/* ============================================================
   企业人工智能应用需求专项调研 · 回执单
   公共样式（表单页 / 后台页 / 扫码页共用）
   ============================================================ */

:root{
  --ink:#0f172a;
  --ink-2:#334155;
  --muted:#64748b;
  --faint:#94a3b8;
  --line:#e5e8ee;
  --line-strong:#cfd6e0;
  --bg:#f1f3f6;
  --card:#ffffff;
  --brand:#123a6b;
  --brand-dark:#0c2a50;
  --brand-2:#1d4ed8;
  --brand-soft:#eef3fb;
  --danger:#b42318;
  --ok:#067647;
  --radius:10px;
  --sans:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;
  --serif:"Songti SC","STSong","Source Han Serif SC","Noto Serif SC",SimSun,serif;
  --mono:ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
}

*{box-sizing:border-box}
html,body{margin:0;padding:0}
body{
  font-family:var(--sans);
  background:var(--bg);
  color:var(--ink);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
  -webkit-text-size-adjust:100%;
}
a{color:var(--brand-2);text-decoration:none}
a:hover{text-decoration:underline}

.wrap{width:100%;max-width:760px;margin:0 auto;padding:0 16px}
.wrap-wide{max-width:1180px}

/* ---------- 顶部 ---------- */
.topbar{background:var(--brand);color:#fff}
.topbar .wrap{
  display:flex;align-items:center;justify-content:space-between;gap:12px;
  height:46px;font-size:12px;letter-spacing:.01em;
}
.topbar-mark{font-weight:500;letter-spacing:.06em}
.topbar-meta{opacity:.72;white-space:nowrap;font-size:11.5px}
.topbar-meta .meta-short{display:none}
@media (max-width:560px){
  .topbar-mark{font-size:11px;letter-spacing:.02em}
  .topbar-meta .meta-full{display:none}
  .topbar-meta .meta-short{display:inline}
}
.topbar a{color:#fff;opacity:.8}
.topbar a:hover{opacity:1;text-decoration:none}

/* ---------- 页头 ---------- */
.doc-head{padding:30px 0 22px;border-bottom:1px solid var(--line)}
.doc-eyebrow{
  display:inline-block;font-size:11px;letter-spacing:.16em;color:var(--brand);
  background:var(--brand-soft);border:1px solid #dbe6f7;border-radius:4px;padding:3px 8px;
}
.doc-head h1{
  font-family:var(--serif);font-size:27px;line-height:1.38;font-weight:600;
  margin:14px 0 12px;letter-spacing:.01em;color:var(--ink);
}
.doc-lead{font-size:13.5px;color:var(--ink-2);margin:0;max-width:62em}
.doc-lead strong{font-weight:600;color:var(--ink)}

@media (max-width:640px){
  .doc-head{padding:24px 0 18px}
  .doc-head h1{font-size:19.5px;line-height:1.45;margin:12px 0 10px}
  .doc-lead{font-size:13px}
}

/* ---------- 卡片 ---------- */
.card{
  background:var(--card);border:1px solid var(--line);border-radius:var(--radius);
  padding:20px;margin-top:14px;
}
.card-h{display:flex;align-items:center;gap:9px;margin:0 0 16px}
.card-h .idx{
  font-family:var(--mono);font-size:11px;line-height:1;color:#fff;background:var(--brand);
  padding:4px 6px;border-radius:4px;letter-spacing:.04em;
}
.card-h h2{font-size:15px;margin:0;font-weight:600;letter-spacing:.01em}
.card-h .hint{margin-left:auto;font-size:11.5px;color:var(--faint);white-space:nowrap}

/* ---------- 字段 ---------- */
.field{margin-bottom:14px}
.field:last-child{margin-bottom:0}
.label{display:block;font-size:13px;color:var(--ink-2);margin-bottom:6px;font-weight:500}
.label .req{color:var(--danger);margin-left:3px}
.label .sub{font-weight:400;color:var(--faint);font-size:11.5px;margin-left:6px}

