:root {
  --bg: #f4f1ea;
  --panel: #fffdf8;
  --ink: #1f2430;
  --muted: #5c6575;
  --line: #d7d0c4;
  --accent: #1f5f8b;
  --accent-dark: #164866;
  --tension: #c0392b;
  --compression: #1f4e79;
  --zero: #7b8494;
  --ok: #1e6b45;
  --err: #9b2c2c;
  --shadow: 0 8px 24px rgba(31, 36, 48, 0.08);
  font-family: "Segoe UI", "Apple SD Gothic Neo", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  color: var(--ink);
  background: radial-gradient(circle at top left, #fff 0, var(--bg) 42%);
}

.topbar {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: flex-end;
  padding: 20px 24px 12px;
}

h1,
h2 {
  margin: 0;
}

h1 {
  font-size: 1.6rem;
}

h2 {
  font-size: 1rem;
}

.subtitle,
.hint {
  margin: 6px 0 0;
  color: var(--muted);
  font-size: 0.92rem;
}

.actions,
.card-head,
.legend {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
}

.card-head {
  justify-content: space-between;
  margin-bottom: 10px;
}

.layout {
  display: grid;
  grid-template-columns: minmax(320px, 420px) 1fr;
  gap: 16px;
  padding: 0 24px 32px;
}

.panel,
.preview {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px;
  box-shadow: var(--shadow);
}

.canvas-card canvas {
  width: 100%;
  height: auto;
  display: block;
  background: #fbfaf6;
  border: 1px solid var(--line);
  border-radius: 10px;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
}

th,
td {
  padding: 6px 4px;
  text-align: left;
  border-bottom: 1px solid #eee7db;
}

th {
  color: var(--muted);
  font-weight: 600;
}

input,
select,
button {
  font: inherit;
}

input,
select {
  width: 100%;
  min-width: 0;
  padding: 6px 8px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
}

button {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 999px;
  padding: 7px 12px;
  cursor: pointer;
}

button:hover {
  border-color: var(--accent);
}

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

button.primary:hover {
  background: var(--accent-dark);
}

button.ghost {
  padding: 4px 8px;
  color: var(--muted);
}

.swatch {
  width: 12px;
  height: 12px;
  border-radius: 999px;
  display: inline-block;
}

.swatch.tension {
  background: var(--tension);
}

.swatch.compression {
  background: var(--compression);
}

.swatch.zero {
  background: var(--zero);
}

.status {
  min-height: 1.4em;
  margin: 0;
  font-weight: 600;
}

.status.ok {
  color: var(--ok);
}

.status.err {
  color: var(--err);
}

.kind-tension {
  color: var(--tension);
  font-weight: 700;
}

.kind-compression {
  color: var(--compression);
  font-weight: 700;
}

.kind-zero {
  color: var(--zero);
}

@media (max-width: 980px) {
  .topbar,
  .layout {
    display: flex;
    flex-direction: column;
  }

  .topbar {
    align-items: stretch;
  }
}