:root{
  --bg:#ffffff;
  --card:#ffffff;
  --ink:#111827;
  --muted:#6b7280;
  --accent:#6557A2;
  --grid:rgba(17,24,39,.12);
}

*{box-sizing:border-box}
html,body{
  margin:0;
  padding:0;
  background:var(--bg);
  color:var(--ink);
  font:15px/1.5 system-ui,-apple-system,Segoe UI,Roboto,Arial,sans-serif;
}

/* Layout with two cards */
main{
  max-width:1680px;
  margin:16px auto 48px;
  padding:0 16px;
  display:grid;
  gap:16px;
  grid-template-columns:minmax(420px,0.8fr) 1fr;
  align-items:start;
}
@media (max-width:900px){
  main{grid-template-columns:1fr}
}

/* Cards */
.card{
  background:var(--card);
  border:1px solid var(--grid);
  border-radius:16px;
  padding:14px;
  box-shadow:0 8px 24px rgba(0,0,0,.06);
  position:relative;
}
.card::before{
  content:"";
  position:absolute;
  inset:0 0 auto 0;
  height:4px;
  border-top-left-radius:16px;
  border-top-right-radius:16px;
  background:var(--accent);
  opacity:.85;
}
.card-data{background:#f8f7ff}
.card-result{background:#f9fff8;padding:8px}

h2{
  margin:0 0 12px;
  font-size:20px;
  color:var(--ink);
}

/* Controls */
.row{
  display:flex;
  gap:10px;
  align-items:center;
  margin-top:10px;
  flex-wrap:wrap;
}
.row.wrap-gap{gap:8px 10px}

.top-inputs{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(140px,max-content));
  gap:8px;
  align-items:end;
}

label{
  display:block;
  font-size:12px;
  margin-bottom:3px;
  color:#374151;
}

button,
input[type="number"],
input[type="text"],
select{
  background:#fff;
  color:var(--ink);
  border:1px solid var(--grid);
  border-radius:10px;
  padding:7px 8px;
  font-size:13px;
}
select{min-width:120px}
button{
  cursor:pointer;
  transition:border-color .15s,box-shadow .15s,transform .02s;
}
button:hover{
  border-color:var(--accent);
  box-shadow:0 0 0 3px rgba(101,87,162,.18);
}
button:active{transform:translateY(.5px)}
.btn-primary{
  background:var(--accent);
  color:#fff;
  border-color:var(--accent);
}
.btn-outline{
  background:#fff;
  color:var(--accent);
  border-color:var(--accent);
}

/* Textarea */
.row-textarea{
  margin-top:10px;
}
#bulkInput{
  width:100%;
  min-height:260px;
  padding:8px 10px;
  border-radius:10px;
  border:1px solid var(--grid);
  font-family:ui-monospace,Consolas,Menlo,monospace;
  font-size:12.5px;
  resize:vertical;
}

/* Hide number spinners */
input[type=number]::-webkit-outer-spin-button,
input[type=number]::-webkit-inner-spin-button{
  -webkit-appearance:none;
  margin:0;
}
input[type=number]{-moz-appearance:textfield}

/* Plot area responsive */
.plot{
  position:relative;
  min-height:320px;
  height:clamp(300px,40vh,600px);
  background:#fff;
  border:1px solid var(--grid);
  border-radius:12px;
  display:grid;
  place-items:center;
  overflow:hidden;
  width:100%;
  margin:0;
}
.plot canvas{
  width:100%;
  height:100%;
  display:block;
}

/* Legend */
.legend{
  display:flex;
  gap:12px;
  align-items:center;
  color:var(--muted);
  margin-top:6px;
  font-size:12px;
}

.muted{color:var(--muted);font-size:12px}

/* Status & toasts */
.status-bar{
  margin-top:8px;
  font-size:12px;
  color:var(--muted);
  min-height:1.2em;
}

.toast-wrap{
  position:fixed;
  right:16px;
  bottom:16px;
  display:flex;
  flex-direction:column;
  gap:8px;
  z-index:9999;
}
.toast{
  background:#111827;
  color:#fff;
  border-radius:10px;
  padding:10px 12px;
  box-shadow:0 10px 30px rgba(0,0,0,.2);
  border:1px solid rgba(255,255,255,.08);
  display:flex;
  gap:10px;
  align-items:flex-start;
  max-width:420px;
  animation:slideIn .18s ease-out;
  font-size:12.5px;
}
.toast .title{font-weight:600;margin-right:6px}
.toast.warn{background:#78350f}
.toast.err{background:#7f1d1d}
.toast.ok{background:#065f46}
@keyframes slideIn{
  from{transform:translateY(10px);opacity:0}
  to{transform:translateY(0);opacity:1}
}

input[type=number]{width:80px;}