/* calculator.css: the look of the web app and of the admin app (CALC-05, CALC-10). Dark or light as the device is set;
   one column at phone width, the calculator and the history side by side on a wider screen. The admin's colour is
   body[data-colour] (1, 2 or 3); normal mode (body[data-mode="normal"]) hides every scientific key. */

:root {
  color-scheme: dark;
  --bg: #05070f;
  --bg-glow: #12204a;
  --panel: rgb(18 24 46 / 0.72);
  --key: rgb(255 255 255 / 0.05);
  --key-hover: rgb(255 255 255 / 0.11);
  --line: rgb(148 163 184 / 0.18);
  --text: #e6ecff;
  --muted: #94a3c4;
  --bad: #fb7185;
  --good: #34d399;
  --accent: #22d3ee;
  --font: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Mono", Menlo, Consolas, monospace;
}
body[data-colour="2"] { --accent: #a78bfa; }
body[data-colour="3"] { --accent: #fbbf24; }


* { box-sizing: border-box; }
html { min-height: 100%; }
body {
  margin: 0;
  min-height: 100vh;
  font: 16px/1.45 var(--font);
  color: var(--text);
  background:
    radial-gradient(60rem 40rem at 85% -10%, color-mix(in srgb, var(--accent) 22%, transparent), transparent 60%),
    radial-gradient(50rem 35rem at -10% 110%, var(--bg-glow), transparent 60%),
    repeating-linear-gradient(0deg, var(--line) 0 1px, transparent 1px 48px),
    repeating-linear-gradient(90deg, var(--line) 0 1px, transparent 1px 48px),
    var(--bg);
  background-attachment: fixed;
}

/* ── the bar ─────────────────────────────────────────────────────────────────────────────────────── */
.bar {
  display: flex; flex-wrap: wrap; gap: .75rem; align-items: center; justify-content: space-between;
  max-width: 64rem; margin: 0 auto; padding: 1.25rem 1rem .5rem;
}
h1 {
  margin: 0; font-size: 1.5rem; font-weight: 700; letter-spacing: .14em; text-transform: uppercase;
  background: linear-gradient(90deg, var(--text), var(--accent));
  -webkit-background-clip: text; background-clip: text; color: transparent;
}
.head { display: flex; flex-direction: column; gap: .15rem; }
.tagline { margin: 0; color: var(--muted); font-size: .85rem; }
.who { display: flex; gap: .5rem; align-items: center; }
.person { color: var(--muted); font-size: .9rem; }
.person::before { content: "● "; color: var(--good); }

button { font: inherit; color: inherit; cursor: pointer; }
button:focus-visible, input:focus-visible, a:focus-visible, label:focus-within {
  outline: 2px solid var(--accent); outline-offset: 2px;
}
.ghost {
  border: 1px solid color-mix(in srgb, var(--accent) 55%, transparent); background: transparent;
  border-radius: 999px; padding: .4rem .9rem; font-size: .9rem;
}
.ghost:hover { background: color-mix(in srgb, var(--accent) 14%, transparent); }
.ghost:disabled { opacity: .45; cursor: not-allowed; }

/* ── the layout ──────────────────────────────────────────────────────────────────────────────────── */
.layout {
  display: grid; gap: 1rem; grid-template-columns: 1fr;
  max-width: 64rem; margin: 0 auto; padding: .5rem 1rem;
}
@media (min-width: 52rem) { .layout { grid-template-columns: minmax(0, 23rem) minmax(0, 1fr); align-items: start; } }

.card {
  background: var(--panel); border: 1px solid var(--line); border-radius: 1.25rem; padding: 1rem;
  backdrop-filter: blur(14px); -webkit-backdrop-filter: blur(14px);
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--accent) 10%, transparent), 0 24px 60px rgb(0 0 0 / .28);
}

/* ── the screen ──────────────────────────────────────────────────────────────────────────────────── */
.screen {
  border-radius: .9rem; padding: .75rem .9rem; margin-bottom: .75rem;
  background: color-mix(in srgb, var(--bg) 70%, transparent);
  border: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
  box-shadow: inset 0 0 24px color-mix(in srgb, var(--accent) 12%, transparent);
}
#expression {
  width: 100%; border: 0; background: transparent; color: var(--muted);
  font: 1.05rem/1.4 var(--mono); text-align: right;
}
#expression:focus { outline: none; color: var(--text); }
#result {
  display: block; text-align: right; overflow-wrap: anywhere;
  font: 600 2.4rem/1.15 var(--mono); color: var(--accent);
  text-shadow: 0 0 18px color-mix(in srgb, var(--accent) 55%, transparent);
}
#result.refused { color: var(--bad); text-shadow: none; }
.said { min-height: 1.3em; margin: .25rem 0 0; text-align: right; font-size: .85rem; color: var(--muted); }

.tools { display: flex; justify-content: space-between; align-items: center; margin-bottom: .6rem; }
.angle { display: inline-flex; border: 1px solid var(--line); border-radius: 999px; overflow: hidden; }
.angle button { border: 0; background: transparent; padding: .3rem .8rem; font: 600 .8rem var(--mono); color: var(--muted); }
.angle button[aria-pressed="true"] { background: color-mix(in srgb, var(--accent) 22%, transparent); color: var(--text); }
.mode { margin-left: auto; font: .75rem var(--mono); letter-spacing: .12em; text-transform: uppercase; color: var(--muted); }
.mode::after { content: "scientific"; }
body[data-mode="normal"] .mode::after { content: "normal"; }
body[data-mode="normal"] .sci { display: none; }

