:root {
  --bg: #0b1020;
  --text: rgba(255, 255, 255, 0.92);
  --muted: rgba(255, 255, 255, 0.70);
  --card: rgba(255, 255, 255, 0.10);
  --line: rgba(255, 255, 255, 0.16);
  --accent: #ff3b3b;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background: radial-gradient(900px 500px at 20% 15%, rgba(120,80,255,.35), transparent 55%),
              radial-gradient(900px 500px at 80% 25%, rgba(0,200,255,.25), transparent 55%),
              radial-gradient(900px 500px at 50% 90%, rgba(255,150,0,.12), transparent 55%),
              var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}

.wrap {
  width: min(860px, 100%);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 32px 20px;
  backdrop-filter: blur(10px);
}

.header {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 22px;
  text-align: center;
}

.badge {
  display: inline-flex;
  align-self: center;
  width: fit-content;
  padding: 6px 10px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: rgba(255,255,255,0.08);
  font-weight: 600;
  letter-spacing: 0.2px;
  font-size: 12px;
}

h1 {
  margin: 0;
  font-size: clamp(28px, 5vw, 44px);
  color: var(--accent);
}

.sub {
  margin: 0;
  color: var(--muted);
}

.calculator {
  margin: 26px auto 0;
  padding: 22px;
  background: rgba(0, 0, 0, 0.18);
  border: 1px solid var(--line);
  border-radius: 14px;
  width: min(520px, 100%);
}

.calculator h2 {
  margin: 0 0 14px;
  font-size: 18px;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-bottom: 12px;
}

.field label {
  font-size: 13px;
  color: var(--muted);
}

.field input {
  padding: 12px 12px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,0.06);
  color: var(--text);
  outline: none;
}

.field input:focus {
  border-color: rgba(255, 59, 59, 0.6);
  box-shadow: 0 0 0 3px rgba(255, 59, 59, 0.18);
}

button {
  width: 100%;
  padding: 12px 14px;
  border: none;
  border-radius: 12px;
  background: var(--accent);
  color: white;
  font-weight: 700;
  cursor: pointer;
}

button:hover { opacity: 0.92; }

.result {
  margin-top: 14px;
  padding: 12px;
  border-radius: 12px;
  border: 1px dashed rgba(255,255,255,0.22);
  color: var(--text);
  min-height: 44px;
}

.footer {
  margin-top: 18px;
  text-align: center;
  color: var(--muted);
}