.input,.select,.textarea{
  width:100%;font-family:inherit;font-size:16px;color:var(--ink);
  background:#fff;border:1px solid var(--line-strong);border-radius:8px;
  padding:9px 12px;outline:none;
  transition:border-color .15s ease,box-shadow .15s ease;
  -webkit-appearance:none;appearance:none;
}
.input::placeholder,.textarea::placeholder{color:#a9b2c0}
.input:focus,.select:focus,.textarea:focus{
  border-color:var(--brand-2);box-shadow:0 0 0 3px rgba(29,78,216,.10);
}
.select{
  padding-right:34px;cursor:pointer;
  background-image:url("data:image/svg+xml;charset=utf-8,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8' viewBox='0 0 12 8'%3E%3Cpath fill='none' stroke='%2364748b' stroke-width='1.6' stroke-linecap='round' stroke-linejoin='round' d='M1 1.5 6 6.5 11 1.5'/%3E%3C/svg%3E");
  background-repeat:no-repeat;background-position:right 12px center;
}
.textarea{resize:vertical;min-height:76px;line-height:1.65}
.input[aria-invalid="true"],.textarea[aria-invalid="true"]{border-color:var(--danger);background:#fffafa}
.err{display:none;font-size:12px;color:var(--danger);margin-top:5px}
.err.on{display:block}

.grid-2{display:grid;grid-template-columns:1fr 1fr;gap:12px}
@media (max-width:460px){.grid-2{gap:10px}}

/* ---------- 说明 / 问题条目 ---------- */
.sec-note{
  font-size:12.5px;color:var(--muted);line-height:1.75;margin:-2px 0 16px;
  padding:10px 12px;background:#f8f9fb;border-left:3px solid var(--line-strong);
  border-radius:0 6px 6px 0;
}
.sec-note strong{color:var(--ink);font-weight:600}
.pm{border:1px solid var(--line);border-radius:8px;background:#fcfcfd;padding:14px 14px 0;margin-bottom:12px}
.pm:last-child{margin-bottom:0}
.pm-h{display:flex;align-items:center;gap:7px;font-size:12.5px;font-weight:600;color:var(--ink-2);margin-bottom:12px}
.pm-no{
  display:inline-flex;align-items:center;justify-content:center;width:18px;height:18px;
  border-radius:4px;background:var(--brand);color:#fff;font-family:var(--mono);font-size:11px;font-weight:400;
}
.sub-inline{font-size:11px;font-weight:400;color:var(--faint);margin-left:2px}
.hint-line{font-size:11.5px;color:var(--faint);margin-top:5px;line-height:1.6}

/* ---------- 多选 chip ---------- */
.chips{display:flex;flex-wrap:wrap;gap:7px}
.chip{position:relative;display:inline-flex;cursor:pointer;-webkit-tap-highlight-color:transparent}
.chip input{position:absolute;opacity:0;width:0;height:0;pointer-events:none}
.chip span{
  display:inline-block;font-size:13px;padding:6px 12px;
  border:1px solid var(--line-strong);border-radius:999px;
  color:var(--ink-2);background:#fff;transition:all .13s ease;white-space:nowrap;
}
.chip input:checked + span{background:var(--brand);border-color:var(--brand);color:#fff}

/* ---------- 单选卡 ---------- */
.opts{display:grid;grid-template-columns:1fr 1fr;gap:8px}
@media (max-width:440px){.opts{grid-template-columns:1fr}}
.opt{
  position:relative;display:block;border:1px solid var(--line-strong);border-radius:8px;
  padding:9px 12px;cursor:pointer;background:#fff;transition:all .13s ease;
  -webkit-tap-highlight-color:transparent;
}
.opt input{position:absolute;opacity:0;width:0;height:0;pointer-events:none}
.opt-t{display:block;font-size:13.5px;font-weight:500;color:var(--ink)}
.opt-d{display:block;font-size:11.5px;color:var(--muted);margin-top:1px;line-height:1.45}
.opt.is-on{border-color:var(--brand);background:var(--brand-soft);box-shadow:inset 0 0 0 1px var(--brand)}
.opt.is-on .opt-t{color:var(--brand)}

/* ---------- 按钮 ---------- */
.btn{
  font-family:inherit;font-size:15px;font-weight:500;line-height:1;
  padding:12px 18px;border-radius:8px;border:1px solid transparent;
  cursor:pointer;transition:background .15s ease,opacity .15s ease;
  -webkit-tap-highlight-color:transparent;
}
.btn-primary{background:var(--brand);color:#fff;width:100%}
.btn-primary:hover{background:var(--brand-dark)}
.btn-primary:disabled{opacity:.55;cursor:not-allowed}
.btn-ghost{background:#fff;border-color:var(--line-strong);color:var(--ink-2);font-size:13.5px;padding:8px 14px}
.btn-ghost:hover{background:#f8f9fb;border-color:var(--faint)}
.btn-sm{font-size:12.5px;padding:6px 11px;border-radius:6px}
.btn-danger{color:var(--danger);border-color:#f0cdc9;background:#fff}
.btn-danger:hover{background:#fff6f5}

