/* ---- Base ---- */
:root {
  --bg: #04070b;           /* deep terminal dark */
  --card: #0a0f17;         /* panel */
  --text: #d7fbe8;         /* soft green */
  --muted: #7fbfa5;        /* muted green */
  --primary: #19ff90;      /* neon green */
  --primary-600: #0fd67a;  /* darker neon */
  --danger: #ff6b6b;
  --ring: rgba(25, 255, 144, 0.25);
  --grid: rgba(25, 255, 144, 0.04);
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f6fff9;
    --card: #ffffff;
    --text: #0e2a1e;
    --muted: #2f6a50;
    --primary: #008f4a;
    --primary-600: #006a37;
    --ring: rgba(0, 143, 74, 0.2);
    --grid: rgba(0, 143, 74, 0.08);
  }
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  font-family: "JetBrains Mono", ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  background:
    linear-gradient(0deg, transparent 24%, var(--grid) 25%, var(--grid) 26%, transparent 27%, transparent 74%, var(--grid) 75%, var(--grid) 76%, transparent 77%),
    linear-gradient(90deg, transparent 24%, var(--grid) 25%, var(--grid) 26%, transparent 27%, transparent 74%, var(--grid) 75%, var(--grid) 76%, transparent 77%),
    radial-gradient(1200px 800px at 10% 10%, #07110d 0%, var(--bg) 55%);
  background-size: 40px 40px, 40px 40px, auto;
  color: var(--text);
}

/* ---- Layout ---- */
.app {
  min-height: 100dvh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.card {
  width: min(720px, 100%);
  background: var(--card);
  border: 1px solid rgba(25,255,144,0.2);
  border-radius: 16px;
  padding: 28px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.45), inset 0 0 0 1px rgba(255,255,255,0.02);
}

h1 {
  margin: 0 0 12px;
  font-size: 26px;
  letter-spacing: 0.5px;
}

/* ---- Form ---- */
.form { margin-top: 8px; }
.field { margin-bottom: 16px; }
label { display: block; margin-bottom: 6px; font-weight: 600; }
input[type="text"],
input[type="date"] {
  width: 100%;
  padding: 12px 14px;
  border-radius: 8px;
  border: 1px solid rgba(25,255,144,0.25);
  background: rgba(0,0,0,0.35);
  color: var(--text);
  outline: none;
  transition: box-shadow .15s ease, border-color .15s ease, background .2s;
}
input[type="text"]:focus,
input[type="date"]:focus {
  border-color: var(--primary-600);
  box-shadow: 0 0 0 4px var(--ring), 0 0 0 1px var(--primary-600) inset;
  background: rgba(0,0,0,0.25);
}

.help { color: var(--muted); }
.error { color: var(--danger); min-height: 1.2em; margin: 6px 0 0; }

.actions { display: flex; gap: 10px; }
.btn {
  appearance: none;
  border: 1px solid rgba(25,255,144,0.25);
  background: rgba(0,0,0,0.3);
  color: var(--text);
  padding: 10px 14px;
  border-radius: 8px;
  cursor: pointer;
  font-weight: 600;
  transition: transform .05s ease, background .2s ease, border-color .2s ease;
}
.btn:hover { background: rgba(25,255,144,0.06); border-color: rgba(25,255,144,0.35); }
.btn:active { transform: translateY(1px); }
.btn.primary { background: linear-gradient(180deg, var(--primary), var(--primary-600)); border-color: rgba(25,255,144,0.35); color: #04140c; }

/* ---- Results ---- */
.results {
  margin-top: 18px;
  display: grid;
  gap: 16px;
}

.result-block {
  padding: 16px;
  border-radius: 12px;
  background: rgba(0,0,0,0.25);
  border: 1px solid rgba(25,255,144,0.18);
}

.age-display {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 8px;
}

.age-part {
  display: grid;
  gap: 4px;
  padding: 12px;
  border-radius: 10px;
  background: rgba(0,0,0,0.2);
  border: 1px solid rgba(25,255,144,0.14);
  text-align: center;
}

.age-part span:first-child {
  font-size: 34px;
  font-weight: 700;
}

.age-part .label { color: var(--muted); font-size: 12px; letter-spacing: 0.5px; }

.footnote { margin-top: 10px; color: var(--muted); font-size: 12px; }

.devinfo {
  margin-top: 8px;
  color: var(--muted);
  font-size: 12px;
  border-top: 1px dashed rgba(25,255,144,0.25);
  padding-top: 10px;
}
.devinfo a {
  color: var(--primary);
  text-decoration: none;
  border-bottom: 1px dotted rgba(25,255,144,0.4);
}
.devinfo a:hover { text-decoration: underline; }

/* ---- Responsive ---- */
@media (max-width: 640px) {
  .age-display { grid-template-columns: 1fr; }
}