:root{
  --bg:#f5f7fb;--card:#fff;--text:#172033;--muted:#667085;--line:#e5e7eb;
  --accent:#2563eb;--accent-soft:#eff6ff;--good:#0f766e;--shadow:0 14px 36px rgba(15,23,42,.08);
  --radius:18px
}
*{box-sizing:border-box}
body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;background:linear-gradient(180deg,#eef4ff 0,#f8fafc 240px,#f5f7fb 100%);color:var(--text)}
.wrap{max-width:1180px;margin:0 auto;padding:34px 18px 60px}
.hero{display:flex;justify-content:space-between;gap:24px;align-items:flex-end;margin-bottom:22px}
.hero h1{margin:8px 0 0;font-size:clamp(34px,6vw,56px);letter-spacing:-.04em}
.hero p{margin:12px 0 0;color:#526581;max-width:780px;line-height:1.7;font-size:17px}
.pill{display:inline-flex;padding:5px 10px;border-radius:999px;background:#ecfdf5;color:var(--good);font-size:12px;font-weight:800}
.badge{background:#111827;color:#fff;padding:8px 12px;border-radius:999px;font-size:12px;white-space:nowrap}
.grid{display:grid;grid-template-columns:1.05fr .95fr;gap:20px}
.card{background:var(--card);border:1px solid rgba(229,231,235,.9);border-radius:var(--radius);box-shadow:var(--shadow);padding:22px}
.card h2{margin:0 0 18px;font-size:18px}
.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.full{grid-column:1/-1}
label{display:block;font-size:13px;font-weight:700;margin-bottom:7px}
input,select{width:100%;padding:12px 13px;border:1px solid #d0d5dd;border-radius:12px;background:#fff;color:#111827;font-size:16px;outline:none}
input:focus,select:focus{border-color:#93c5fd;box-shadow:0 0 0 4px #dbeafe}
.hidden{display:none!important}
.hint{font-size:12px;color:var(--muted);margin-top:6px}
.seg{display:grid;grid-template-columns:repeat(3,1fr);border:1px solid #d0d5dd;border-radius:12px;overflow:hidden}
.seg button{padding:12px;border:0;background:#fff;cursor:pointer;font-weight:750}
.seg button.active{background:var(--accent-soft);color:var(--accent)}
.calculate-btn{width:100%;min-height:46px;border:0;border-radius:12px;background:#172033;color:#fff;font-size:15px;font-weight:800;cursor:pointer}
.calculate-btn:disabled{opacity:.55;cursor:wait}
.city-picker{position:relative}
.city-picker::after{content:"⌄";position:absolute;right:14px;top:10px;pointer-events:none;color:#475467;font-size:18px;font-weight:800}
.city-search{padding-right:38px}
.city-options{position:absolute;left:0;right:0;top:calc(100% + 6px);z-index:30;max-height:280px;overflow:auto;background:#fff;border:1px solid #d0d5dd;border-radius:12px;box-shadow:0 14px 34px rgba(15,23,42,.14);padding:6px}
.city-option{width:100%;border:0;background:#fff;border-radius:9px;padding:10px 11px;display:flex;align-items:center;justify-content:space-between;gap:10px;text-align:left;cursor:pointer;color:#172033;font-size:14px}
.city-option:hover,.city-option.active{background:#eff6ff;color:#1d4ed8}
.city-option-en{font-weight:750}.city-option-zh{color:#667085;white-space:nowrap}
.note{margin-top:18px;padding:14px 16px;border-radius:14px;background:#fffbeb;border:1px solid #fde68a;color:#854d0e;font-size:13px;line-height:1.6}
.custom-city-panel{margin-top:18px;padding:18px;border-radius:15px;background:#f8fafc;border:1px solid #dbeafe}
.custom-city-head{display:flex;justify-content:space-between;gap:14px;align-items:flex-start;margin-bottom:14px}
.custom-city-title{font-size:16px;font-weight:850}.close-city-btn{width:34px;height:34px;border-radius:9px;border:1px solid #d0d5dd;background:#fff;color:#475467;font-size:22px;cursor:pointer}
.custom-city-grid{display:grid;grid-template-columns:1fr 1fr;gap:13px}
.adjust-row{display:flex;align-items:center;gap:8px}.adjust-row input{flex:1}.adjust-row span{font-weight:800}
.custom-city-warning{margin-top:14px;padding:11px 12px;border-radius:10px;background:#fffbeb;border:1px solid #fde68a;color:#854d0e;font-size:12px;line-height:1.55}
.custom-city-actions{display:flex;justify-content:flex-end;gap:9px;margin-top:14px}
.primary-btn,.secondary-btn{min-height:42px;padding:9px 14px;border-radius:10px;font-size:13px;font-weight:800;cursor:pointer}
.primary-btn{border:1px solid #2563eb;background:#2563eb;color:#fff}.secondary-btn{border:1px solid #d0d5dd;background:#fff;color:#344054}
.error{margin-top:10px;color:#b42318;font-size:13px}
.empty-state{padding:42px 18px;border:1px dashed #cbd5e1;border-radius:16px;color:#667085;text-align:center;line-height:1.6}
