/* 工程计算工具箱 · 站点样式（无外部依赖） */
:root{--navy:#18324f;--navy2:#22426a;--navy3:#0f2238;--pri:#1f5fae;--pri2:#e8f0fb;--bg:#f3f5f8;--card:#fff;--line:#d9dee6;--text:#1f2733;--muted:#6b7686;--ok:#1e7b34;--okbg:#e8f5ec;--warn:#b35c00;--warnbg:#fff4e5;--gold:#c98a12}
*{box-sizing:border-box}
[hidden]{display:none!important}
html,body{margin:0;padding:0}
body{font-family:"Microsoft YaHei","微软雅黑","PingFang SC","Noto Sans CJK SC","Source Han Sans SC","WenQuanYi Micro Hei",SimHei,Arial,sans-serif;background:var(--bg);color:var(--text);font-size:14px;line-height:1.6}
a{color:var(--pri);text-decoration:none}
a:hover{text-decoration:underline}
.demo-ribbon{background:#fff4e5;color:#7a4300;border-bottom:1px solid #f0d3a8;font-size:12px;text-align:center;padding:4px 10px}
.site-header{background:var(--navy);color:#fff}
.site-header .in{max-width:1180px;margin:0 auto;padding:12px 24px;display:flex;align-items:center;gap:18px}
.brand{display:flex;align-items:center;gap:10px;color:#fff;font-weight:600;font-size:18px;letter-spacing:.5px}
.brand:hover{text-decoration:none}
.logo{width:30px;height:30px;border-radius:6px;background:linear-gradient(135deg,#2f74c8,#0f7d74);display:flex;align-items:center;justify-content:center;font-size:15px;font-weight:700;color:#fff}
.brand small{display:block;font-size:11px;color:#b9c8da;font-weight:400;letter-spacing:0}
.nav{display:flex;gap:4px;margin-left:12px}
.nav a{color:#cfdbe9;padding:6px 12px;border-radius:4px;font-size:14px}
.nav a:hover,.nav a.on{background:var(--navy2);color:#fff;text-decoration:none}
.hd-right{margin-left:auto;display:flex;align-items:center;gap:10px}
.badge{display:inline-block;font-size:12px;padding:2px 9px;border-radius:10px;line-height:18px;white-space:nowrap}
.badge.free{background:#2a4a70;color:#cfe0f5;border:1px solid #3d5f88}
.badge.pro{background:linear-gradient(135deg,#e7b649,#c98a12);color:#3a2600;font-weight:600;border:1px solid #f0c860}
.badge.live{background:var(--okbg);color:var(--ok);border:1px solid #b9dcc3}
.badge.soon{background:#eef1f5;color:#6b7686;border:1px solid #d9dee6}
.btn{font-family:inherit;font-size:14px;border:1px solid #c5cdd8;background:#fff;color:var(--text);padding:7px 16px;border-radius:4px;cursor:pointer;display:inline-block;line-height:1.4}
.btn:hover{background:#f4f6f9;text-decoration:none}
.btn.pri{background:var(--pri);border-color:var(--pri);color:#fff}
.btn.pri:hover{background:#174d8f}
.btn.ghost{background:var(--navy2);border-color:#3d5878;color:#fff}
.btn.ghost:hover{background:#2c5585}
.btn.sm{font-size:13px;padding:5px 12px}
.btn.gold{background:#c98a12;border-color:#c98a12;color:#fff}
.btn.gold:hover{background:#a97208}
.btn:disabled{opacity:.55;cursor:not-allowed}
.wrap{max-width:1180px;margin:0 auto;padding:0 24px}
.hero{background:linear-gradient(180deg,var(--navy) 0%,#1d3c5f 100%);color:#fff;padding:40px 0 48px}
.hero h1{margin:0 0 8px;font-size:30px;font-weight:600;letter-spacing:1px}
.hero p{margin:0;color:#c7d5e6;font-size:15px;max-width:720px}
.hero .chips{margin-top:18px;display:flex;gap:8px;flex-wrap:wrap}
.hero .chips span{background:rgba(255,255,255,.08);border:1px solid rgba(255,255,255,.18);padding:3px 12px;border-radius:14px;font-size:13px;color:#dfe8f3}
section{padding:36px 0 8px}
