:root {
  --bg: #0f0f0d;
  --surface: #161614;
  --surface-2: #1d1d1a;
  --border: #2a2a26;
  --border-strong: #3d3d37;
  --text: #ecebe4;
  --muted: #9b9a90;
  --faint: #6c6b62;
  --accent: #c8a35a;
  --on-ink: #0f0f0d;
  --danger: #e5806b;
  --ok: #8fbf8a;
  --shadow: 0 1px 0 rgba(255, 255, 255, .03) inset, 0 30px 60px -40px rgba(0, 0, 0, .9);
  color-scheme: dark;
}

:root[data-theme="light"] {
  --bg: #f4f1ea;
  --surface: #fbfaf6;
  --surface-2: #efebe1;
  --border: #dedacd;
  --border-strong: #c3beae;
  --text: #17160f;
  --muted: #615f53;
  --faint: #8e8b7c;
  --accent: #8a6a2f;
  --on-ink: #f4f1ea;
  --danger: #b4452f;
  --ok: #3f7a45;
  --shadow: 0 1px 2px rgba(23, 22, 15, .04), 0 30px 60px -45px rgba(23, 22, 15, .35);
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
[hidden] { display: none !important; }
html { -webkit-text-size-adjust: 100%; }

body {
  min-height: 100vh;
  font-family: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  font-size: 15px;
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  transition: background .3s, color .3s;
}

.page { max-width: 1040px; margin: 0 auto; padding: 28px 24px 40px; }

/* top bar */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 22px;
  border-bottom: 1px solid var(--border);
}
.brand { display: flex; align-items: center; gap: 12px; }
.logo { width: 34px; height: 34px; display: block; }
.logo .l-bg { fill: var(--text); }
.logo .l-fg { fill: var(--on-ink); }
.logo .l-st { stroke: var(--on-ink); }
.logo .l-ac { fill: var(--accent); }
.brand-name { font-size: 15px; font-weight: 600; letter-spacing: -.01em; }

.theme-toggle {
  width: 38px;
  height: 38px;
  display: grid;
  place-items: center;
  color: var(--muted);
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 10px;
  cursor: pointer;
  transition: color .2s, border-color .2s;
}
.theme-toggle:hover { color: var(--text); border-color: var(--border-strong); }
.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .sun { display: none; }
:root[data-theme="light"] .theme-toggle .sun { display: block; }
:root[data-theme="light"] .theme-toggle .moon { display: none; }

/* hero */
.hero { padding: 64px 0 48px; max-width: 640px; }
.kicker {
  font-size: 12px;
  font-weight: 600;
  letter-spacing: .14em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 18px;
}
h1 {
  font-family: "Bricolage Grotesque", "Inter", sans-serif;
  font-weight: 700;
  font-size: clamp(2rem, 8vw, 4rem);
  line-height: 1.05;
  letter-spacing: -.035em;
  margin-bottom: 20px;
}
h1 { white-space: nowrap; }
h1 em { font-style: normal; color: var(--accent); }
.subtitle { color: var(--muted); font-size: 1.05rem; max-width: 460px; }

/* card */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.tabs { display: flex; padding: 0 28px; border-bottom: 1px solid var(--border); }
.tab {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 18px 4px;
  margin-right: 28px;
  font-size: 14px;
  font-weight: 500;
  color: var(--muted);
  background: none;
  border: 0;
  border-bottom: 2px solid transparent;
  margin-bottom: -1px;
  cursor: pointer;
  transition: color .2s, border-color .2s;
}
.tab svg { width: 16px; height: 16px; flex: none; }
.tab:hover { color: var(--text); }
.tab.active { color: var(--text); border-bottom-color: var(--text); }
.tab:focus-visible, .btn:focus-visible, .theme-toggle:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.content {
  display: grid;
  grid-template-columns: 1fr 1px 1fr;
  gap: 40px;
  padding: 36px 28px 40px;
}
.divider { background: var(--border); }
@media (max-width: 820px) {
  .content { grid-template-columns: 1fr; gap: 32px; padding: 28px 20px; }
  .divider { display: none; }
  .tabs { padding: 0 20px; }
  .hero { padding: 44px 0 32px; }
}

h2 {
  font-family: "Bricolage Grotesque", "Inter", sans-serif;
  font-weight: 500;
  font-size: 1.5rem;
  letter-spacing: -.02em;
  line-height: 1.2;
  margin-bottom: 22px;
}

/* form */
.stack { display: flex; flex-direction: column; gap: 18px; }
.row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
label { display: block; font-size: 13px; font-weight: 500; color: var(--muted); margin-bottom: 7px; }
input, textarea {
  width: 100%;
  padding: 12px 14px;
  font-size: 15px;
  color: var(--text);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  transition: border-color .2s, box-shadow .2s;
}
input::placeholder, textarea::placeholder { color: var(--faint); }
input:hover, textarea:hover { border-color: var(--border-strong); }
input:focus, textarea:focus {
  outline: none;
  border-color: var(--text);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 28%, transparent);
}
textarea { resize: none; }
.hint { font-size: 12.5px; color: var(--faint); margin-top: 8px; }

/* buttons */
.btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  background: transparent;
  border: 1px solid var(--border-strong);
  border-radius: 10px;
  cursor: pointer;
  transition: background .2s, border-color .2s, transform .15s;
}
.btn:hover { background: var(--surface-2); }
.btn:active { transform: translateY(1px); }
.btn svg { width: 16px; height: 16px; }
.btn.primary { color: var(--on-ink); background: var(--text); border-color: var(--text); }
.btn.primary:hover { background: var(--text); opacity: .88; }
.btn.ghost { border-color: transparent; color: var(--muted); align-self: flex-start; padding-left: 0; }
.btn.ghost:hover { background: none; color: var(--text); }
#check-icon { color: var(--ok); }

/* result */
.result-col { display: flex; flex-direction: column; align-items: center; }
.result-col h2 { align-self: flex-start; }
.stage {
  width: 100%;
  max-width: 340px;
  padding: 20px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 14px;
}
.qr-frame {
  padding: 14px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 10px;
  animation: rise .3s ease-out;
}
@keyframes rise { from { opacity: 0; transform: translateY(6px); } }
#qr { width: 100%; height: auto; display: block; }
.scan-note { text-align: center; font-size: 13px; color: var(--muted); margin-top: 14px; }
.error { text-align: center; font-size: 13px; color: var(--danger); margin-top: 12px; }

.empty { text-align: center; padding: 56px 12px; color: var(--faint); font-size: 14px; }
.empty svg { width: 48px; height: 48px; margin: 0 auto 14px; color: var(--border-strong); }

.actions { display: flex; gap: 10px; width: 100%; max-width: 340px; margin-top: 18px; }
.actions .btn { flex: 1; }

.data-box { width: 100%; max-width: 340px; margin-top: 22px; }
.data-box h3 {
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--faint);
  margin-bottom: 8px;
}
.data-box .code {
  max-height: 120px;
  overflow-y: auto;
  padding: 12px 14px;
  font-size: 12px;
  color: var(--muted);
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 10px;
}
.data-box pre { white-space: pre-wrap; overflow-wrap: anywhere; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }

/* footer */
.footer {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 8px 24px;
  margin-top: 36px;
  padding-top: 20px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  color: var(--faint);
}
.footer a { color: var(--muted); text-decoration: underline; text-decoration-color: var(--border-strong); text-underline-offset: 3px; transition: color .2s, text-decoration-color .2s; }
.footer a:hover { color: var(--text); text-decoration-color: var(--accent); }

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}