:root{
  --max:960px; --gap:1rem; --radius:12px; --border:#eaeaea;
  --bg:#fff; --bg-soft:#f7f7fb; --text:#111; --muted:#5a5a5a; --link:#0d6efd;
  --accent: var(--link);
  --accent-bg: #e7f1ff;
}
*{box-sizing:border-box} html{-webkit-text-size-adjust:100%}
body{margin:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Helvetica,Arial,sans-serif;line-height:1.6;color:var(--text);background:var(--bg)}
img{max-width:100%;height:auto}
.container{max-width:var(--max);margin-inline:auto;padding:1rem}
main.container{padding-top:1rem;padding-bottom:2rem}

/* Header */
.site-header{background:var(--bg-soft);border-bottom:1px solid var(--border)}
.logo img{width: 350px; max-width: 100%; margin-bottom: 10px;}
.logo-mark{font-size:1.25rem}
.logo-text strong{color:var(--link)}
.main-nav{display:flex;gap:.75rem;flex-wrap:wrap}
.main-nav a,
.nav-drop-btn {
  text-decoration:none;
  color:inherit;
  padding:.5rem .75rem;
  border-radius:10px;
  border:1px solid transparent;
  background-color:#fff;
  cursor:pointer;
  font:inherit;
  display:inline-flex;
  align-items:center;
}
.main-nav a:hover,
.nav-drop-btn:hover {
  background:#d8d4d4;
  border-color:var(--border);
}
.main-nav a:focus-visible,
.nav-drop-btn:focus-visible {
  outline:2px dashed var(--link);
  outline-offset:2px;
}
.nav-drop-btn .chev {
  margin-left:.35rem;
  font-size:.85em;
}

/* Footer */
.site-footer{background:var(--bg-soft);border-top:1px solid var(--border)}
.site-footer p{margin:.25rem 0;color:var(--muted)}

/* Typography */
h1{font-size:clamp(1.6rem,3vw + 1rem,2.25rem);margin:.5rem 0 .75rem}
h2{font-size:clamp(1.25rem,2vw + .75rem,1.5rem);margin:1.25rem 0 .5rem}
.lede{color:var(--muted)}
.badge{font-size:.8rem;background:var(--bg-soft);padding:.15rem .4rem;border-radius:.5rem}

/* Lists & cards */
.grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:var(--gap);padding:0;list-style:none}
.cards{list-style:none;margin:0;padding:0}
.card{border:1px solid var(--border);border-radius:var(--radius);padding:1rem;background:#fff;box-shadow:0 1px 0 rgba(0,0,0,.02),0 6px 18px rgba(0,0,0,.05)}
.card h3{margin-top:0;margin-bottom:.5rem}

/* Forms */
label{display:block;font-weight:600;margin-bottom:.25rem}
input[type="date"],input[type="number"],input[type="text"],input[type="email"],input[type="search"]{
  width:100%;padding:.75rem .9rem;border:1px solid var(--border);border-radius:var(--radius);font-size:1rem;background:#fff
}
input:focus-visible{outline:2px dashed var(--link);outline-offset:2px}
button,.btn{display:inline-flex;align-items:center;justify-content:center;gap:.5rem;padding:.65rem .9rem;border-radius:var(--radius);border:1px solid var(--border);background:#fff;color:inherit;cursor:pointer}
button:hover,.btn:hover{background:var(--bg-soft)}
button:focus-visible{outline:2px dashed var(--link);outline-offset:2px}

/* Converter form grid */
.converter-form{display:grid;grid-template-columns:1fr 1fr auto;gap:.75rem;align-items:end;margin:1rem 0}
@media (max-width:720px){.converter-form{grid-template-columns:1fr}}

/* Utilities */
.visually-hidden{position:absolute!important;height:1px;width:1px;overflow:hidden;clip:rect(1px,1px,1px,1px);white-space:nowrap}
.mt-0{margin-top:0!important} .mb-0{margin-bottom:0!important}
.mx-auto{margin-inline:auto} .card--narrow{max-width:820px}

/* Breadcrumb */
.breadcrumb{margin:.25rem 0 1rem;font-size:.95rem}
.breadcrumb a{text-decoration:none}

/* Tables */
.table{width:100%;border-collapse:collapse}
.table th,.table td{padding:.5rem .75rem;border-bottom:1px solid var(--border);text-align:left}
.table thead th{font-weight:700}

/* --- Nav dropdown --- */
.nav-group { position: relative; }

.nav-submenu {
  display:none;
  position:absolute;
  top:calc(100% + .25rem);
  left:0;
  min-width:240px;
  margin:0;
  padding:.5rem 0;
  list-style:none;
  background:#fff;
  border:1px solid var(--border);
  border-radius:12px;
  box-shadow:0 6px 18px rgba(0,0,0,.08);
  z-index:20;
}
.nav-submenu li a {
  display:block;
  text-decoration:none;
  color:inherit;
  padding:.5rem .75rem;
  border-radius:8px;
  border:1px solid transparent;
}
.nav-submenu li a:hover {
  background:#d8d4d4;
  border-color:var(--border);
}

/* Only open when JS adds .is-open */
.nav-group.is-open .nav-submenu { display:block; }

/* Keep dropdown usable on narrow screens */
@media (max-width:720px){
  .nav-submenu { position:absolute; left:0; right:auto; width:min(85vw,320px); }
}

/* === Result hero (prominent answer line) === */
#result-line, #quick-table {
  display:block;
  border:1px solid var(--border);
  background:var(--accent-bg);
  border-left:6px solid var(--accent);
  border-radius:var(--radius);
  padding:1rem 1.25rem;
  font-weight:800;
  line-height:1.3;
  color:#0b3b8a;
  margin:0 0 1rem;
}

/* Spacing utility for cards that follow a hero */
.mt-1 { margin-top:1rem; }

#calc, #home-calc{display:none;}