:root {
  color-scheme: light dark;
  --bg: #ffffff;
  --fg: #1a1a1a;
  --muted: #666;
  --border: #ddd;
  --accent: #2563eb;
  --accent-fg: #ffffff;
  --danger: #dc2626;
  --ok: #16a34a;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111213;
    --fg: #eaeaea;
    --muted: #999;
    --border: #333;
  }
}

* { box-sizing: border-box; }

html, body {
  height: 100%;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--fg);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.card {
  width: 100%;
  max-width: 380px;
  text-align: center;
}

.logo-frame {
  display: inline-block;
  background: #ffffff;
  padding: 20px 28px;
  border-radius: 12px;
  margin-bottom: 40px;
}

.logo {
  max-width: 260px;
  width: 100%;
  height: auto;
  display: block;
}

.login-btn {
  display: block;
  width: 100%;
  padding: 12px 20px;
  background: var(--accent);
  color: var(--accent-fg);
  text-decoration: none;
  font-weight: 600;
  font-size: 1rem;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  font-family: inherit;
  text-align: center;
  transition: opacity 0.15s ease;
}
.login-btn:hover {
  opacity: 0.9;
}
.login-btn + .login-btn {
  margin-top: 12px;
}
.login-btn.secondary {
  background: transparent;
  color: var(--fg);
  border: 1px solid var(--border);
}

/* Modal */
.modal-backdrop {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  align-items: center;
  justify-content: center;
  padding: 24px;
  z-index: 10;
}
.modal-backdrop.open {
  display: flex;
}
.modal {
  position: relative;
  width: 100%;
  max-width: 420px;
  max-height: 90vh;
  overflow-y: auto;
  background: var(--bg);
  color: var(--fg);
  border-radius: 12px;
  padding: 28px;
  border: 1px solid var(--border);
}
.modal h2 {
  margin-top: 0;
}
.modal-close {
  position: absolute;
  top: 16px;
  right: 16px;
  background: none;
  border: none;
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  color: var(--muted);
  padding: 0;
  width: auto;
}

.modal label {
  display: block;
  font-size: 0.85rem;
  margin: 12px 0 4px;
  color: var(--muted);
  text-align: left;
}
.modal input,
.modal textarea {
  width: 100%;
  font: inherit;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--bg);
  color: var(--fg);
}
.modal textarea {
  resize: vertical;
}
.modal .radio-row {
  display: flex;
  gap: 16px;
}
.modal .radio-row label {
  display: flex;
  align-items: center;
  gap: 6px;
  margin: 0;
  color: var(--fg);
}
.modal .radio-row input {
  width: auto;
}
.modal button[type="submit"] {
  width: 100%;
  padding: 12px 20px;
  background: var(--accent);
  color: var(--accent-fg);
  border: none;
  border-radius: 8px;
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
}
.modal button[type="submit"]:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.hp-field {
  position: absolute;
  left: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

#register-message {
  margin-top: 12px;
  font-size: 0.9rem;
  text-align: left;
}
#register-message.success {
  color: var(--ok);
}
#register-message.error {
  color: var(--danger);
}