:root {
  --bg: #c9d1d9;
  --panel: #ece9d8;
  --surface: #f7f4e8;
  --ink: #111;
  --muted: #4b4b4b;
  --border-dark: #808080;
  --border-light: #ffffff;
  --accent: #000080;
  --blue: #0056d6;
  --green: #0a7d35;
  --red: #b00020;
  --yellow: #f6d876;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  font-family: "MS Sans Serif", Tahoma, Geneva, Verdana, sans-serif;
  font-size: 12px;
  color: var(--ink);
  background:
    linear-gradient(180deg, #d8dee6 0%, #cfd6df 100%);
}

body {
  min-height: 100vh;
}

a {
  color: var(--blue);
}

.shell {
  max-width: 1380px;
  margin: 0 auto;
  padding: 12px;
}

.title-bar,
.panel,
.hero,
.status-bar,
.nav-strip {
  background: var(--panel);
  border-top: 2px solid var(--border-light);
  border-left: 2px solid var(--border-light);
  border-right: 2px solid var(--border-dark);
  border-bottom: 2px solid var(--border-dark);
}

.title-bar {
  padding: 10px 14px;
  margin-bottom: 10px;
}

.title-bar h1,
.hero h1 {
  margin: 0;
  color: var(--accent);
  font-size: 20px;
}

.subtitle {
  margin-top: 4px;
  color: var(--muted);
}

.nav-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  padding: 8px;
  margin-bottom: 10px;
}

.nav-button,
.button,
.link-button {
  appearance: none;
  background: linear-gradient(180deg, #fefcf3 0%, #ddd7c7 100%);
  border-top: 1px solid var(--border-light);
  border-left: 1px solid var(--border-light);
  border-right: 1px solid var(--border-dark);
  border-bottom: 1px solid var(--border-dark);
  color: var(--ink);
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  font: inherit;
  min-height: 28px;
  min-width: 90px;
  padding: 4px 10px;
  text-decoration: none;
}

.nav-button.active {
  background: linear-gradient(180deg, #123d9f 0%, #0a2e83 100%);
  color: #fff;
}

.page-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 14px;
}

.hero {
  padding: 18px;
  margin-bottom: 14px;
}

.hero p {
  max-width: 840px;
  line-height: 1.55;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border-dark);
  padding: 14px;
}

.card h2,
.card h3,
.frame-title {
  margin: 0 0 10px;
  color: var(--accent);
}

.card p,
.note,
.help,
.status-copy {
  line-height: 1.55;
}

.list {
  margin: 0;
  padding-left: 18px;
  line-height: 1.55;
}

.layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 12px;
}

.sidebar {
  position: sticky;
  top: 12px;
  align-self: start;
}

.sim-panel {
  display: none;
  padding: 12px;
  margin-bottom: 10px;
}

.sim-panel.active {
  display: block;
}

.frame {
  background: var(--surface);
  border: 1px solid var(--border-dark);
  padding: 10px;
  margin-bottom: 10px;
}

.grid-2,
.grid-3,
.grid-4 {
  display: grid;
  gap: 10px;
}

.grid-2 {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.control-row {
  display: grid;
  grid-template-columns: 150px 1fr;
  gap: 8px;
  align-items: center;
  margin-bottom: 6px;
}

.control-row.compact {
  grid-template-columns: 110px 1fr;
}

.control-row label {
  color: var(--muted);
}

.textbox,
select,
input[type="text"],
input[type="number"] {
  width: 100%;
  min-height: 26px;
  padding: 4px 6px;
  font: inherit;
  border-top: 1px solid var(--border-dark);
  border-left: 1px solid var(--border-dark);
  border-right: 1px solid var(--border-light);
  border-bottom: 1px solid var(--border-light);
  background: #fff;
}

.readonly {
  background: #ececec;
}

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

.range-wrap {
  display: flex;
  align-items: center;
  gap: 8px;
}

.range-value {
  min-width: 52px;
  text-align: right;
  color: var(--muted);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}

.canvas-stack {
  display: grid;
  gap: 10px;
}

.canvas-frame {
  background: #fff;
  border: 1px solid var(--border-dark);
  padding: 8px;
}

canvas {
  display: block;
  width: 100%;
  background: #fff;
}

.mini-canvas {
  height: 180px;
}

.sim-canvas {
  height: 260px;
}

.wide-canvas {
  height: 180px;
}

.harmonics {
  display: grid;
  grid-template-columns: repeat(13, minmax(28px, 1fr));
  gap: 6px;
  align-items: end;
}

.harmonic {
  display: grid;
  gap: 6px;
  justify-items: center;
}

.harmonic input[type="range"] {
  writing-mode: bt-lr;
  -webkit-appearance: slider-vertical;
  width: 22px;
  height: 130px;
}

.harmonic-label {
  font-size: 11px;
}

.status-bar {
  margin-top: 10px;
  padding: 7px 10px;
  display: flex;
  justify-content: space-between;
  gap: 12px;
}

.status-copy strong {
  color: var(--accent);
}

.pill {
  background: #f7f0b0;
  border: 1px solid #b18f00;
  padding: 2px 6px;
}

.mono {
  font-family: "Courier New", monospace;
}

.notice {
  background: #fff9cf;
  border: 1px solid #ceb000;
  padding: 10px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

@media (max-width: 980px) {
  .layout,
  .grid-2,
  .grid-3,
  .grid-4 {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
  }

  .control-row,
  .control-row.compact {
    grid-template-columns: 1fr;
  }

  .harmonics {
    overflow-x: auto;
    padding-bottom: 6px;
  }
}