:root {
  --bg: #0b0f0f;
  --bg-2: #101616;
  --surface: #151c1c;
  --line: #243030;
  --line-strong: #344443;
  --ink: #ecf3f1;
  --ink-soft: #a7b5b2;
  --ink-faint: #76868a;
  --primary: #2dd4a7;
  --primary-bright: #7eeccb;
  --primary-ink: #04261d;
  --alert: #f43f5e;
  --late: #fb7185;
  --short: #60a5fa;
  --shape: #fbbf24;
  --ml: #e879f9;
  --gutter: clamp(20px, 5vw, 56px);
  --sans: "Pretendard Variable", Pretendard, "Apple SD Gothic Neo", "Malgun Gothic", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, Menlo, Consolas, monospace;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 76px; color-scheme: dark; -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.75;
  word-break: keep-all;
  overflow-wrap: anywhere;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, p, ol, ul, dl, dd, figure { margin: 0; padding: 0; }
ol, ul { list-style: none; }
img { display: block; max-width: 100%; height: auto; }
a { color: inherit; }
:focus-visible { outline: 2px solid var(--primary-bright); outline-offset: 3px; }

.wrap { max-width: 1180px; margin-inline: auto; padding-inline: var(--gutter); }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; z-index: 20; padding: 8px 14px; background: var(--primary); color: var(--primary-ink); }

.btn {
  display: inline-block;
  padding: 12px 24px;
  border: 1px solid var(--primary);
  border-radius: 8px;
  background: var(--primary);
  color: var(--primary-ink);
  font-weight: 600;
  text-decoration: none;
  transition: background .15s, border-color .15s;
}
.btn:hover { background: var(--primary-bright); border-color: var(--primary-bright); }
.btn-sm { padding: 6px 14px; font-size: 15px; white-space: nowrap; }
.btn-ghost { background: transparent; border-color: var(--line-strong); color: var(--ink); }
.btn-ghost:hover { background: var(--surface); border-color: var(--ink-faint); }
.btn-dark { background: var(--bg); border-color: var(--bg); color: var(--ink); }
.btn-dark:hover { background: #1c2626; border-color: #1c2626; }

.mast {
  position: sticky;
  top: 0;
  z-index: 10;
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--bg) 84%, transparent);
  backdrop-filter: blur(14px);
}
.mast-in { display: flex; align-items: center; gap: 28px; min-height: 60px; }
.logo { display: flex; align-items: center; gap: 9px; font-weight: 700; font-size: 16px; text-decoration: none; white-space: nowrap; }
.logo small { color: var(--ink-faint); font-family: var(--mono); font-size: 11px; font-weight: 400; letter-spacing: 0.12em; }
.mast nav { display: flex; gap: 22px; margin-left: auto; font-size: 15px; white-space: nowrap; }
.mast nav a { color: var(--ink-soft); text-decoration: none; }
.mast nav a:hover { color: var(--ink); }

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.08fr);
  gap: clamp(32px, 4vw, 64px);
  align-items: center;
  padding: clamp(48px, 7vw, 96px) 0 clamp(48px, 7vw, 96px) max(var(--gutter), calc((100vw - 1180px) / 2 + var(--gutter)));
  background:
    radial-gradient(60% 80% at 92% 40%, rgba(45, 212, 167, 0.14), transparent 70%),
    var(--bg);
}
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chips li { padding: 2px 12px; border: 1px solid var(--line-strong); border-radius: 999px; color: var(--primary-bright); font-size: 14px; }
.hero h1 { margin-top: 22px; font-size: clamp(36px, 4.7vw, 64px); line-height: 1.2; letter-spacing: -0.03em; font-weight: 800; }
.hero em { color: var(--primary); font-style: normal; }
.lead { margin-top: 22px; color: var(--ink-soft); font-size: clamp(17px, 1.4vw, 19px); }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 30px; }

