:root {
  --bg: #0a0a0a;
  --bg-2: #0f0f0e;
  --panel: #141413;
  --line: #222120;
  --line-2: #2e2d2b;
  --text: #ecebe8;
  --muted: #8e8b85;
  --dim: #5f5d59;
  --accent: #d6d3cc;
  --accent-ink: #121211;
  --danger: #b98378;
  --radius: 18px;
  --sans: "Pretendard", "Pretendard Variable", -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", "Segoe UI", system-ui, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", "JetBrains Mono", Consolas, monospace;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 17px;
  line-height: 1.65;
  word-break: keep-all;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
code, pre { font-family: var(--mono); }
::selection { background: var(--accent); color: var(--accent-ink); }

.skip { position: absolute; left: -9999px; top: 8px; background: var(--accent); color: var(--accent-ink); padding: 8px 14px; border-radius: 8px; z-index: 100; }
.skip:focus { left: 8px; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }

.container { width: min(1160px, 100% - 40px); margin-inline: auto; }
.container.narrow { width: min(780px, 100% - 40px); }
.muted { color: var(--muted); }

/* ---------- Nav ---------- */
.nav {
  position: fixed; inset: 0 0 auto 0; z-index: 50;
  display: flex; align-items: center; justify-content: space-between; gap: 20px;
  padding: 14px max(20px, calc((100% - 1160px) / 2));
  background: color-mix(in srgb, var(--bg) 70%, transparent);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  border-bottom: 1px solid transparent;
  transition: border-color .3s;
}
.nav.scrolled { border-bottom-color: var(--line); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; font-size: 20px; letter-spacing: -0.02em; }
.brand b { color: var(--muted); font-weight: 700; }
.brand-mark { width: 28px; height: 28px; }
.nav-links { display: flex; gap: 30px; font-size: 15px; color: var(--muted); }
.nav-links a { transition: color .2s; }
.nav-links a:hover { color: var(--text); }

/* ---------- Buttons ---------- */
.btn {
  --h: 52px;
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  height: var(--h); padding: 0 24px;
  border-radius: 999px; border: 1px solid var(--line-2);
  background: transparent; color: var(--text);
  font: 600 16px/1 var(--sans); cursor: pointer;
  transition: background .3s, border-color .3s, color .3s;
}
.btn svg { width: 16px; height: 16px; }
.btn-sm { --h: 38px; padding: 0 16px; font-size: 14px; }
.btn-primary { background: var(--accent); color: var(--accent-ink); border-color: var(--accent); }
.btn-primary:hover:not(:disabled) { background: var(--text); border-color: var(--text); }
.btn-ghost:hover, .nav .btn:hover { border-color: var(--text); }
.btn:disabled { cursor: not-allowed; background: transparent; color: var(--muted); border: 1px dashed var(--line-2); }

/* ---------- Hero ---------- */
.hero {
  position: relative; min-height: 100svh;
  display: flex; flex-direction: column; justify-content: center;
  padding: 120px 0 0; overflow: hidden;
  isolation: isolate;
}
.hero::before {
  content: ""; position: absolute; z-index: -1;
  width: 900px; height: 900px; left: 50%; top: -320px; transform: translateX(-50%);
  background: radial-gradient(closest-side, color-mix(in srgb, var(--accent) 5%, transparent) 0%, transparent 100%);
  filter: blur(40px);
}
.hero-grid { position: absolute; inset: 0; z-index: -2; width: 100%; height: 100%; opacity: .4; }
.hero-inner { width: min(1000px, 100% - 40px); margin: 0 auto; text-align: center; }
.eyebrow {
  display: inline-flex; align-items: center; gap: 10px;
  padding: 7px 14px; border: 1px solid var(--line-2); border-radius: 999px;
  font-size: 13px; color: var(--muted); margin: 0 0 28px;
  background: color-mix(in srgb, var(--panel) 60%, transparent);
}
.dot { width: 6px; height: 6px; border-radius: 50%; background: var(--accent); animation: breathe 4s ease-in-out infinite; }
@keyframes breathe { 50% { opacity: .35; } }

