* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #0f0f0f;
  --surface: #1a1a2e;
  --surface2: #16213e;
  --accent: #6366f1;
  --accent-hover: #818cf8;
  --text: #e2e8f0;
  --text-dim: #94a3b8;
  --danger: #ef4444;
  --success: #22c55e;
  --radius: 12px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
}

.container {
  max-width: 640px;
  margin: 0 auto;
  padding: 24px 16px;
}

header {
  text-align: center;
  margin-bottom: 32px;
}

header h1 {
  font-size: 28px;
  font-weight: 700;
  background: linear-gradient(135deg, var(--accent), #a78bfa);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

header p {
  color: var(--text-dim);
  font-size: 14px;
  margin-top: 4px;
}

.input-group {
  display: flex;
  gap: 8px;
  margin-bottom: 16px;
}

.input-group input {
  flex: 1;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid #334155;
  border-radius: var(--radius);
  color: var(--text);
  font-size: 16px;
  outline: none;
  transition: border-color 0.2s;
}

.input-group input:focus {
  border-color: var(--accent);
}

.input-group input::placeholder {
  color: var(--text-dim);
}

.btn {
  padding: 14px 24px;
  background: var(--accent);
  color: white;
  border: none;
  border-radius: var(--radius);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
  white-space: nowrap;
}

.btn:hover {
  background: var(--accent-hover);
}

.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-sm {
  padding: 10px 20px;
  font-size: 14px;
}

.settings {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 24px;
}

.settings h3 {
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--text-dim);
  margin-bottom: 16px;
}

.settings-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.field label {
  display: block;
  font-size: 13px;
  color: var(--text-dim);
  margin-bottom: 6px;
}

.field select {
  width: 100%;
  padding: 10px 12px;
  background: var(--surface2);
  border: 1px solid #334155;
  border-radius: 8px;
  color: var(--text);
  font-size: 14px;
  outline: none;
  cursor: pointer;
}

.field select:focus {
  border-color: var(--accent);
}

.video-info {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 24px;
  display: none;
}

.video-info.visible {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.video-info img {
  width: 160px;
  border-radius: 8px;
  flex-shrink: 0;
}

.video-meta h2 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 4px;
  line-height: 1.3;
}

.video-meta p {
  font-size: 13px;
  color: var(--text-dim);
}

.download-section {
  display: none;
  text-align: center;
}

.download-section.visible {
  display: block;
}

.progress-bar {
  width: 100%;
  height: 8px;
  background: var(--surface2);
  border-radius: 4px;
  overflow: hidden;
  margin: 16px 0;
}

.progress-bar .fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), #a78bfa);
  border-radius: 4px;
  transition: width 0.3s ease;
  width: 0%;
}

.status-text {
  font-size: 14px;
  color: var(--text-dim);
  margin-bottom: 12px;
}

.status-text.error {
  color: var(--danger);
}

.status-text.success {
  color: var(--success);
}

.download-link {
  display: inline-block;
  padding: 12px 32px;
  background: var(--success);
  color: white;
  text-decoration: none;
  border-radius: var(--radius);
  font-weight: 600;
  margin-top: 8px;
  transition: opacity 0.2s;
}

.download-link:hover {
  opacity: 0.9;
}

.supported {
  text-align: center;
  margin-top: 48px;
  padding: 24px;
  border-top: 1px solid #1e293b;
}

.supported p {
  font-size: 13px;
  color: var(--text-dim);
}

.badges {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 8px;
}

.badge {
  padding: 4px 12px;
  background: var(--surface);
  border-radius: 20px;
  font-size: 12px;
  color: var(--text-dim);
}

.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid var(--text-dim);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
  vertical-align: middle;
  margin-right: 8px;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@media (max-width: 480px) {
  .settings-grid {
    grid-template-columns: 1fr;
  }
  .video-info.visible {
    flex-direction: column;
  }
  .video-info img {
    width: 100%;
  }
  .input-group {
    flex-direction: column;
  }
}