/* ===================================================================
 * 浮点数文章（floating-point-01）的配图和交互组件
 *
 * 只在这篇文章里引入，所有选择器挂在 .fpv 下，不影响主题。
 * 占位写法：<div class="fpv" data-fig="bits"></div>，由 /js/float-viz.js 渲染。
 * =================================================================== */

/* 亮色（默认） */
.fpv {
  --fpv-text: var(--text-p1, rgba(0, 0, 0, 0.85));
  --fpv-p2: var(--text-p2, rgba(0, 0, 0, 0.68));
  --fpv-p3: var(--text-p3, rgba(0, 0, 0, 0.58));
  --fpv-block: var(--block, rgba(20, 50, 60, 0.04));
  --fpv-border: var(--block-border, rgba(20, 50, 60, 0.10));

  --fpv-line: rgba(0, 0, 0, 0.24);
  --fpv-inner: rgba(20, 50, 60, 0.04);
  --fpv-inner-border: rgba(20, 50, 60, 0.10);
  --fpv-cyan: var(--theme, #1ccffd);
  --fpv-cyan-a: rgba(28, 207, 253, 0.22);
  --fpv-cyan-text: #047a9a;
  --fpv-accent: #ff5f24;
  --fpv-accent-text: #c2410c;
  --fpv-ok: #2e7d32;
  --fpv-ok-a: rgba(46, 125, 50, 0.14);
  --fpv-bad: #d32f2f;
  --fpv-bad-a: rgba(211, 47, 47, 0.24);
  --fpv-sign: #7e57c2;
  --fpv-exp: #43a047;
  --fpv-man: #1e88e5;
}
.fpv[data-fig="round"],
.fpv[data-fig="widget"] {
  --fpv-ok-a: rgba(46, 125, 50, 0.12);
}
.fpv[data-fig="widget"] {
  --fpv-bad-a: rgba(211, 47, 47, 0.18);
}

/* 暗色 */
:root[data-theme="dark"] .fpv {
  --fpv-line: rgba(255, 255, 255, 0.24);
  --fpv-inner: rgba(255, 255, 255, 0.05);
  --fpv-inner-border: rgba(255, 255, 255, 0.10);
  --fpv-cyan-a: rgba(28, 207, 253, 0.20);
  --fpv-cyan-text: #5ddcfd;
  --fpv-accent: #ff6b3d;
  --fpv-accent-text: #ff8a65;
  --fpv-ok: #6fcf73;
  --fpv-ok-a: rgba(111, 207, 115, 0.16);
  --fpv-bad: #ff6b6b;
  --fpv-bad-a: rgba(255, 107, 107, 0.30);
  --fpv-sign: #b39ddb;
  --fpv-exp: #81c784;
  --fpv-man: #64b5f6;
}
:root[data-theme="dark"] .fpv[data-fig="round"] {
  --fpv-ok-a: rgba(111, 207, 115, 0.14);
}
:root[data-theme="dark"] .fpv[data-fig="widget"] {
  --fpv-bad-a: rgba(255, 107, 107, 0.26);
}

/* 跟随系统配色时的暗色 */
@media (prefers-color-scheme: dark) {
  :root:not([data-theme]) .fpv {
    --fpv-line: rgba(255, 255, 255, 0.24);
    --fpv-inner: rgba(255, 255, 255, 0.05);
    --fpv-inner-border: rgba(255, 255, 255, 0.10);
    --fpv-cyan-a: rgba(28, 207, 253, 0.20);
    --fpv-cyan-text: #5ddcfd;
    --fpv-accent: #ff6b3d;
    --fpv-accent-text: #ff8a65;
    --fpv-ok: #6fcf73;
    --fpv-ok-a: rgba(111, 207, 115, 0.16);
    --fpv-bad: #ff6b6b;
    --fpv-bad-a: rgba(255, 107, 107, 0.30);
    --fpv-sign: #b39ddb;
    --fpv-exp: #81c784;
    --fpv-man: #64b5f6;
  }
  :root:not([data-theme]) .fpv[data-fig="round"] {
    --fpv-ok-a: rgba(111, 207, 115, 0.14);
  }
  :root:not([data-theme]) .fpv[data-fig="widget"] {
    --fpv-bad-a: rgba(255, 107, 107, 0.26);
  }
}

/* ---------- 容器 ---------- */
.fpv {
  position: relative;
  display: block;
  margin: 1.5rem 0;
  border-radius: 12px;
  background: var(--fpv-block);
  color: var(--fpv-text);
  line-height: 1.4;
}
.fpv:empty {
  display: none;
}
.fpv-body {
  box-sizing: border-box;
  padding: 28px 24px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.fpv .mono,
.fpv input,
.fpv button {
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}
.fpv sup {
  font-size: 0.7em;
  line-height: 0;
}
.fpv-caption {
  font-size: 13px;
  color: var(--fpv-p3);
}

/* 数轴区域：里面全是绝对定位的小块 */
.fpv-axis {
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
}
.fpv-axis > * {
  position: absolute;
  box-sizing: border-box;
}
.fpv-axis .fpv-label {
  white-space: nowrap;
  font-size: 13px;
}
.fpv-axis .fpv-center {
  transform: translateX(-50%);
}

