:root {
  --bios-gray:   #c3c7cb;   /* main panel gray */
  --bios-dark:   #2b2f36;   /* header / text   */
  --bios-blue:   #0a3d91;   /* selection bar   */
  --bios-edge:   #7f8388;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  background: #6c7075;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: "Consolas", "Courier New", monospace;
  color: #111;
}

#bios {
  width: 760px;
  max-width: 95vw;
  background: var(--bios-gray);
  border: 2px solid #fff;
  outline: 2px solid var(--bios-edge);
  box-shadow: 6px 6px 0 rgba(0, 0, 0, .35);
}

#bios-header {
  background: var(--bios-dark);
  color: #e8ebf0;
  padding: 10px 14px;
  font-weight: bold;
  letter-spacing: .5px;
  border-bottom: 2px solid var(--bios-blue);
}

#bios-main { padding: 16px 18px; min-height: 240px; }
.panel-title { margin: 0 0 10px; font-weight: bold; }

#file-list { list-style: none; margin: 0; padding: 0; }
#file-list li {
  padding: 4px 10px;
  cursor: default;
  white-space: pre;
}
#file-list li.selected {
  background: var(--bios-blue);
  color: #fff;
}

#bios-footer {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 8px 14px;
  font-size: 13px;
  border-top: 2px solid var(--bios-edge);
  background: #b3b7bb;
}
#bios-footer .keys { color: #1a1d22; }