/* ── the keys ────────────────────────────────────────────────────────────────────────────────────── */
.keys { display: grid; gap: .45rem; margin-bottom: .45rem; }
.keys.sci { grid-template-columns: repeat(5, 1fr); }
.keys.basic { grid-template-columns: repeat(4, 1fr); }
.keys button {
  min-height: 3rem; border-radius: .8rem; border: 1px solid var(--line); background: var(--key);
  font: 500 1.1rem var(--mono); transition: background .12s, transform .06s, box-shadow .12s;
}
.keys.sci button { min-height: 2.5rem; font-size: .9rem; color: var(--muted); }
.keys button:hover { background: var(--key-hover); box-shadow: 0 0 14px color-mix(in srgb, var(--accent) 25%, transparent); }
.keys button:active { transform: scale(.96); }
.keys .op { color: var(--accent); }
.keys .equals {
  grid-column: span 2; border: 0; color: #04111a; font-weight: 700;
  background: linear-gradient(135deg, var(--accent), color-mix(in srgb, var(--accent) 60%, #ffffff));
  box-shadow: 0 0 22px color-mix(in srgb, var(--accent) 45%, transparent);
}

/* ── the history ─────────────────────────────────────────────────────────────────────────────────── */
h2 { margin: 0 0 .5rem; font-size: .8rem; letter-spacing: .18em; text-transform: uppercase; color: var(--muted); }
.note { color: var(--muted); font-size: .9rem; margin: 0 0 .5rem; }
#history { list-style: none; margin: 0; padding: 0; display: grid; gap: .5rem; }
#history li { border: 1px solid var(--line); border-radius: .8rem; padding: .6rem .75rem; background: var(--key); }
.line { display: flex; justify-content: space-between; gap: .75rem; font-family: var(--mono); }
.line .expr { color: var(--muted); overflow-wrap: anywhere; }
.line .res { color: var(--accent); font-weight: 600; white-space: nowrap; background: none; border: 0; padding: 0; }
.meta { display: flex; flex-wrap: wrap; gap: .35rem .9rem; align-items: center; margin-top: .35rem; font-size: .85rem; color: var(--muted); }
.meta a, .link { color: var(--accent); background: none; border: 0; padding: 0; font-size: .85rem; text-decoration: underline; }
.meta .danger { color: var(--bad); }
.attach input { position: absolute; width: 1px; height: 1px; opacity: 0; }

/* ── the services the calculator uses (CALC-08: each says, in words, why it is unavailable) ──────── */
.services {
  display: grid; gap: .5rem; grid-template-columns: 1fr;
  max-width: 64rem; margin: 0 auto; padding: .75rem 1rem 2rem;
}
@media (min-width: 52rem) { .services { grid-template-columns: repeat(3, 1fr); } }
.feature { margin: 0; font-size: .8rem; color: var(--muted); border-left: 3px solid var(--line); padding-left: .6rem; }
.feature b { color: var(--text); }
.feature.on { border-left-color: var(--good); }
.feature.off { border-left-color: var(--bad); }
.feature span { display: block; }

/* ── the admin app ───────────────────────────────────────────────────────────────────────────────── */
.admin-card { max-width: 36rem; margin: 1.5rem auto; }
.admin-card fieldset { border: 1px solid var(--line); border-radius: .8rem; margin: 0 0 1rem; padding: .75rem; }
.admin-card legend { padding: 0 .4rem; color: var(--muted); font-size: .85rem; }
.admin-card label { display: flex; gap: .6rem; align-items: center; padding: .35rem 0; }
.swatches { display: flex; gap: 1rem; flex-wrap: wrap; }
.swatch::before { content: ""; width: 1.4rem; height: 1.4rem; border-radius: 50%; order: 2; }
.swatch.c1::before { background: #22d3ee; }
.swatch.c2::before { background: #a78bfa; }
.swatch.c3::before { background: #fbbf24; }
.admin-card .said { text-align: left; }
input[type="radio"] { accent-color: var(--accent); }
.save { border: 0; border-radius: 999px; padding: .55rem 1.4rem; font-weight: 700; color: #04111a; background: var(--accent); }

@media (prefers-color-scheme: light) {
  :root {
    color-scheme: light;
    --bg: #eef2fb;
    --bg-glow: #c7d7ff;
    --panel: rgb(255 255 255 / 0.82);
    --key: rgb(15 23 42 / 0.05);
    --key-hover: rgb(15 23 42 / 0.1);
    --line: rgb(15 23 42 / 0.12);
    --text: #0b1430;
    --muted: #4b5875;
    --bad: #be123c;
    --good: #047857;
    --accent: #0e7490;
  }
  body[data-colour="2"] { --accent: #6d28d9; }
  body[data-colour="3"] { --accent: #b45309; }
  .keys .equals, .save { color: #ffffff; }
}