:root {
  --primary: #4f46e5;
  --primary-hover: #4338ca;
  --bg: #f8fafc;
  --card-bg: #ffffff;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --border: #e2e8f0;
  --danger: #ef4444;
  --success: #10b981;
}

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

body {
  font-family: 'Inter', system-ui, -apple-system, sans-serif;
  background-color: var(--bg);
  color: var(--text-main);
  line-height: 1.5;
  min-height: 100vh;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem 1rem;
}

header {
  margin-bottom: 2rem;
  text-align: center;
}

.logo-section {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

h1 {
  font-size: 1.875rem;
  font-weight: 600;
  color: var(--text-main);
}

.subtitle {
  color: var(--text-muted);
  font-size: 0.875rem;
  font-family: monospace;
}

.state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 2rem;
  text-align: center;
  gap: 1rem;
}

.hidden {
  display: none !important;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

.file-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.5rem;
  list-style: none;
}

.file-card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.file-card:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

.file-info {
  margin-bottom: 1.5rem;
}

.file-name {
  font-weight: 500;
  font-size: 1rem;
  color: var(--text-main);
  word-break: break-all;
  margin-bottom: 0.25rem;
}

.file-meta {
  font-size: 0.75rem;
  color: var(--text-muted);
  display: flex;
  gap: 0.75rem;
}

.btn-download {
  background-color: var(--primary);
  color: white;
  border: none;
  padding: 0.625rem 1rem;
  border-radius: 0.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  transition: background-color 0.2s;
  width: 100%;
}

.btn-download:hover {
  background-color: var(--primary-hover);
}

.btn-download:disabled {
  background-color: var(--text-muted);
  cursor: not-allowed;
  opacity: 0.7;
}

.btn-secondary {
  background-color: white;
  border: 1px solid var(--border);
  padding: 0.5rem 1rem;
  border-radius: 0.375rem;
  cursor: pointer;
}

footer {
  margin-top: 4rem;
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-muted);
}