/* engineeringtools.org - one stylesheet, no external fonts or scripts */
:root{--ink:#1d2733;--muted:#5b6775;--line:#dde3ea;--bg:#f5f7fa;--card:#fff;--brand:#0b5394;--brand2:#073763;--ok:#1f7a3a;--err:#b3261e}
*{box-sizing:border-box}
html{font-size:16px}
body{margin:0;font-family:system-ui,-apple-system,"Segoe UI",Roboto,Arial,sans-serif;color:var(--ink);background:var(--bg);line-height:1.55}
a{color:var(--brand)}a:hover{color:var(--brand2)}
.site-header{background:#fff;border-bottom:1px solid var(--line)}
.site-header .wrap{display:flex;align-items:center;gap:24px;flex-wrap:wrap;padding:10px 20px}
.brand img{height:56px;width:auto;display:block}
.nav{display:flex;flex-wrap:wrap;gap:4px 2px;margin:0;padding:0;list-style:none}
.nav a{display:block;padding:6px 10px;border-radius:6px;text-decoration:none;color:var(--ink);font-size:.95rem}
.nav a:hover,.nav a.active{background:var(--bg);color:var(--brand)}
.wrap{max-width:1180px;margin:0 auto}
main.wrap{padding:24px 20px 40px}
.card{background:var(--card);border:1px solid var(--line);border-radius:10px;padding:24px 28px}
h1{font-size:1.8rem;margin:0 0 16px;line-height:1.25}
h2{font-size:1.35rem;margin:28px 0 10px}
.content img{max-width:100%!important;height:auto!important}
.content table{max-width:100%!important;border-collapse:collapse}
.content table[style*="width"],.content table[width]{width:100%!important}
.content td,.content th{max-width:100%}
.content td[style*="width"]{width:auto!important}
.content iframe{max-width:100%}
.content pre,.content code{background:#f0f3f6;border-radius:4px}
.content pre{padding:10px;overflow:auto}
.btn,.btn-primary,button.btn{display:inline-block;background:var(--brand);color:#fff!important;border:0;border-radius:6px;padding:9px 18px;font-size:1rem;text-decoration:none;cursor:pointer}
.btn:hover{background:var(--brand2)}
.small{font-size:.88rem;color:var(--muted)}
.site-footer{border-top:1px solid var(--line);background:#fff}
.site-footer .wrap{padding:16px 20px;text-align:center;font-size:.9rem;color:var(--muted)}
/* help index */
.help-search{width:100%;max-width:520px;padding:9px 12px;border:1px solid var(--line);border-radius:6px;font-size:1rem;margin:6px 0 14px}
.help-list{columns:2 340px;padding:0;margin:0;list-style:none}
.help-list li{break-inside:avoid;padding:3px 0}
.help-list .ids{color:var(--muted);font-size:.82rem;margin-left:6px}
/* forms */
form.et-form{max-width:640px}
.et-form label{display:block;font-weight:600;margin:14px 0 4px}
.et-form input[type=text],.et-form input[type=email],.et-form select,.et-form textarea{width:100%;padding:8px 10px;border:1px solid #c5ced8;border-radius:6px;font:inherit;background:#fff}
.et-form textarea{min-height:90px}
.et-form .opts{display:flex;flex-wrap:wrap;gap:4px 18px;font-weight:400}
.et-form .opts label{font-weight:400;margin:0;display:flex;gap:6px;align-items:center}
.et-form .hp{position:absolute;left:-5000px}
.et-form .req{color:var(--err)}
.et-form .actions{margin-top:18px}
.notice{padding:12px 16px;border-radius:8px;background:#eef6ee;border:1px solid #cfe6d2}
.notice.err{background:#fbeeee;border-color:#efcdcb}
@media (max-width:700px){.card{padding:18px}.brand img{height:44px}h1{font-size:1.5rem}}