/* Idiot Fitness Calculators Tools — core stylesheet */
:root{
  --bg:#f8fafc;
  --surface:#ffffff;
  --surface-2:#f1f5f9;
  --text:#0f172a;
  --text-muted:#475569;
  --text-faint:#94a3b8;
  --border:#e2e8f0;
  --primary:#4f46e5;
  --primary-dark:#4338ca;
  --primary-light:#eef2ff;
  --accent:#0ea5e9;
  --success:#059669;
  --radius:12px;
  --radius-sm:8px;
  --shadow-sm:0 1px 2px rgba(15,23,42,.06);
  --shadow-md:0 4px 16px rgba(15,23,42,.08);
  --shadow-lg:0 12px 32px rgba(15,23,42,.12);
  --max-w:1180px;
  --font-body:'Inter',system-ui,-apple-system,Segoe UI,Roboto,sans-serif;
  --font-display:'Sora',var(--font-body);
}
*,*::before,*::after{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:var(--font-body);
  background:var(--bg);
  color:var(--text);
  line-height:1.6;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;display:block}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3,h4{font-family:var(--font-display);line-height:1.2;margin:0 0 .5em;letter-spacing:-.01em}
p{margin:0 0 1em}
.container{max-width:var(--max-w);margin:0 auto;padding:0 20px}
:focus-visible{outline:2px solid var(--primary);outline-offset:2px}

/* ===== Header ===== */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.92);
  backdrop-filter:blur(8px);
  border-bottom:1px solid var(--border);
}
.header-inner{
  display:flex;align-items:center;justify-content:space-between;
  padding:14px 20px;max-width:var(--max-w);margin:0 auto;gap:20px;
}
.brand{display:flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:700;font-size:1.15rem;color:var(--text)}
.brand:hover{text-decoration:none}
.brand-mark{
  width:34px;height:34px;border-radius:9px;
  background:linear-gradient(135deg,var(--primary),var(--accent));
  display:flex;align-items:center;justify-content:center;color:#fff;font-weight:800;font-size:.95rem;
  box-shadow:var(--shadow-sm);
}
.main-nav{display:flex;align-items:center;gap:22px}
.main-nav a{color:var(--text-muted);font-weight:500;font-size:.95rem}
.main-nav a:hover{color:var(--primary);text-decoration:none}

.search-wrap{position:relative;width:260px}
.search-input{
  width:100%;padding:9px 14px 9px 36px;border-radius:999px;border:1px solid var(--border);
  background:var(--surface-2);font-size:.9rem;color:var(--text);
}
.search-input:focus{background:#fff;border-color:var(--primary)}
.search-icon{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--text-faint);font-size:.9rem}
.search-results{
  position:absolute;top:calc(100% + 8px);left:0;right:0;
  background:#fff;border:1px solid var(--border);border-radius:var(--radius-sm);
  box-shadow:var(--shadow-lg);max-height:320px;overflow-y:auto;display:none;z-index:80;
}
.search-results.active{display:block}
.search-results a{display:block;padding:10px 14px;color:var(--text);font-size:.9rem;border-bottom:1px solid var(--border)}
.search-results a:last-child{border-bottom:none}
.search-results a:hover{background:var(--primary-light);text-decoration:none}
.search-empty{padding:12px 14px;color:var(--text-faint);font-size:.88rem}

.nav-toggle{display:none;background:none;border:1px solid var(--border);border-radius:8px;padding:8px 10px;font-size:1.1rem;cursor:pointer}

/* ===== Hero ===== */
.hero{
  padding:64px 0 56px;
  background:
    radial-gradient(circle at 10% 20%,rgba(79,70,229,.08),transparent 45%),
    radial-gradient(circle at 90% 10%,rgba(14,165,233,.08),transparent 40%),
    var(--bg);
  border-bottom:1px solid var(--border);
}
.hero .eyebrow{
  display:inline-block;font-size:.78rem;font-weight:700;letter-spacing:.06em;text-transform:uppercase;
  color:var(--primary);background:var(--primary-light);padding:5px 12px;border-radius:999px;margin-bottom:16px;
}
.hero h1{font-size:clamp(1.9rem,4vw,3rem);max-width:820px}
.hero p.lead{font-size:1.1rem;color:var(--text-muted);max-width:640px}
.hero-stats{display:flex;gap:28px;margin-top:28px;flex-wrap:wrap}
.hero-stat b{display:block;font-family:var(--font-display);font-size:1.5rem;color:var(--text)}
.hero-stat span{font-size:.85rem;color:var(--text-muted)}

/* ===== Category grid ===== */
.section{padding:52px 0}
.section-head{display:flex;align-items:flex-end;justify-content:space-between;margin-bottom:26px;gap:16px;flex-wrap:wrap}
.section-head h2{font-size:1.6rem}
.section-head p{color:var(--text-muted);margin:0}

.tool-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:18px}
.tool-card{
  background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:20px;transition:transform .15s ease,box-shadow .15s ease,border-color .15s ease;
  display:flex;flex-direction:column;gap:10px;
}
.tool-card:hover{transform:translateY(-3px);box-shadow:var(--shadow-md);border-color:#c7d2fe;text-decoration:none}
.tool-icon{
  width:42px;height:42px;border-radius:10px;background:var(--primary-light);color:var(--primary);
  display:flex;align-items:center;justify-content:center;font-size:1.2rem;
}
.tool-card h3{font-size:1.02rem;color:var(--text);margin:0}
.tool-card p{font-size:.87rem;color:var(--text-muted);margin:0}
.tool-card .go{font-size:.82rem;font-weight:600;color:var(--primary);margin-top:auto}