.sec-h{display:flex;align-items:baseline;gap:12px;margin-bottom:16px}
.sec-h h2{margin:0;font-size:20px;font-weight:600}
.sec-h .sub{color:var(--muted);font-size:13px}
.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:16px}
.card{background:var(--card);border:1px solid var(--line);border-radius:8px;padding:18px;display:flex;flex-direction:column;gap:10px;transition:box-shadow .15s,transform .15s;color:var(--text)}
a.card:hover{box-shadow:0 6px 18px rgba(24,50,79,.12);transform:translateY(-2px);text-decoration:none}
.card .top{display:flex;align-items:center;justify-content:space-between}
.ico{width:42px;height:42px;border-radius:8px;display:flex;align-items:center;justify-content:center;background:var(--pri2);color:var(--pri)}
.ico svg{width:26px;height:26px}
.card h3{margin:0;font-size:16px;font-weight:600}
.card p{margin:0;color:var(--muted);font-size:13px;flex:1}
.card .go{font-size:13px;color:var(--pri)}
.card.feature{grid-column:span 2;border-color:#9fbde3;background:linear-gradient(135deg,#fff 60%,#eef4fc)}
.card.feature h3{font-size:18px}
.card.dim{opacity:.92}
.card.dim .ico{background:#eef1f5;color:#8592a3}
.card.dim .go{color:var(--muted)}
.feat-list{margin:0;padding-left:18px;color:#3a4656;font-size:13px}
.price-grid{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.price{background:#fff;border:1px solid var(--line);border-radius:8px;padding:20px 18px;display:flex;flex-direction:column;gap:8px}
.price.hl{border:2px solid var(--pri);box-shadow:0 6px 18px rgba(31,95,174,.12);position:relative}
.price.hl::before{content:"推荐";position:absolute;top:-11px;right:14px;background:var(--pri);color:#fff;font-size:12px;padding:1px 10px;border-radius:10px}
.price h3{margin:0;font-size:16px}
.price .amt{font-size:26px;font-weight:700;color:var(--navy)}
.price .amt small{font-size:13px;color:var(--muted);font-weight:400}
.price ul{margin:4px 0 8px;padding-left:18px;color:#3a4656;font-size:13px;flex:1}
.note{font-size:12px;color:var(--muted)}
.site-footer{margin-top:44px;background:var(--navy3);color:#9fb0c5;font-size:13px}
.site-footer .in{max-width:1180px;margin:0 auto;padding:22px 24px;display:flex;gap:24px;flex-wrap:wrap;justify-content:space-between}
.site-footer a{color:#c7d5e6}
/* modal */
.mask{position:fixed;inset:0;background:rgba(10,22,38,.55);display:none;align-items:center;justify-content:center;z-index:100}
.mask.show{display:flex}
.modal{background:#fff;border-radius:10px;width:min(640px,94vw);max-height:92vh;overflow:auto;box-shadow:0 20px 50px rgba(0,0,0,.3)}
.modal .mh{background:var(--navy);color:#fff;padding:12px 18px;display:flex;align-items:center;justify-content:space-between;border-radius:10px 10px 0 0}
.modal .mh h3{margin:0;font-size:16px;font-weight:600}
.modal .x{background:none;border:none;color:#cfdbe9;font-size:20px;cursor:pointer;line-height:1}
.modal .mb{padding:18px}
.toast{position:fixed;left:50%;top:70px;transform:translateX(-50%);background:#1f2733;color:#fff;padding:8px 18px;border-radius:6px;font-size:13px;z-index:200;display:none}
@media(max-width:900px){.price-grid{grid-template-columns:repeat(2,1fr)}.card.feature{grid-column:auto}.nav{display:none}}
/* ===== 广告位（示意）· 仅占位，无真实广告代码 ===== */
.ad-slot{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:2px;
