:root {
  --bg: #0f172a;
  --card: #1e293b;
  --border: #334155;
  --text: #e2e8f0;
  --muted: #94a3b8;
  --accent: #38bdf8;
  --accent-hover: #0ea5e9;
  --success-bg: #14532d;
  --success-border: #22c55e;
  --error-bg: #4c1d1d;
  --error-border: #ef4444;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  padding: 2rem 1rem;
}

.container {
  width: 100%;
  max-width: 640px;
}

.header {
  text-align: center;
  margin-bottom: 1.5rem;
}

.brand {
  font-size: 2.75rem;
  letter-spacing: 0.15em;
  margin: 0;
  color: var(--accent);
}

.subtitle {
  margin: 0.25rem 0 0;
  color: var(--muted);
  font-size: 1.1rem;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
}

.dropzone {
  display: block;
  border: 2px dashed var(--border);
  border-radius: 10px;
  padding: 2.5rem 1rem;
  text-align: center;
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.dropzone:hover,
.dropzone:focus-visible,
.dropzone.dragover {
  border-color: var(--accent);
  background: rgba(56, 189, 248, 0.06);
  outline: none;
}

.dropzone-primary {
  font-size: 1.15rem;
  margin: 0 0 0.25rem;
}

.dropzone-secondary {
  color: var(--muted);
  margin: 0;
}

.file-list {
  list-style: none;
  margin: 1rem 0 0;
  padding: 0;
}

.file-list li {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  margin-bottom: 0.4rem;
  font-size: 0.95rem;
}

.file-list .file-name {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-list .file-size {
  color: var(--muted);
  flex-shrink: 0;
}

.actions {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

.btn {
  flex: 1;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  background: var(--accent);
  color: #04222f;
  cursor: pointer;
  transition: background 0.15s ease;
}

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

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

.btn-secondary {
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--border);
  flex: 0 0 auto;
}

.btn-secondary:hover:not(:disabled) {
  background: rgba(148, 163, 184, 0.1);
}

.status {
  margin-top: 1.5rem;
  padding: 1rem 1.25rem;
  border-radius: 10px;
  border: 1px solid var(--border);
}

.status.success {
  background: var(--success-bg);
  border-color: var(--success-border);
}

.status.error {
  background: var(--error-bg);
  border-color: var(--error-border);
}

.status h2 {
  margin: 0 0 0.5rem;
  font-size: 1.2rem;
}

.status p {
  margin: 0.2rem 0;
}

.status ul {
  margin: 0.5rem 0 0;
  padding-left: 1.25rem;
  color: var(--muted);
}

.spinner {
  display: inline-block;
  width: 1rem;
  height: 1rem;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  vertical-align: middle;
  margin-right: 0.5rem;
}

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