/* Conventions: variables + thèmes via data-theme sur <html> */
:root{
  --bg: #f4f4f6;
  --card: #ffffffcc;
  --text: #111217;
  --muted: #4b4f5c;
  --border: rgba(16,18,23,.12);
  --shadow: 0 10px 30px rgba(16,18,23,.08);
  --primary: #3f3f46;
  --primaryText: #ffffff;
  --focus: #2563eb;

  --inputBg: #ffffff;
  --inputText: #111217;
  --inputBorder: rgba(16,18,23,.16);

  --btnGhost: rgba(16,18,23,.06);
  --btnGhostHover: rgba(16,18,23,.10);

  --codeBg: rgba(16,18,23,.06);

  --radius: 14px;
  --gap: 14px;

  color-scheme: light;
}

html[data-theme="dark"]{
  --bg: #0f1115;
  --card: rgba(22,25,33,.78);
  --text: #f3f4f6;
  --muted: #b6bac6;
  --border: rgba(255,255,255,.12);
  --shadow: 0 18px 50px rgba(0,0,0,.35);

  --primary: #a3a3a3;
  --primaryText: #0f1115;
  --focus: #60a5fa;

  --inputBg: rgba(16,18,23,.55);
  --inputText: #f3f4f6;
  --inputBorder: rgba(255,255,255,.18);

  --btnGhost: rgba(255,255,255,.08);
  --btnGhostHover: rgba(255,255,255,.12);
  --codeBg: rgba(255,255,255,.08);

  color-scheme: dark;
}

*{ box-sizing: border-box; }

body{
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Arial, "Noto Sans", "Liberation Sans", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.4;
}

.skip-link{
  position: absolute;
  left: -999px;
  top: 10px;
  background: var(--primary);
  color: var(--primaryText);
  padding: 10px 12px;
  border-radius: 10px;
  z-index: 10;
}
.skip-link:focus{ left: 10px; outline: 3px solid var(--focus); }

.topbar{
  max-width: 980px;
  margin: 28px auto 0;
  padding: 0 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.logo{
  width: 70px;
  height: auto;
  border-radius: 90px;
  display: grid;
  place-items: center;
  display: block;
}
.title{
  margin: 0;
  font-size: 1.05rem;
  letter-spacing: .2px;
}
.subtitle{
  margin: 2px 0 0;
  color: var(--muted);
  font-size: .95rem;
}

.container{
  max-width: 980px;
  margin: 18px auto 34px;
  padding: 0 16px;
}

.card{
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 18px;
}

.card + .card{ margin-top: 16px; }

.form{
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--gap);
}

@media (max-width: 820px){
  .form{ grid-template-columns: 1fr; }
  .topbar{ flex-direction: column; align-items: flex-start; }
}

.field{
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.field label{
  font-weight: 700;
}

.help{
  margin: 0;
  color: var(--muted);
  font-size: .92rem;
}

input, select, button{
  font: inherit;
}

input[type="number"], select{
  background: var(--inputBg);
  color: var(--inputText);
  border: 1px solid var(--inputBorder);
  border-radius: 12px;
  padding: 11px 12px;
  outline: none;
}

input[type="number"]:focus, select:focus, .theme-btn:focus, button:focus{
  outline: 3px solid color-mix(in srgb, var(--focus) 60%, transparent);
  outline-offset: 2px;
}

.actions{
  grid-column: 1 / -1;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
}

.primary, .ghost, .ex, .theme-btn{
  border-radius: 12px;
  border: 1px solid transparent;
  padding: 11px 14px;
  cursor: pointer;
  user-select: none;
}

.primary{
  background: var(--primary);
  color: var(--primaryText);
  font-weight: 800;
}
.primary:hover{ filter: brightness(1.03); }

.ghost{
  background: var(--btnGhost);
  color: var(--text);
  border-color: var(--border);
}
.ghost:hover{ background: var(--btnGhostHover); }

.theme{
  display: flex;
  align-items: center;
  gap: 12px;
}
.theme-btn{
  background: var(--btnGhost);
  border-color: var(--border);
  color: var(--text);
  display: inline-flex;
  align-items: center;
  gap: 10px;
}
.theme-icon{
  width: 28px;
  height: 28px;
  display: grid;
  place-items: center;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--inputBg) 45%, transparent);
}

.theme-hint{
  min-height: 1.1em;
  color: var(--muted);
  font-size: .92rem;
}

.result{
  grid-column: 1 / -1;
  margin-top: 2px;
  padding: 14px;
  border-radius: 12px;
  border: 1px solid var(--border);
  background: color-mix(in srgb, var(--inputBg) 35%, transparent);
}
.result-line{
  display: flex;
  gap: 10px;
  align-items: baseline;
  flex-wrap: wrap;
}
.result-label{
  font-weight: 800;
}
.result-value{
  font-weight: 900;
  font-size: 1.25rem;
}
.result-details{
  margin-top: 8px;
  color: var(--muted);
}

.extras{
  grid-column: 1 / -1;
  margin-top: 6px;
  padding-top: 10px;
  border-top: 1px solid var(--border);
  display: grid;
  gap: 12px;
}
.extras h3{
  margin: 0;
  font-size: 1rem;
}

.toggle-row{
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
}
.checkbox{
  display: flex;
  align-items: center;
  gap: 10px;
  background: color-mix(in srgb, var(--inputBg) 40%, transparent);
  border: 1px solid var(--border);
  padding: 10px 12px;
  border-radius: 12px;
}
.checkbox input{ width: 18px; height: 18px; }

.field-inline{
  display: flex;
  align-items: center;
  gap: 10px;
}
.field-inline label{
  font-weight: 800;
}

.tip ul{
  margin: 12px 0 0;
  padding-left: 18px;
}
.ex{
  padding: 9px 12px;
}

.footer{
  max-width: 980px;
  margin: 0 auto 28px;
  padding: 0 16px;
  color: var(--muted);
  font-size: .95rem;
}

/* Accessibilité: si le navigateur ne sait pas gérer color-mix, on garde de bons contrastes via variables */
