/* ======================================================================
   位运算计算器 · 独立设计（荧光绿二进制实验台主题）
   ====================================================================== */
.bw{
  --ink:#14251c; --sub:#5c7468; --faint:#8ba79a;
  --bg:#f2f7f3; --card:#ffffff; --card2:#e8f1ea; --line:#cfe0d4; --line2:#ddebe1;
  --pri:#15803d; --pri-2:#22c55e; --pri-soft:#dcf5e3; --pri-ink:#14532d;
  --bit1:#16a34a; --bit0:#d7e5db; --res:#f59e0b;
  --red:#b42323; --red-soft:#fdecec;
  --r:12px;
  --shadow:0 1px 2px rgba(20,37,28,.05),0 12px 30px rgba(21,128,61,.08);
  color:var(--ink);
  font-family:-apple-system,"PingFang SC","HarmonyOS Sans SC","Microsoft YaHei",system-ui,sans-serif;
  font-size:15px; line-height:1.75;
  background:
    repeating-linear-gradient(0deg,transparent 0 27px,rgba(21,128,61,.045) 27px 28px),
    repeating-linear-gradient(90deg,transparent 0 27px,rgba(21,128,61,.045) 27px 28px),
    var(--bg);
  padding:0 16px 56px;
}
:root[data-theme="dark"] .bw{
  --ink:#dcf5e3; --sub:#8fbfa2; --faint:#5e8a70;
  --bg:#0a120d; --card:#101b14; --card2:#15241b; --line:#24402e; --line2:#1c3325;
  --pri:#4ade80; --pri-2:#86efac; --pri-soft:rgba(74,222,128,.12); --pri-ink:#bbf7d0;
  --bit1:#22c55e; --bit0:#1a2b20; --res:#fbbf24;
  --red:#f87171; --red-soft:rgba(248,113,113,.12);
  --shadow:0 1px 2px rgba(0,0,0,.5),0 14px 32px rgba(0,0,0,.5);
}
.bw *{box-sizing:border-box;}
.bw-wrap{max-width:1140px;margin:0 auto;}
.bw input,.bw select,.bw .bw-mono{font-family:"JetBrains Mono",ui-monospace,Consolas,monospace;}

.bw-hero{margin-top:22px;background:linear-gradient(135deg,#052e16,#14532d 60%,#166534);color:#dcfce7;
  border-radius:var(--r);padding:24px 28px;box-shadow:var(--shadow);position:relative;overflow:hidden;}
:root[data-theme="dark"] .bw-hero{background:linear-gradient(135deg,#04150b,#0b2e1a 60%,#123c22);}
.bw-hero::before{content:"01001010 01001110 01010010 01000100 01001111 01010010";position:absolute;right:-10px;top:8px;
  font-family:ui-monospace,Consolas,monospace;font-size:11px;letter-spacing:.2em;opacity:.25;white-space:nowrap;}
.bw-hero h1{margin:0 0 8px;font-size:clamp(24px,3.6vw,32px);font-weight:900;}
.bw-hero p{margin:0;color:#a7d8b8;font-size:14.5px;max-width:800px;}
.bw-hero p em{font-style:normal;color:#fef08a;font-weight:800;}

.bw-desk{display:grid;grid-template-columns:380px 1fr;gap:18px;margin-top:20px;}
@media (max-width:960px){.bw-desk{grid-template-columns:1fr;}}
.bw-card{background:var(--card);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow);padding:18px;}
.bw-card h2{margin:0 0 12px;font-size:15.5px;font-weight:900;display:flex;align-items:center;gap:8px;letter-spacing:.03em;}
.bw-card h2::before{content:"▸";color:var(--pri);}
.bw-field{margin-bottom:12px;}
.bw-field label{display:block;font-size:12.5px;font-weight:800;color:var(--sub);margin-bottom:4px;letter-spacing:.05em;}
.bw-field input,.bw-field select{width:100%;padding:9px 12px;border-radius:8px;border:1.5px solid var(--line);
  background:var(--card2);color:var(--ink);font-size:14px;outline:none;}
.bw-field input:focus,.bw-field select:focus{border-color:var(--pri-2);box-shadow:0 0 0 3px var(--pri-soft);}
.bw-2col{display:grid;grid-template-columns:1fr 1fr;gap:10px;}
.bw-ops{display:grid;grid-template-columns:repeat(4,1fr);gap:6px;margin-bottom:12px;}
.bw-op{border:1.5px solid var(--line);background:var(--card2);color:var(--sub);border-radius:8px;padding:8px 4px;
  font-size:13px;font-weight:800;cursor:pointer;font-family:ui-monospace,Consolas,monospace;transition:all .12s;}
.bw-op:hover{border-color:var(--pri-2);}
.bw-op.on{background:var(--pri);border-color:var(--pri);color:#fff;}
:root[data-theme="dark"] .bw-op.on{color:#06170c;}
.bw-row{display:flex;gap:8px;flex-wrap:wrap;margin-top:6px;}
.bw-btn{border:none;border-radius:9px;padding:9px 18px;font-size:14px;font-weight:800;cursor:pointer;transition:all .12s;}
.bw-btn-go{background:var(--pri);color:#fff;}
:root[data-theme="dark"] .bw-btn-go{color:#06170c;}
.bw-btn-go:hover{background:var(--pri-2);}
.bw-btn-ghost{background:var(--card2);color:var(--pri-ink);border:1.5px solid var(--line);}
.bw-btn-ghost:hover{border-color:var(--pri-2);}
.bw-msg{margin-top:10px;font-size:13px;min-height:20px;font-weight:700;}
.bw-msg.err{color:var(--red);}
.bw-msg.ok{color:var(--pri);}

