/* style.css - Online Tip Calculator | Shared Stylesheet */
*,*::before,*::after{box-sizing:border-box}
*{margin:0}
html{scroll-behavior:smooth}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation-duration:.01ms !important;transition-duration:.01ms !important}}
:root{
  --bg:#ffffff;
  --surface:#f8fafc;
  --surface-2:#f1f5f9;
  --text:#0f172a;
  --muted:#475569;
  --border:#e2e8f0;
  --border-strong:#cbd5e1;
  --primary:#0f766e;
  --primary-hover:#115e59;
  --primary-soft:#ccfbf1;
  --focus:#0f766e;
  --radius:12px;
  --radius-sm:8px;
  --max:1100px;
  --header-h:64px;
  --shadow:0 1px 3px rgba(15,23,42,.08),0 1px 2px rgba(15,23,42,.08);
}
@media(prefers-color-scheme:dark){
  :root{
    --bg:#0f172a;
    --surface:#1e293b;
    --surface-2:#1e293b;
    --text:#f1f5f9;
    --muted:#94a3b8;
    --border:#334155;
    --border-strong:#475569;
    --primary:#2dd4bf;
    --primary-hover:#5eead4;
    --primary-soft:#134e4a;
  }
}
body{
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif,"Apple Color Emoji","Segoe UI Emoji";
  background:var(--bg);
  color:var(--text);
  line-height:1.65;
  font-size:17px;
  -webkit-font-smoothing:antialiased;
}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible{outline:2px solid var(--focus);outline-offset:2px}
img,svg{display:block;max-width:100%}
.skip-link{
  position:absolute;left:-9999px;top:auto;width:1px;height:1px;overflow:hidden;
}
.skip-link:focus{left:16px;top:12px;width:auto;height:auto;padding:10px 16px;background:var(--text);color:var(--bg);border-radius:8px;z-index:999}
.container{max-width:var(--max);margin:0 auto;padding:0 20px}
header.site-header{
  position:sticky;top:0;z-index:40;
  background:var(--bg);border-bottom:1px solid var(--border);
}
.header-inner{display:flex;align-items:center;justify-content:space-between;min-height:var(--header-h);gap:16px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;font-size:18px;color:var(--text);letter-spacing:-.02em}
.brand svg{width:32px;height:32px;flex:0 0 32px}
.brand span{white-space:nowrap}
nav.primary-nav ul{display:flex;list-style:none;gap:4px;flex-wrap:wrap;padding:0}
nav.primary-nav a{display:inline-flex;align-items:center;min-height:44px;padding:0 12px;border-radius:8px;color:var(--muted);font-size:15px;font-weight:500}
nav.primary-nav a:hover{background:var(--surface);color:var(--text);text-decoration:none}
nav.primary-nav a[aria-current="page"]{background:var(--surface-2);color:var(--text)}
.menu-toggle{display:none;min-height:44px;min-width:44px;border:1px solid var(--border);background:var(--bg);border-radius:8px;padding:0 12px;font:inherit;font-weight:600;cursor:pointer}
@media(max-width:760px){
  nav.primary-nav{display:none;width:100%}
  nav.primary-nav.is-open{display:block}
  nav.primary-nav ul{flex-direction:column;padding:10px 0 16px}
  nav.primary-nav a{width:100%}
  .header-inner{flex-wrap:wrap}
  .menu-toggle{display:inline-flex;align-items:center;justify-content:center}
}
main{padding:32px 0 48px}
.hero{padding:8px 0 24px}
h1{font-size:clamp(28px,4vw,40px);line-height:1.15;letter-spacing:-.03em;margin-bottom:12px}
h1 + .lead{color:var(--muted);font-size:18px;max-width:65ch}
h2{font-size:24px;letter-spacing:-.02em;margin:36px 0 12px;line-height:1.3}
h3{font-size:18px;margin:20px 0 8px}
p{margin:0 0 14px;max-width:70ch}
ul,ol{margin:0 0 14px 20px;max-width:70ch}
li{margin:4px 0}
.card{
  background:var(--bg);border:1px solid var(--border);border-radius:var(--radius);
  box-shadow:var(--shadow);padding:20px;
}
.tool-wrap{display:grid;gap:24px}
@media(min-width:900px){.tool-wrap{grid-template-columns:1.15fr .85fr;align-items:start}}
.tool-card{padding:24px}
.tool-grid{display:grid;gap:16px}
.field{display:grid;gap:6px}
.field label{font-size:14px;font-weight:600}
.field input,.field select{