/* 图例 */
.fpv-legend {
  display: flex;
  flex-wrap: wrap;
  column-gap: 24px;
  row-gap: 8px;
  font-size: 13px;
  color: var(--fpv-p2);
}
.fpv.is-narrow .fpv-legend {
  flex-direction: column;
}
.fpv-legend-item {
  display: flex;
  align-items: center;
  gap: 8px;
}
.fpv-legend-item > span:first-child {
  flex-shrink: 0;
  box-sizing: border-box;
}

/* ---------- 图 1 位布局 ---------- */
.fpv-bits {
  display: flex;
  flex-direction: column;
  gap: 18px;
}
.fpv-bits-row {
  display: flex;
  align-items: flex-start;
  column-gap: 16px;
  row-gap: 6px;
}
.fpv.is-narrow .fpv-bits-row {
  flex-direction: column;
}
.fpv-bits-name {
  width: 76px;
  font-size: 15px;
  line-height: 28px;
}
.fpv.is-narrow .fpv-bits-name {
  line-height: 20px;
}
.fpv-bits-segs {
  display: flex;
  gap: 5px;
}
.fpv.is-narrow .fpv-bits-segs {
  gap: 3px;
}
.fpv-seg {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  font-size: 12px;
}
.fpv-cells {
  display: flex;
  gap: 1px;
}
.fpv-cells > span {
  width: 8px;
  height: 28px;
  border-radius: 1px;
}
.fpv.is-narrow .fpv-cells > span {
  width: 3px;
}

/* ---------- 交互组件 ---------- */
.fpv-row {
  display: flex;
  align-items: center;
  gap: 14px;
}
.fpv-presets {
  flex-wrap: wrap;
  gap: 10px;
}
.fpv .fpv-row > label,
.fpv-presets > span {
  flex-shrink: 0;
  width: 40px;
  font-size: 16px;
}
.fpv-presets > span {
  font-size: 14px;
  color: var(--fpv-p3);
}
.fpv input.fpv-input {
  width: 240px;
  min-width: 0;
  height: 44px;
  margin: 0;
  box-sizing: border-box;
  padding: 0 14px;
  font-size: 18px;
  line-height: normal;
  border-radius: 8px;
  border: 1px solid var(--fpv-line);
  background: var(--fpv-inner);
  color: var(--fpv-text);
  box-shadow: none;
}
.fpv.is-narrow input.fpv-input {
  flex: 1;
  width: auto;
}
.fpv input.fpv-input:focus {
  outline: 2px solid var(--fpv-cyan);
  outline-offset: 1px;
}
.fpv button.fpv-preset {
  height: 44px;
  min-height: 44px;
  margin: 0;
  padding: 0 12px;
  border-radius: 8px;
  font-size: 14px;
  line-height: normal;
  cursor: pointer;
  background: transparent;
  border: 1px solid var(--fpv-line);
  color: var(--fpv-p2);
  box-shadow: none;
}
.fpv button.fpv-preset.is-active {
  background: var(--fpv-cyan-a);
  border-color: var(--fpv-cyan);
  color: var(--fpv-text);
}
.fpv-err {
  font-size: 14px;
  color: var(--fpv-bad);
}
.fpv-result {
  display: flex;
  flex-direction: column;
  gap: 16px;
}
.fpv-result:empty {
  display: none;
}
.fpv-panel {
  padding: 16px;
  border-radius: 10px;
  background: var(--fpv-inner);
  border: 1px solid var(--fpv-inner-border);
}
.fpv-info {
  display: grid;
  grid-template-columns: 96px minmax(0, 1fr);
  row-gap: 10px;
  column-gap: 12px;
  align-items: baseline;
  font-size: 14px;
}
.fpv.is-narrow .fpv-info {
  grid-template-columns: 84px minmax(0, 1fr);
}
.fpv-muted {
  color: var(--fpv-p3);
}
.fpv-big {
  font-size: 17px;
  overflow-wrap: anywhere;
}
.fpv-ruler {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.fpv-ruler .fpv-legend {
  column-gap: 18px;
  row-gap: 6px;
  font-size: 12px;
  color: var(--fpv-p3);
}
.fpv-ruler .fpv-legend-item {
  gap: 6px;
}
.fpv.is-narrow .fpv-ruler .fpv-legend {
  flex-direction: row;
}
.fpv-cols {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}
.fpv.is-narrow .fpv-cols {
  grid-template-columns: minmax(0, 1fr);
}
.fpv-col {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.fpv-col-head {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 16px;
}
.fpv-col-head > span {
  width: 10px;
  height: 10px;
  border-radius: 50%;
}
.fpv-code {
  margin-top: -8px;
  font-size: 12px;
  color: var(--fpv-p3);
  overflow-wrap: anywhere;
}
.fpv-step {
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.fpv-step > div:first-child {
  font-size: 13px;
  color: var(--fpv-p3);
}
.fpv-step > div:last-child {
  font-size: 18px;
  overflow-wrap: anywhere;
}
.fpv-badge {
  align-self: flex-start;
  padding: 6px 12px;
  border-radius: 999px;
  font-size: 14px;
  background: var(--fpv-ok-a);
  color: var(--fpv-ok);
}
.fpv-badge.is-bad {
  background: var(--fpv-bad-a);
  color: var(--fpv-bad);
}