.bw-grid{overflow-x:auto;padding-bottom:4px;}
.bw-rowbits{display:flex;align-items:center;gap:6px;margin-bottom:6px;}
.bw-rowlab{width:64px;flex:none;font-size:12.5px;font-weight:900;color:var(--sub);font-family:ui-monospace,Consolas,monospace;text-align:right;}
.bw-cells{display:flex;gap:3px;}
.bw-cells .bw-sep{width:8px;}
.bw-cell{width:22px;height:26px;flex:none;border-radius:4px;display:flex;align-items:center;justify-content:center;
  font-family:ui-monospace,Consolas,monospace;font-size:12px;font-weight:800;background:var(--bit0);color:var(--faint);}
.bw-cell.one{background:var(--bit1);color:#fff;}
:root[data-theme="dark"] .bw-cell.one{color:#06170c;}
.bw-cell.res{outline:2px solid var(--res);outline-offset:1px;}
.bw-idx{display:flex;gap:3px;margin:0 0 8px;}
.bw-idx .bw-sep{width:8px;}
.bw-idx span{width:22px;flex:none;text-align:center;font-size:9.5px;color:var(--faint);font-family:ui-monospace,Consolas,monospace;}
.bw-eq{font-size:26px;font-weight:900;color:var(--pri-ink);font-family:ui-monospace,Consolas,monospace;margin:6px 0 10px;text-align:center;}

.bw-res{display:grid;grid-template-columns:repeat(auto-fit,minmax(210px,1fr));gap:10px;margin-top:14px;}
.bw-res div{background:var(--card2);border:1px solid var(--line2);border-radius:9px;padding:9px 12px;}
.bw-res span{display:block;font-size:11.5px;font-weight:800;color:var(--sub);letter-spacing:.06em;}
.bw-res b{font-size:15px;font-family:ui-monospace,Consolas,monospace;color:var(--pri-ink);word-break:break-all;}

.bw-faq{margin-top:34px;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:22px 24px;box-shadow:var(--shadow);}
.bw-faq h2{margin:0 0 12px;font-size:19px;font-weight:900;}
.bw-faq h3{margin:18px 0 6px;font-size:15.5px;font-weight:800;color:var(--pri-ink);}
.bw-faq p{margin:0;color:var(--sub);font-size:14px;}
.bw-faq p b{color:var(--ink);}

/* ===== 新增：方案对比 / 移位扫描（前缀 bwx） ===== */
.bwx-lab{margin-top:20px;background:var(--card);border:1px solid var(--line);border-radius:var(--r);
  box-shadow:var(--shadow);padding:18px 20px;}
.bwx-lab h2{margin:0 0 8px;font-size:15.5px;font-weight:900;display:flex;align-items:center;gap:8px;letter-spacing:.03em;}
.bwx-lab h2::before{content:"▸";color:var(--pri);}
.bwx-head{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:8px;}
.bwx-head h2{margin:0;}
.bwx-actions{display:flex;gap:8px;flex-wrap:wrap;}
.bwx-lab > p{margin:0 0 10px;color:var(--sub);font-size:13.5px;}
.bwx-lab > p b{color:var(--pri-ink);}
.bwx-tblwrap{overflow-x:auto;}
.bwx-tbl{width:100%;min-width:600px;border-collapse:collapse;font-size:12.5px;
  font-family:"JetBrains Mono",ui-monospace,Consolas,monospace;}
.bwx-tbl th{text-align:left;color:var(--faint);font-size:11.5px;font-weight:800;letter-spacing:.04em;
  padding:6px 10px;border-bottom:1px solid var(--line);white-space:nowrap;}
.bwx-tbl td{padding:7px 10px;border-bottom:1px solid var(--line2);word-break:break-all;}
.bwx-tbl tr.cur{background:var(--pri-soft);}
.bwx-tbl tr.cur td:first-child{color:var(--pri-ink);font-weight:800;}
.bwx-d{font-weight:800;color:var(--res);}
.bwx-d.zero{color:var(--faint);}
.bwx-empty{padding:16px;text-align:center;color:var(--faint);font-size:13px;
  border:1px dashed var(--line);border-radius:var(--r);background:var(--card2);}
.bwx-svgwrap{margin-top:10px;overflow-x:auto;border:1px solid var(--line2);
  border-radius:var(--r);background:var(--card2);padding:8px;}
.bwx-svgwrap svg{display:block;width:100%;min-width:640px;height:auto;}
.bwx-facts{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px;}
.bwx-facts span{background:var(--card2);border:1px solid var(--line2);border-radius:999px;
  padding:4px 12px;font-size:12px;color:var(--sub);}
.bwx-facts b{color:var(--pri-ink);font-family:ui-monospace,Consolas,monospace;}
@media (max-width:640px){
  .bwx-lab{padding:14px;}
  .bwx-head{flex-direction:column;align-items:flex-start;}
}