:root{--bg:#ffffff;--text:#111827;--muted:#6b7280;--accent:#0ea5e9;--border:#e5e7eb}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Inter,Arial,sans-serif;line-height:1.6}
.container{max-width:1040px;margin:0 auto;padding:1rem}
.site-header{border-bottom:1px solid var(--border);position:sticky;top:0;background:#fff}
.site-header .brand{font-weight:700;text-decoration:none;color:var(--text);margin-right:1rem}
.site-header nav a{margin-right:1rem;text-decoration:none;color:var(--muted)}
.site-header nav a:hover{color:var(--text)}
h1{font-size:2rem;margin:1rem 0 .5rem}
h2{font-size:1.25rem;margin:1.5rem 0 .5rem}
p{margin:.5rem 0}
ul{padding-left:1.25rem}
.button{display:inline-block;padding:.5rem .75rem;background:var(--accent);color:#fff;text-decoration:none;border-radius:.375rem}
.hardness-bands{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:.25rem}
.source{color:var(--muted);font-size:.9rem}
.comparison-table{width:100%;border-collapse:collapse;margin-top:.5rem}
.comparison-table th,.comparison-table td{border:1px solid var(--border);padding:.5rem;text-align:left}
.comparison-table th{background:#f8fafc}
.assumptions{background:#f9fafb;border:1px solid var(--border);padding:1rem;border-radius:.5rem}
.site-footer{border-top:1px solid var(--border);margin-top:2rem}
.last-verified{color:var(--muted);font-size:.9rem}