  width:100%;min-height:44px;padding:10px 12px;
  border:1px solid var(--border-strong);border-radius:var(--radius-sm);
  background:var(--bg);color:var(--text);font:inherit;font-size:16px;
}
.field input:focus,.field select:focus{border-color:var(--primary)}
.help{font-size:13px;color:var(--muted)}
.presets{display:flex;flex-wrap:wrap;gap:8px}
.preset-btn{
  min-height:44px;min-width:56px;padding:0 14px;
  border:1px solid var(--border-strong);background:var(--bg);color:var(--text);
  border-radius:999px;font:inherit;font-size:14px;font-weight:600;cursor:pointer;
}
.preset-btn:hover{border-color:var(--text)}
.preset-btn.is-active{background:var(--text);color:var(--bg);border-color:var(--text)}
@media(prefers-color-scheme:dark){.preset-btn.is-active{background:var(--primary);color:#04201e;border-color:var(--primary)}}
.inline{display:flex;gap:12px;align-items:center;flex-wrap:wrap}
.toggle{display:inline-flex;align-items:center;gap:10px;cursor:pointer;min-height:44px}
.toggle input{width:18px;height:18px;accent-color:var(--primary)}
.results{
  background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px;display:grid;gap:14px;
}
.results h2{margin:0;font-size:18px}
.result-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.result-box{background:var(--bg);border:1px solid var(--border);border-radius:var(--radius-sm);padding:14px}
.result-box strong{display:block;font-size:12px;letter-spacing:.06em;text-transform:uppercase;color:var(--muted);margin-bottom:4px}
.result-box span{font-size:22px;font-weight:700;letter-spacing:-.02em}
.result-box.total{grid-column:1 / -1}
.actions{display:flex;gap:10px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;justify-content:center;min-height:44px;
  padding:0 18px;border-radius:999px;border:1px solid var(--border-strong);
  background:var(--bg);color:var(--text);font:inherit;font-size:15px;font-weight:600;cursor:pointer;text-decoration:none;
}
.btn:hover{text-decoration:none;filter:brightness(.98)}
.btn-primary{background:var(--primary);border-color:var(--primary);color:#fff}
.btn-primary:hover{background:var(--primary-hover);border-color:var(--primary-hover)}
@media(prefers-color-scheme:dark){.btn-primary{color:#04201e}}
.prose{max-width:75ch}
.table-wrap{overflow-x:auto;border:1px solid var(--border);border-radius:var(--radius-sm)}
table{width:100%;border-collapse:collapse;font-size:15px;min-width:520px}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--border)}
th{background:var(--surface);font-size:13px;letter-spacing:.04em;text-transform:uppercase;color:var(--muted)}
.faq{border-top:1px solid var(--border);margin-top:12px}
.faq details{border-bottom:1px solid var(--border);padding:14px 0}
.faq summary{font-weight:600;cursor:pointer;list-style:none}
.faq summary::-webkit-details-marker{display:none}
.faq p{margin:8px 0 0}
.breadcrumbs{font-size:13px;color:var(--muted);margin-bottom:16px}
.breadcrumbs a{color:var(--muted)}
.breadcrumbs ol{list-style:none;display:flex;gap:6px;flex-wrap:wrap;margin:0;padding:0}
.breadcrumbs li+li::before{content:"/";margin-right:6px;color:var(--border-strong)}
.notice{background:var(--primary-soft);border:1px solid var(--border);border-radius:var(--radius-sm);padding:12px 14px;font-size:14px}
footer.site-footer{border-top:1px solid var(--border);padding:28px 0;color:var(--muted);font-size:14px}
.footer-grid{display:grid;gap:20px}
@media(min-width:700px){.footer-grid{grid-template-columns:1.2fr .8fr}}
.footer-links{display:flex;flex-wrap:wrap;gap:8px 16px;list-style:none;padding:0;margin:0}
.footer-links a{color:var(--muted);min-height:44px;display:inline-flex;align-items:center}
.muted{color:var(--muted)}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.error{color:#b91c1c;font-size:13px;min-height:1.2em}
@media(prefers-color-scheme:dark){.error{color:#fca5a5}}