:root {
  --bg: #0f1117;
  --surface: #1a1d27;
  --surface-2: #242836;
  --border: #2e3345;
  --text: #e8eaf0;
  --text-muted: #9aa3b5;
  --primary: #6c5ce7;
  --primary-hover: #5a4bd1;
  --success: #00b894;
  --danger: #ff6b6b;
  --radius: 12px;
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.35);
  --font: "Inter", system-ui, -apple-system, sans-serif;
}

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

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  min-height: 100vh;
}

.app {
  max-width: 880px;
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
}

/* Header */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 2rem;
  gap: 1rem;
  flex-wrap: wrap;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

.logo-icon {
  font-size: 2.2rem;
  background: linear-gradient(135deg, var(--primary), #a29bfe);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo h1 {
  font-size: 1.55rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}

.subtitle {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

.device-badge {
  background: var(--surface-2);
  border: 1px solid var(--border);
  padding: 0.4rem 0.85rem;
  border-radius: 999px;
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* Cards */
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.5rem;
  margin-bottom: 1.25rem;
  box-shadow: var(--shadow);
}

.card h2 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 1.1rem;
  color: var(--text);
}

/* Dropzone */
.dropzone {
  border: 2px dashed var(--border);
  border-radius: var(--radius);
  padding: 2.5rem 1.5rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  background: var(--surface-2);
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--primary);
  background: rgba(108, 92, 231, 0.08);
}

.drop-icon {
  font-size: 2rem;
  margin-bottom: 0.5rem;
  opacity: 0.7;
}

.dropzone p {
  color: var(--text-muted);
  font-size: 0.95rem;
}

.dropzone .hint {
  font-size: 0.8rem;
  margin-top: 0.3rem;
}

.file-name {
  margin-top: 0.75rem !important;
  color: var(--primary) !important;
  font-weight: 500;
}

/* Form */
.form-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.1rem;
}

@media (max-width: 640px) {
  .form-grid {
    grid-template-columns: 1fr;
  }
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.form-group label {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-muted);
}

.form-group select,
.form-group input[type="text"] {
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.6rem 0.75rem;
  border-radius: 8px;
  font-size: 0.9rem;
  font-family: inherit;
  outline: none;
  transition: border-color 0.15s;
}

.form-group select:focus,
.form-group input:focus {
  border-color: var(--primary);
}

.form-group .hint {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.15rem;
}

.form-group code {
  background: var(--surface-2);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  font-size: 0.75rem;
}

.options-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  margin-top: 1.25rem;
}

.checkbox {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.9rem;
  color: var(--text-muted);
  cursor: pointer;
}

.checkbox input {
  accent-color: var(--primary);
  width: 1.05rem;
  height: 1.05rem;
}

/* Buttons */
.actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.7rem 1.4rem;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 600;
  font-family: inherit;
  border: none;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s, transform 0.1s;
}

.btn:active {
  transform: scale(0.98);
}

.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn.primary {
  background: var(--primary);
  color: #fff;
}

.btn.primary:hover:not(:disabled) {
  background: var(--primary-hover);
}

.btn.secondary {
  background: var(--surface-2);
  color: var(--text);
  border: 1px solid var(--border);
}

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

.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.spinner.hidden {
  display: none;
}

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

/* Status */
.status-message {
  font-size: 0.95rem;
  margin-bottom: 0.75rem;
  color: var(--text-muted);
}

.progress-bar {
  height: 6px;
  background: var(--surface-2);
  border-radius: 999px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, var(--primary), #a29bfe);
  border-radius: 999px;
  transition: width 0.3s ease;
}

/* Results */
.results-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-bottom: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-muted);
}

.results-meta span {
  background: var(--surface-2);
  padding: 0.3rem 0.7rem;
  border-radius: 6px;
}

.stems-list {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.stem-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.75rem 1rem;
}

.stem-name {
  font-weight: 500;
  text-transform: capitalize;
}

.stem-item a {
  color: var(--primary);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
}

.stem-item a:hover {
  text-decoration: underline;
}

/* Footer */
.footer {
  text-align: center;
  margin-top: 2.5rem;
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer a {
  color: var(--primary);
  text-decoration: none;
}

.footer a:hover {
  text-decoration: underline;
}

.hidden {
  display: none !important;
}

/* Error state */
.error-text {
  color: var(--danger);
}