.hero-title {
  margin: 0; font-weight: 800; letter-spacing: -0.045em; line-height: 1.08;
  font-size: clamp(42px, 7.6vw, 100px);
}
.hero-title span:first-child { color: var(--muted); font-weight: 700; }
.hero-title span { display: block; }
.strike { position: relative; display: inline-block !important; color: var(--text); }
.strike::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: .02em; height: 2px;
  background: color-mix(in srgb, var(--accent) 45%, transparent); transform-origin: left; transform: scaleX(0);
  animation: underline 2.2s 1s cubic-bezier(.4,0,.2,1) forwards;
}
@keyframes underline { to { transform: scaleX(1); } }
.hero-sub { margin: 28px auto 0; max-width: 640px; color: var(--muted); font-size: clamp(16px, 2vw, 19px); }

/* Alias demo */
.alias-demo {
  margin: 44px auto 0; max-width: 620px; text-align: left;
  background: linear-gradient(180deg, var(--panel), var(--bg-2));
  border: 1px solid var(--line-2); border-radius: var(--radius);
  box-shadow: 0 24px 60px -30px rgba(0,0,0,.7);
  overflow: hidden;
}
.alias-demo-head { display: flex; align-items: center; gap: 12px; padding: 12px 16px; border-bottom: 1px solid var(--line); font-size: 12px; color: var(--dim); }
.lights { display: inline-flex; gap: 6px; }
.lights i { width: 10px; height: 10px; border-radius: 50%; background: var(--line-2); }
.alias-row { padding: 22px 20px 6px; }
.alias-for { display: block; font-size: 13px; color: var(--muted); margin-bottom: 6px; }
.alias-addr { display: block; font-size: clamp(18px, 3.4vw, 24px); font-weight: 500; color: var(--text); overflow-wrap: anywhere; }
.alias-domain { color: var(--dim); }
.alias-actions { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; padding: 14px 20px 20px; }
.alias-note { font-size: 13px; color: var(--dim); margin-left: auto; }
#alias-copy.copied { border-color: var(--accent); color: var(--accent); }

.hero-cta { display: flex; flex-wrap: wrap; justify-content: center; gap: 12px; margin-top: 36px; }

.ticker { margin-top: 90px; border-block: 1px solid var(--line); overflow: hidden; background: var(--bg-2); }
.ticker-track { display: flex; width: max-content; animation: marquee 90s linear infinite; }
.ticker-track span { padding: 18px 28px; white-space: nowrap; font-size: 14px; color: var(--dim); font-weight: 500; }
.ticker-track span::after { content: "◆"; margin-left: 56px; color: var(--line-2); font-size: 10px; vertical-align: middle; }
@keyframes marquee { to { transform: translateX(-50%); } }

/* ---------- Sections ---------- */
.section { padding: clamp(90px, 13vw, 160px) 0; position: relative; }
.section-title { margin: 0 0 22px; font-size: clamp(34px, 5.4vw, 64px); line-height: 1.12; letter-spacing: -0.04em; font-weight: 800; }
.kicker { margin: 0 0 18px; font: 700 13px/1 var(--sans); text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.lead { color: var(--muted); font-size: clamp(16px, 1.8vw, 19px); max-width: 520px; margin: 0; }
.lead-wide { max-width: 640px; }

/* Pillars */
.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 56px; }
.card {
  --mx: 50%; --my: 50%;
  position: relative; padding: 34px 30px 36px;
  background: var(--panel); border: 1px solid var(--line); border-radius: var(--radius);
  overflow: hidden; transition: border-color .4s;
}
.card::before {
  content: ""; position: absolute; inset: 0; pointer-events: none; opacity: 0; transition: opacity .3s;
  background: radial-gradient(420px circle at var(--mx) var(--my), color-mix(in srgb, var(--accent) 4%, transparent), transparent 60%);
}
.card:hover { border-color: var(--line-2); }
.card:hover::before { opacity: 1; }
.card-icon { width: 52px; height: 52px; display: grid; place-items: center; border-radius: 14px; background: var(--bg-2); border: 1px solid var(--line-2); margin-bottom: 26px; }
.card-icon svg { width: 30px; height: 30px; }
.card h3 { margin: 0 0 10px; font-size: 22px; letter-spacing: -0.02em; }
.card p { margin: 0; color: var(--muted); font-size: 15.5px; }

