:root {
  --color-bg:    #f9fafb;
  --color-card:  #ffffff;
  --color-primary: #3b82f6;
  --color-accent:  #1c8a65;
  --color-text:  #1f2937;
  --color-muted: #6b7280;
  --radius:      0.5rem;
  --spacing:     1rem;
  --font-sans: 'Inter', sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}
body {
  margin: 0;
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: 100vh;
  padding: var(--spacing);
}

a {
  color: var(--color-primary);
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  background-color: var(--color-primary);
  color: white;
  border: none;
  border-radius: var(--radius);
  padding: 0.6rem 1rem;
  font-size: 0.95rem;
  font-weight: 500;
  transition: background 0.2s, transform 0.1s;
}
button:hover:not(:disabled) {
  background: var(--color-accent);
}
button:active:not(:disabled) {
  transform: scale(0.97);
}
button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

/* ─── Login (original style) ─────────────────────── */
#login {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  max-width: 400px;
  width: 100%;
  margin-top: 100px;
}
#login h2 {
  color: var(--color-primary);
  font-size: 2rem;
  margin-bottom: var(--spacing);
}
#login input {
  width: 100%;
  padding: 0.75rem;
  margin-bottom: var(--spacing);
  font-size: 1rem;
  border: 1px solid #d1d5db;
  border-radius: var(--radius);
}
#login button {
  width: 100%;
  margin-bottom: var(--spacing);
}

/* ─── App Container ──────────────────────────────── */
#app {
  width: 100%;
  max-width: 900px;
}

/* ─── Cards ──────────────────────────────────────── */
.card {
  background: var(--color-card);
  border-radius: var(--radius);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
  padding: var(--spacing);
  margin-bottom: var(--spacing);
  text-align: center;
}

/* ─── Control Section ────────────────────────────── */
.controls {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing);
  justify-content: center;
}

.control-card {
  flex: 1 1 300px;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.control-card h1 {
  font-size: 1.5rem;
  color: var(--color-primary);
  margin: 0.5rem 0;
}

.button-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
  width: 100%;
  margin-top: var(--spacing);
}

/* ─── Classification ─────────────────────────────── */
#classification {
  display: inline-block;
  margin-top: 0.5rem;
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--color-accent);
}

/* ─── Years ───────────────────────────────────────── */
#years-container {
  padding: var(--spacing);
}

/* ─── Saved Message ──────────────────────────────── */
#save-msg {
  margin-top: 0.5rem;
  color: var(--color-accent);
}