/* ============================================================
   辅食 / 奶量与热量需求计算器 —— 全新风格（柔和亲子主题）
   作用域 .bn，避免与全站其它工具样式冲突
   支持暗黑模式：跟随 <html data-theme="dark">
   ============================================================ */

.bn {
  --bn-bg: #fff8f3;
  --bn-bg-2: #ffe9ee;
  --bn-card: #ffffff;
  --bn-card-2: #fff2f0;
  --bn-text: #3b2f38;
  --bn-muted: #917f88;
  --bn-accent: #ff7a8a;
  --bn-accent-2: #ffb27a;
  --bn-accent-3: #1fae9c;
  --bn-border: #ffe0e7;
  --bn-shadow: 0 12px 30px rgba(255, 120, 140, .16);
  --bn-shadow-sm: 0 4px 14px rgba(255, 120, 140, .12);
  --bn-input-bg: #fff;
  --bn-track: #ffe3ea;

  position: relative;
  min-height: 60vh;
  padding: 28px 0 60px;
  color: var(--bn-text);
  background:
    radial-gradient(1200px 480px at 12% -8%, var(--bn-bg-2), transparent 60%),
    radial-gradient(900px 420px at 100% 0%, #fff1e3, transparent 55%),
    var(--bn-bg);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

[data-theme="dark"] .bn {
  --bn-bg: #15111e;
  --bn-bg-2: #241a32;
  --bn-card: #231b30;
  --bn-card-2: #2c2138;
  --bn-text: #efe8f4;
  --bn-muted: #b6a7c0;
  --bn-accent: #ff8fa0;
  --bn-accent-2: #ffbaa0;
  --bn-accent-3: #4fd3c2;
  --bn-border: #3a2d4a;
  --bn-shadow: 0 14px 34px rgba(0, 0, 0, .45);
  --bn-shadow-sm: 0 4px 14px rgba(0, 0, 0, .35);
  --bn-input-bg: #2a2138;
  --bn-track: #3a2d4a;
}

.bn * { box-sizing: border-box; }

.bn-wrap {
  max-width: 980px;
  margin: 0 auto;
  padding: 0 18px;
}

/* 顶部 Hero */
.bn-hero {
  text-align: center;
  padding: 14px 12px 26px;
}
.bn-hero h1 {
  margin: 0 0 10px;
  font-size: 30px;
  line-height: 1.25;
  letter-spacing: .5px;
  background: linear-gradient(120deg, var(--bn-accent), var(--bn-accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.bn-hero p {
  margin: 0 auto;
  max-width: 640px;
  color: var(--bn-muted);
  font-size: 15px;
  line-height: 1.7;
}
.bn-badges {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 8px;
  margin-top: 16px;
}
.bn-badge {
  font-size: 12.5px;
  padding: 5px 12px;
  border-radius: 999px;
  background: var(--bn-card-2);
  border: 1px solid var(--bn-border);
  color: var(--bn-text);
}

/* 主体网格 */
.bn-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  align-items: start;
}
@media (max-width: 760px) {
  .bn-grid { grid-template-columns: 1fr; }
}

.bn-card {
  background: var(--bn-card);
  border: 1px solid var(--bn-border);
  border-radius: 22px;
  padding: 22px 22px 24px;
  box-shadow: var(--bn-shadow);
}
.bn-card-title {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 17px;
  font-weight: 700;
  margin: 0 0 18px;
}

/* 表单 */
.bn-field { margin-bottom: 18px; }
.bn-field > label {
  display: block;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 8px;
}
.bn-input-wrap {
  position: relative;
  display: flex;
  align-items: center;
}
.bn-input {
  width: 100%;
  height: 50px;
  padding: 0 64px 0 16px;
  font-size: 18px;
  color: var(--bn-text);
  background: var(--bn-input-bg);
  border: 1.5px solid var(--bn-border);
  border-radius: 14px;
  outline: none;
  transition: border-color .15s, box-shadow .15s;
}
.bn-input:focus {
  border-color: var(--bn-accent);
  box-shadow: 0 0 0 4px rgba(255, 122, 138, .16);
}
.bn-input::-webkit-outer-spin-button,
.bn-input::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
.bn-input[type=number] { -moz-appearance: textfield; }
.bn-suffix {
  position: absolute;
  right: 16px;
  font-size: 14px;
  color: var(--bn-muted);
  pointer-events: none;
}
.bn-help {
  margin: 8px 0 0;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--bn-muted);
}