/* Aliases */
.split { display: grid; grid-template-columns: 1fr 1fr; gap: 70px; align-items: center; }
.checks { list-style: none; padding: 0; margin: 32px 0 0; display: grid; gap: 14px; }
.checks li { position: relative; padding-left: 34px; }
.checks li::before {
  content: ""; position: absolute; left: 0; top: 4px; width: 20px; height: 20px; border-radius: 6px;
  background: transparent;
  border: 1px solid var(--line-2);
}
.checks li::after { content: ""; position: absolute; left: 7px; top: 8px; width: 6px; height: 10px; border: solid var(--accent); border-width: 0 2px 2px 0; transform: rotate(45deg); }
.tag { margin-left: 6px; font: 600 11px/1 var(--mono); padding: 4px 7px; border-radius: 6px; border: 1px solid var(--line-2); color: var(--muted); vertical-align: 2px; }

.flow {
  padding: 34px; border-radius: 24px; border: 1px solid var(--line);
  background: var(--bg-2);
}
.flow-node { display: grid; gap: 8px; }
.flow-label { font: 600 12px/1 var(--mono); color: var(--dim); text-transform: uppercase; letter-spacing: .1em; }
.flow-box {
  display: flex; align-items: center; gap: 12px; justify-content: space-between;
  padding: 16px 18px; border-radius: 14px; background: var(--panel); border: 1px solid var(--line-2);
  font: 500 15px/1.3 var(--mono); overflow-wrap: anywhere; transition: border-color .3s, opacity .3s;
}
.flow-alias { border-color: color-mix(in srgb, var(--accent) 35%, transparent); color: var(--text); }
.flow-inbox { justify-content: flex-start; color: var(--muted); }
.flow-inbox svg { width: 18px; height: 18px; flex: none; }
.flow-pipe { position: relative; height: 54px; margin-left: 28px; width: 2px; background: var(--line-2); overflow: hidden; transition: opacity .3s; }
.flow-pipe i { position: absolute; left: -1px; width: 4px; height: 18px; border-radius: 4px; background: color-mix(in srgb, var(--accent) 70%, transparent); animation: drip 3.2s ease-in-out infinite; }
.flow-pipe-2 i { animation-delay: 1.6s; }
@keyframes drip { from { top: -20px; } to { top: 60px; } }
.flow-status { margin: 22px 0 0; font-size: 14px; color: var(--muted); }
.flow-status::before { content: "●"; margin-right: 8px; color: var(--accent); }

.flow.is-off .flow-alias { border-color: color-mix(in srgb, var(--danger) 40%, transparent); color: var(--danger); text-decoration: line-through; }
.flow.is-off .flow-pipe-2 { opacity: .25; }
.flow.is-off .flow-pipe-2 i { animation: none; opacity: 0; }
.flow.is-off .flow-pipe:first-of-type i { background: var(--danger); }
.flow.is-off .flow-status::before { color: var(--danger); }

.switch { position: relative; flex: none; width: 46px; height: 26px; border-radius: 999px; border: 0; padding: 0; cursor: pointer; background: var(--line-2); transition: background .25s; }
.switch i { position: absolute; top: 3px; left: 3px; width: 20px; height: 20px; border-radius: 50%; background: var(--text); transition: transform .35s cubic-bezier(.4,0,.2,1); }
.switch.is-on { background: var(--accent); }
.switch.is-on i { transform: translateX(20px); background: var(--accent-ink); }

/* Security */
.security { background: linear-gradient(180deg, var(--bg), var(--bg-2) 30%, var(--bg)); }
.spec-grid { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 60px; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.spec { padding: 30px 28px 34px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); transition: background .3s; }
.spec:hover { background: var(--panel); }
.spec-k { display: block; font-size: 13px; color: var(--dim); margin-bottom: 6px; }
.spec-v { display: block; font-size: 22px; font-weight: 700; letter-spacing: -0.02em; margin-bottom: 10px; }
.spec p { margin: 0; color: var(--muted); font-size: 15px; }

