparent 0%, transparent 62%, #000 100%);
  mask-image: radial-gradient(circle var(--r, 104px) at var(--x, 50%) var(--y, 42%), transparent 0%, transparent 62%, #000 100%);
  transition: -webkit-mask-image 90ms linear, mask-image 90ms linear;
}
.lens-ring {
  position: absolute; width: calc(var(--r, 104px) * 1.24); aspect-ratio: 1;
  left: var(--x, 50%); top: var(--y, 42%); translate: -50% -50%;
  border: 1px solid rgba(255, 255, 255, 0.28); border-radius: 50%;
  pointer-events: none; transition: left 90ms linear, top 90ms linear;
}
.lens-cap {
  position: absolute; left: 14px; right: 14px; bottom: 12px;
  font: 400 11px/1.5 var(--mono); color: rgba(255, 255, 255, 0.55);
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.7);
}

@media (prefers-reduced-motion: reduce) {
  .lens-blur, .lens-ring { transition: none; }
}

/* ---------- khối section ---------- */

.section { padding: clamp(56px, 8vw, 104px) 0; border-top: 1px solid var(--line-soft); }
.section-head { display: grid; grid-template-columns: 120px minmax(0, 1fr); gap: 24px; align-items: baseline; }
@media (max-width: 720px) { .section-head { grid-template-columns: 1fr; gap: 10px; } }
.section h2 {
  font: 400 clamp(30px, 4.2vw, 46px)/1.06 var(--display);
  letter-spacing: -0.015em; margin: 0; text-wrap: balance;
}
.section p.intro { margin: 16px 0 0; color: var(--muted); max-width: 56ch; }

/* ---------- demo thật ---------- */

.demo { margin-top: 40px; }
.frame {
  border: 1px solid var(--line); border-radius: 14px; overflow: hidden;
  background: #11161d; box-shadow: 0 40px 90px rgba(0, 0, 0, 0.5);
}
.frame-bar {
  display: flex; align-items: center; gap: 9px; height: 40px; padding: 0 14px;
  background: #161b22; border-bottom: 1px solid var(--line);
}
.frame-bar i { width: 9px; height: 9px; border-radius: 50%; background: #2b333f; }
.frame-bar .u {
  flex: 1; margin-left: 6px; height: 22px; border-radius: 6px; background: #0d1117;
  display: flex; align-items: center; padding: 0 10px;
  font-size: 11px; color: var(--dim);
}
.frame-body { padding: 18px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
@media (max-width: 700px) { .frame-body { grid-template-columns: repeat(2, 1fr); } }

.shot { border: 0; padding: 0; background: none; display: block; cursor: pointer; border-radius: 9px; }
.shot img {
  display: block; width: 100%; height: 128px; object-fit: cover; border-radius: 9px;
  /* Giống hệt extension/src/blur.css của bản phát hành. */
  filter: blur(14px); clip-path: inset(0);
  transition: filter 160ms ease;
}
.shot[data-shown] img { filter: none; }
@media (prefers-reduced-motion: reduce) { .shot img { transition: none; } }

.demo-bar {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  margin-top: 16px; font-size: 12px; color: var(--dim); flex-wrap: wrap;
}
.demo-bar b { color: var(--text); font-weight: 500; }
.linkish {
  background: none; border: 0; padding: 0; color: var(--accent);
  font: inherit; cursor: pointer; text-decoration: underline; text-underline-offset: 3px;
}

/* ---------- danh sách đánh số ---------- */

.steps { margin: 44px 0 0; padding: 0; list-style: none; }
.steps li {
  display: grid; grid-template-columns: 120px minmax(0, 1fr); gap: 24px;
  padding: 26px 0; border-top: 1px solid var(--line-soft);
}
@media (max-width: 720px) { .steps li { grid-template-columns: 1fr; gap: 8px; } }
.steps h3 { margin: 0 0 8px; font: 400 22px/1.25 var(--display); letter-spacing: -0.01em; }
.steps p { margin: 0; color: var(--muted); max-width: 60ch; font-size: 14px; }