/* ===== Tool page layout ===== */
.tool-page-header{padding:36px 0 28px;border-bottom:1px solid var(--border);background:var(--surface)}
.breadcrumbs{font-size:.85rem;color:var(--text-faint);margin-bottom:12px}
.breadcrumbs a{color:var(--text-muted)}
.tool-page-header h1{font-size:clamp(1.6rem,3vw,2.2rem)}
.tool-page-header .lead{color:var(--text-muted);max-width:700px;margin-bottom:0}

.tool-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:28px;align-items:start;padding:36px 0}
.calc-card{
  background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:26px;box-shadow:var(--shadow-sm);
}
.field-row{display:grid;grid-template-columns:1fr 1fr;gap:14px;margin-bottom:14px}
.field{display:flex;flex-direction:column;gap:6px}
.field label{font-size:.85rem;font-weight:600;color:var(--text)}
.field input,.field select{
  padding:10px 12px;border:1px solid var(--border);border-radius:var(--radius-sm);font-size:.95rem;
  background:#fff;color:var(--text);font-family:var(--font-body);width:100%;
}
.field input:focus,.field select:focus{border-color:var(--primary)}
.field .hint{font-size:.78rem;color:var(--text-faint)}
.unit-toggle{display:inline-flex;border:1px solid var(--border);border-radius:999px;overflow:hidden;margin-bottom:16px}
.unit-toggle button{
  border:none;background:#fff;padding:7px 16px;font-size:.85rem;cursor:pointer;color:var(--text-muted);font-weight:600;
}
.unit-toggle button.active{background:var(--primary);color:#fff}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  background:var(--primary);color:#fff;border:none;padding:12px 22px;border-radius:var(--radius-sm);
  font-weight:600;font-size:.95rem;cursor:pointer;transition:background .15s ease;
}
.btn:hover{background:var(--primary-dark);text-decoration:none;color:#fff}
.btn.secondary{background:transparent;border:1px solid var(--border);color:var(--text)}
.btn.secondary:hover{background:var(--surface-2)}
.result-box{
  margin-top:20px;padding:20px;border-radius:var(--radius-sm);background:var(--primary-light);
  border:1px solid #c7d2fe;display:none;
}
.result-box.active{display:block}
.result-box .big{font-family:var(--font-display);font-size:2rem;color:var(--primary-dark);font-weight:700}
.result-box .label{font-size:.85rem;color:var(--text-muted);margin-bottom:4px}
.result-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:14px;margin-top:14px}
.result-grid .item{background:#fff;border-radius:var(--radius-sm);padding:12px 14px;border:1px solid var(--border)}
.result-grid .item .v{font-weight:700;font-family:var(--font-display);font-size:1.15rem}
.result-grid .item .k{font-size:.78rem;color:var(--text-muted)}
.error-text{color:#dc2626;font-size:.85rem;margin-top:10px;display:none}
.error-text.active{display:block}

.sidebar .box{
  background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);
  padding:18px;margin-bottom:18px;
}
.sidebar h4{font-size:.95rem;margin-bottom:10px}
.sidebar ul{list-style:none;margin:0;padding:0}
.sidebar li{margin-bottom:8px}
.sidebar a{font-size:.88rem;color:var(--text-muted)}
.sidebar a:hover{color:var(--primary)}

.article{padding:16px 0 8px;max-width:820px}
.article h2{font-size:1.35rem;margin-top:2em}
.article h2:first-child{margin-top:0}
.article p{color:var(--text-muted)}
.faq-item{border-bottom:1px solid var(--border);padding:16px 0}
.faq-item h3{font-size:1rem;margin-bottom:6px;color:var(--text)}
.faq-item p{margin:0;color:var(--text-muted);font-size:.94rem}

/* ===== Static pages ===== */
.static-page{padding:48px 0;max-width:820px}
.static-page h1{margin-bottom:.3em}
.static-page h2{font-size:1.25rem;margin-top:1.8em}
.static-page p,.static-page li{color:var(--text-muted)}

/* ===== Footer ===== */
.site-footer{background:#0f172a;color:#cbd5e1;margin-top:40px}
.footer-grid{
  display:grid;grid-template-columns:1.4fr 1fr 1fr 1fr;gap:32px;
  padding:48px 0 28px;max-width:var(--max-w);margin:0 auto;padding-left:20px;padding-right:20px;
}
.footer-grid.footer-grid-3{grid-template-columns:1.4fr 1fr 1fr}
.footer-grid h4{color:#fff;font-size:.9rem;margin-bottom:14px;letter-spacing:.03em;text-transform:uppercase}
.footer-grid ul{list-style:none;margin:0;padding:0}
.footer-grid li{margin-bottom:9px}
.footer-grid a{color:#94a3b8;font-size:.88rem}
.footer-grid a:hover{color:#fff}
.footer-brand p{color:#94a3b8;font-size:.9rem;max-width:280px}
.footer-bottom{
  border-top:1px solid #1e293b;padding:18px 20px;text-align:center;font-size:.82rem;color:#64748b;
}

@media (max-width:900px){
  .tool-layout{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr}
}
@media (max-width:720px){
  .main-nav{position:fixed;top:64px;left:0;right:0;background:#fff;border-bottom:1px solid var(--border);
    flex-direction:column;padding:16px 20px;gap:14px;display:none;box-shadow:var(--shadow-md)}
  .main-nav.open{display:flex}
  .nav-toggle{display:block}
  .search-wrap{width:100%;order:3}
  .header-inner{flex-wrap:wrap}
  .field-row{grid-template-columns:1fr}
  .footer-grid{grid-template-columns:1fr 1fr;padding:36px 20px 20px}
}
@media (max-width:480px){
  .footer-grid{grid-template-columns:1fr}
}