:root {
  --bg0: #071018;
  --bg1: #0d1f2d;
  --cyan: #3de7ff;
  --amber: #ffb347;
  --rose: #ff5c7a;
  --mint: #5dffb0;
  --ink: #e8f4ff;
  --muted: #8aa4b8;
  --panel: rgba(10, 28, 42, 0.88);
  --line: rgba(61, 231, 255, 0.28);
  --font-display: "Orbitron", sans-serif;
  --font-body: "Space Grotesk", sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(1200px 600px at 20% -10%, rgba(61, 231, 255, 0.12), transparent 55%),
    radial-gradient(900px 500px at 90% 10%, rgba(255, 179, 71, 0.08), transparent 50%),
    linear-gradient(180deg, var(--bg0), var(--bg1) 55%, #050b11);
  color: var(--ink);
  font-family: var(--font-body);
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    radial-gradient(1px 1px at 20% 30%, rgba(255,255,255,0.45), transparent),
    radial-gradient(1px 1px at 70% 60%, rgba(255,255,255,0.35), transparent),
    radial-gradient(1.5px 1.5px at 40% 80%, rgba(61,231,255,0.4), transparent),
    radial-gradient(1px 1px at 85% 25%, rgba(255,255,255,0.3), transparent);
  opacity: 0.7;
  animation: drift 40s linear infinite;
}

@keyframes drift {
  from { transform: translateY(0); }
  to { transform: translateY(-40px); }
}

#app {
  position: relative;
  max-width: 1040px;
  margin: 0 auto;
  padding: 1.25rem 1rem 2.5rem;
}

.topbar {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.75rem 1.5rem;
  margin-bottom: 1.25rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
}

.brand-mark {
  width: 1.35rem;
  height: 1.35rem;
  border-radius: 0.25rem;
  background:
    conic-gradient(from 210deg, var(--cyan), var(--amber), var(--rose), var(--cyan));
  box-shadow: 0 0 18px rgba(61, 231, 255, 0.45);
  animation: spin 8s linear infinite;
}

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

.brand h1 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  letter-spacing: 0.04em;
  text-transform: uppercase;
  background: linear-gradient(90deg, var(--cyan), #fff 45%, var(--amber));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.tagline {
  margin: 0;
  color: var(--muted);
  font-size: 0.95rem;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 1rem;
  padding: 1.25rem 1.35rem 1.5rem;
  backdrop-filter: blur(8px);
  animation: fadeUp 0.45s ease both;
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: none; }
}

.panel h2 {
  margin: 0 0 0.35rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--cyan);
}

.lede { margin: 0 0 1rem; color: var(--muted); }

.student-list {
  display: grid;
  gap: 0.65rem;
}

.student-card {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.35rem 1rem;
  align-items: center;
  width: 100%;
  text-align: left;
  padding: 0.85rem 1rem;
  border-radius: 0.75rem;
  border: 1px solid rgba(61, 231, 255, 0.18);
  background: rgba(5, 16, 26, 0.65);
  color: inherit;
  font: inherit;
  cursor: pointer;
  transition: border-color 0.15s, transform 0.15s, background 0.15s;
}

.student-card:hover,
.student-card:focus-visible {
  border-color: var(--cyan);
  background: rgba(61, 231, 255, 0.08);
  transform: translateX(3px);
  outline: none;
}

.student-card .name {
  font-weight: 600;
  font-size: 1.05rem;
}

.student-card .meta {
  color: var(--muted);
  font-size: 0.85rem;
}

.student-card .grade-pill {
  font-family: var(--font-display);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
  color: var(--amber);
  border: 1px solid rgba(255, 179, 71, 0.45);
  padding: 0.35rem 0.55rem;
  border-radius: 0.4rem;
}

.btn {
  font-family: var(--font-display);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  border-radius: 0.55rem;
  border: 1px solid transparent;
  padding: 0.75rem 1.2rem;
  cursor: pointer;
  transition: transform 0.12s, box-shadow 0.12s, background 0.12s;
}

.btn:active { transform: translateY(1px); }

.btn.primary {
  background: linear-gradient(135deg, var(--cyan), #1aa8c4);
  color: #031018;
  box-shadow: 0 0 22px rgba(61, 231, 255, 0.35);
}

.btn.ghost {
  background: transparent;
  border-color: var(--line);
  color: var(--ink);
}

.btn.fire-mobile {
  display: none;
  width: 100%;
  margin-top: 0.75rem;
  background: linear-gradient(135deg, var(--rose), #c43a55);
  color: #fff;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-top: 1.25rem;
}

.brief {
  color: var(--ink);
  line-height: 1.55;
}

.brief ul {
  margin: 0.5rem 0 0;
  padding-left: 1.1rem;
  color: var(--muted);
}

.brief .stat {
  display: inline-block;
  margin-right: 0.75rem;
  color: var(--mint);
  font-family: var(--font-display);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
}

.error {
  color: var(--rose);
  margin-top: 0.75rem;
}

#screen-game {
  animation: fadeUp 0.35s ease both;
}

.hud {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr)) 1.4fr;
  gap: 0.5rem;
  margin-bottom: 0.65rem;
}

.hud-block {
  background: rgba(5, 16, 26, 0.7);
  border: 1px solid var(--line);
  border-radius: 0.55rem;
  padding: 0.45rem 0.6rem;
}

.hud-block .label {
  display: block;
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--muted);
  font-family: var(--font-display);
}

.hud-block span:last-child {
  font-family: var(--font-display);
  font-size: 1rem;
  color: var(--cyan);
}

.question-banner {
  text-align: center;
  font-family: var(--font-display);
  font-size: clamp(1.1rem, 2.8vw, 1.55rem);
  letter-spacing: 0.04em;
  padding: 0.65rem 0.75rem;
  margin-bottom: 0.55rem;
  border-radius: 0.65rem;
  border: 1px solid rgba(255, 179, 71, 0.4);
  background: linear-gradient(90deg, rgba(255,179,71,0.12), rgba(61,231,255,0.08));
  color: var(--amber);
  min-height: 2.6rem;
}

#game {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 0.75rem;
  border: 1px solid var(--line);
  background: #02080f;
  touch-action: none;
  cursor: crosshair;
}

.controls-hint {
  margin: 0.55rem 0 0;
  color: var(--muted);
  font-size: 0.82rem;
}

.platform-ok { color: var(--mint); }
.platform-bad { color: var(--rose); }
.mono { font-family: ui-monospace, SFMono-Regular, Menlo, monospace; font-size: 0.85em; }

@media (max-width: 720px) {
  .hud {
    grid-template-columns: repeat(2, 1fr);
  }
  .hud-block.wide { grid-column: 1 / -1; }
  .btn.fire-mobile { display: block; }
}