.hero-shot { position: relative; overflow: hidden; border: 1px solid var(--line-strong); border-right: 0; border-radius: 14px 0 0 14px; box-shadow: 0 30px 80px -30px rgba(45, 212, 167, 0.3); }
.hero-shot video { display: block; width: 100%; height: auto; }
.hero-toggle { position: absolute; left: 12px; bottom: 12px; padding: 6px 12px; border: 1px solid var(--line-strong); border-radius: 8px; background: rgba(0, 0, 0, 0.7); color: #fff; font: inherit; font-size: 13px; cursor: pointer; }
.hero-toggle:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; }

.facts { border-block: 1px solid var(--line); background: var(--bg-2); }
.facts dl { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; padding-block: 22px; }
.facts dt { color: var(--primary-bright); font-family: var(--mono); font-size: 13px; }
.facts dd { font-size: 16px; font-weight: 500; }

.strip svg { display: block; width: 100%; height: clamp(190px, 18vw, 260px); }
.strip figcaption { display: flex; justify-content: space-between; gap: 16px; padding-block: 10px 14px; color: var(--ink-faint); font-size: 13px; }

.trace { fill: none; stroke: var(--primary); stroke-width: 1; stroke-opacity: 0.72; vector-effect: non-scaling-stroke; }
.trace-flag { fill: none; stroke: var(--alert); stroke-width: 1.2; vector-effect: non-scaling-stroke; }
.band { fill: var(--alert); opacity: 0.12; }
.tick { stroke: var(--line-strong); stroke-width: 1; vector-effect: non-scaling-stroke; }
.tick-flag { stroke: var(--alert); }
.note { fill: var(--alert); font-family: var(--sans); font-size: 17px; font-weight: 700; }
.note-num { fill: var(--alert); font-family: var(--mono); font-size: 14px; }

@media (prefers-reduced-motion: no-preference) {
  .draw { stroke-dasharray: 1; stroke-dashoffset: 1; animation: pen 2.4s cubic-bezier(.4, 0, .3, 1) forwards; }
  .late-in { opacity: 0; animation: appear .4s 1.5s forwards; }
  .band.late-in { animation-name: appear-band; }
  @keyframes pen { to { stroke-dashoffset: 0; } }
  @keyframes appear { to { opacity: 1; } }
  @keyframes appear-band { to { opacity: 0.12; } }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

.chapter { padding-block: clamp(64px, 8vw, 112px); border-top: 1px solid var(--line); }
.tint { background: var(--bg-2); }
.grid { display: grid; grid-template-columns: minmax(0, 4fr) minmax(0, 8fr); gap: clamp(32px, 5vw, 72px); align-items: start; }
.rail { position: sticky; top: 92px; }
.no { color: var(--primary); font-family: var(--mono); font-size: 14px; }
.rail h2 { margin-top: 6px; font-size: clamp(26px, 2.8vw, 36px); line-height: 1.3; letter-spacing: -0.025em; font-weight: 700; }
.rail p { margin-top: 14px; color: var(--ink-soft); font-size: 16px; }

.shot + .shot { margin-top: 28px; }
.shot img { width: 100%; border: 1px solid var(--line-strong); border-radius: 10px; }
.shot figcaption { margin-top: 10px; color: var(--ink-soft); font-size: 15px; }
.shot b { margin-right: 8px; color: var(--ink); }
.ticks { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-top: 28px; color: var(--ink-soft); font-size: 15px; }
.ticks li { padding-top: 12px; border-top: 1px solid var(--line-strong); }
.ticks b { display: block; color: var(--ink); font-size: 16px; }

.steps { counter-reset: step; border-left: 1px solid var(--line-strong); }
.steps li { position: relative; padding: 0 0 32px 32px; counter-increment: step; }
.steps li:last-child { padding-bottom: 0; }
.steps li::before {
  content: counter(step);
  position: absolute;
  left: -14px;
  top: 2px;
  width: 27px;
  height: 27px;
  border-radius: 50%;
  background: var(--primary);
  color: var(--primary-ink);
  font-family: var(--mono);
  font-size: 13px;
  font-weight: 500;
  line-height: 27px;
  text-align: center;
}
.steps h3, .cards h3 { font-size: 19px; line-height: 1.45; }
.steps p, .cards p { margin-top: 4px; color: var(--ink-soft); font-size: 16px; }

