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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #1a1a2e;
  color: #e0e0e0;
  padding: 20px;
}

.app {
  max-width: 800px;
  margin: 0 auto;
}

header {
  margin-bottom: 30px;
}

header h1 {
  color: #0078ff;
  font-size: 1.5rem;
}

section {
  background: #16213e;
  border-radius: 8px;
  padding: 20px;
  margin-bottom: 20px;
}

section h2 {
  font-size: 1.1rem;
  margin-bottom: 15px;
  color: #a0a0c0;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 15px;
  margin-bottom: 15px;
}

.card {
  background: #0f3460;
  border-radius: 6px;
  padding: 15px;
  text-align: center;
}

.card h3 {
  font-size: 0.85rem;
  color: #8888aa;
  margin-bottom: 8px;
}

.card p {
  font-size: 1.4rem;
  font-weight: bold;
  color: #0078ff;
}

button {
  background: #0078ff;
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 0.9rem;
  margin-right: 8px;
}

button:hover {
  background: #005fcc;
}

#usb-list {
  list-style: none;
  margin-top: 10px;
}

#usb-list li {
  padding: 8px;
  background: #0f3460;
  border-radius: 4px;
  margin-bottom: 5px;
  font-size: 0.85rem;
}

#file-result {
  margin-top: 10px;
  font-size: 0.85rem;
  color: #8888aa;
  word-break: break-all;
}

label {
  margin-right: 10px;
}

input[type="number"] {
  background: #0f3460;
  border: 1px solid #333;
  color: #e0e0e0;
  padding: 6px 10px;
  border-radius: 4px;
  margin-bottom: 10px;
}