:root {
  --bg: #f7f7f5;
  --surface: #ffffff;
  --text: #15171c;
  --muted: #5d6370;
  --line: #e2e3e6;
  --accent: #2459d6;
  --accent-ink: #ffffff;
  --accent-soft: #e8eefc;
  --highlight: #f2b73a;
  --shadow: 0 1px 2px rgb(0 0 0 / 0.05), 0 12px 32px rgb(0 0 0 / 0.08);
  --radius: 14px;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0f1114;
    --surface: #171a1f;
    --text: #eceef2;
    --muted: #9ca3b0;
    --line: #2a2e36;
    --accent: #6d97ff;
    --accent-ink: #0b0d10;
    --accent-soft: #1c2640;
    --shadow: 0 1px 2px rgb(0 0 0 / 0.4), 0 12px 32px rgb(0 0 0 / 0.35);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.65 -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Hiragino Sans", "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 4px; }
.wrap { max-width: 68rem; margin: 0 auto; padding: 0 1rem; }

/* Header */
.top {
  position: sticky; top: 0; z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: saturate(1.4) blur(12px);
  -webkit-backdrop-filter: saturate(1.4) blur(12px);
  border-bottom: 1px solid var(--line);
}
.top .wrap { display: flex; align-items: center; gap: 1.25rem; height: 3.5rem; }
.brand { display: flex; align-items: center; gap: 0.55rem; font-weight: 700; color: var(--text); text-decoration: none; letter-spacing: -0.01em; }
.brand img { width: 28px; height: 28px; }
.top nav { display: flex; gap: 1.25rem; margin-left: auto; font-size: 0.92rem; }
.top nav a { color: var(--muted); text-decoration: none; }
.top nav a:hover { color: var(--text); }
.lang { font-size: 0.85rem; color: var(--muted); text-decoration: none; border: 1px solid var(--line); border-radius: 999px; padding: 0.15rem 0.7rem; }
.lang:hover { color: var(--text); border-color: var(--muted); }
@media (max-width: 44rem) { .top nav { display: none; } .lang { margin-left: auto; } }

/* Buttons */
.button {
  display: inline-flex; align-items: center; gap: 0.5rem;
  background: var(--accent); color: var(--accent-ink);
  font-weight: 600; text-decoration: none;
  padding: 0.8rem 1.4rem; border-radius: 12px;
}
.button:hover { filter: brightness(1.07); }
.button svg { width: 1.1em; height: 1.1em; }
.button.small { padding: 0.4rem 0.9rem; font-size: 0.9rem; border-radius: 9px; }
.link { font-weight: 600; text-decoration: none; }
.link:hover { text-decoration: underline; }

/* Hero */
.hero { text-align: center; padding: 4rem 0 2.5rem; }
.hero h1 { font-size: clamp(2.1rem, 5.4vw, 3.4rem); line-height: 1.12; letter-spacing: -0.025em; margin: 0 auto 1rem; max-width: 18em; }
.hero h1 em { font-style: normal; color: var(--accent); }
.hero .lead { color: var(--muted); font-size: clamp(1.05rem, 2.2vw, 1.2rem); max-width: 36em; margin: 0 auto 2rem; }
.actions { display: flex; flex-wrap: wrap; justify-content: center; align-items: center; gap: 0.75rem 1.5rem; }
.req { color: var(--muted); font-size: 0.85rem; margin: 0.9rem 0 0; }

/* Before / after demo */
.demo { margin: 1rem auto 0; max-width: 60rem; }
.window {
  background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); overflow: hidden;
}
.window .chrome { display: flex; gap: 6px; padding: 10px 12px; border-bottom: 1px solid var(--line); }
.window .chrome span { width: 11px; height: 11px; border-radius: 50%; background: var(--line); }
.compare { position: relative; --split: 50%; touch-action: pan-y; user-select: none; }
.compare img { display: block; width: 100%; height: auto; }
.compare .after { position: absolute; inset: 0; clip-path: inset(0 0 0 var(--split)); }
.compare .handle {
  position: absolute; top: 0; bottom: 0; left: var(--split); width: 2px; margin-left: -1px;
  background: var(--accent); pointer-events: none;
}
.compare .handle::after {
  content: "‹ ›"; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);
  background: var(--accent); color: var(--accent-ink); font-weight: 700; font-size: 0.9rem; line-height: 1;
  padding: 0.45rem 0.55rem; border-radius: 999px; letter-spacing: 0.1em; box-shadow: var(--shadow);
}
.compare input {
  position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: ew-resize;
}
.compare .tag {
  position: absolute; bottom: 0.7rem; font-size: 0.75rem; font-weight: 600; padding: 0.2rem 0.55rem; border-radius: 6px;
  background: rgb(0 0 0 / 0.65); color: #fff; pointer-events: none;
}
.compare .tag.before { left: 0.7rem; }
.compare .tag.after-tag { right: 0.7rem; background: var(--accent); color: var(--accent-ink); }
.compare:has(input:focus-visible) .handle::after { outline: 2px solid var(--text); outline-offset: 2px; }
.caption { color: var(--muted); font-size: 0.85rem; text-align: center; margin: 0.8rem 0 0; }

