.dctool-app {
  --dctool-accent: #1a5fb4;
  --dctool-accent-dark: #103d78;
  --dctool-danger: #c01c28;
  --dctool-bg: #f5f7fa;
  --dctool-panel-bg: #ffffff;
  --dctool-border: #d8dde3;
  --dctool-text: #202020;
  --dctool-text-dim: #666666;

  max-width: 780px;
  margin: 0 auto;
  padding: 20px 16px 48px;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Meiryo", sans-serif;
  background: var(--dctool-bg);
  color: var(--dctool-text);
  box-sizing: border-box;
}

.dctool-app * { box-sizing: border-box; }

.dctool-app h1 {
  font-size: 20px;
  margin: 0 0 8px;
}

.dctool-lead {
  font-size: 13px;
  color: var(--dctool-text-dim);
  line-height: 1.6;
  margin: 0 0 16px;
}

.dctool-bar {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 12px;
  background: var(--dctool-panel-bg);
  border: 1px solid var(--dctool-border);
  border-radius: 8px;
  padding: 10px 12px;
  margin-bottom: 10px;
  font-size: 13px;
}

.dctool-bar label {
  display: flex;
  align-items: center;
  gap: 6px;
}

.dctool-bar select, .dctool-bar input[type="text"] {
  font-size: 13px;
  padding: 4px 6px;
  border: 1px solid var(--dctool-border);
  border-radius: 4px;
  background: #fff;
}

.dctool-bar input[type="text"] {
  min-width: 220px;
}

.dctool-tool-bar select {
  min-width: 320px;
  font-weight: bold;
}

.dctool-formula {
  font-size: 13px;
  color: #444;
  background: #eef3fb;
  border-radius: 6px;
  padding: 8px 10px;
  margin: 4px 0;
}

.dctool-note {
  font-size: 11.5px;
  color: var(--dctool-text-dim);
  line-height: 1.6;
  margin: 4px 0 14px;
}

.dctool-input-panel {
  background: var(--dctool-panel-bg);
  border: 1px solid var(--dctool-border);
  border-radius: 8px;
  padding: 14px 16px;
  margin-bottom: 14px;
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

.dctool-field-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: 13px;
}

.dctool-field-row label.dctool-field-label {
  flex: 0 0 auto;
  min-width: 220px;
  color: #333;
}

.dctool-field-row input[type="number"] {
  width: 140px;
  padding: 5px 7px;
  border: 1px solid var(--dctool-border);
  border-radius: 4px;
  font-size: 13px;
}

.dctool-field-row select {
  padding: 5px 7px;
  border: 1px solid var(--dctool-border);
  border-radius: 4px;
  font-size: 13px;
  flex: 1 1 auto;
  min-width: 180px;
}

.dctool-field-row .dctool-unit {
  color: var(--dctool-text-dim);
  font-size: 12px;
  min-width: 70px;
}

.dctool-field-row.dctool-hidden { display: none; }

.dctool-field-group-header {
  font-size: 12px;
  font-weight: bold;
  color: var(--dctool-accent-dark);
  margin: 6px 0 -2px;
  padding-top: 8px;
  border-top: 1px dashed var(--dctool-border);
}

.dctool-field-group-header:first-child {
  margin-top: 0;
  padding-top: 0;
  border-top: none;
}

.dctool-result-panel {
  background: var(--dctool-panel-bg);
  border: 1px solid var(--dctool-border);
  border-radius: 8px;
  padding: 14px 16px;
  margin-bottom: 14px;
}

.dctool-result-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-size: 13px;
  color: var(--dctool-text-dim);
  margin-bottom: 6px;
}

.dctool-timing {
  font-size: 11px;
  color: #8a8a8a;
}

.dctool-result-value {
  font-size: 20px;
  font-weight: bold;
  color: var(--dctool-accent-dark);
  margin-bottom: 6px;
  line-height: 1.4;
}

.dctool-result-value.dctool-error {
  color: var(--dctool-danger);
  font-size: 15px;
}

.dctool-result-sub {
  font-size: 12.5px;
  color: #444;
  line-height: 1.7;
  white-space: pre-line;
}

.dctool-chart-wrap {
  background: var(--dctool-panel-bg);
  border: 1px solid var(--dctool-border);
  border-radius: 8px;
  padding: 10px 14px 16px;
}

.dctool-diagram {
  width: 100%;
}

.dctool-diagram svg {
  width: 100%;
  height: auto;
  display: block;
}

.dctool-footnote {
  font-size: 11px;
  color: #999;
  line-height: 1.7;
  margin-top: 18px;
}