:root{
  /* Light theme inspired by toolsforengineers.com style */
  --bg: #f5f7fb;
  --panel: #ffffff;
  --panel-soft: #f8fafc;
  --border: rgba(15, 23, 42, 0.10);
  --text: #0f172a;
  --muted: #64748b;
  --accent: #2563eb;
  --accent-soft: rgba(37, 99, 235, 0.12);

  --good: #16a34a;
  --good-soft: rgba(22, 163, 74, 0.12);
  --warn: #f59e0b;
  --warn-soft: rgba(245, 158, 11, 0.12);
  --bad: #ef4444;
  --bad-soft: rgba(239, 68, 68, 0.12);

  --shadow: 0 10px 22px rgba(15, 23, 42, 0.06);
  --radius: 16px;

  --sans: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Ubuntu, Cantarell, Noto Sans, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  --mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", "Courier New", monospace;
}

*{ box-sizing: border-box; }
html, body{ height: 100%; }
body{
  margin: 0;
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
}

.container{
  max-width: 1200px;
  margin: 0 auto;
  padding: 18px;
}

/* Top actions (kept minimal for embedding) */
.tool-actions{
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  flex-wrap: wrap;
  margin: 6px 0 12px 0;
}

.btn{
  appearance: none;
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  padding: 10px 12px;
  border-radius: 12px;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, transform 0.06s ease;
  box-shadow: 0 1px 0 rgba(15,23,42,0.04);
}
.btn:hover{
  border-color: rgba(37, 99, 235, 0.35);
  background: rgba(37, 99, 235, 0.04);
}
.btn:active{ transform: translateY(1px); }

/* Notice card */
.notice{
  border: 1px solid rgba(37, 99, 235, 0.22);
  background: rgba(37, 99, 235, 0.06);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-top: 6px;
}
.notice h2{
  margin: 0 0 8px 0;
  font-size: 16px;
}
.notice ul{
  margin: 0;
  padding-left: 18px;
  color: var(--text);
}
.notice li{ margin: 6px 0; }

.tabs{
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  margin-top: 14px;
}

.tab{
  border: 1px solid var(--border);
  background: var(--panel);
  color: rgba(15, 23, 42, 0.85);
  padding: 10px 12px;
  border-radius: 999px;
  cursor: pointer;
  font-size: 13px;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease;
}
.tab:hover{
  border-color: rgba(37, 99, 235, 0.35);
  background: rgba(37, 99, 235, 0.04);
}
.tab.is-active{
  border-color: rgba(37, 99, 235, 0.30);
  background: var(--accent-soft);
  color: var(--accent);
}

.tab-panel{ display: none; margin-top: 14px; }
.tab-panel.is-active{ display: block; }

.grid{ display: grid; gap: 14px; }
.grid-2{ grid-template-columns: 1fr; }
@media (min-width: 980px){
  .grid-2{ grid-template-columns: 1fr 1fr; }
}

.card{
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius);
  padding: 14px 14px;
  box-shadow: var(--shadow);
}
.card h2{
  margin: 0 0 10px 0;
  font-size: 16px;
}
.card h3{
  margin: 18px 0 8px 0;
  font-size: 14px;
}
.muted{ color: var(--muted); }

.field{
  display: grid;
  gap: 6px;
  margin: 10px 0;
}
label{
  font-size: 13px;
  color: rgba(15,23,42,0.78);
}
input, select{
  width: 100%;
  padding: 10px 10px;
  border-radius: 12px;
  border: 1px solid rgba(15, 23, 42, 0.14);
  background: #ffffff;
  color: var(--text);
  outline: none;
  box-shadow: 0 1px 0 rgba(15,23,42,0.03);
}
input::placeholder{ color: rgba(100, 116, 139, 0.8); }
input:focus, select:focus{
  border-color: rgba(37, 99, 235, 0.45);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.help{
  color: var(--muted);
  font-size: 12px;
  line-height: 1.35;
}

.fieldset{
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 14px;
  padding: 10px 12px;
  margin: 12px 0;
  background: var(--panel-soft);
}
.fieldset legend{
  padding: 0 8px;
  color: rgba(15,23,42,0.75);
  font-size: 12px;
}

.results{ display: grid; gap: 10px; }

.result-block{
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 14px;
  padding: 10px 12px;
  background: var(--panel-soft);
}
.result-block h3{
  margin: 0 0 8px 0;
  font-size: 13px;
  color: rgba(15,23,42,0.86);
}

.kv{
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 6px 10px;
  font-size: 13px;
}
.kv div:nth-child(odd){ color: rgba(15,23,42,0.78); }
.kv div:nth-child(even){ color: rgba(15,23,42,0.96); text-align: right; font-variant-numeric: tabular-nums; }

.badge{
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 10px;
  border-radius: 999px;
  border: 1px solid rgba(15, 23, 42, 0.10);
  background: #fff;
  font-size: 12px;
  font-weight: 600;
}
.badge.good{ border-color: rgba(22,163,74,0.25); background: var(--good-soft); color: var(--good); }
.badge.warn{ border-color: rgba(245,158,11,0.25); background: var(--warn-soft); color: var(--warn); }
.badge.bad{ border-color: rgba(239,68,68,0.25); background: var(--bad-soft); color: var(--bad); }

hr.sep{
  border: none;
  border-top: 1px solid rgba(15, 23, 42, 0.10);
  margin: 12px 0;
}

pre{
  background: var(--panel-soft);
  border: 1px solid rgba(15, 23, 42, 0.10);
  border-radius: 14px;
  padding: 12px;
  overflow: auto;
}
pre code{
  font-family: var(--mono);
  font-size: 12px;
  color: rgba(15, 23, 42, 0.92);
}

a{ color: var(--accent); }

@media print{
  .tabs, .tool-actions { display: none !important; }
  body{ background: white; }
  .card, .notice, .result-block { box-shadow: none; }
}


.tip{ margin: 10px 0 0 0; color: var(--muted); font-size: 13px; }
.tip em{ color: rgba(15,23,42,0.86); font-style: normal; }

input:disabled, select:disabled{
  background: #f1f5f9;
  color: rgba(100,116,139,0.9);
  border-color: rgba(15, 23, 42, 0.10);
  cursor: not-allowed;
}