:root {
  --bg: #ffffff;
  --surface: #f6f7f9;
  --border: #e4e6ea;
  --text: #17181c;
  --muted: #5c6270;
  --accent: #2b6cf6;
  --accent-soft: #eef4ff;
  --radius: 14px;
  --max: 1040px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font: 16px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

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

.container { max-width: var(--max); margin: 0 auto; padding: 0 24px; }

/* ---- nav ---- */
nav {
  position: sticky;
  top: 0;
  background: rgba(255, 255, 255, .86);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
  z-index: 10;
}
nav .container { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { font-weight: 700; letter-spacing: -.01em; }
nav .links { display: flex; gap: 22px; font-size: 14px; }
nav .links a { color: var(--muted); }

/* ---- hero ---- */
header { padding: 72px 0 56px; }
.hero { display: grid; grid-template-columns: 1.1fr .9fr; gap: 48px; align-items: center; }
@media (max-width: 860px) { .hero { grid-template-columns: 1fr; } }

h1 { font-size: 40px; line-height: 1.15; letter-spacing: -.02em; margin: 0 0 16px; }
.lead { font-size: 18px; color: var(--muted); margin: 0 0 28px; }
.cta-row { display: flex; gap: 12px; flex-wrap: wrap; }

.btn {
  display: inline-block;
  padding: 12px 20px;
  border-radius: 10px;
  font-weight: 600;
  font-size: 15px;
  border: 1px solid var(--border);
  background: #fff;
  color: var(--text);
}
.btn.primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn:hover { text-decoration: none; transform: translateY(-1px); }

.note { font-size: 13px; color: var(--muted); margin-top: 14px; }

/* ---- before/after mock ---- */
.ba {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 10px;
  padding: 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
}
.ba .panel { border-radius: 10px; overflow: hidden; aspect-ratio: 4/3; position: relative; }
.ba .before { background: linear-gradient(140deg, #dfe6f2, #b9c6de 45%, #8fa3c4); }
.ba .before::after {
  content: "subject";
  position: absolute; inset: auto auto 36% 40%;
  width: 40%; height: 52%;
  background: radial-gradient(circle at 50% 30%, #6d7686 0 18%, transparent 19%),
              linear-gradient(#5f6875, #4b5361);
  border-radius: 48% 48% 30% 30%;
  filter: blur(.5px);
  color: transparent;
}
.ba .after {
  background-color: #fff;
  background-image:
    linear-gradient(45deg, #e8eaee 25%, transparent 25%),
    linear-gradient(-45deg, #e8eaee 25%, transparent 25%),
    linear-gradient(45deg, transparent 75%, #e8eaee 75%),
    linear-gradient(-45deg, transparent 75%, #e8eaee 75%);
  background-size: 18px 18px;
  background-position: 0 0, 0 9px, 9px -9px, -9px 0;
}
.ba .after::after {
  content: "";
  position: absolute; inset: auto auto 36% 40%;
  width: 40%; height: 52%;
  background: radial-gradient(circle at 50% 30%, #6d7686 0 18%, transparent 19%),
              linear-gradient(#5f6875, #4b5361);
  border-radius: 48% 48% 30% 30%;
}
.ba .arrow { color: var(--muted); font-size: 20px; }
.ba figcaption { grid-column: 1 / -1; text-align: center; font-size: 13px; color: var(--muted); }

/* ---- sections ---- */
section { padding: 56px 0; border-top: 1px solid var(--border); }
h2 { font-size: 26px; letter-spacing: -.01em; margin: 0 0 8px; }
.sub { color: var(--muted); margin: 0 0 32px; }

.grid3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
@media (max-width: 860px) { .grid3 { grid-template-columns: 1fr; } }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 20px; }
.card h3 { margin: 0 0 6px; font-size: 16px; }
.card p { margin: 0; color: var(--muted); font-size: 14px; }

/* ---- comparison table ---- */
table { width: 100%; border-collapse: collapse; font-size: 15px; }
th, td { text-align: left; padding: 12px 14px; border-bottom: 1px solid var(--border); vertical-align: top; }
th { font-size: 13px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
td:first-child { color: var(--muted); width: 34%; }
.pro-col { background: var(--accent-soft); }

/* ---- pricing ---- */
.price-card {
  max-width: 420px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  background: #fff;
  box-shadow: 0 18px 40px -30px rgba(23, 24, 28, .35);
}
.price { font-size: 38px; font-weight: 700; letter-spacing: -.02em; }
.price small { font-size: 15px; font-weight: 500; color: var(--muted); }
.price-card ul { padding-left: 18px; color: var(--muted); font-size: 14px; margin: 14px 0 20px; }
.price-card li { margin: 6px 0; }

/* ---- faq ---- */
details { border-bottom: 1px solid var(--border); padding: 14px 0; }
summary { cursor: pointer; font-weight: 600; }
details p { color: var(--muted); margin: 10px 0 0; }

/* ---- footer ---- */
footer { padding: 40px 0 56px; border-top: 1px solid var(--border); color: var(--muted); font-size: 14px; }
footer .container { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; }

/* ---- policy pages ---- */
.policy { max-width: 760px; padding: 48px 0 64px; }
.policy h2 { margin-top: 36px; }
.policy li { margin: 6px 0; }
.policy .todo { background: #fff6e5; border: 1px dashed #e6b95c; border-radius: 6px; padding: 0 6px; }