.terminal { margin-top: 60px; border: 1px solid var(--line-2); border-radius: var(--radius); overflow: hidden; background: #050607; }
.terminal-head { display: flex; align-items: center; gap: 14px; padding: 12px 16px; border-bottom: 1px solid var(--line); font: 12px var(--mono); color: var(--dim); }
.terminal-body { margin: 0; padding: 26px 24px; font-size: clamp(11px, 1.4vw, 14px); line-height: 1.75; color: var(--dim); white-space: pre-wrap; word-break: break-all; min-height: 210px; }
.terminal-foot { margin: 0; padding: 14px 24px; border-top: 1px solid var(--line); font-size: 14px; color: var(--muted); }

/* Invite */
.invite-card {
  position: relative; overflow: hidden; isolation: isolate;
  padding: clamp(40px, 7vw, 84px); border-radius: 30px;
  background: var(--panel); border: 1px solid var(--line-2);
}
.invite-glow {
  position: absolute; z-index: -1; width: 700px; height: 700px; right: -260px; top: -320px;
  background: radial-gradient(closest-side, color-mix(in srgb, var(--accent) 6%, transparent), transparent);
  animation: float 20s ease-in-out infinite alternate;
}
@keyframes float { to { transform: translate(-40px, 30px); } }
.invite-card .lead { max-width: 620px; }
.invite-card strong { color: var(--text); }
.steps { list-style: none; padding: 0; margin: 50px 0 0; display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; }
.steps li { display: flex; gap: 16px; padding: 22px; border-radius: 16px; background: var(--bg-2); border: 1px solid var(--line); }
.step-n { font: 500 14px/1 var(--mono); color: var(--dim); padding-top: 4px; }
.steps h4 { margin: 0 0 4px; font-size: 18px; }
.steps p { margin: 0; color: var(--muted); font-size: 14.5px; }
.invite-cta { display: flex; flex-wrap: wrap; align-items: center; gap: 18px; margin-top: 44px; }
.invite-note { color: var(--dim); font-size: 14px; }

/* FAQ */
.faq-list { margin-top: 40px; border-top: 1px solid var(--line); }
.faq details { border-bottom: 1px solid var(--line); }
.faq summary {
  list-style: none; cursor: pointer; position: relative;
  padding: 26px 48px 26px 0; font-size: 18px; font-weight: 600; letter-spacing: -0.01em;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: ""; position: absolute; right: 6px; top: 50%; width: 12px; height: 12px; margin-top: -8px;
  border: solid var(--muted); border-width: 0 2px 2px 0; transform: rotate(45deg); transition: transform .3s, border-color .3s;
}
.faq details[open] summary::after { transform: rotate(225deg); margin-top: -2px; border-color: var(--accent); }
.faq details p { margin: -6px 0 26px; color: var(--muted); max-width: 680px; }

/* Footer */
.footer { border-top: 1px solid var(--line); padding: 44px 0 50px; }
.footer-inner { display: flex; flex-wrap: wrap; align-items: center; gap: 12px 28px; }
.footer-copy { margin: 0; font-size: 14px; color: var(--muted); }
.footer-copy:first-of-type { margin-left: auto; }

/* Reveal */
.reveal { opacity: 0; transform: translateY(10px); transition: opacity 1.2s ease, transform 1.2s ease; transition-delay: var(--d, 0s); }
.reveal.in { opacity: 1; transform: none; }
.no-js .reveal { opacity: 1; transform: none; }

/* Responsive */
@media (max-width: 960px) {
  .cards, .spec-grid, .steps { grid-template-columns: 1fr; }
  .split { grid-template-columns: 1fr; gap: 50px; }
  .nav-links { display: none; }
  .br-md { display: none; }
}
@media (max-width: 560px) {
  body { font-size: 16px; }
  .alias-note { margin-left: 0; width: 100%; }
  .footer-copy:first-of-type { margin-left: 0; }
  .flow { padding: 22px; }
  .hero-cta .btn { width: 100%; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
  html { scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; }
  .strike::after { transform: scaleX(1); }
}
.lead-center { margin: 0 auto 36px; }