:root {
  --bg: #f6f5ff;
  --ink: #1c1b29;
  --mute: #6b6880;
  --line: #e6e3f5;
  --card: #ffffff;
  --accent: #6d5efc;      /* friendly indigo/violet */
  --accent-2: #ff7a9a;    /* warm coral */
  --mint: #37d0a8;
  --radius: 18px;
  --shadow: 0 12px 40px rgba(85, 70, 200, 0.10);
  font-family: "Inter", system-ui, -apple-system, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.55;
  overflow-x: hidden;
}

/* language show/hide */
.i18n > .en { display: none; }
html.en .i18n > .vi { display: none; }
html.en .i18n > .en { display: inline; }

h1, h2, h3, .brand, .step-n, kbd, .btn { font-family: "Space Grotesk", system-ui, sans-serif; }

/* soft background blobs */
.blob { position: fixed; border-radius: 50%; filter: blur(70px); opacity: 0.55; z-index: -1; }
.blob-a { width: 460px; height: 460px; background: radial-gradient(circle, #b7aaff, transparent 70%); top: -140px; right: -80px; }
.blob-b { width: 420px; height: 420px; background: radial-gradient(circle, #ffc2d1, transparent 70%); bottom: -160px; left: -120px; }

.nav {
  max-width: 1040px; margin: 0 auto; padding: 22px 24px;
  display: flex; align-items: center; justify-content: space-between;
}
.brand { font-weight: 700; font-size: 1.25rem; color: var(--ink); text-decoration: none; display: flex; align-items: center; gap: 9px; }
.brand-dot { width: 12px; height: 12px; border-radius: 50%; background: linear-gradient(135deg, var(--accent), var(--accent-2)); box-shadow: 0 0 0 4px rgba(109,94,252,0.15); }
.nav-links { display: flex; align-items: center; gap: 22px; }
.nav-links a { color: var(--mute); text-decoration: none; font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--ink); }
.lang-toggle {
  border: 1px solid var(--line); background: var(--card); color: var(--ink);
  border-radius: 999px; padding: 6px 14px; font-weight: 600; cursor: pointer; font-size: 0.85rem;
}
.lang-toggle:hover { border-color: var(--accent); color: var(--accent); }

main { max-width: 1040px; margin: 0 auto; padding: 0 24px; }

.hero { text-align: center; padding: 48px 0 26px; }
.eyebrow { text-transform: uppercase; letter-spacing: 0.14em; font-size: 0.75rem; font-weight: 600; color: var(--accent); margin: 0 0 14px; }
.hero h1 { font-size: clamp(2.3rem, 6vw, 4rem); line-height: 1.05; margin: 0 0 18px; letter-spacing: -0.02em; }
.grad { background: linear-gradient(120deg, var(--accent), var(--accent-2) 60%, var(--mint)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lede { max-width: 640px; margin: 0 auto 26px; color: #413e56; font-size: 1.12rem; }
.lede b { color: var(--ink); }

.cta-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; flex-direction: column; align-items: center;
  text-decoration: none; border-radius: 14px; padding: 13px 26px; font-weight: 600; font-size: 1.02rem;
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.btn small { font-weight: 500; font-size: 0.72rem; opacity: 0.8; margin-top: 2px; }
.btn.primary { background: linear-gradient(135deg, var(--accent), #8a6bff); color: #fff; box-shadow: var(--shadow); }
.btn.primary:hover { transform: translateY(-2px); box-shadow: 0 16px 46px rgba(109,94,252,0.32); }
.btn.ghost { justify-content: center; background: var(--card); color: var(--ink); border: 1px solid var(--line); }
.btn.ghost:hover { border-color: var(--accent); color: var(--accent); }
.fine { color: var(--mute); font-size: 0.85rem; margin-top: 14px; }

.keys { display: flex; gap: 12px; justify-content: center; margin: 40px 0 8px; flex-wrap: wrap; }
.key {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 14px 22px; display: flex; flex-direction: column; align-items: center; gap: 8px;
  min-width: 96px; box-shadow: 0 6px 18px rgba(85,70,200,0.06);
}
kbd {
  background: #f0edff; border: 1px solid #ddd6ff; border-bottom-width: 3px;
  border-radius: 9px; padding: 6px 12px; font-size: 1.05rem; color: var(--accent); font-weight: 600;
}
.key span { color: var(--mute); font-size: 0.9rem; font-weight: 500; }

section.steps { padding: 46px 0 20px; text-align: center; }
section.steps h2, section.two h2 { font-size: clamp(1.5rem, 3vw, 2rem); margin: 0 0 26px; letter-spacing: -0.01em; }
.step-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.step {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 26px 22px; text-align: left; box-shadow: 0 6px 18px rgba(85,70,200,0.05);
}
.step-n {
  display: inline-flex; align-items: center; justify-content: center; width: 34px; height: 34px;
  border-radius: 10px; background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-weight: 700; margin-bottom: 12px;
}
.step h3 { margin: 0 0 6px; font-size: 1.12rem; }
.step p { margin: 0; color: var(--mute); font-size: 0.96rem; }
.step b { color: var(--ink); }

section.two { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; padding: 30px 0 60px; }
.card { border-radius: var(--radius); padding: 28px; }
.card.soft { background: var(--card); border: 1px solid var(--line); box-shadow: 0 6px 18px rgba(85,70,200,0.05); }
.card.accent { background: linear-gradient(150deg, #efeaff, #fdeef3); border: 1px solid #e7ddff; }
.card h2 { text-align: left; margin: 0 0 14px; }
.bullets { margin: 0; padding: 0; list-style: none; display: grid; gap: 10px; }
.bullets li { position: relative; padding-left: 26px; color: #413e56; }
.bullets li::before { content: "✓"; position: absolute; left: 0; color: var(--mint); font-weight: 700; }
.card-kicker { font-weight: 700; color: var(--accent); margin: 0 0 8px; }
.card.accent p { color: #413e56; }
.mute { color: var(--mute); font-size: 0.9rem; }

.foot {
  max-width: 1040px; margin: 0 auto; padding: 26px 24px 40px;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  border-top: 1px solid var(--line); color: var(--mute); font-size: 0.9rem;
}
.foot a { color: var(--accent); text-decoration: none; }
.foot a:hover { text-decoration: underline; }

@media (max-width: 760px) {
  .step-grid { grid-template-columns: 1fr; }
  section.two { grid-template-columns: 1fr; }
  .nav-links { gap: 14px; }
  .nav-links a[href="#how"], .nav-links a[href="#privacy"] { display: none; }
}