/* ==========================================================================
   18 · 燃气采暖炉选型 —— HEAT LOAD SHEET
   独立设计：钢蓝技术图纸（细网格 + 尺寸线）；深色首屏速算台，
   功率为带刻度的横向标尺，铭牌是工程表格，安装为勾选清单。
   ========================================================================== */
.bsg {
    --hg-paper:      #f1f4f7;
    --hg-paper-2:    #e2e9f0;
    --hg-card:       #fbfdff;
    --hg-card-2:     #eef3f8;
    --hg-ink:        #182a3c;
    --hg-ink-2:      #40586e;
    --hg-ink-3:      #7c8fa1;
    --hg-line:       #cedbe6;
    --hg-line-2:     #a9bfd1;
    --hg-brand:      #33567a;
    --hg-brand-2:    #c07a3c;
    --hg-brand-soft: #dfeaf4;
    --hg-on-brand:   #f8fbff;
    --bsg-dark:      #16283a;
    --bsg-dark-2:    #1e3448;
    background: var(--hg-paper);
}
:root[data-theme="dark"] .bsg {
    --hg-paper:      #0e141a;
    --hg-paper-2:    #17212b;
    --hg-card:       #141e28;
    --hg-card-2:     #1b2835;
    --hg-ink:        #e8f0f7;
    --hg-ink-2:      #b1c3d3;
    --hg-ink-3:      #8298ab;
    --hg-line:       #2a3b4c;
    --hg-line-2:     #3b536a;
    --hg-brand:      #8db8e0;
    --hg-brand-2:    #e0ae74;
    --hg-brand-soft: #1c3043;
    --hg-on-brand:   #0d1822;
    --bsg-dark:      #0a1119;
    --bsg-dark-2:    #101d29;
}
.bsg .hg2-btn { border-radius: 2px; }

/* ---------- 首屏：技术图纸深色台 ---------- */
.bsg-hero { background: var(--bsg-dark); color: #e9f1f8; border-bottom: 4px solid var(--hg-brand); }
.bsg-hero-in { display: grid; grid-template-columns: minmax(0, 1.08fr) minmax(0, .92fr); max-width: 1180px; margin: 0 auto; }
.bsg-hero-copy { padding: 46px 44px 46px 26px; position: relative;
    background-image: linear-gradient(rgba(141, 184, 224, .06) 1px, transparent 1px), linear-gradient(90deg, rgba(141, 184, 224, .06) 1px, transparent 1px);
    background-size: 26px 26px; }
.bsg-kicker { display: inline-block; font: 700 11.5px/1.5 var(--hg-mono); letter-spacing: .18em; color: #9dc4e6; border-left: 3px solid #9dc4e6; padding-left: 10px; margin-bottom: 22px; }
.bsg-hero h1 { color: #f5f9fd; margin-bottom: 20px; }
.bsg-hero h1 em { color: #a8cef0; }
.bsg-lede { color: #c3d3e1; font-size: 15.5px; line-height: 1.95; max-width: 54ch; }
.bsg-lede b { color: #f5f9fd; box-shadow: inset 0 -.4em 0 rgba(141, 184, 224, .2); }
.bsg-points { list-style: none; margin: 24px 0 0; padding: 0; border-top: 1px solid #38526a; }
.bsg-points li { position: relative; padding: 9px 0 9px 24px; border-bottom: 1px solid #38526a; font-size: 13.5px; line-height: 1.75; color: #c3d3e1; margin: 0; }
.bsg-points li::before { content: '□'; position: absolute; left: 2px; top: 9px; color: #9dc4e6; font: 700 12px/1.6 var(--hg-mono); }
.bsg-points b { color: #f5f9fd; }
.bsg-hero-note { margin: 20px 0 0; font-size: 12.5px; line-height: 1.8; color: #8fa6ba; }

