/* ベースカラーと変数の定義（既存画面と統一） */
:root {
  --primary-color: #2563eb;
  --primary-hover: #1d4ed8;
  --bg-color: #f3f4f6;
  --card-bg: #ffffff;
  --text-main: #111827;
  --text-sub: #4b5563;
  --text-light: #9ca3af;
  --border-color: #e5e7eb;
  --error-bg: #fef2f2;
  --error-text: #b91c1c;
  --error-border: #f87171;
  --success-bg: #f0fdf4;
  --success-text: #15803d;
  --success-border: #86efac;
}

body {
  margin: 0;
  padding: 0;
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-main);
  -webkit-font-smoothing: antialiased;
  background:
    linear-gradient(180deg,
      #f8fafc 0%,
      #eef2ff 100%);
}

/* ページ全体レイアウト */
.auth-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  padding: 24px;
  box-sizing: border-box;
}

/* 中央1カラム用のカードスタイル */
.auth-card-single {
  background: var(--card-bg);
  border-radius: 16px;
  box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
  width: 100%;
  max-width: 480px;
  padding: 48px 40px;
  box-sizing: border-box;
}

/* ヘッダー・ロゴ周り */
.auth-header {
  text-align: center;
  margin-bottom: 32px;
}

.auth-logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin-bottom: 24px;
  text-decoration: none;
}

.auth-logo-icon {
  width: 32px;
  height: 32px;
  background-color: var(--primary-color);
  color: white;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 1.25rem;
}

.auth-logo-text {
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--text-main);
}

.auth-logo-sub {
  font-weight: 400;
  color: var(--text-sub);
  font-size: 0.875rem;
}

.auth-title {
  margin: 0 0 12px 0;
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-main);
}

.auth-subtitle {
  margin: 0;
  color: var(--text-sub);
  font-size: 0.95rem;
  line-height: 1.5;
}

/* Flashメッセージ（アラート） */
.alert {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 12px 16px;
  border-radius: 8px;
  margin-bottom: 24px;
  font-size: 0.875rem;
  font-weight: 500;
  line-height: 1.4;
}

.alert svg {
  flex-shrink: 0;
  margin-top: 2px;
}

.alert-error {
  background-color: var(--error-bg);
  color: var(--error-text);
  border: 1px solid var(--error-border);
}

.alert-success {
  background-color: var(--success-bg);
  color: var(--success-text);
  border: 1px solid var(--success-border);
}

/* フォーム要素 */
.auth-form {
  margin-bottom: 24px;
}

.form-group {
  margin-bottom: 24px;
}

.form-label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
  margin-bottom: 8px;
}

.form-input {
  width: 100%;
  padding: 14px 16px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 1rem;
  box-sizing: border-box;
  transition: all 0.2s;
  color: var(--text-main);
  background-color: #fafafa;
}

.form-input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
  background-color: #ffffff;
}

.form-input::placeholder {
  color: var(--text-light);
}

/* ボタン */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 24px;
  font-size: 1rem;
  font-weight: 600;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: background-color 0.2s;
  width: 100%;
  box-sizing: border-box;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
}

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

/* セキュリティ注意文 */
.security-note {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-top: 16px;
  font-size: 0.8rem;
  color: var(--text-light);
  line-height: 1.5;
}

.security-note svg {
  flex-shrink: 0;
  color: var(--text-light);
}

/* フッター（戻るリンク） */
.auth-footer {
  text-align: center;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--border-color);
}

.back-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  color: var(--text-sub);
  text-decoration: none;
  font-size: 0.9rem;
  font-weight: 500;
  transition: color 0.2s;
}

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

/* レスポンシブ対応 */
@media (max-width: 480px) {
  .auth-wrapper {
    padding: 16px;
  }

  .auth-card-single {
    padding: 32px 24px;
  }

  .auth-title {
    font-size: 1.25rem;
  }
}


.alert span {
  white-space: pre-line;
}

.auth-logo {
  text-decoration: none;
  color: inherit;
}