  border:1px dashed #aab4c2;border-radius:4px;color:#7b8796;font-size:12px;line-height:1.5;
  background:repeating-linear-gradient(45deg,#f6f7f9,#f6f7f9 10px,#eceff3 10px,#eceff3 20px)}
.ad-slot::before{content:"广告";position:absolute;top:3px;left:6px;font-size:11px;color:#8a95a3;letter-spacing:1px}
.ad-slot b{color:#5d6878;font-size:13px;font-weight:600}
.ad-slot .sz{font-family:Consolas,monospace;color:#4a6a92;font-size:12px}
.ad-slot .why{font-size:11px;color:#98a2af;max-width:90%}
/* 广告与可点击元素之间留白，防止误点 */
.ad-gap{padding:20px 0}
.ad-anchor{position:fixed;left:0;right:0;bottom:0;z-index:90;background:#fff;border-top:1px solid #c9d1dc;box-shadow:0 -2px 8px rgba(0,0,0,.08);padding:6px 40px 6px 8px;display:none}
.ad-anchor .ad-slot{height:56px;margin:0 auto;max-width:336px}
.ad-anchor .ad-x{position:absolute;right:6px;top:50%;transform:translateY(-50%);width:28px;height:28px;border-radius:50%;border:1px solid #c5cdd8;background:#fff;color:#4a5566;font-size:16px;line-height:1;cursor:pointer}
@media(max-width:999px){.ad-anchor.on{display:block}}
.is-member .ad-slot,.is-member .ad-anchor,.is-member .ad-wrap{display:none!important}
@media(max-width:600px){.brand small{display:none}.site-header .in{padding:10px 14px;gap:10px}.hd-right .btn{white-space:nowrap;padding:5px 10px}.brand{font-size:16px}}

/* ===== 真实后端版新增 ===== */
.demo-ribbon.notice-info{background:#e8f0fb;color:#174d8f;border-bottom-color:#c4d6ef}
.demo-ribbon.notice-warn{background:#fff4e5;color:#7a4300;border-bottom-color:#f0d3a8}
.demo-ribbon.notice-success{background:#e8f5ec;color:#1e7b34;border-bottom-color:#b9dcc3}
.btn.wide{width:100%;padding:9px 16px;margin-top:4px}
.fm{display:flex;flex-direction:column;gap:10px}
.fm label{display:flex;flex-direction:column;gap:4px;font-size:13px;color:#3a4656;font-weight:600}
.fm input,.fm select,.fm textarea{font-family:inherit;font-size:14px;padding:8px 10px;border:1px solid #c5cdd8;border-radius:4px;font-weight:400;color:var(--text)}
.fm input:focus,.fm select:focus,.fm textarea:focus{outline:2px solid #9fc0ea;border-color:var(--pri)}
.tabs2{display:flex;border-bottom:1px solid var(--line);margin-bottom:14px}
.tabs2 a{flex:1;text-align:center;padding:8px 0;cursor:pointer;color:var(--muted);border-bottom:2px solid transparent;margin-bottom:-1px}
.tabs2 a:hover{text-decoration:none;color:var(--pri)}
.tabs2 a.on{color:var(--pri);border-bottom-color:var(--pri);font-weight:600}
.msg{font-size:13px;min-height:18px}
.msg.err{color:#b3261e}.msg.ok{color:var(--ok)}
.opts{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:12px}
.opt{border:1px solid var(--line);border-radius:8px;padding:14px;cursor:pointer;background:#fff;text-align:left;font-family:inherit;font-size:14px;color:var(--text)}
.opt:hover{border-color:var(--pri);box-shadow:0 4px 12px rgba(31,95,174,.12)}
.opt:disabled{opacity:.6;cursor:not-allowed;box-shadow:none;border-color:var(--line)}
.opt h4{margin:0 0 4px;font-size:15px}.opt p{margin:0;color:var(--muted);font-size:13px}
.opt.b{border-color:#efd391;background:#fffbf0}
.adbox{position:relative;margin:6px 0 12px;height:210px;border:2px dashed #b8c2cf;border-radius:8px;background:repeating-linear-gradient(45deg,#f7f8fa,#f7f8fa 14px,#eef1f5 14px,#eef1f5 28px);display:flex;flex-direction:column;align-items:center;justify-content:center;color:#6b7686;text-align:center}
