:root {
  --primary: #28a745;
  --primary-dark: #218838;
  --bg: #f1f1f1;
  --text: #2c3e50;
  --muted: #6c757d;
  --error-bg: #fdecea;
  --error-text: #c0392b;
  --success-bg: #e8f8f5;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "IBM Plex Sans", sans-serif;
  background: var(--bg);
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 1rem;
}

.box {
  background: #fff;
  padding: 2.2rem 2rem;
  border-radius: 12px;
  width: 100%;
  max-width: 420px;
  text-align: center;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
  animation: fadeIn 0.4s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

h2 {
  font-family: "IBM Plex Sans", sans-serif;
  color: var(--text);
  margin-bottom: 0.5rem;
}

.subtitle {
  font-size: 0.9rem;
  color: var(--muted);
  margin-bottom: 1.5rem;
}

input {
  width: 100%;
  padding: 13px 14px;
  margin-bottom: 1rem;
  border-radius: 8px;
  border: 1px solid #ccc;
  font-size: 0.95rem;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(40, 167, 69, 0.15);
}

button {
  width: 100%;
  background: var(--primary);
  color: #fff;
  padding: 13px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-weight: 600;
  font-size: 0.95rem;
  transition: all 0.25s ease;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.12);
}

button:hover {
  background: var(--primary-dark);
  transform: translateY(-1px);
}

button:disabled {
  opacity: 0.7;
  cursor: not-allowed;
  transform: none;
}

.message {
  margin-top: 1.2rem;
  padding: 0.9rem;
  border-radius: 8px;
  font-size: 0.9rem;
  display: none;
}

.message.error {
  background: var(--error-bg);
  color: var(--error-text);
}

.message.success {
  background: var(--success-bg);
  color: #2d3436;
}