:root {
  --bg: #0f172a;
  --panel: #0b2540;
  --accent: #2dd4bf;
  --text: #e2e8f0;
  --muted: #94a3b8;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "SF Pro Display", "Segoe UI", sans-serif;
  background: radial-gradient(circle at 10% 20%, #13315c, #0f172a 35%), radial-gradient(circle at 90% 10%, #1b2a4a, #0f172a 35%);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px;
}

.card {
  background: var(--panel);
  border-radius: 14px;
  padding: 28px;
  max-width: 760px;
  width: 100%;
  box-shadow: 0 25px 70px rgba(0,0,0,0.35);
  border: 1px solid rgba(255,255,255,0.05);
}

h1 {
  margin: 0 0 12px;
  font-size: 28px;
  letter-spacing: -0.5px;
}

p.lead {
  margin: 0 0 24px;
  color: var(--muted);
}

form {
  display: grid;
  gap: 16px;
}

label {
  font-weight: 600;
  margin-bottom: 6px;
  display: inline-block;
}

input[type="number"], input[type="file"] {
  width: 100%;
  padding: 12px;
  border-radius: 10px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.04);
  color: var(--text);
}

input[type="file"]::-webkit-file-upload-button {
  background: var(--accent);
  border: none;
  color: #0b1b2b;
  padding: 10px 14px;
  border-radius: 8px;
  font-weight: 700;
  margin-right: 12px;
  cursor: pointer;
}

button {
  background: var(--accent);
  color: #0b1b2b;
  border: none;
  padding: 12px 16px;
  border-radius: 10px;
  font-weight: 700;
  cursor: pointer;
  transition: transform 120ms ease, box-shadow 120ms ease;
  box-shadow: 0 12px 30px rgba(45, 212, 191, 0.25);
}

button:hover { transform: translateY(-1px); }
button:active { transform: translateY(0); }

.button {
  display: inline-block;
  text-decoration: none;
  background: var(--accent);
  color: #0b1b2b;
  padding: 12px 16px;
  border-radius: 10px;
  font-weight: 700;
  box-shadow: 0 12px 30px rgba(45, 212, 191, 0.25);
}

.status {
  padding: 12px 14px;
  border-radius: 10px;
  background: rgba(255,255,255,0.04);
  border: 1px solid rgba(255,255,255,0.08);
}

.error { color: #fca5a5; }

ul { padding-left: 16px; }

.hidden { display: none; }

.code-block {
  position: relative;
}

.copy-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  background: var(--accent);
  color: #0b1b2b;
  border: none;
  padding: 6px 10px;
  border-radius: 8px;
  font-weight: 700;
  cursor: pointer;
  font-size: 12px;
}

textarea {
  width: 100%;
  padding: 12px;
  border-radius: 10px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.04);
  color: var(--text);
  resize: vertical;
}

@media (max-width: 640px) {
  .card { padding: 22px; }
  h1 { font-size: 24px; }
}

.card {
  color: var(--text);
}

.progress-overlay {
  position: fixed;
  inset: 0;
  background: rgba(5, 10, 20, 0.75);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 999;
}

.progress-modal {
  background: var(--panel);
  padding: 22px;
  border-radius: 12px;
  width: min(560px, 90vw);
  border: 1px solid rgba(255,255,255,0.1);
  box-shadow: 0 15px 45px rgba(0,0,0,0.35);
}

.progress-bar {
  width: 100%;
  height: 12px;
  background: rgba(255,255,255,0.08);
  border-radius: 999px;
  overflow: hidden;
  margin: 12px 0 8px;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, #22d3ee, #2dd4bf);
  width: 0%;
  transition: width 200ms ease;
}

.progress-details {
  color: var(--muted);
  margin: 4px 0 0;
}