:root{
  --bg:#ffffff; --soft:#f6f7f9; --ink:#0d1117; --muted:#5b6573;
  --line:#e6e8ec; --accent:#2563eb; --accent2:#0ea5e9; --dark:#0b1220;
  --radius:16px; --shadow:0 10px 30px rgba(15,23,42,.08);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;color:var(--ink);background:var(--bg);
  font-family:"Noto Sans JP",system-ui,-apple-system,"Hiragino Kaku Gothic ProN",sans-serif;
  line-height:1.7;-webkit-font-smoothing:antialiased;
}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
.wrap{max-width:1120px;margin:0 auto;padding:0 24px}

/* nav */
.nav{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.86);
  backdrop-filter:saturate(180%) blur(12px);border-bottom:1px solid var(--line)}
.nav .wrap{display:flex;align-items:center;justify-content:space-between;height:64px}
.brand{font-weight:800;letter-spacing:.02em;font-size:18px}
.brand span{color:var(--accent)}
.nav .links{display:flex;gap:28px;font-size:14px;font-weight:500}
.nav .links a{color:var(--muted)}
.nav .links a:hover,.nav .links a.active{color:var(--ink)}

/* hero */
.hero{background:radial-gradient(1200px 500px at 70% -10%,#1e293b 0%,var(--dark) 60%);
  color:#fff;padding:96px 0 88px}
.hero h1{font-size:clamp(30px,5vw,52px);line-height:1.25;margin:0 0 18px;font-weight:800;letter-spacing:.01em}
.hero p{font-size:clamp(15px,2vw,19px);color:#c5cdd9;max-width:640px;margin:0 0 32px}
.hero .pill{display:inline-block;font-size:12px;font-weight:600;letter-spacing:.08em;
  color:#bfdbfe;background:rgba(37,99,235,.18);border:1px solid rgba(37,99,235,.4);
  padding:6px 14px;border-radius:999px;margin-bottom:22px}
.btn{display:inline-block;background:var(--accent);color:#fff;font-weight:700;
  padding:14px 26px;border-radius:12px;font-size:15px;transition:.2s}
.btn:hover{background:#1d4ed8;transform:translateY(-1px)}
.btn.ghost{background:transparent;border:1px solid rgba(255,255,255,.3);margin-left:10px}
.btn.ghost:hover{background:rgba(255,255,255,.08)}

/* sections */
section{padding:80px 0}
.sec-head{text-align:center;max-width:680px;margin:0 auto 48px}
.sec-head .k{font-size:12px;font-weight:700;letter-spacing:.14em;color:var(--accent);text-transform:uppercase}
.sec-head h2{font-size:clamp(24px,3.4vw,36px);margin:10px 0 12px;font-weight:800}
.sec-head p{color:var(--muted);margin:0}
.alt{background:var(--soft)}

/* before-after */
.ba-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:28px}
@media(max-width:760px){.ba-grid{grid-template-columns:1fr}}
.card{background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  overflow:hidden;box-shadow:var(--shadow)}
.ba{position:relative;overflow:hidden;user-select:none;background:#eef1f5}
.ba-img{width:100%;display:block}
.ba-before{position:absolute;top:0;left:0;width:100%;height:100%;object-fit:cover}
.ba-divider{position:absolute;top:0;bottom:0;left:50%;width:2px;background:#fff;
  box-shadow:0 0 0 1px rgba(0,0,0,.15);pointer-events:none}
.ba-divider::after{content:"⟺";position:absolute;top:50%;left:50%;transform:translate(-50%,-50%);
  width:38px;height:38px;border-radius:50%;background:#fff;color:var(--accent);
  display:flex;align-items:center;justify-content:center;font-size:16px;box-shadow:var(--shadow)}
.ba-range{position:absolute;inset:0;width:100%;height:100%;margin:0;opacity:0;cursor:ew-resize}
.ba-tag{position:absolute;top:12px;font-size:11px;font-weight:700;letter-spacing:.08em;
  color:#fff;background:rgba(13,17,23,.6);padding:4px 10px;border-radius:999px;pointer-events:none}
.ba-tag-l{left:12px}.ba-tag-r{right:12px;background:rgba(37,99,235,.85)}
.card .cap{padding:16px 18px}
.card .cap h3{margin:0 0 4px;font-size:16px;font-weight:700}
.card .cap p{margin:0;font-size:13px;color:var(--muted)}
.card .cap .badge{display:inline-block;font-size:11px;font-weight:600;color:var(--accent);
  background:#eff4ff;border:1px solid #dbe7ff;padding:2px 8px;border-radius:999px;margin-top:8px}

