/* ===== Variables ===== */
:root {
  --bg: #0f0f0f;
  --card: #1a1a1a;
  --accent: #ff6b35;
  --text: #ffffff;
  --text-dim: #888888;
  --border: #333333;
}

/* ===== Reset ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* ===== Base ===== */
html, body {
  height: 100%;
}

body {
  font-family: 'Space Grotesk', -apple-system, sans-serif;
  background: var(--bg);
  color: var(--text);
  margin: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
}

/* ===== Layout ===== */
.container {
  width: 100%;
  max-width: 400px;
  min-height: 100%;
  display: flex;
  flex-direction: column;
  padding: 24px;
  text-align: center;
}

.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

header {
  margin-bottom: 32px;
}

h1 {
  font-size: 2rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 8px;
}

.emoji {
  font-size: 3.5rem;
  margin-bottom: 8px;
}

.tagline {
  color: var(--text-dim);
  font-size: 0.95rem;
  margin-bottom: 32px;
}

/* ===== Input ===== */
.input-group {
  margin-bottom: 24px;
}

.input-group label {
  display: block;
  font-size: 0.8rem;
  color: var(--text-dim);
  text-transform: uppercase;
  letter-spacing: 0.1em;
  margin-bottom: 12px;
}

#birthYear {
  width: 100%;
  max-width: 200px;
  padding: 16px 24px;
  font-size: 1.5rem;
  font-family: inherit;
  font-weight: 600;
  text-align: center;
  background: var(--card);
  border: 2px solid var(--border);
  border-radius: 12px;
  color: var(--text);
  transition: border-color 0.2s, box-shadow 0.2s;
}

#birthYear:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(255, 107, 53, 0.15);
}

#birthYear::placeholder {
  color: var(--text-dim);
}

/* Hide number spinners */
#birthYear::-webkit-inner-spin-button,
#birthYear::-webkit-outer-spin-button {
  -webkit-appearance: none;
}

/* ===== Result ===== */
.result {
  transition: opacity 0.3s, transform 0.3s;
}

.result.hidden {
  opacity: 0;
  transform: translateY(10px);
  pointer-events: none;
}

.count {
  font-size: 4rem;
  font-weight: 700;
  color: var(--accent);
}

.count span {
  display: inline-block;
  animation: pop 0.4s ease-out;
}

@keyframes pop {
  0% { transform: scale(0.8); opacity: 0; }
  50% { transform: scale(1.1); }
  100% { transform: scale(1); opacity: 1; }
}

/* ===== Ad Container ===== */
.ad-container {
  margin-top: 24px;
  width: 100%;
  max-height: 100px; /* Force limit to prevent ad from breaking layout */
  overflow: hidden;
}

/* ===== Footer ===== */
footer {
  margin-top: auto;
  padding: 24px 0 0;
  color: var(--text-dim);
  font-size: 0.8rem;
  text-align: center;
}

/* ===== Responsive ===== */
@media (max-width: 480px) {
  h1 {
    font-size: 1.75rem;
  }
  
  .count {
    font-size: 3rem;
  }
}