:root {
  --bg: #0f1115;
  --panel: #171a21;
  --panel-2: #1e222b;
  --fg: #e6e8ec;
  --muted: #8a93a6;
  --accent: #9ae6b4;
  --accent-2: #f5c26b;
  --border: #272b35;
  --error: #ff6b6b;
  --diff: #f5c26b;
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans",
    "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  font-size: 15px;
  line-height: 1.6;
}

header {
  padding: 24px 32px 8px;
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid var(--border);
}
header h1 { margin: 0; font-size: 22px; }
header #subtitle {
  grid-column: 1 / 2;
  margin: 4px 0 0;
  color: var(--muted);
  font-size: 14px;
}
.lang-switch {
  grid-column: 2 / 3;
  grid-row: 1 / 3;
  display: flex;
  align-items: center;
  gap: 6px;
}

main {
  padding: 24px 32px 48px;
  max-width: 800px;
  margin: 0 auto;
}

section { margin-bottom: 24px; }

.input-section {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px 24px;
}

.row {
  display: flex;
  gap: 14px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.field {
  flex: 1;
  min-width: 160px;
}

label {
  display: block;
  font-size: 12px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
  margin-bottom: 4px;
}

input[type="number"], input[type="text"], select {
  width: 100%;
  padding: 10px 12px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--fg);
  font-family: "SF Mono", Menlo, Consolas, monospace;
  font-size: 16px;
}
input:focus, select:focus { outline: none; border-color: var(--accent); }

.ratio-inputs {
  display: flex;
  gap: 6px;
  align-items: center;
}
.ratio-inputs input { text-align: center; }
.ratio-inputs span {
  color: var(--muted);
  font-family: "SF Mono", Menlo, Consolas, monospace;
}

.mode-tabs {
  display: flex;
  gap: 8px;
  align-items: center;
  margin: 14px 0;
  flex-wrap: wrap;
}
.mode-tabs > span {
  font-size: 11px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-right: 6px;
}
.mode-tabs button {
  padding: 6px 14px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--muted);
  font-size: 13px;
  cursor: pointer;
  font-family: inherit;
}
.mode-tabs button.active {
  background: var(--accent);
  color: #0b1320;
  border-color: var(--accent);
  font-weight: 700;
}

.mode-fields { margin-bottom: 12px; }

.error {
  margin-top: 10px;
  color: var(--error);
  font-size: 13px;
  font-family: "SF Mono", Menlo, Consolas, monospace;
}

.result {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 24px 28px;
}

.hero {
  text-align: center;
  padding: 18px 0 10px;
}
.hero-label {
  font-size: 12px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.hero-value {
  font-size: 54px;
  color: var(--accent);
  font-weight: 700;
  font-family: "SF Mono", Menlo, Consolas, monospace;
  margin-top: 4px;
}

.shares-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 10px;
  margin-bottom: 10px;
}
.share-cell {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px;
  text-align: center;
}
.share-index {
  font-size: 10px;
  color: var(--muted);
  text-transform: uppercase;
}
.share-amount {
  font-size: 20px;
  font-weight: 600;
  color: var(--accent);
  font-family: "SF Mono", Menlo, Consolas, monospace;
  margin: 2px 0;
}
.share-weight {
  font-size: 11px;
  color: var(--muted);
  font-family: "SF Mono", Menlo, Consolas, monospace;
}

.meta {
  display: flex;
  justify-content: space-between;
  margin-top: 14px;
  padding-top: 14px;
  border-top: 1px dashed var(--border);
  color: var(--muted);
  font-size: 13px;
  font-family: "SF Mono", Menlo, Consolas, monospace;
}
.meta .diff strong { color: var(--diff); }
.meta strong { color: var(--fg); }

footer {
  padding: 24px 32px;
  border-top: 1px solid var(--border);
  color: var(--muted);
  font-size: 12px;
  text-align: center;
}