/* variants */
.var-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
@media(max-width:860px){.var-grid{grid-template-columns:repeat(2,1fr)}}
.var{border:1px solid var(--line);border-radius:12px;overflow:hidden;background:#fff;box-shadow:var(--shadow)}
.var img{width:100%;aspect-ratio:3/2;object-fit:contain;background:#fff}
.var span{display:block;text-align:center;font-size:12px;font-weight:600;padding:8px;color:var(--muted)}

/* steps (pipeline) */
.steps{display:grid;grid-template-columns:repeat(2,1fr);gap:20px;margin-top:36px}
@media(max-width:760px){.steps{grid-template-columns:1fr}}
.step{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.step .n{display:inline-flex;align-items:center;justify-content:center;width:34px;height:34px;
  border-radius:10px;background:var(--accent);color:#fff;font-weight:800;margin-bottom:12px}
.step h3{margin:0 0 6px;font-size:17px}
.step p{margin:0;color:var(--muted);font-size:14px}
.step .tool{display:inline-block;margin-top:10px;font-size:11px;color:#475569;background:var(--soft);
  border:1px solid var(--line);padding:3px 9px;border-radius:999px}
.diagram{background:var(--soft);border:1px solid var(--line);border-radius:var(--radius);
  padding:32px 28px;box-shadow:var(--shadow)}

/* flow diagram (vertical pipeline) */
.vflow{max-width:720px;margin:0 auto;display:flex;flex-direction:column;align-items:center}
.vterm{display:inline-flex;align-items:baseline;gap:10px;background:var(--dark);color:#fff;
  border-radius:999px;padding:13px 26px;font-weight:800;font-size:16px;box-shadow:var(--shadow)}
.vterm.out{background:var(--accent)}
.vterm small{font-weight:600;font-size:12px;color:#c5cdd9}
.vterm.out small{color:#dbeafe}
.vnode{width:100%;background:#fff;border:1px solid var(--line);border-radius:14px;
  padding:15px 18px;box-shadow:var(--shadow);display:flex;gap:14px;align-items:flex-start;text-align:left}
.vnode .num{flex:0 0 auto;display:inline-flex;align-items:center;justify-content:center;
  width:30px;height:30px;border-radius:9px;background:var(--accent);color:#fff;font-weight:800;font-size:14px}
.vnode .bd{flex:1;min-width:0}
.vnode .bd .t{margin:0;font-weight:700;font-size:15px;line-height:1.4}
.vnode .bd .cond{display:inline-block;font-size:11px;font-weight:600;color:#92400e;background:#fffbeb;
  border:1px solid #fde68a;border-radius:999px;padding:1px 9px;margin-left:8px;white-space:nowrap}
.vnode .tools{display:flex;flex-wrap:wrap;align-items:center;gap:6px;margin-top:9px}
.vnode .tools .tg{font-size:11.5px;font-weight:600;color:#334155;background:var(--soft);
  border:1px solid var(--line);border-radius:7px;padding:3px 9px;
  font-family:ui-monospace,SFMono-Regular,Menlo,monospace}
.vnode .tools .arr{color:var(--muted);font-size:12px;font-weight:700}
.vconn{width:2px;height:20px;background:#cbd5e1;position:relative}
.vconn::after{content:"";position:absolute;left:50%;bottom:-1px;transform:translateX(-50%);
  border-left:5px solid transparent;border-right:5px solid transparent;border-top:7px solid #cbd5e1}
.vconn.derive{width:0;background:transparent;border-left:2px dashed #93b4f5;height:26px}
.vconn.derive::after{border-top-color:#93b4f5}
.derive-cap{font-size:11px;font-weight:600;letter-spacing:.04em;color:var(--accent);margin:2px 0 8px}
.vnode.derive{border:1px dashed var(--accent);background:#f5f9ff}
.vnode.derive .num{background:var(--accent2)}
.vnode.derive .vars{display:flex;flex-wrap:wrap;gap:6px;margin-top:9px}
.vnode.derive .vars span{font-size:11px;font-weight:600;color:var(--accent);background:#fff;
  border:1px solid #dbe7ff;border-radius:999px;padding:3px 10px}
@media(max-width:560px){
  .vnode{flex-direction:column;gap:8px}
  .vnode .bd .cond{margin-left:0;margin-top:4px}
}
.note{margin-top:28px;background:#fffbeb;border:1px solid #fde68a;color:#78350f;
  border-radius:12px;padding:16px 20px;font-size:14px}

/* footer */
footer{background:var(--dark);color:#9aa4b2;padding:48px 0;font-size:13px}
footer .wrap{display:flex;justify-content:space-between;flex-wrap:wrap;gap:16px}
footer a{color:#cbd5e1}
.center{text-align:center}
.mt{margin-top:40px}