.bsg-quick { padding: 30px 26px 32px; background: var(--bsg-dark-2); border-left: 1px solid #38526a; }
.bsg-quick-hd { display: flex; align-items: center; justify-content: space-between; gap: 10px; font: 700 11.5px/1.5 var(--hg-mono); letter-spacing: .12em; color: #8fa6ba; }
.bsg-quick-hd b { color: #a8cef0; border: 1px solid #4a6780; padding: 2px 9px; font-size: 11px; }
.bsg-kw { display: flex; flex-direction: column; align-items: center; justify-content: center; padding: 20px 0 18px; border-bottom: 1px dashed #4a6780; text-align: center; }
.bsg-kw span { font: 700 11px/1.5 var(--hg-mono); letter-spacing: .14em; color: #8fa6ba; }
.bsg-kw strong { font: 700 clamp(34px, 6vw, 52px)/1.3 var(--hg-mono); letter-spacing: -.04em; color: #b6d8f5; }
.bsg-kw small { font-size: 12px; color: #c3d3e1; }
.bsg-quick-fields { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 18px; }
.bsg-span2 { grid-column: 1 / -1; }
.bsg-quick .hg2-label { color: #c3d3e1; }
.bsg-quick .hg2-hint { color: #8fa6ba; }
.bsg-quick input, .bsg-quick select { background-color: #14283a; color: #eef5fb; border-color: #4a6780; }
:root[data-theme="dark"] .bsg-quick input, :root[data-theme="dark"] .bsg-quick select { background-color: #14283a; color: #eef5fb; border-color: #4a6780; }
.bsg-quick-btns { display: flex; gap: 9px; flex-wrap: wrap; margin-top: 16px; }
.bsg-quick-btns .hg2-btn { flex: 1 1 auto; }

/* ---------- 功率刻度尺 ---------- */
.bsg-load, .bsg-result-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.bsg-card { background: var(--hg-card); border: 1px solid var(--hg-line); border-radius: 2px; padding: 20px 22px 22px; }
.bsg-card-hd { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; flex-wrap: wrap; padding-bottom: 12px; margin-bottom: 16px; border-bottom: 1px solid var(--hg-line); }
.bsg-card-hd h3 { font-family: var(--hg-display); font-size: 19px; }
.bsg-card-hd span { font: 11.5px/1.5 var(--hg-mono); color: var(--hg-ink-3); }
.bsg-scale { position: relative; height: 30px; border: 1px solid var(--hg-line-2); background: repeating-linear-gradient(90deg, var(--hg-card-2) 0 24px, var(--hg-line) 24px 25px); }
.bsg-scale i { position: absolute; top: -6px; bottom: -6px; left: 0; width: 3px; background: var(--hg-brand-2); transition: left .3s; }
.bsg-scale i::after { content: ''; position: absolute; top: -6px; left: -5px; border: 6px solid transparent; border-top-color: var(--hg-brand-2); }
.bsg-scale-ticks { display: flex; justify-content: space-between; margin-top: 8px; font: 11px/1.5 var(--hg-mono); color: var(--hg-ink-3); }
.bsg-factors { margin-top: 18px; display: grid; gap: 0; border-top: 1px solid var(--hg-line); }
.bsg-factors div { display: flex; align-items: center; justify-content: space-between; gap: 10px; padding: 8px 0; border-bottom: 1px solid var(--hg-line); font-size: 13px; color: var(--hg-ink-2); }
.bsg-factors b { font: 700 13px/1.5 var(--hg-mono); color: var(--hg-brand); }
.bsg-fields { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.bsg-hot-note { margin-top: 14px; padding: 11px 14px; background: var(--hg-card-2); border-left: 3px solid var(--hg-brand-2); font-size: 13px; line-height: 1.8; color: var(--hg-ink-2); }
.bsg-figure { margin-top: 16px; padding-top: 14px; border-top: 1px dashed var(--hg-line-2); text-align: center; }
.bsg-figure img { max-width: 100%; height: auto; display: block; margin: 0 auto 8px; }
.bsg-figure span { font: 11.5px/1.6 var(--hg-mono); color: var(--hg-ink-3); letter-spacing: .06em; }
.bsg-btn-row { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 18px; align-items: center; }
.bsg-main-btns { padding: 18px 0 0; }