/* Sections */
section { padding: 3.5rem 0 1rem; scroll-margin-top: 4rem; }
section > .wrap > h2, .section-title { font-size: clamp(1.5rem, 3.2vw, 2rem); letter-spacing: -0.02em; line-height: 1.2; margin: 0 0 0.6rem; }
.section-lead { color: var(--muted); margin: 0 0 1.8rem; max-width: 40em; }
.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; }
@media (max-width: 56rem) { .grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 36rem) { .grid { grid-template-columns: 1fr; } }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.3rem 1.3rem 1.4rem; }
.card .icon {
  width: 2.3rem; height: 2.3rem; border-radius: 10px; display: grid; place-items: center;
  background: var(--accent-soft); color: var(--accent); margin-bottom: 0.8rem;
}
.card .icon svg { width: 1.3rem; height: 1.3rem; }
.card h3 { font-size: 1.05rem; margin: 0 0 0.35rem; letter-spacing: -0.01em; }
.card p { margin: 0; color: var(--muted); font-size: 0.95rem; line-height: 1.6; }

.steps { list-style: none; padding: 0; margin: 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem; counter-reset: step; }
@media (max-width: 48rem) { .steps { grid-template-columns: 1fr; } }
.steps li { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.2rem 1.3rem; counter-increment: step; }
.steps li::before {
  content: counter(step); display: inline-grid; place-items: center; width: 1.8rem; height: 1.8rem; border-radius: 50%;
  background: var(--accent); color: var(--accent-ink); font-weight: 700; font-size: 0.9rem; margin-bottom: 0.7rem;
}
.steps h3 { font-size: 1.02rem; margin: 0 0 0.3rem; }
.steps p { margin: 0; color: var(--muted); font-size: 0.95rem; }
kbd {
  font: inherit; font-size: 0.88em; font-weight: 600; border: 1px solid var(--line); border-bottom-width: 2px;
  border-radius: 6px; padding: 0.05rem 0.4rem; background: var(--surface); color: var(--text);
}

.first-launch { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 1.6rem; }
.first-launch ol { margin: 0; padding-left: 1.3rem; }
.first-launch li { margin: 0 0 0.7rem; }
.first-launch li:last-child { margin-bottom: 0; }
.note { color: var(--muted); font-size: 0.92rem; margin: 1.2rem 0 0; }

.faq details { border-bottom: 1px solid var(--line); padding: 1rem 0; }
.faq details:first-of-type { border-top: 1px solid var(--line); }
.faq summary { cursor: pointer; font-weight: 600; list-style: none; display: flex; justify-content: space-between; gap: 1rem; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; color: var(--muted); font-weight: 400; font-size: 1.3rem; line-height: 1; }
.faq details[open] summary::after { content: "−"; }
.faq details p { color: var(--muted); margin: 0.6rem 0 0; max-width: 46em; }

.cta { text-align: center; padding: 4rem 0 2rem; }
.cta h2 { margin-bottom: 1.4rem; }

footer { border-top: 1px solid var(--line); margin-top: 3rem; padding: 1.8rem 0 2.5rem; color: var(--muted); font-size: 0.88rem; }
footer .wrap { display: flex; flex-wrap: wrap; gap: 0.6rem 1.5rem; align-items: center; }
footer a { color: inherit; }
footer .spacer { margin-left: auto; }
@media (max-width: 36rem) { footer .spacer { margin-left: 0; } }