:root {
  --max: 960px;
  --bg: #f7f9fc;
  --panel: #ffffff;
  --panel-soft: #fafcff;
  --border: #dfe5ee;
  --text: #222;
  --muted: #666;
  --accent: #eef6ff;
  --accent-border: #bcd7ff;
  --accent-strong: #4f8cff;
  --shadow: 0 12px 30px rgba(0, 0, 0, 0.08);
}

* { box-sizing: border-box; }

body {
  font-family: system-ui, -apple-system, Segoe UI, Roboto, "Hiragino Kaku Gothic ProN", "Meiryo", sans-serif;
  margin: 0;
  padding: 24px;
  background: var(--bg);
  color: var(--text);
}

.wrap {
  max-width: var(--max);
  margin: 0 auto;
}

.container {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 28px;
  box-shadow: var(--shadow);
}

h1 {
  font-size: 24px;
  margin: 0 0 12px;
  text-align: center;
}

.lead {
  text-align: center;
  color: var(--muted);
  font-size: 14px;
  margin: 0 0 18px;
}

.controls {
  display: grid;
  grid-template-columns: repeat(2, minmax(280px, 1fr));
  gap: 12px;
  margin-bottom: 20px;
}

fieldset {
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  margin: 0;
  background: var(--panel-soft);
}

legend {
  padding: 0 6px;
  font-weight: 600;
}

.control-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 10px;
  font-size: 14px;
  color: #333;
}

.control-row:last-child {
  margin-bottom: 0;
}

.control-buttons {
  display: flex;
  gap: 8px;
  flex: 0 0 auto;
}

button {
  border: 1px solid #ddd;
  border-radius: 10px;
  background: #fafafa;
  color: var(--text);
  cursor: pointer;
  transition: transform .1s, background .2s, border-color .2s;
}

button:hover {
  background: #fff;
  border-color: #cfd8e6;
}

button:active {
  transform: scale(.98);
}

button:focus-visible {
  outline: 3px solid #66ccff;
  outline-offset: 2px;
}

button:disabled {
  opacity: .45;
  cursor: not-allowed;
}

.small-button {
  min-width: 44px;
  padding: 10px 14px;
  font-size: 18px;
  line-height: 1;
}

.section-title {
  font-size: 14px;
  font-weight: 600;
  color: #444;
  margin: 18px 0 10px;
  text-align: center;
}

.boxes-wrapper {
  overflow-x: auto;
  padding: 6px 2px 8px;
  margin-bottom: 14px;
}

.boxes {
  display: flex;
  gap: 12px;
  justify-content: center;
  align-items: flex-end;
  min-width: fit-content;
}

.bit-wrapper {
  text-align: center;
  cursor: pointer;
  user-select: none;
  flex: 0 0 auto;
}

.bit-box {
  width: 68px;
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: #fff;
  font-size: 28px;
  font-weight: 700;
  transition: transform .1s, background .2s, border-color .2s, color .2s;
}

.bit-wrapper:hover .bit-box {
  transform: translateY(-1px);
  background: #fcfdff;
}

.bit-box.active {
  background: var(--accent);
  border-color: var(--accent-border);
  color: #1862d6;
}

.bit-label {
  margin-top: 8px;
  font-size: 13px;
  color: var(--muted);
  white-space: nowrap;
  font-variant-numeric: tabular-nums;
}

.dot-group {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: flex-end;
  height: 96px;
  flex: 0 0 auto;
  padding: 0 2px;
}

.dot {
  font-size: 30px;
  font-weight: 700;
  line-height: 1;
  margin-bottom: 22px;
  color: #444;
}

.results {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 8px;
}

.card {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  background: #fff;
}

.rank {
  font-weight: 600;
  color: #333;
  flex: 0 0 auto;
  white-space: nowrap;
}

.sumline {
  font-variant-numeric: tabular-nums;
  text-align: right;
  font-size: 24px;
  font-weight: 700;
  word-break: break-word;
  flex: 1 1 auto;
}

.muted {
  color: var(--muted);
  font-size: 13px;
}

.actions {
  margin-top: 16px;
  text-align: center;
}

.reset-button {
  padding: 10px 16px;
  font-size: 14px;
}

.footer {
  font-size: 12px;
  color: var(--muted);
  margin-top: 16px;
  text-align: center;
}

@media (max-width: 800px) {
  .controls {
    grid-template-columns: 1fr;
  }

  .container {
    padding: 22px;
  }

  .bit-box {
    width: 62px;
    height: 62px;
    font-size: 26px;
  }

  .sumline {
    font-size: 20px;
  }
}

input.sumline {
  border: none;
  background: transparent;
  font: inherit;
  color: inherit;
  width: 100%;
  text-align: right;
  padding: 0;
  outline: none;
  min-width: 0;
}

input.sumline:focus {
  color: var(--accent-strong);
}

@media (max-width: 520px) {
  body {
    padding: 14px;
  }

  h1 {
    font-size: 20px;
  }

  .card {
    flex-direction: column;
    align-items: flex-start;
  }

  .sumline {
    width: 100%;
    text-align: left;
  }
}