/* ---------- bảng privacy ---------- */

.claim {
  margin-top: 40px; padding: clamp(28px, 5vw, 52px);
  border: 1px solid var(--line); border-radius: 16px;
  background: linear-gradient(160deg, var(--panel), var(--ink-2) 70%);
}
.claim h2 { font-size: clamp(28px, 4vw, 42px); margin: 0 0 26px; }
.facts { margin: 0; padding: 0; list-style: none; display: grid; gap: 1px; background: var(--line-soft); border-radius: 10px; overflow: hidden; }
.facts li { background: var(--ink-2); padding: 15px 18px; display: flex; gap: 16px; align-items: baseline; font-size: 13px; }
.facts .k { color: var(--dim); min-width: 118px; flex: none; }
.facts .v { color: var(--text); }
.facts .v.no { color: var(--muted); }

/* ---------- footer ---------- */

.site-foot { border-top: 1px solid var(--line-soft); padding: 44px 0 60px; }
.site-foot .wrap { display: flex; flex-wrap: wrap; gap: 20px 34px; align-items: center; }
.site-foot a { color: var(--muted); text-decoration: none; font-size: 13px; }
.site-foot a:hover { color: var(--text); }
.site-foot .spacer { margin-left: auto; }
.site-foot small { color: var(--dim); font-size: 12px; }

/* ---------- trang tài liệu (/privacy) ---------- */

.doc { padding: clamp(48px, 7vw, 88px) 0 clamp(60px, 8vw, 110px); }
.doc-head { border-bottom: 1px solid var(--line-soft); padding-bottom: 30px; margin-bottom: 42px; }
.doc h1 { font: 400 clamp(38px, 6vw, 62px)/1 var(--display); letter-spacing: -0.02em; margin: 14px 0 0; }
.doc-meta { display: flex; flex-wrap: wrap; gap: 8px 28px; margin-top: 18px; font-size: 12px; color: var(--dim); }

.doc-body { max-width: 68ch; }
.doc-body h2 {
  font: 500 12px/1 var(--mono); letter-spacing: 0.16em; text-transform: uppercase;
  color: var(--accent); margin: 52px 0 16px;
}
.doc-body h2:first-child { margin-top: 0; }
.doc-body p { margin: 0 0 18px; color: #c4ced9; font-size: 14px; line-height: 1.85; }
.doc-body strong { color: var(--text); font-weight: 500; }
.doc-body ul { margin: 0 0 18px; padding-left: 20px; color: #c4ced9; font-size: 14px; line-height: 1.85; }
.doc-body li { margin-bottom: 10px; }
.doc-body li::marker { color: var(--dim); }
.doc-body a { color: var(--accent); text-underline-offset: 3px; }

.doc-body .callout {
  border-left: 2px solid var(--accent); background: var(--ink-2);
  padding: 18px 22px; margin: 0 0 30px; border-radius: 0 8px 8px 0;
}
.doc-body .callout p { margin: 0; color: var(--text); }

.perm { width: 100%; border-collapse: collapse; margin: 0 0 22px; font-size: 13px; }
.perm th, .perm td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--line-soft); vertical-align: top; }
.perm th { color: var(--dim); font-weight: 500; font-size: 11px; letter-spacing: 0.12em; text-transform: uppercase; }
.perm td:first-child { color: var(--accent); white-space: nowrap; }
.perm td { color: #c4ced9; }

/* ---------- xuất hiện khi tải trang ---------- */

@media (prefers-reduced-motion: no-preference) {
  .rise { animation: rise 700ms cubic-bezier(0.22, 0.7, 0.3, 1) both; }
  .rise:nth-of-type(2) { animation-delay: 70ms; }
  @keyframes rise {
    from { opacity: 0; transform: translateY(14px); }
    to { opacity: 1; transform: none; }
  }
}