:root {
  --bg: #eef3fa;
  --card: #ffffff;
  --line: #d8e2ee;
  --text: #0f172a;
  --muted: #64748b;
  --accent: #02c9ff;
}
* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Montserrat, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  background: radial-gradient(1200px 600px at 10% -10%, #d9f4ff, transparent 65%), var(--bg);
  color: var(--text);
}
.auth-page {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 16px;
}
.auth-card {
  width: min(460px, 100%);
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
  box-shadow: 0 16px 40px rgba(15, 23, 42, .08);
}
h1 {
  margin: 0;
  font-size: 24px;
}
.sub {
  margin: 6px 0 12px;
  color: var(--muted);
  font-size: 13px;
}
.tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-bottom: 12px;
}
.tab {
  border: 1px solid var(--line);
  background: #f8fbff;
  border-radius: 10px;
  height: 40px;
  font: inherit;
  cursor: pointer;
}
.tab.is-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #001018;
  font-weight: 700;
}
.form {
  display: none;
  gap: 10px;
}
.form.is-active {
  display: grid;
}
label {
  display: grid;
  gap: 6px;
  font-size: 13px;
}
input {
  width: 100%;
  border: 1px solid #cfd8e3;
  border-radius: 10px;
  height: 40px;
  padding: 0 12px;
  font: inherit;
}
button[type="submit"] {
  margin-top: 2px;
  height: 40px;
  border: 0;
  border-radius: 10px;
  background: #0f172a;
  color: #f8fbff;
  font: inherit;
  cursor: pointer;
}
button[type="submit"]:disabled {
  opacity: .55;
  cursor: not-allowed;
}
.msg {
  min-height: 20px;
  margin: 10px 0 0;
  font-size: 13px;
}
.msg.is-error { color: #b91c1c; }
.msg.is-ok { color: #166534; }
@media (max-width: 640px) {
  .auth-card {
    border-radius: 12px;
    padding: 14px;
  }
}