.cards { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.cards article { padding: 22px; border: 1px solid var(--line); border-radius: 10px; background: var(--bg); }

table { width: 100%; border-collapse: collapse; font-size: 16px; }
th, td { padding: 14px 14px 14px 0; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
thead th { border-bottom-color: var(--line-strong); color: var(--ink-faint); font-size: 14px; font-weight: 500; }
tbody th { font-weight: 700; white-space: nowrap; }
tbody td { color: var(--ink-soft); }
table i { display: inline-block; width: 9px; height: 9px; margin-right: 10px; border-radius: 50%; }
.c-late { background: var(--late); }
.c-short { background: var(--short); }
.c-shape { background: var(--shape); }
.c-ml { background: var(--ml); }

.stats { display: grid; grid-template-columns: 1fr 1fr; border-top: 1px solid var(--line-strong); border-left: 1px solid var(--line-strong); }
.stats > div { padding: 24px; border-right: 1px solid var(--line-strong); border-bottom: 1px solid var(--line-strong); }
.stats dt { color: var(--ink-soft); font-size: 15px; }
.stats dd { color: var(--primary); font-family: var(--mono); font-size: clamp(36px, 4.4vw, 54px); font-weight: 500; line-height: 1.25; letter-spacing: -0.03em; }
.stats small { margin-left: 5px; color: var(--ink-soft); font-family: var(--sans); font-size: 16px; font-weight: 400; letter-spacing: 0; }

.faq details { border-bottom: 1px solid var(--line); }
.faq details:first-child { border-top: 1px solid var(--line); }
.faq summary { padding: 16px 28px 16px 0; font-weight: 600; cursor: pointer; list-style: none; position: relative; }
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; position: absolute; right: 4px; color: var(--primary); font-family: var(--mono); }
.faq details[open] summary::after { content: "−"; }
.faq p { padding-bottom: 18px; color: var(--ink-soft); font-size: 16px; }

.closing { padding-block: clamp(56px, 7vw, 88px); background: var(--primary); color: var(--primary-ink); }
.closing h2 { font-size: clamp(26px, 3.2vw, 40px); line-height: 1.3; letter-spacing: -0.025em; }
.closing p { margin: 12px 0 26px; max-width: 40em; }

footer { border-top: 1px solid var(--line); color: var(--ink-faint); font-size: 14px; }
.foot { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 8px 24px; padding-block: 22px; }

.missing { min-height: 100vh; padding: clamp(48px, 10vw, 120px) var(--gutter); }
.missing .kicker { color: var(--primary); font-family: var(--mono); font-size: 14px; }
.missing h1 { margin: 12px 0 28px; font-size: clamp(28px, 5vw, 56px); line-height: 1.25; }

@media (max-width: 1080px) {
  .mast nav { display: none; }
  .mast-in { justify-content: space-between; }
}

@media (max-width: 900px) {
  .hero { grid-template-columns: minmax(0, 1fr); padding-right: var(--gutter); }
  .hero-shot { border-right: 1px solid var(--line-strong); border-radius: 12px; }
  .facts dl { grid-template-columns: 1fr 1fr; }
  .grid { grid-template-columns: minmax(0, 1fr); }
  .rail { position: static; }
}

@media (max-width: 560px) {
  .logo small { display: none; }
  .cards, .ticks { grid-template-columns: 1fr; }
  .strip figcaption { flex-direction: column; gap: 0; }
  table, tbody, tr, tbody th, tbody td { display: block; }
  thead { display: none; }
  tbody tr { padding: 14px 0; border-bottom: 1px solid var(--line); }
  tbody th, tbody td { padding: 0; border: 0; }
}