:root {
  color-scheme: light;
  --bg: #eef3f8;
  --ink: #172033;
  --muted: #617084;
  --surface: #ffffff;
  --panel: #f8fafc;
  --line: rgba(23, 32, 51, 0.12);
  --accent: #1f8a70;
  --shadow: 0 24px 70px rgba(33, 46, 70, 0.14);
  --mark-width: 72px;
  --mark-height: 120px;
  --mark-thickness: 24px;
  --mark-color: #1f8a70;
  --mark-rotation: 0deg;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  font-family: "Avenir Next", "Hiragino Sans", sans-serif;
  color: var(--ink);
  background:
    linear-gradient(rgba(23, 32, 51, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(23, 32, 51, 0.04) 1px, transparent 1px),
    var(--bg);
  background-size: 36px 36px;
}

.layout {
  width: min(1040px, calc(100vw - 40px));
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 24px;
  align-items: stretch;
}

.stage,
.side {
  border: 1px solid var(--line);
  border-radius: 24px;
  background: rgba(255, 255, 255, 0.84);
  box-shadow: var(--shadow);
}

.stage {
  display: grid;
  place-items: center;
  min-height: 560px;
  padding: 40px;
}

.preview {
  display: grid;
  place-items: center;
  width: min(100%, 420px);
  aspect-ratio: 1;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: var(--surface);
}

.chevron {
  width: var(--mark-width);
  height: var(--mark-height);
  background: var(--mark-color);
  transform: rotate(var(--mark-rotation));
  transition: 160ms ease;
  clip-path: polygon(
    0 0,
    var(--mark-thickness) 0,
    100% 50%,
    var(--mark-thickness) 100%,
    0 100%,
    calc(100% - var(--mark-thickness)) 50%
  );
}

.side {
  padding: 24px;
  background: var(--panel);
}

.side h1 {
  margin: 0 0 10px;
  font-size: 24px;
  line-height: 1.15;
}

.side p {
  margin: 0 0 20px;
  color: var(--muted);
  line-height: 1.7;
}

.controls {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-bottom: 18px;
}

button {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 10px 14px;
  background: #fff;
  color: var(--muted);
  font: inherit;
  cursor: pointer;
  transition: 160ms ease;
}

button.active {
  border-color: transparent;
  background: var(--accent);
  color: #fff;
}

.fields {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-bottom: 18px;
}

label {
  display: grid;
  gap: 6px;
  color: var(--muted);
  font-size: 13px;
}

input {
  width: 100%;
  min-width: 0;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff;
  color: var(--ink);
  font: inherit;
  padding: 10px 12px;
}

input[type="color"] {
  height: 42px;
  padding: 4px;
}

.code {
  padding: 16px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background: #101827;
  color: #dce8f7;
  font-size: 14px;
  line-height: 1.7;
  white-space: pre-wrap;
}

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

  .stage {
    min-height: 420px;
  }
}