/* ---------- 提交区 ---------- */
.submit-bar{padding:20px 0 34px}
.submit-note{
  font-size:11.5px;color:var(--faint);margin:11px 0 0;line-height:1.7;text-align:center;
}
.form-error{
  display:none;font-size:13px;color:var(--danger);background:#fff6f5;
  border:1px solid #f0cdc9;border-radius:8px;padding:10px 12px;margin-bottom:12px;
}
.form-error.on{display:block}

/* ---------- 提交成功 ---------- */
.done{text-align:center;padding:44px 24px}
.done-mark{
  width:52px;height:52px;margin:0 auto 18px;border-radius:50%;
  background:var(--brand-soft);border:1px solid #dbe6f7;
  display:flex;align-items:center;justify-content:center;
}
.done-mark svg{width:24px;height:24px;stroke:var(--brand);fill:none;stroke-width:2.2;stroke-linecap:round;stroke-linejoin:round}
.done h2{font-family:var(--serif);font-size:21px;margin:0 0 8px;font-weight:600}
.done p{font-size:13.5px;color:var(--muted);margin:0 auto;max-width:34em}
.done-meta{
  display:inline-flex;flex-wrap:wrap;gap:8px 20px;margin:20px 0 0;
  font-size:12.5px;color:var(--ink-2);background:#f8f9fb;
  border:1px solid var(--line);border-radius:8px;padding:12px 16px;text-align:left;
}
.done-meta b{font-weight:600;color:var(--ink)}
.done-actions{margin-top:22px;display:flex;gap:10px;justify-content:center;flex-wrap:wrap}

/* ---------- 页脚 ---------- */
.site-foot{
  padding:22px 0 40px;border-top:1px solid var(--line);
  font-size:11.5px;color:var(--faint);display:flex;justify-content:space-between;gap:12px;flex-wrap:wrap;
}

/* ---------- 后台：登录 ---------- */
.login-card{max-width:400px;margin:56px auto;padding:28px}
.login-card h1{font-family:var(--serif);font-size:20px;margin:0 0 6px;font-weight:600}
.login-card p{font-size:12.5px;color:var(--muted);margin:0 0 20px}

/* ---------- 后台：统计 ---------- */
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:14px}
@media (max-width:700px){.stats{grid-template-columns:repeat(2,1fr)}}
.stat{background:#fff;border:1px solid var(--line);border-radius:var(--radius);padding:13px 15px}
.stat-k{font-size:11.5px;color:var(--muted)}
.stat-v{font-family:var(--mono);font-size:22px;font-weight:600;color:var(--brand);line-height:1.35;letter-spacing:-.01em}
.stat-v small{font-size:12px;font-weight:400;color:var(--faint);margin-left:3px}

/* ---------- 后台：工具栏 ---------- */
.toolbar{
  display:flex;gap:8px;align-items:center;flex-wrap:wrap;
  background:#fff;border:1px solid var(--line);border-radius:var(--radius);
  padding:12px;margin-top:14px;
}
.toolbar .input,.toolbar .select{font-size:13.5px;padding:7px 11px;width:auto;min-width:0}
.toolbar .search{flex:1 1 200px;min-width:140px}
.toolbar .select{min-width:118px;padding-right:30px}
.toolbar .spacer{flex:1 1 auto}

/* ---------- 后台：表格 ---------- */
.table-wrap{background:#fff;border:1px solid var(--line);border-radius:var(--radius);margin-top:14px;overflow:hidden}
table{width:100%;border-collapse:collapse;font-size:13px}
thead th{
  text-align:left;font-weight:500;font-size:11.5px;color:var(--muted);letter-spacing:.04em;
  background:#f8f9fb;padding:10px 12px;border-bottom:1px solid var(--line);white-space:nowrap;
}
tbody td{padding:11px 12px;border-bottom:1px solid #f1f3f6;vertical-align:top;color:var(--ink-2)}
tbody tr:last-child td{border-bottom:none}
tbody tr:hover{background:#fbfcfd}
td.name{color:var(--ink);font-weight:500}
td.nowrap{white-space:nowrap}
td.time{font-family:var(--mono);font-size:11.5px;color:var(--faint);white-space:nowrap}
.sub-line{display:block;color:var(--faint);font-size:11px;line-height:1.6;font-weight:400;white-space:nowrap}
.empty{padding:52px 16px;text-align:center;color:var(--faint);font-size:13px}