.result-main{background:linear-gradient(135deg,#eff6ff,#f8fafc);border:1px solid #dbeafe;border-radius:16px;padding:20px;margin-bottom:16px}
.eyebrow{font-size:12px;text-transform:uppercase;letter-spacing:.08em;color:#64748b;font-weight:800}
.result-lead{margin-top:10px;font-size:18px;font-weight:750;line-height:1.45;color:#24324a}
.result-value-row{display:flex;align-items:flex-end;gap:12px;flex-wrap:wrap;margin:8px 0 2px}
.big{font-size:clamp(34px,6vw,58px);font-weight:850;letter-spacing:-.05em;margin:0;line-height:1.05}
.approx-mark{font-size:.43em;font-weight:800;letter-spacing:0;margin-right:8px;vertical-align:middle;color:#526581}
.result-unit-select{width:auto;min-width:106px;padding:9px 34px 9px 11px;margin-bottom:5px;border:1px solid #bfdbfe;border-radius:10px;background:#fff;color:#1e3a5f;font-size:15px;font-weight:750}
.result-caption{font-size:20px;font-weight:760;color:#24324a;margin-bottom:12px}
.credibility-row{display:grid;grid-template-columns:1.5fr .8fr;gap:10px;margin:14px 0 12px}
.range-box,.confidence-box{background:#fff;border:1px solid #dbeafe;border-radius:12px;padding:12px 14px}
.range-label{font-size:12px;color:#667085;margin-bottom:5px}.range-value{font-size:18px;font-weight:800}
.confidence-badge{display:inline-flex;align-items:center;padding:5px 10px;border-radius:999px;background:#ecfdf5;color:#0f766e;font-weight:800;font-size:13px}
.confidence-badge.medium{background:#fffbeb;color:#a16207}.confidence-badge.low{background:#fef2f2;color:#b91c1c}
.hour-note{font-size:12px;color:var(--muted);margin:4px 0 10px}
.sub{color:var(--muted);font-size:14px;line-height:1.6;padding-top:12px;border-top:1px solid #dbeafe}
.method-box{margin-top:14px;padding:14px 15px;border-radius:13px;background:rgba(255,255,255,.72);border:1px solid #dbeafe}
.method-title{font-size:13px;font-weight:800;color:#344054;margin-bottom:10px}
.method-grid{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.method-grid>div{padding:10px 11px;border-radius:10px;background:#f8fafc;border:1px solid #eef2f7}
.method-grid span{display:block;font-size:11px;color:#667085;margin-bottom:4px}.method-grid strong{font-size:15px}
.method-note{font-size:11px;color:#667085;line-height:1.55;margin-top:9px}
.metrics{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin-top:14px}
.metric{border:1px solid var(--line);border-radius:14px;padding:14px;background:#fff}.metric .k{font-size:12px;color:var(--muted)}.metric .v{font-weight:800;font-size:20px;margin-top:3px}
.bar-wrap{margin-top:18px}.bar-row{margin:13px 0}.bar-label{display:flex;justify-content:space-between;font-size:13px;margin-bottom:7px}
.bar{height:10px;background:#eef2f7;border-radius:999px;overflow:hidden}.bar>i{display:block;height:100%;width:0;background:linear-gradient(90deg,#60a5fa,#2563eb);border-radius:999px}
.methodology-card{margin-top:20px}.methodology-statement{margin:0;padding:16px 18px;border:1px solid var(--line);border-radius:13px;background:#fff;color:#475467;font-size:13px;line-height:1.8}.transparency-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:12px}
.transparency-grid>div{padding:14px;border:1px solid var(--line);border-radius:13px;background:#fff}
.transparency-grid strong{display:block;font-size:13px;margin-bottom:5px}.transparency-grid span{font-size:12px;line-height:1.55;color:#667085}
.footer{margin-top:16px;color:#667085;font-size:12px}
@media(max-width:850px){.grid{grid-template-columns:1fr}.hero{align-items:flex-start;flex-direction:column}.transparency-grid{grid-template-columns:1fr 1fr}}
@media(max-width:560px){.form-grid,.metrics,.custom-city-grid,.credibility-row,.method-grid,.transparency-grid{grid-template-columns:1fr}.full{grid-column:auto}.result-value-row{align-items:flex-start;flex-direction:column;gap:8px}}


.reference-block{margin-top:16px;padding:16px 18px;border:1px solid var(--line);border-radius:13px;background:#fff}
.reference-block h3{margin:0 0 10px;font-size:14px;color:var(--text)}
.reference-list{margin:0;padding-left:20px;color:#475467;font-size:12.5px;line-height:1.75}
.reference-list li{margin:5px 0}
.reference-note{margin:12px 0 0;padding-top:10px;border-top:1px dashed var(--line);color:#667085;font-size:12px;line-height:1.7}

.seo-intro{max-width:1180px;margin:0 auto 14px;padding:0 4px;color:#475467;font-size:13px;line-height:1.75}
.seo-intro p{margin:0}