:root{
  --bg:#313F55;
  --card:#3c4c66;
  --muted:#9fb3d1;
  --text:#eaf1ff;
  --accent:#ffb359;
  --danger:#ff6b6b;
  --ok:#22c55e;
  --blue:#3fa9f5;
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace;
}

/* Base */
*{box-sizing:border-box}
html,body{height:100%}
body{
  margin:0;
  background:var(--bg);
  color:var(--text);
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}
body,button,input,textarea,label,h1,h2,h3,h4,h5,h6{font-family:Arial, sans-serif}

.wrap{max-width:1520px; margin:0 auto; padding:24px}

/* Header */
header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 12px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 30px;
}
.brand .logo {
  width: 160px;
  object-fit: contain;
}
.titleblock h1 {
  margin: 0;
  font-size: 1.8rem;
}
.titleblock .subtitle {
  margin: 2px 0 0 0;
  font-size: 0.95rem;
  opacity: 0.8;
}
h1 {
  margin: 0;
  font-size: clamp(24px, 2.2vw, 30px);
  letter-spacing: .2px;
  font-family: Arial, sans-serif;
  font-weight: 400;
}
.subtitle{color:var(--muted); margin:.25rem 0 0; font-size:16px}
main {
  margin-top: 32px;
}

/* Cards & layout */
.grid{
  display:grid;
  gap:16px;
  grid-template-columns: repeat(3, minmax(420px, 1fr));
}
.card{
  background:linear-gradient(180deg, rgba(255,255,255,.06), rgba(255,255,255,.03));
  border:1px solid rgba(255,255,255,.08);
  border-radius:16px;
  box-shadow:0 10px 30px rgba(0,0,0,.25);
}
.card .in{padding:18px}

/* Form */
label{display:block; font-size:15px; color:var(--muted); margin-bottom:8px}
textarea,input[type="number"]{
  border:1px solid rgba(255,255,255,.15);
  background:rgba(0,0,0,.18);
  color:var(--text);
  border-radius:12px;
  padding:12px 14px;
  font-size:16px;
  outline:none;
  transition:border .2s, box-shadow .2s, opacity .15s;
}
textarea{
  min-height:500px;
  max-height:70vh;
  overflow:auto;
  resize:vertical;
  font-family:var(--mono);
  line-height:1.45;
  width:100%;
}
input[type="number"]{width:100px}
:focus-visible{outline:3px solid rgba(255,179,89,.6); outline-offset:2px}
textarea:focus-visible,input:focus-visible{
  border-color:var(--accent);
  box-shadow:0 0 0 3px rgba(255,179,89,.25);
}
fieldset {
  border: none;
  padding: 0;
  margin: 0;
}
legend {
  padding: 0;
}

/* Toolbar & helpers */
.toolbar{display:flex; gap:12px; align-items:end; margin:6px 0 10px}
.stack > * + *{margin-top:12px}
.control{display:grid; gap:2px}
.hidden{display:none !important}
.visually-hidden{
  position:absolute !important;
  height:1px; width:1px;
  overflow:hidden; clip:rect(1px,1px,1px,1px);
  white-space:nowrap; clip-path:inset(50%);
}

/* Buttons */
button{
  appearance:none;
  cursor:pointer;
  border:none;
  padding:11px 14px;
  border-radius:12px;
  box-shadow:0 6px 20px rgba(0,0,0,.3);
  transition:transform .06s ease-in-out, filter .15s ease-in-out, opacity .15s;
  font-size:16px;
}
button:hover{filter:saturate(1.05) brightness(1.03)}
button:active{transform:translateY(1px)}
.btn-primary{background:linear-gradient(135deg,#D27328,#c9611f); color:#fff}
.btn-secondary{
  background:rgba(0,0,0,.18);
  color:#fff;
  border:1px solid rgba(255,255,255,.15);
  box-shadow:none;
}
button:disabled,[aria-disabled="true"]{
  opacity:.55;
  cursor:not-allowed;
  box-shadow:none;
  filter:none;
}

/* Messages */
.note{font-size:14px; color:var(--muted)}
.error{color:var(--danger); font-size:15px; margin-top:6px}
.ok{color:var(--ok); font-size:15px; margin-top:6px}
.section-title{font-size:clamp(18px,1.6vw,22px); margin-bottom:8px; margin-top:4px}

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

/* Download area */
.download-top{
  display:flex;
  align-items:center;
  gap:14px;
}
.central-toggle{
  display:flex;
  align-items:center;
  gap:8px;
  font-size:14px;
  color:var(--muted);
  user-select:none;
}
.central-toggle input{ width:16px; height:16px; }