.tag{
  display:inline-block;font-size:11px;padding:2px 7px;border-radius:4px;
  background:#f1f3f6;color:var(--ink-2);white-space:nowrap;
}
.tag-ok{background:#e9f7f0;color:var(--ok)}
.tag-warn{background:#fef5e7;color:#b25e09}
.tag-mute{background:#f1f3f6;color:var(--muted)}

@media (max-width:820px){
  .table-wrap{border:none;background:transparent;overflow:visible}
  table,tbody,tr,td{display:block;width:100%}
  thead{display:none}
  tbody tr{
    background:#fff;border:1px solid var(--line);border-radius:var(--radius);
    margin-bottom:10px;padding:6px 14px;
  }
  tbody tr:hover{background:#fff}
  tbody td{border-bottom:1px dashed #eef0f4;padding:7px 0;font-size:13px}
  tbody tr td:last-child{border-bottom:none}
  tbody td[data-label]::before{
    content:attr(data-label);display:inline-block;min-width:76px;
    font-size:11.5px;color:var(--faint);margin-right:8px;
  }
  tbody td.hide-sm{display:none}
}

/* ---------- 弹窗 ---------- */
.modal-mask{
  position:fixed;inset:0;background:rgba(15,23,42,.42);
  display:none;align-items:flex-start;justify-content:center;
  padding:40px 16px;z-index:50;overflow:auto;
}
.modal-mask.on{display:flex}
.modal{
  background:#fff;border-radius:12px;width:100%;max-width:630px;
  box-shadow:0 16px 48px rgba(15,23,42,.18);overflow:hidden;
}
.modal-h{
  display:flex;align-items:center;gap:12px;padding:16px 20px;border-bottom:1px solid var(--line);
}
.modal-h h3{margin:0;font-size:15px;font-weight:600}
.modal-h .close{
  margin-left:auto;border:none;background:transparent;font-size:20px;line-height:1;
  color:var(--faint);cursor:pointer;padding:4px 6px;border-radius:6px;
}
.modal-h .close:hover{background:#f1f3f6;color:var(--ink)}
.modal-b{padding:18px 20px;max-height:66vh;overflow:auto}
.modal-f{padding:12px 20px;border-top:1px solid var(--line);display:flex;gap:8px;justify-content:flex-end;background:#fafbfc}

.dl{display:grid;grid-template-columns:124px 1fr;gap:9px 14px;font-size:13px}
.dl dt{color:var(--faint);font-size:12.5px}
.dl dd{margin:0;color:var(--ink);word-break:break-word}

/* ---------- 扫码页 ---------- */
.poster{
  background:#fff;border:1px solid var(--line);border-radius:12px;
  max-width:420px;margin:32px auto;padding:34px 30px;text-align:center;
}
.poster-eyebrow{font-size:11px;letter-spacing:.18em;color:var(--faint)}
.poster h1{font-family:var(--serif);font-size:21px;line-height:1.45;margin:12px 0 6px;font-weight:600}
.poster p.sub{font-size:12.5px;color:var(--muted);margin:0 0 22px;line-height:1.7}
.qr-box{
  display:inline-block;padding:14px;border:1px solid var(--line);border-radius:10px;background:#fff;
  min-width:220px;min-height:220px;
}
.qr-box canvas,.qr-box img{display:block;width:200px;height:200px}
.qr-tip{font-size:12px;color:var(--ink-2);margin:18px 0 0;font-weight:500}
.poster .url{
  font-family:var(--mono);font-size:10.5px;color:var(--faint);
  word-break:break-all;margin:10px 0 0;line-height:1.6;
}
.poster-line{height:1px;background:var(--line);margin:20px 0}
.poster-foot{font-size:11.5px;color:var(--faint);line-height:1.8}

@media print{
  body{background:#fff}
  .topbar,.no-print,.site-foot{display:none!important}
  .poster{border:none;box-shadow:none;margin:0 auto;padding:20px;max-width:none}
  .card{border:none}
}