/* 英寸分数计算器 — 仅本页样式
 * 与站内其它工具保持同构：沿用 .calculator-container / .calc-card /
 * .input-field / .fraction-group 等既有命名与 CSS 变量，不覆盖站级样式。
 */

.calculator-container {
  max-width: 900px;
  margin: 1rem auto;
  padding: 0 1rem;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

.page-header { margin-bottom: 1rem; }
.page-title { margin: 0; font-size: 1.6rem; color: var(--text-primary, #1a1a1a); }
.page-sub {
  margin: .35rem 0 0;
  font-size: .9rem;
  color: var(--text-secondary, #666);
  line-height: 1.5;
}

.calc-card {
  background: var(--bg-card, #fff);
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 10px;
  padding: 1rem;
  margin-bottom: 1rem;
}

.section-title {
  margin: 0 0 .75rem;
  font-size: 1.15rem;
  color: var(--text-primary, #1a1a1a);
  padding-bottom: .35rem;
  border-bottom: 1px solid var(--border-color, #e2e8f0);
}

/* ---- 操作数行 ---- */
.frac-row {
  display: flex;
  gap: .4rem;
  align-items: flex-start;
  margin-bottom: .5rem;
}
.frac-row.tight { margin-bottom: 0; }

.operand-tag {
  flex: 0 0 1.4rem;
  font-weight: 700;
  color: var(--text-secondary, #888);
  line-height: 34px;
  font-size: .95rem;
}

.input-wrapper { flex: 1; display: flex; flex-direction: column; }

.input-field {
  width: 100%;
  padding: .4rem;
  border: 1px solid var(--border-color, #ccc);
  border-radius: 5px;
  font-size: 1rem;
  height: 34px;
  box-sizing: border-box;
  background: var(--bg-input, #fff);
  color: var(--text-primary, #1a1a1a);
}
.input-suffix {
  font-size: .7rem;
  color: var(--text-secondary, #888);
  margin-top: .1rem;
  text-align: right;
  margin-right: 2px;
}
.input-label {
  display: block;
  font-size: .8rem;
  color: var(--text-secondary, #666);
  margin-bottom: .25rem;
}

.fraction-group {
  display: flex;
  align-items: center;
  border: 1px solid var(--border-color, #ccc);
  border-radius: 5px;
  background: #fff;
  height: 34px;
  flex: 0 0 5.2rem;
  overflow: hidden;
}
.frac-input-native {
  width: 100%;
  border: none;
  padding: 0 0 0 .3rem;
  font-size: 1rem;
  height: 100%;
  outline: none;
  -moz-appearance: textfield;
  background: transparent;
}
.frac-suffix {
  font-size: .75rem;
  color: #888;
  background: #f8fafc;
  height: 100%;
  display: flex;
  align-items: center;
  padding: 0 .35rem;
  border-left: 1px solid var(--border-color, #eee);
}

/* ---- 运算符 ---- */
.op-row { display: flex; gap: .4rem; margin: .25rem 0 .5rem 1.8rem; }
.op-btn {
  flex: 1;
  height: 38px;
  font-size: 1.15rem;
  border: 1px solid var(--border-color, #ccc);
  border-radius: 6px;
  background: #fff;
  color: var(--text-primary, #333);
  cursor: pointer;
  transition: background .12s, border-color .12s;
}
.op-btn:hover { background: #f1f5f9; }
.op-btn.active {
  background: #2563eb;
  border-color: #2563eb;
  color: #fff;
  font-weight: 700;
}

.hint {
  margin: .1rem 0 .6rem 1.8rem;
  font-size: .75rem;
  color: var(--text-secondary, #94a3b8);
}

/* ---- 结果 ---- */
.result-box {
  background: #f8fafc;
  border: 1px solid var(--border-color, #e2e8f0);
  border-radius: 8px;
  padding: .85rem 1rem;
  text-align: center;
  margin-top: .25rem;
}
.result-main {
  font-size: 2rem;
  font-weight: 700;
  color: #1a1a1a;
  line-height: 1.2;
  font-variant-numeric: tabular-nums;
}
/* 近似值必须看得出来，不与精确值同形 */
.result-main.is-approx { color: #b45309; }

.result-sub {
  margin-top: .3rem;
  font-size: .85rem;
  color: var(--text-secondary, #64748b);
}
.result-sub .dot { margin: 0 .4rem; color: #cbd5e1; }
.result-exact {
  margin-top: .3rem;
  font-size: .78rem;
  color: #b45309;
}

/* ---- 动作按钮 ---- */
.action-row { display: flex; gap: .5rem; margin-top: .75rem; flex-wrap: wrap; }
.wt-btn {
  flex: 1;
  min-width: 8rem;
  height: 38px;
  border-radius: 6px;
  border: 1px solid #2563eb;
  background: #2563eb;
  color: #fff;
  font-size: .9rem;
  cursor: pointer;
}
.wt-btn.ghost { background: #fff; color: #2563eb; }
.wt-btn:hover { opacity: .9; }

/* ---- 换算区 ---- */
.conv-grid {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: .75rem;
  align-items: end;
}
.conv-arrows {
  font-size: 1.3rem;
  color: var(--text-secondary, #94a3b8);
  padding-bottom: .5rem;
}

.foot-note {
  font-size: .75rem;
  color: var(--text-secondary, #94a3b8);
  line-height: 1.6;
  margin: 0 0 2rem;
}

/* ---- 手机优先：他在工地上用的就是这个断点 ---- */
@media (max-width: 640px) {
  .calculator-container { padding: 0 .75rem; }
  .page-title { font-size: 1.3rem; }
  .result-main { font-size: 1.75rem; }
  .op-row, .hint { margin-left: 0; }
  .conv-grid { grid-template-columns: 1fr; }
  .conv-arrows { text-align: center; padding: 0; }
  .input-field, .frac-input-native { font-size: 16px; } /* iOS 聚焦时不缩放 */
  .wt-btn { min-width: 6rem; }
}