/* 滑块 */
.bn-range-row { display: flex; align-items: center; gap: 12px; }
.bn-range {
  -webkit-appearance: none;
  appearance: none;
  flex: 1;
  height: 6px;
  border-radius: 999px;
  background: var(--bn-track);
  outline: none;
}
.bn-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--bn-accent), var(--bn-accent-2));
  border: 3px solid #fff;
  box-shadow: var(--bn-shadow-sm);
  cursor: pointer;
}
[data-theme="dark"] .bn-range::-webkit-slider-thumb { border-color: #2a2138; }
.bn-range::-moz-range-thumb {
  width: 20px; height: 20px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--bn-accent), var(--bn-accent-2));
  border: 3px solid #fff;
  cursor: pointer;
}
.bn-range-val {
  min-width: 92px;
  text-align: center;
  font-weight: 700;
  font-size: 15px;
  color: var(--bn-accent);
}

/* 按钮 */
.bn-btn {
  height: 50px;
  border: none;
  border-radius: 14px;
  font-size: 16px;
  font-weight: 700;
  cursor: pointer;
  transition: transform .12s, box-shadow .15s, opacity .15s;
}
.bn-btn:active { transform: translateY(1px); }
.bn-btn-primary {
  width: 100%;
  color: #fff;
  background: linear-gradient(120deg, var(--bn-accent), var(--bn-accent-2));
  box-shadow: var(--bn-shadow-sm);
}
.bn-btn-primary:hover { box-shadow: 0 8px 22px rgba(255, 122, 138, .35); }
.bn-btn-ghost {
  width: 100%;
  margin-top: 10px;
  color: var(--bn-accent);
  background: var(--bn-card-2);
  border: 1.5px solid var(--bn-border);
}
.bn-btn-row { display: flex; gap: 10px; margin-top: 10px; }
.bn-btn-row .bn-btn { flex: 1; height: 44px; font-size: 14px; }

.bn-err {
  margin-top: 12px;
  padding: 10px 14px;
  border-radius: 12px;
  background: rgba(255, 90, 110, .1);
  border: 1px solid rgba(255, 90, 110, .35);
  color: #d6445a;
  font-size: 13.5px;
}
[data-theme="dark"] .bn-err { color: #ff9bab; background: rgba(255, 90, 110, .16); }

/* 结果区 */
.bn-empty {
  text-align: center;
  padding: 40px 10px;
  color: var(--bn-muted);
}
.bn-empty .bn-emoji { font-size: 46px; }
.bn-empty p { margin-top: 12px; font-size: 14px; line-height: 1.7; }

.bn-result[hidden] { display: none; }

.bn-hero-num {
  text-align: center;
  padding: 18px 0 6px;
}
.bn-hero-num .bn-label { font-size: 13px; color: var(--bn-muted); }
.bn-hero-num .bn-big {
  font-size: 44px;
  font-weight: 800;
  line-height: 1.1;
  background: linear-gradient(120deg, var(--bn-accent), var(--bn-accent-2));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.bn-hero-num .bn-big small { font-size: 16px; font-weight: 700; margin-left: 4px; }
.bn-hero-num .bn-sub { font-size: 13px; color: var(--bn-muted); margin-top: 6px; }

.bn-metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-top: 14px;
}
.bn-metric {
  background: var(--bn-card-2);
  border: 1px solid var(--bn-border);
  border-radius: 16px;
  padding: 14px;
}
.bn-metric .k { display: block; font-size: 12.5px; color: var(--bn-muted); margin-bottom: 6px; }
.bn-metric .v { font-size: 20px; font-weight: 800; }
.bn-metric.is-iron .v { color: var(--bn-accent-3); }
.bn-metric.is-energy .v { color: var(--bn-accent-2); }
.bn-metric .v small { font-size: 13px; font-weight: 600; color: var(--bn-muted); margin-left: 2px; }

.bn-subhead {
  margin: 22px 0 10px;
  font-size: 15px;
  font-weight: 700;
}
.bn-note {
  background: var(--bn-card-2);
  border-left: 4px solid var(--bn-accent);
  border-radius: 12px;
  padding: 12px 14px;
  font-size: 13px;
  line-height: 1.7;
  color: var(--bn-text);
}

/* 拆解列表 */
.bn-bill { list-style: none; margin: 10px 0 0; padding: 0; }
.bn-bill li {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 9px 2px;
  border-bottom: 1px dashed var(--bn-border);
  font-size: 14px;
}
.bn-bill li:last-child { border-bottom: none; }
.bn-bill .bk { color: var(--bn-muted); }
.bn-bill .bv { font-weight: 700; text-align: right; }

