:root{
  --bg:#f4f7fb;
  --panel:#fff;
  --text:#0f172a;
  --muted:#64748b;
  --border:#e2e8f0;
  --accent:#0ea5a4;
  --accent2:#06b6d4;
  --shadow:0 18px 45px rgba(2,6,23,.12);
  --radius:16px;
}

*{box-sizing:border-box}

html,body{
  height:100%;
  overflow:hidden;
}

body{
  margin:0;
  font-family:Inter,system-ui,sans-serif;
  background:radial-gradient(1200px 600px at 15% 10%,rgba(14,165,164,.15),transparent 55%),var(--bg);
  display:flex;
  align-items:center;
  justify-content:center;
  padding:24px;
}

.shell{
  width:min(1040px,100%);
  height:min(680px,100%);
  background:var(--panel);
  border-radius:var(--radius);
  box-shadow:var(--shadow);
  display:flex;
  overflow:hidden;
}

.left{display:none;width:50%;position:relative}
@media(min-width:900px){.left{display:block}.right{width:50%}}

.left-bg{
  position:absolute;inset:0;
  background:linear-gradient(120deg,#0ea5a4,#06b6d4);
}

.left-inner{
  position:absolute;inset:0;
  display:flex;align-items:center;justify-content:center;
  padding:48px;color:#fff
}

.hero h2{font-size:40px;margin:0 0 10px}
.hero p{opacity:.9}

.right{
  width:100%;
  padding:40px;
  display:flex;
  flex-direction:column;
}

.tabs{display:flex;border-bottom:1px solid var(--border)}
.tab-btn{
  flex:1;padding:14px;
  background:none;border:0;
  font-weight:700;color:var(--muted);
  cursor:pointer
}
.tab-btn.active{color:var(--text)}

.tab-line{height:2px;background:linear-gradient(90deg,var(--accent),var(--accent2))}

.panel{flex:1;display:flex;flex-direction:column;justify-content:center}

label{font-size:12px;font-weight:700;margin-top:12px;display:block}

.input{
  width:100%;
  padding:11px;
  border:1px solid var(--border);
  border-radius:12px;
}

.field{position:relative}
.toggle{
  position:absolute;right:12px;top:50%;
  transform:translateY(-50%);
  font-size:12px;color:var(--accent);cursor:pointer
}

.row{
  display:flex;justify-content:space-between;
  margin-top:10px;font-size:12px
}

.btn{
  margin-top:16px;
  height:42px;border:0;border-radius:12px;
  background:linear-gradient(135deg,var(--accent),var(--accent2));
  color:#fff;font-weight:900;
}

.alert{
  background:#fff7ed;
  border:1px solid #fed7aa;
  padding:10px;border-radius:10px;
  font-size:13px;margin-bottom:12px
}

.helpbox{
  background:#f8fafc;
  border:1px solid var(--border);
  padding:16px;border-radius:12px
}

.hidden{display:none}