* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: Arial, sans-serif;
  background:
    radial-gradient(circle at top left, rgba(239, 68, 68, 0.22), transparent 28%),
    radial-gradient(circle at top right, rgba(59, 130, 246, 0.25), transparent 30%),
    #020617;
  color: #f8fafc;
}

.page {
  max-width: 1180px;
  margin: auto;
  padding: 36px 22px;
}

.hero {
  text-align: center;
  margin-bottom: 28px;
}

.hero h1 {
  font-size: clamp(2.3rem, 6vw, 4.3rem);
  margin: 0 0 12px;
}

.hero p {
  max-width: 800px;
  margin: auto;
  color: #cbd5e1;
  font-size: 1.1rem;
}

.dashboard {
  display: grid;
  grid-template-columns: 340px 1fr;
  gap: 22px;
}

.controls,
.visual,
.explanation {
  background: rgba(15, 23, 42, 0.88);
  border: 1px solid rgba(148, 163, 184, 0.22);
  border-radius: 24px;
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.35);
}

.controls {
  padding: 24px;
}

.controls h2 {
  margin-top: 0;
}

label {
  display: block;
  margin: 18px 0 10px;
}

input[type="range"] {
  width: 100%;
  accent-color: #facc15;
}

.buttons {
  display: grid;
  gap: 10px;
  margin: 22px 0;
}

button {
  padding: 12px;
  border: 1px solid rgba(148, 163, 184, 0.25);
  background: #020617;
  color: #e2e8f0;
  border-radius: 14px;
  cursor: pointer;
}

button:hover {
  background: #111827;
}

.stats {
  display: grid;
  gap: 12px;
}

.stats div {
  background: rgba(2, 6, 23, 0.72);
  border: 1px solid rgba(148, 163, 184, 0.16);
  border-radius: 16px;
  padding: 14px;
}

.stats span {
  display: block;
  color: #94a3b8;
  font-size: 0.86rem;
  margin-bottom: 6px;
}

.visual {
  padding: 18px;
}

canvas {
  display: block;
  width: 100%;
  height: auto;
  background: #020617;
  border-radius: 18px;
}

.explanation {
  margin-top: 22px;
  padding: 26px;
}

.equation {
  text-align: center;
  color: #facc15;
  font-size: 1.8rem;
  font-weight: bold;
}

@media (max-width: 850px) {
  .dashboard {
    grid-template-columns: 1fr;
  }
}