/* 参考表 */
.bn-tables { margin-top: 22px; display: grid; gap: 18px; }
.bn-table-card {
  background: var(--bn-card);
  border: 1px solid var(--bn-border);
  border-radius: 22px;
  padding: 20px 22px 22px;
  box-shadow: var(--bn-shadow);
}
.bn-table-card h2 { margin: 0 0 4px; font-size: 17px; }
.bn-table-card .bn-help { margin-bottom: 12px; }
.bn-table-scroll { overflow-x: auto; }
.bn-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13.5px;
}
.bn-table th, .bn-table td {
  padding: 10px 12px;
  text-align: left;
  border-bottom: 1px solid var(--bn-border);
  white-space: nowrap;
}
.bn-table th { color: var(--bn-muted); font-weight: 600; background: var(--bn-card-2); }
.bn-table tr:last-child td { border-bottom: none; }
.bn-table .hl { color: var(--bn-accent); font-weight: 700; }

/* AI 解读 */
.bn-ai { margin-top: 16px; }
.bn-ai-box {
  margin-top: 12px;
  min-height: 56px;
  padding: 14px 16px;
  border-radius: 16px;
  background: var(--bn-card-2);
  border: 1px solid var(--bn-border);
  font-size: 14px;
  line-height: 1.8;
  white-space: pre-wrap;
  color: var(--bn-text);
}
.bn-ai-box:empty::before {
  content: "点击上方按钮，让 AI 结合本次结果给出喂养与营养搭配建议。";
  color: var(--bn-muted);
}
.bn-ai-box.bn-ai-err { color: #d6445a; border-color: rgba(255,90,110,.35); }
[data-theme="dark"] .bn-ai-box.bn-ai-err { color: #ff9bab; }

/* 免责声明 */
.bn-disclaim {
  margin-top: 24px;
  padding: 16px 18px;
  border-radius: 16px;
  background: var(--bn-card-2);
  border: 1px solid var(--bn-border);
  font-size: 13px;
  line-height: 1.8;
  color: var(--bn-muted);
}
.bn-disclaim b { color: var(--bn-text); }

/* 信息 / FAQ */
.bn-info { margin-top: 26px; }
.bn-info h1 { font-size: 22px; margin: 0 0 14px; }
.bn-chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 6px 0 18px; }
.bn-chip {
  font-size: 12.5px;
  padding: 6px 12px;
  border-radius: 999px;
  background: var(--bn-card);
  border: 1px solid var(--bn-border);
  color: var(--bn-text);
}
.bn-chip::before { content: "●"; color: var(--bn-accent); margin-right: 6px; font-size: 9px; vertical-align: middle; }
.bn-prose { font-size: 14.5px; line-height: 1.9; color: var(--bn-text); }
.bn-prose b { color: var(--bn-accent); }
.bn-prose p { margin: 0 0 12px; }

.bn-faq-item {
  border: 1px solid var(--bn-border);
  border-radius: 14px;
  padding: 4px 16px;
  margin-bottom: 10px;
  background: var(--bn-card);
}
.bn-faq-item summary {
  cursor: pointer;
  font-weight: 700;
  font-size: 14.5px;
  padding: 12px 0;
  list-style: none;
}
.bn-faq-item summary::-webkit-details-marker { display: none; }
.bn-faq-item summary::after { content: "＋"; float: right; color: var(--bn-accent); font-weight: 700; }
.bn-faq-item[open] summary::after { content: "－"; }
.bn-faq-a { padding: 0 0 14px; font-size: 14px; line-height: 1.85; color: var(--bn-text); }

.bn-meta {
  display: flex; flex-wrap: wrap; gap: 10px; margin-top: 16px;
}
.bn-meta .item {
  flex: 1 1 140px;
  background: var(--bn-card-2);
  border: 1px solid var(--bn-border);
  border-radius: 14px;
  padding: 12px 14px;
}
.bn-meta .k { display: block; font-size: 12px; color: var(--bn-muted); margin-bottom: 4px; }
.bn-meta .v { font-weight: 700; font-size: 14px; }

.bn-back {
  position: fixed;
  right: 22px; bottom: 26px;
  width: 46px; height: 46px;
  border-radius: 50%;
  border: none;
  background: linear-gradient(135deg, var(--bn-accent), var(--bn-accent-2));
  color: #fff; font-size: 20px;
  cursor: pointer;
  box-shadow: var(--bn-shadow);
  opacity: 0; pointer-events: none;
  transition: opacity .25s;
  z-index: 30;
}
.bn-back.show { opacity: 1; pointer-events: auto; }