.adbox .adtag{position:absolute;top:6px;left:8px;font-size:11px;background:#fff;border:1px solid #c5cdd8;border-radius:3px;padding:0 6px}
.adbox .adc{font-size:13px;margin-bottom:6px}
.adbox .cd{font-size:44px;font-weight:700;color:var(--navy);font-family:Consolas,monospace;line-height:1.2}
.pay{display:grid;grid-template-columns:190px 1fr;gap:18px;align-items:start}
.pay .qr{width:190px;height:190px;border:1px solid var(--line);border-radius:8px;background:#fff;display:flex;align-items:center;justify-content:center;overflow:hidden}
.pay .qr img{width:100%;height:100%;object-fit:contain}
.kv{font-size:13px;margin:0 0 10px}
.acct{display:flex;align-items:center;gap:8px;margin:4px 0 12px}
.acct code{font-family:Consolas,monospace;font-size:17px;font-weight:700;background:#f3f5f8;border:1px solid var(--line);padding:3px 12px;border-radius:4px;letter-spacing:1px}
.steps{margin:0 0 10px;padding-left:18px;font-size:13px;color:#3a4656}
.act{display:flex;gap:8px}
.act input{flex:1;font-family:Consolas,monospace;font-size:14px;padding:7px 10px;border:1px solid #c5cdd8;border-radius:4px;text-transform:uppercase}
.ptab{width:100%;border-collapse:collapse;font-size:13px;margin-top:4px}
.ptab td{border-top:1px solid #eef1f5;padding:5px 2px}
.ptab td.pr{text-align:right;white-space:nowrap;font-weight:700;color:var(--navy);font-size:15px}
.ptab td.pr small{font-weight:400;color:var(--muted);font-size:12px}
.foot2{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:12px;padding-top:12px;border-top:1px solid #eef1f5}
.okbar{background:#fdf5e1;border:1px solid #efd391;color:#7a5200;border-radius:6px;padding:6px 12px;font-size:13px;margin-bottom:12px}
.back{font-size:13px;margin-top:12px;display:inline-block;cursor:pointer;color:var(--pri)}
.done{text-align:center;padding:10px 0}
.done .ok{font-size:42px;color:var(--ok);line-height:1.2}
.done h3{margin:4px 0}
@media(max-width:600px){.pay{grid-template-columns:1fr}.pay .qr{margin:0 auto}.opts{grid-template-columns:1fr}}
/* 用户中心 */
.uc{display:grid;grid-template-columns:1fr 1fr;gap:16px;margin-top:20px}
.panel{background:#fff;border:1px solid var(--line);border-radius:8px;padding:18px 20px}
.panel h2{margin:0 0 12px;font-size:16px;font-weight:600;display:flex;align-items:center;gap:8px}
.panel.full{grid-column:1/-1}
.uidbig{font-family:Consolas,monospace;font-size:26px;font-weight:700;color:var(--navy);letter-spacing:1px}
.tbl{width:100%;border-collapse:collapse;font-size:13px}
.tbl th{text-align:left;color:#4a5566;background:#f6f8fb;padding:7px 8px;border-bottom:1px solid var(--line);font-weight:600}
.tbl td{padding:7px 8px;border-bottom:1px solid #eef1f5}
.tbl .num{text-align:right;font-family:Consolas,monospace}
.mstat{display:flex;align-items:center;gap:14px;padding:12px 14px;border-radius:8px;background:#f6f8fb;border:1px solid var(--line);margin-bottom:12px}
.mstat.on{background:linear-gradient(135deg,#fffaf0,#fdf1d6);border-color:#efd391}
.mstat .ic{font-size:30px}
.mstat b{font-size:17px}
.empty{color:var(--muted);text-align:center;padding:18px;font-size:13px}
@media(max-width:900px){.uc{grid-template-columns:1fr}}