:root {
  --bg: #f8f9fa;
  --card-bg: #ffffff;
  --text: #14181b;
  --muted: #6c757d;
  --primary: #184027;
  --hover: #225c38;
  --error: #d32f2f;
  --radius: 12px;
  --font: 'Inter', sans-serif;
  --font-display: 'Inter Tight', sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px;
}

header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 24px;
}

header .logo {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

header h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.5rem;
  margin: 0;
}

.card {
  margin-top: 36px;
  width: 100%;
  max-width: 530px;
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 32px 24px;
  box-shadow: 0 2px 6px rgba(0,0,0,0.05);
}

h2 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.75rem;
  margin: 0 0 8px;
}

p {
  color: var(--muted);
  margin: 0 0 24px;
}

form {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

label {
  font-weight: 500;
}

input {
  padding: 16px;
  border: 1px solid #dee2e6;
  border-radius: var(--radius);
  font-size: 1rem;
}

button {
  background: var(--primary);
  color: white;
  border: none;
  border-radius: 40px;
  padding: 14px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
box-shadow: 0px 3px 1px -2px rgba(0, 0, 0, 0.2), 
            0px 2px 2px 0px rgba(0, 0, 0, 0.14), 
            0px 1px 5px 0px rgba(0, 0, 0, 0.12);
}

button:hover {
  background: var(--hover);
}

.hidden {
  display: none;
}

#message {
  padding: 16px;
  background: #e9ecef;
  border-radius: var(--radius);
  font-weight: 500;
}

footer {
  margin-top: auto;
  text-align: center;
  font-size: 0.8rem;
  color: var(--muted);
  padding: 16px;
}