:root{
  --bg: #f6f8fb;
  --card: #ffffff;
  --text: #0f1724;
  --muted: #5b6470;
  --accent: linear-gradient(135deg,#6d5df6 0%, #00c2ff 100%);
  --glass: rgba(255,255,255,0.6);
  --radius: 14px;
}
[data-theme="dark"]{
  --bg: #0b1020;
  --card: #0f1724;
  --text: #e6eef9;
  --muted: #9aa6b2;
  --glass: rgba(255,255,255,0.04);
}

html,body{height:100%}
body{
  margin:0;
  font-family: 'Inter', system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
  background: radial-gradient(1200px 400px at 10% 10%, rgba(109,93,246,0.08), transparent),
              radial-gradient(1000px 300px at 95% 90%, rgba(0,194,255,0.04), transparent),
              var(--bg);
  color:var(--text);
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  padding:24px;
  box-sizing:border-box;
  transition:background .3s, color .3s;
}

/* Header */
.header{
  max-width:1100px;
  margin:0 auto 18px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:16px;
}
.brand{
  display:flex;
  align-items:center;
  gap:12px;
}
.logo{
  width:48px;height:48px;border-radius:10px;
  background:var(--accent);
  box-shadow:0 6px 18px rgba(13, 27, 56, 0.08);
  display:grid;place-items:center;color:white;font-weight:700;
}
h1.title{margin:0;font-size:18px}
p.subtitle{margin:0;font-size:13px;color:var(--muted)}

.controls{
  display:flex;
  align-items:center;
  gap:12px;
}

/* Toggle */
.toggle{
  display:inline-flex;
  align-items:center;
  gap:8px;
  background:var(--glass);
  padding:6px;border-radius:999px;
  backdrop-filter: blur(6px);
}
.switch{
  width:44px;height:26px;border-radius:999px;background:#cbd5e1;position:relative;
  cursor:pointer;
}
.switch .dot{
  width:18px;height:18px;border-radius:50%;background:white;position:absolute;top:4px;left:4px;
  transition:left .25s;
  box-shadow:0 4px 10px rgba(2,6,23,0.12);
}
[data-theme="dark"] .switch{background:#223241}
[data-theme="dark"] .switch .dot{left:22px}

/* Layout */
.container{
  max-width:1100px;
  margin:0 auto;
  display:grid;
  grid-template-columns: 1fr 420px;
  gap:20px;
  align-items:start;
}
@media (max-width:980px){
  .container{grid-template-columns:1fr; padding-bottom:30px}
}

/* Left card */
.card{
  background:var(--card);
  border-radius:var(--radius);
  padding:22px;
  box-shadow:0 10px 30px rgba(11,20,40,0.06);
}
.hero{
  display:flex;
  flex-direction:column;
  gap:14px;
  padding-bottom:8px;
}
.hero h2{margin:0;font-size:28px}
.hero p{margin:0;color:var(--muted)}

.input-row{
  display:flex;
  gap:10px;
  margin-top:6px;
  align-items:center;
  flex-wrap:wrap;
}
input[type="text"], select{
  flex:1;
  padding:12px 14px;
  border-radius:10px;
  border:1px solid rgba(15,23,36,0.06);
  outline:none;
  font-size:14px;
  background:transparent;
  color:var(--text);
}
input[type="file"]{font-size:13px}
.btn{
  background:linear-gradient(90deg,#6d5df6,#00c2ff);
  color:white;padding:10px 14px;border-radius:10px;border:0;cursor:pointer;
  font-weight:600;transition:transform .12s,opacity .12s;
  box-shadow:0 8px 24px rgba(109,93,246,0.14);
}
.btn:active{transform:translateY(1px)}
.muted-small{font-size:13px;color:var(--muted)}

.settings{
  display:flex;
  gap:12px;
  margin-top:12px;
  flex-wrap:wrap;
  align-items:center;
}
.setting{
  background:var(--glass);
  padding:10px;border-radius:10px;
  min-width:120px;
  display:flex;gap:8px;align-items:center;flex-direction:column;
}
.color-row{display:flex;gap:8px;align-items:center}
.color-input{width:38px;height:32px;border-radius:8px;border:0;padding:0}

/* Right preview */
.preview-wrap{
  display:flex;flex-direction:column;gap:12px;align-items:center;
}
.qr-card{
  width:100%;
  max-width:360px;
  display:grid;
  place-items:center;
  padding:18px;
  border-radius:12px;
  background: linear-gradient(180deg, rgba(255,255,255,0.4), rgba(255,255,255,0.2));
  position:relative;
}
[data-theme="dark"] .qr-card{background: linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.01));}

.qr-canvas{
  border-radius:8px;
  background: var(--card);
  padding:10px;
  display:inline-block;
}
.logo-preview{position:absolute;bottom:12px;right:12px;background:var(--glass);padding:8px;border-radius:8px;font-size:12px;color:var(--muted)}

.action-row{display:flex;gap:8px;width:100%;justify-content:center;flex-wrap:wrap}
.secondary{background:transparent;border:1px solid rgba(15,23,36,0.06);padding:10px 12px;border-radius:10px;cursor:pointer}

/* About & FAQ */
.meta{
  display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:14px;
}
@media (max-width:640px){ .meta{grid-template-columns:repeat(1,1fr)} }
.meta .card-mini{padding:12px;border-radius:12px;background:var(--glass);text-align:center}
.faq{margin-top:14px}
.accordion{border-radius:10px;overflow:hidden}
.accordion-item{border-bottom:1px solid rgba(15,23,36,0.04)}
.accordion-button{width:100%;text-align:left;padding:12px 14px;background:transparent;border:0;display:flex;justify-content:space-between;align-items:center;cursor:pointer;color:var(--text)}
.accordion-content{padding:12px 14px;background:transparent;color:var(--text);display:none}

.footer{
  max-width:1100px;margin:18px auto 0;text-align:center;color:var(--muted);font-size:13px;
}

/* Preview modal */
.modal{
  position:fixed;inset:0;display:none;align-items:center;justify-content:center;background:rgba(2,6,23,0.5);z-index:999;
}
.modal .modal-card{background:var(--card);padding:20px;border-radius:12px;max-width:90%;width:480px}
.modal img{max-width:100%;height:auto;border-radius:10px}

/* small helpers */
.small{font-size:13px}
.muted{color:var(--muted)}
.center{text-align:center}