:root {
  --bg0: #070a12;
  --bg1: #0e1526;
  --card: rgba(18, 24, 42, 0.78);
  --stroke: rgba(255, 255, 255, 0.08);
  --text: #edf2ff;
  --muted: #9aa6c2;
  --accent: #7c9cff;
  --accent-2: #5ef0c8;
  --danger: #ff8fab;
  --shadow: 0 24px 80px rgba(0, 0, 0, 0.45);
  --radius: 22px;
  --font: "SF Pro Display", "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: var(--font);
  color: var(--text);
  background: var(--bg0);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

.bg {
  position: fixed;
  inset: 0;
  background:
    radial-gradient(900px 500px at 10% -10%, rgba(124, 156, 255, 0.28), transparent 60%),
    radial-gradient(700px 420px at 90% 0%, rgba(94, 240, 200, 0.16), transparent 55%),
    radial-gradient(600px 500px at 50% 110%, rgba(255, 143, 171, 0.12), transparent 50%),
    linear-gradient(180deg, var(--bg0), var(--bg1));
  pointer-events: none;
  z-index: 0;
}

.shell {
  position: relative;
  z-index: 1;
  width: min(720px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2.5rem 0 3.5rem;
}

.hero { margin-bottom: 1.5rem; }
.eyebrow {
  display: inline-flex;
  gap: 0.4rem;
  margin: 0 0 0.75rem;
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--stroke);
  background: rgba(255,255,255,0.03);
  color: var(--accent-2);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
h1 {
  margin: 0 0 0.55rem;
  font-size: clamp(1.9rem, 5vw, 2.6rem);
  letter-spacing: -0.03em;
  line-height: 1.15;
}
.lede {
  margin: 0;
  color: var(--muted);
  font-size: 1.02rem;
  max-width: 38rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--stroke);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
  padding: 1.15rem 1.2rem 1.25rem;
  margin-bottom: 1rem;
}
.card-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.75rem;
}
.card-head label,
.card-head h2 {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 600;
}
.meta-row { display: flex; align-items: center; gap: 0.5rem; }

.chip {
  font-size: 0.75rem;
  color: var(--text);
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--stroke);
  border-radius: 999px;
  padding: 0.22rem 0.65rem;
  white-space: nowrap;
}
.chip.muted { color: var(--muted); }

select {
  appearance: none;
  background: rgba(255,255,255,0.06);
  color: var(--text);
  border: 1px solid var(--stroke);
  border-radius: 999px;
  padding: 0.28rem 1.7rem 0.28rem 0.7rem;
  font: inherit;
  font-size: 0.75rem;
  background-image: linear-gradient(45deg, transparent 50%, var(--muted) 50%),
    linear-gradient(135deg, var(--muted) 50%, transparent 50%);
  background-position: calc(100% - 12px) 55%, calc(100% - 7px) 55%;
  background-size: 5px 5px, 5px 5px;
  background-repeat: no-repeat;
}
select:focus { outline: 2px solid rgba(124,156,255,0.55); outline-offset: 2px; }

textarea {
  width: 100%;
  resize: vertical;
  min-height: 8rem;
  border-radius: 16px;
  border: 1px solid var(--stroke);
  background: rgba(0,0,0,0.28);
  color: var(--text);
  padding: 0.95rem 1rem;
  font: inherit;
  font-size: 1rem;
  line-height: 1.45;
}
textarea::placeholder { color: #6f7b97; }
textarea:focus {
  outline: none;
  border-color: rgba(124,156,255,0.55);
  box-shadow: 0 0 0 4px rgba(124,156,255,0.15);
}

.actions {
  display: flex;
  gap: 0.65rem;
  justify-content: flex-end;
  margin-top: 0.9rem;
}
.btn {
  border: 0;
  border-radius: 999px;
  padding: 0.7rem 1.15rem;
  font: inherit;
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  transition: transform 0.15s ease, opacity 0.15s ease, background 0.15s ease;
}
.btn:active { transform: scale(0.98); }
.btn:disabled { opacity: 0.4; cursor: not-allowed; }
.btn.primary {
  color: #061018;
  background: linear-gradient(135deg, var(--accent-2), #8fd0ff 55%, var(--accent));
}
.btn.primary:not(:disabled):hover { filter: brightness(1.05); }
.btn.ghost {
  color: var(--text);
  background: rgba(255,255,255,0.06);
  border: 1px solid var(--stroke);
}
.btn.ghost:not(:disabled):hover { background: rgba(255,255,255,0.1); }

.preview .qr-stage {
  display: grid;
  place-items: center;
  min-height: 300px;
  border-radius: 18px;
  background:
    linear-gradient(180deg, rgba(255,255,255,0.03), rgba(255,255,255,0.01)),
    repeating-linear-gradient(0deg, transparent, transparent 11px, rgba(255,255,255,0.025) 12px),
    repeating-linear-gradient(90deg, transparent, transparent 11px, rgba(255,255,255,0.025) 12px);
  border: 1px dashed rgba(255,255,255,0.12);
  padding: 1.25rem;
  position: relative;
}
.qrcode {
  width: min(280px, 72vw);
  height: min(280px, 72vw);
  display: grid;
  place-items: center;
  background: #fff;
  border-radius: 18px;
  padding: 14px;
  box-shadow: 0 18px 40px rgba(0,0,0,0.35);
}
.qrcode:empty { display: none; }
.qrcode img, .qrcode canvas, .qrcode table {
  max-width: 100% !important;
  height: auto !important;
}
.hint {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
  text-align: center;
  position: absolute;
}
.hint.hidden { display: none; }

.privacy {
  margin-top: 1.25rem;
  color: var(--muted);
  font-size: 0.86rem;
  padding: 0 0.2rem;
}
.privacy strong { color: var(--text); font-weight: 600; }

.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0);
  white-space: nowrap; border: 0;
}

@media (max-width: 520px) {
  .shell { width: calc(100% - 1.25rem); padding-top: 1.6rem; }
  .actions { flex-direction: column-reverse; }
  .btn { width: 100%; }
  .card-head { align-items: flex-start; flex-wrap: wrap; }
}