/* Puracam — stylesheet dùng chung cho cả 4 trang.
   Không phụ thuộc mạng ngoài: font hệ thống, không CDN, không webfont. */

:root {
  --bg: #ffffff;
  --bg-soft: #f5f7f8;
  --text: #14201f;
  --text-dim: #5b6b6a;
  --line: #dfe6e5;
  --accent: #0f8b80;
  --accent-soft: #e6f4f2;
  --radius: 14px;
  --measure: 42rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d1413;
    --bg-soft: #141d1c;
    --text: #e8efee;
    --text-dim: #93a5a3;
    --line: #223231;
    --accent: #3ecfc0;
    --accent-soft: #14302d;
  }
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
        "Helvetica Neue", Arial, sans-serif;
  text-rendering: optimizeLegibility;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { max-width: var(--measure); margin: 0 auto; padding: 0 20px; }
.wrap-wide { max-width: 60rem; margin: 0 auto; padding: 0 20px; }

/* ---------- header / footer dùng chung ---------- */

header.site {
  border-bottom: 1px solid var(--line);
  padding: 18px 0;
}
header.site .row {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.brand {
  font-weight: 700; font-size: 19px; letter-spacing: -0.01em;
  color: var(--text); display: inline-flex; align-items: center; gap: 9px;
}
.brand:hover { text-decoration: none; }
/* Dấu hiệu = app icon thật (icon.svg), bo góc kiểu iOS. Nền icon là #101113 nên nó là
   một ô tối trên cả 2 theme — chủ đích, giống cách icon xuất hiện trên home screen. */
.brand .mark {
  width: 28px; height: 28px; border-radius: 7px; display: block;
}
nav.site a { color: var(--text-dim); font-size: 15px; margin-left: 18px; }
nav.site a:hover { color: var(--accent); }

footer.site {
  border-top: 1px solid var(--line);
  margin-top: 72px; padding: 28px 0 44px;
  color: var(--text-dim); font-size: 14px;
}
footer.site .row {
  display: flex; flex-wrap: wrap; gap: 8px 18px;
  align-items: center; justify-content: space-between;
}
footer.site nav a { margin-right: 16px; }

/* ---------- landing ---------- */

.hero { padding: 76px 0 8px; text-align: center; }
.hero h1 {
  font-size: clamp(2.4rem, 7vw, 3.6rem); line-height: 1.05;
  letter-spacing: -0.03em; margin: 0 0 14px;
}
.hero .tagline {
  font-size: clamp(1.05rem, 3vw, 1.3rem); color: var(--text-dim);
  margin: 0 auto 10px; max-width: 34rem;
}
.hero .sub { color: var(--text-dim); max-width: 34rem; margin: 0 auto 30px; }

.badge {
  display: inline-block; padding: 11px 22px; border-radius: 999px;
  background: var(--accent); color: #fff; font-weight: 600; font-size: 16px;
}
.badge:hover { text-decoration: none; opacity: 0.9; }
.badge.soon {
  background: var(--accent-soft); color: var(--accent);
  border: 1px solid var(--accent);
}

.features {
  display: grid; gap: 18px; margin: 64px 0 0;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.card {
  background: var(--bg-soft); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 22px;
}
.card h3 { margin: 0 0 7px; font-size: 17px; letter-spacing: -0.01em; }
.card p { margin: 0; color: var(--text-dim); font-size: 15px; }

.specs {
  margin: 56px 0 0; padding: 22px; border-radius: var(--radius);
  border: 1px solid var(--line); background: var(--bg-soft);
  font-size: 15px; color: var(--text-dim);
}
.specs dl { display: grid; grid-template-columns: max-content 1fr; gap: 8px 20px; margin: 0; }
.specs dt { color: var(--text); font-weight: 600; }
.specs dd { margin: 0; }

/* ---------- trang văn bản (privacy / terms / support) ---------- */

article { padding: 44px 0 0; }
article h1 {
  font-size: clamp(1.9rem, 5vw, 2.4rem); letter-spacing: -0.025em;
  margin: 0 0 6px; line-height: 1.15;
}
article .updated { color: var(--text-dim); font-size: 15px; margin: 0 0 34px; }
article h2 {
  font-size: 1.22rem; letter-spacing: -0.015em; margin: 40px 0 10px;
  padding-top: 20px; border-top: 1px solid var(--line);
}
article h3 { font-size: 1.02rem; margin: 24px 0 6px; }
article p, article li { color: var(--text); }
article ul, article ol { padding-left: 22px; }
article li { margin: 6px 0; }
article .lead { font-size: 1.06rem; color: var(--text-dim); }

.callout {
  border-left: 3px solid var(--accent); background: var(--accent-soft);
  padding: 14px 18px; border-radius: 0 var(--radius) var(--radius) 0;
  margin: 22px 0;
}
.callout p { margin: 0; }
.callout strong { color: var(--text); }

table.data {
  width: 100%; border-collapse: collapse; margin: 18px 0; font-size: 15px;
  display: block; overflow-x: auto;
}
table.data th, table.data td {
  text-align: left; padding: 9px 12px; border-bottom: 1px solid var(--line);
  vertical-align: top;
}
table.data th { color: var(--text); font-weight: 600; white-space: nowrap; }
table.data td { color: var(--text-dim); }

code {
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.9em; background: var(--bg-soft); padding: 1px 5px;
  border-radius: 5px; border: 1px solid var(--line);
}