:root {
  --bg-top: #07131f;
  --bg-bottom: #11273a;
  --card: rgba(9, 26, 39, 0.8);
  --stroke: rgba(242, 208, 120, 0.2);
  --text: #eff7f8;
  --muted: #adc5c7;
  --accent: #f2d078;
  --accent-strong: #ffb54c;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
  --radius-xl: 28px;
  --radius-md: 14px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Avenir Next", "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(242, 208, 120, 0.18), transparent 28%),
    radial-gradient(circle at bottom right, rgba(96, 180, 255, 0.12), transparent 24%),
    linear-gradient(160deg, var(--bg-top), var(--bg-bottom));
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.03) 1px, transparent 1px);
  background-size: 32px 32px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.5), transparent 85%);
}

.app-shell {
  width: min(860px, calc(100% - 32px));
  margin: 0 auto;
  padding: 48px 0 64px;
}

.hero-card,
.result-card {
  border: 1px solid var(--stroke);
  border-radius: var(--radius-xl);
  background: var(--card);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.hero-card {
  padding: 28px;
}

h1, h3 {
  margin-top: 0;
}

h1 {
  margin-bottom: 20px;
  font-size: clamp(2rem, 4.5vw, 3.2rem);
  line-height: 1.05;
}

.input-panel {
  display: grid;
  grid-template-columns: 1.2fr 1fr auto;
  gap: 14px;
}

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

.field span {
  color: var(--muted);
  font-size: 0.95rem;
}

.field input {
  width: 100%;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  padding: 15px 16px;
  font: inherit;
  outline: none;
  transition: border-color 180ms ease, transform 180ms ease, background 180ms ease;
}

.birth-date-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 10px;
}

.calendar-btn {
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text);
  font: inherit;
  padding: 0 14px;
  cursor: pointer;
  transition: border-color 180ms ease, transform 180ms ease, background 180ms ease;
}

.calendar-btn:hover {
  border-color: rgba(242, 208, 120, 0.8);
  background: rgba(255, 255, 255, 0.09);
  transform: translateY(-1px);
}

.picker-input {
  position: absolute;
  width: 1px;
  height: 1px;
  opacity: 0;
  pointer-events: none;
}

.field input:focus {
  border-color: rgba(242, 208, 120, 0.9);
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-1px);
}

.submit-btn {
  align-self: end;
  border: 0;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--accent), var(--accent-strong));
  color: #10151e;
  font: inherit;
  font-weight: 700;
  padding: 15px 22px;
  cursor: pointer;
  min-width: 170px;
  transition: transform 180ms ease, filter 180ms ease;
}

.submit-btn:hover {
  transform: translateY(-1px);
  filter: saturate(1.1);
}

.results-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
  gap: 16px;
  margin-top: 20px;
}

.result-card {
  padding: 22px;
  animation: rise 320ms ease both;
}

.result-card h3 {
  margin-bottom: 10px;
  color: var(--accent);
  font-size: 1.02rem;
  letter-spacing: 0.02em;
}

.result-value {
  margin: 0;
  font-size: clamp(2.4rem, 5vw, 4rem);
  font-weight: 800;
  line-height: 1;
}

.hidden {
  display: none;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(14px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 760px) {
  .app-shell {
    width: min(100% - 20px, 980px);
    padding: 20px 0 36px;
  }

  .hero-card,
  .result-card {
    border-radius: 22px;
  }

  .hero-card {
    padding: 20px;
  }

  .input-panel {
    grid-template-columns: 1fr;
  }

  .submit-btn {
    width: 100%;
  }
}