:root {
  color-scheme: light;
  --bg: #f5f7fb;
  --panel: rgba(255, 255, 255, 0.88);
  --border: rgba(15, 23, 42, 0.12);
  --text: #0f172a;
  --muted: #64748b;
  --accent: #2563eb;
  --accent-weak: #dbeafe;
  --shadow: 0 18px 40px rgba(15, 23, 42, 0.09);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, #dbeafe 0, transparent 35%),
    radial-gradient(circle at top right, #e0e7ff 0, transparent 30%),
    var(--bg);
}

.shell {
  width: min(1100px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 3rem;
}

.hero {
  margin-bottom: 1.25rem;
}

.eyebrow {
  margin: 0 0 .35rem;
  text-transform: uppercase;
  letter-spacing: .14em;
  color: var(--accent);
  font-size: .82rem;
  font-weight: 700;
}

h1, h2, p {
  margin-top: 0;
}

h1 {
  margin-bottom: .5rem;
  font-size: clamp(2rem, 4vw, 3.25rem);
}

.lead {
  max-width: 60ch;
  color: var(--muted);
  font-size: 1.05rem;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.controls {
  padding: 1rem;
  display: grid;
  gap: 1rem;
  margin-bottom: 1rem;
}

.field {
  display: grid;
  gap: .45rem;
  font-weight: 600;
}

.field span {
  font-size: .95rem;
}

input {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: .9rem 1rem;
  font: inherit;
  background: white;
  color: var(--text);
}

input:focus,
button:focus {
  outline: 3px solid rgba(37, 99, 235, 0.2);
  outline-offset: 2px;
}

.actions {
  display: flex;
  flex-wrap: wrap;
  gap: .75rem;
}

button {
  appearance: none;
  border: 0;
  border-radius: 999px;
  padding: .85rem 1.15rem;
  background: var(--accent);
  color: white;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
}

button.secondary {
  background: var(--accent-weak);
  color: var(--accent);
}

button:hover {
  transform: translateY(-1px);
}

.status {
  min-height: 1.5em;
  margin: 0;
  color: var(--muted);
}

.layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: 1rem;
}

.sidebar,
.content {
  padding: 1rem;
}

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: .9rem;
}

.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 2.5rem;
  padding: .35rem .7rem;
  border-radius: 999px;
  background: var(--accent-weak);
  color: var(--accent);
  font-size: .9rem;
  font-weight: 700;
}

.pill-soft {
  background: #ecfeff;
  color: #0f766e;
}

.muted {
  color: var(--muted);
}

.names {
  display: grid;
  gap: .6rem;
}

.name-button {
  width: 100%;
  text-align: left;
  border-radius: 16px;
  padding: .9rem 1rem;
  background: white;
  color: var(--text);
  border: 1px solid var(--border);
}

.name-button[aria-pressed="true"] {
  border-color: rgba(37, 99, 235, 0.35);
  background: linear-gradient(180deg, #eff6ff 0%, #ffffff 100%);
}

.file-view {
  min-height: 28rem;
  margin: 0;
  padding: 1rem;
  border-radius: 16px;
  border: 1px solid var(--border);
  background: #0b1220;
  color: #e2e8f0;
  overflow: auto;
  white-space: pre-wrap;
  line-height: 1.6;
}

@media (max-width: 860px) {
  .layout {
    grid-template-columns: 1fr;
  }
}