:root {
  --bg-top: #fff2d5;
  --bg-bottom: #d7f0ff;
  --panel: rgba(255, 255, 255, 0.8);
  --ink: #1b1b1f;
  --accent: #0f766e;
  --accent-strong: #115e59;
  --border: rgba(27, 27, 31, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Avenir Next", "Trebuchet MS", sans-serif;
  color: var(--ink);
  background:
    radial-gradient(circle at 20% 15%, rgba(255, 255, 255, 0.65), transparent 42%),
    radial-gradient(circle at 80% 80%, rgba(255, 220, 150, 0.45), transparent 38%),
    linear-gradient(145deg, var(--bg-top), var(--bg-bottom));
  display: grid;
  place-items: center;
  padding: 1rem;
}

.app {
  width: min(38rem, 100%);
  background: var(--panel);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border);
  border-radius: 1rem;
  padding: clamp(1rem, 3vw, 2rem);
  box-shadow: 0 0.8rem 2.2rem rgba(0, 0, 0, 0.12);
  animation: rise 450ms ease-out;
}

h1 {
  margin: 0 0 0.4rem;
  font-size: clamp(1.5rem, 2.4vw, 2.2rem);
}

.subtitle {
  margin: 0 0 1.25rem;
  line-height: 1.5;
}

.controls {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 1.25rem;
}

.controlGroup {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.controlGroupRange input[type="range"] {
  width: 100%;
}

.controlRow {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  align-items: stretch;
}

.toggleGroup {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

label {
  font-weight: 600;
}

.checkboxControl {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  font-weight: 600;
}

.checkboxControl input[type="checkbox"] {
  width: 1rem;
  height: 1rem;
  margin: 0;
  accent-color: var(--accent);
}

input[type="range"] {
  accent-color: var(--accent);
  cursor: pointer;
}

select,
button {
  width: 100%;
  border-radius: 0.6rem;
  border: 1px solid var(--border);
  padding: 0.7rem 0.8rem;
  font-size: 1rem;
  font: inherit;
}

#scaleSelect {
  transition: box-shadow 220ms ease, border-color 220ms ease;
}

#scaleSelect.scaleChanged {
  border-color: var(--accent);
  box-shadow: 0 0 0 0.2rem color-mix(in srgb, var(--accent) 30%, transparent);
}

button {
  background: var(--accent);
  border-color: transparent;
  color: #fff;
  cursor: pointer;
  transition: transform 120ms ease, background 120ms ease;
}

button:hover {
  background: var(--accent-strong);
}

button:active {
  transform: translateY(1px);
}

.status h2 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.status ul {
  margin: 0;
  padding-left: 1.1rem;
  line-height: 1.7;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(8px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (min-width: 640px) {
  .controlRow {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
  }

  .toggleGroup {
    flex: 1;
  }

  button {
    width: 8rem;
    flex-shrink: 0;
  }
}