:root {
  --bg: #071a1a;
  --bg-soft: #0b2b2b;
  --card: #0f2f2f;
  --card-border: #134e4a;

  --text: #e6fffa;
  --muted: #94a3b8;

  --teal: #14b8a6;
  --teal-dark: #0f766e;
  --teal-soft: rgba(20, 184, 166, 0.2);

  --error: #ef4444;
}

* {
  box-sizing: border-box;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

body {
  margin: 0;
  height: 100vh;

  background:
    radial-gradient(circle at 20% 20%, rgba(20,184,166,0.15), transparent 40%),
    radial-gradient(circle at 80% 0%, rgba(20,184,166,0.08), transparent 50%),
    var(--bg);

  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text);
}

.card {
  background: linear-gradient(145deg, #0f2f2f, #0b2626);
  border: 1px solid var(--card-border);
  padding: 32px;
  border-radius: 16px;
  width: 320px;
  box-shadow:
    0 20px 40px rgba(0,0,0,0.5),
    0 0 0 1px rgba(20,184,166,0.05);
  animation: fadeIn 0.4s ease;
}

.card.error {
  animation: shake 0.3s;
}

h2 {
  text-align: center;
  margin-bottom: 20px;
}

.error-box {
  background: rgba(239,68,68,0.1);
  border: 1px solid rgba(239,68,68,0.3);
  color: var(--error);
  padding: 10px;
  border-radius: 8px;
  margin-bottom: 16px;
  font-size: 13px;
  text-align: center;
}

.field {
  position: relative;
  margin-bottom: 20px;
}

input {
  width: 100%;
  padding: 14px;
  background: rgba(255,255,255,0.02);
  border: 1px solid var(--card-border);
  border-radius: 8px;
  color: var(--text);
  outline: none;
}

input:focus {
  border-color: var(--teal);
  box-shadow: 0 0 0 2px var(--teal-soft);
}

input.error {
  border-color: var(--error);
  box-shadow: 0 0 0 2px rgba(239,68,68,0.2);
}

button {
  width: 100%;
  padding: 12px;
  border: none;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--teal), var(--teal-dark));
  color: var(--text);
  font-weight: bold;
  cursor: pointer;
}

button:hover {
  box-shadow: 0 8px 20px rgba(20, 184, 166, 0.3);
}

.hint {
  margin-top: 12px;
  font-size: 12px;
  text-align: center;
  color: var(--muted);
}

@keyframes shake {
  0% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  50% { transform: translateX(6px); }
  75% { transform: translateX(-4px); }
  100% { transform: translateX(0); }
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}