:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --bg-body: #0f172a;
  --bg-card: #1e293b;
  --text-main: #f1f5f9;
  --text-muted: #94a3b8;
  --border: rgba(255,255,255,.1);
  --error-bg: rgba(239,68,68,.15);
  --error-text: #fca5a5;
  --success-bg: rgba(34,197,94,.15);
  --success-text: #86efac;
}

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

body {
  font-family: 'Inter', -apple-system, sans-serif;
  background: var(--bg-body);
  background-image: radial-gradient(ellipse at 20% 50%, rgba(37,99,235,.15) 0%, transparent 60%),
                    radial-gradient(ellipse at 80% 20%, rgba(99,102,241,.1) 0%, transparent 50%);
  color: var(--text-main);
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  padding: 20px;
}

.card {
  background: var(--bg-card);
  width: 100%;
  max-width: 420px;
  padding: 2.5rem;
  border-radius: 24px;
  border: 1px solid var(--border);
  box-shadow: 0 25px 50px -12px rgba(0,0,0,.5);
  text-align: center;
  animation: slideUp .5s ease-out;
}

.card-icon {
  width: 60px; height: 60px;
  background: rgba(37,99,235,.15);
  border: 1px solid rgba(37,99,235,.3);
  border-radius: 16px;
  display: flex; align-items: center; justify-content: center;
  margin: 0 auto 20px;
}

h2 {
  font-size: 1.6rem;
  font-weight: 800;
  color: var(--text-main);
  margin-bottom: 4px;
}

.subtitle {
  font-size: .85rem;
  color: var(--text-muted);
  margin-bottom: 28px;
  font-weight: 500;
  letter-spacing: .04em;
  text-transform: uppercase;
}

p {
  color: var(--text-muted);
  font-size: .9rem;
  margin-bottom: 20px;
  line-height: 1.5;
}

input {
  width: 100%;
  padding: 13px 16px;
  margin-bottom: 12px;
  border: 1px solid var(--border);
  border-radius: 12px;
  font-size: 1rem;
  background: rgba(255,255,255,.05);
  color: var(--text-main);
  transition: all .2s;
  font-family: inherit;
}

input::placeholder { color: var(--text-muted); }

input:focus {
  outline: none;
  border-color: var(--primary);
  background: rgba(37,99,235,.08);
  box-shadow: 0 0 0 4px rgba(37,99,235,.15);
}

button {
  width: 100%;
  padding: 13px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  transition: background .2s, transform .1s;
  font-family: inherit;
}

button:hover { background: var(--primary-hover); }
button:active { transform: scale(.98); }

.msg {
  padding: 12px 16px;
  border-radius: 10px;
  font-size: .85rem;
  margin-bottom: 20px;
  font-weight: 500;
  text-align: left;
}

.error { background: var(--error-bg); color: var(--error-text); border: 1px solid rgba(239,68,68,.2); }
.success { background: var(--success-bg); color: var(--success-text); border: 1px solid rgba(34,197,94,.2); }

.code-input {
  letter-spacing: 14px;
  text-align: center;
  font-size: 2rem;
  font-weight: 800;
  color: #60a5fa;
  padding: 16px;
}

.btn-back {
  display: inline-block;
  color: var(--text-muted);
  text-decoration: none;
  font-size: .85rem;
  transition: color .2s;
}

.btn-back:hover { color: var(--primary); }

@keyframes slideUp {
  from { opacity: 0; transform: translateY(24px); }
  to   { opacity: 1; transform: translateY(0); }
}