/* ---------- 铭牌表 ---------- */
.bsg-models { border: 1px solid var(--hg-line); background: var(--hg-card); padding: 18px 20px 20px; }
.bsg-models .bsg-btn-row { margin: 0 0 14px; }
.bsg-model-tbl input[type="text"], .bsg-model-tbl input[type="number"] { min-height: 34px; padding: 5px 8px; font-size: 13px; }
.bsg-model-tbl select { min-height: 34px; padding: 5px 24px 5px 8px; font-size: 13px; background-position: calc(100% - 12px) 15px, calc(100% - 8px) 15px; }
.bsg-model-tbl th { font-size: 11.5px; white-space: nowrap; }
.bsg-model-tbl td { padding: 7px 8px; min-width: 92px; }
.bsg-model-tbl td:first-child { min-width: 96px; }
.bsg-model-tbl .hg2-btn { min-height: 30px; padding: 4px 10px; font-size: 12px; }

/* ---------- 安装清单 ---------- */
.bsg-install { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--hg-line); border: 1px solid var(--hg-line); }
.bsg-inst { display: flex; gap: 10px; align-items: flex-start; padding: 14px 16px; background: var(--hg-card); cursor: pointer; }
.bsg-inst:hover { background: var(--hg-card-2); }
.bsg-inst.is-on { background: var(--hg-brand-soft); }
.bsg-inst input { margin: 3px 0 0; width: 15px; height: 15px; accent-color: var(--hg-brand); flex: none; }
.bsg-inst b { display: block; font-size: 13.5px; color: var(--hg-ink); }
.bsg-inst span { display: block; font-size: 12px; line-height: 1.7; color: var(--hg-ink-3); margin-top: 2px; }
.bsg-install-out { margin-top: 14px; padding: 13px 16px; border: 1px solid var(--hg-line); border-left: 4px solid var(--hg-brand-2); background: var(--hg-card); font-size: 13.5px; line-height: 1.85; color: var(--hg-ink-2); }
.bsg-install-out b { color: var(--hg-ink); }

/* ---------- 结果 ---------- */
.bsg-kpis { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1px; background: var(--hg-line); border: 1px solid var(--hg-line); margin-bottom: 18px; }
.bsg-kpi { background: var(--hg-card); padding: 16px 18px; }
.bsg-kpi span { display: block; font-size: 12px; color: var(--hg-ink-3); }
.bsg-kpi strong { display: block; font: 700 22px/1.4 var(--hg-mono); color: var(--hg-brand); margin-top: 4px; }
.bsg-kpi small { display: block; font-size: 11.5px; color: var(--hg-ink-3); }
.bsg-todo { margin: 0; padding-left: 1.3em; font-size: 13.5px; line-height: 1.9; color: var(--hg-ink-2); }
.bsg-todo li { margin-bottom: 8px; }
.bsg-todo b, .bsg-ask b { color: var(--hg-ink); }
.bsg-ask p { padding-left: 14px; border-left: 2px solid var(--hg-brand-soft); margin-bottom: 9px; font-size: 13.5px; line-height: 1.85; }
.bsg-result-btns { padding-top: 18px; border-top: 1px solid var(--hg-line); margin-top: 22px; }

/* ---------- 批量 ---------- */
.bsg-batch { border: 1px solid var(--hg-line); background: var(--hg-card); padding: 20px 22px; }
.bsg-clean { display: flex; flex-wrap: wrap; align-items: center; gap: 7px; margin-top: 14px; }
.bsg-clean > b { width: 100%; font-size: 12.5px; color: var(--hg-ink-2); }
.bsg-preview { width: 100%; margin-top: 6px; padding: 8px 10px; background: var(--hg-card-2); font: 12px/1.7 var(--hg-mono); color: var(--hg-ink-3); word-break: break-all; }
.bsg-batch-tbl { margin-top: 16px; }

@media (max-width: 980px) {
    .bsg-hero-in, .bsg-load, .bsg-result-cols { grid-template-columns: 1fr; }
    .bsg-hero-copy { padding-right: 26px; padding-bottom: 30px; }
    .bsg-quick { border-left: 0; border-top: 1px solid #38526a; }
    .bsg-install, .bsg-kpis { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
    .bsg-quick-fields, .bsg-fields, .bsg-install, .bsg-kpis { grid-template-columns: 1fr; }
    .bsg-span2 { grid-column: auto; }
    .bsg-kw strong { font-size: 32px; }
}