:root {
  --ppf-bg:            #F7F5F2;
  --ppf-card-bg:       #FFFFFF;
  --ppf-border:        rgba(62, 79, 99, 0.10);
  --ppf-border-hover:  rgba(62, 79, 99, 0.25);
  --ppf-text-primary:  #3E4F63;
  --ppf-text-muted:    #7A7872;
  --ppf-accent:        #3E4F63;
  --ppf-input-bg:      #FAFAF8;
  --ppf-shadow:        0 2px 24px rgba(62, 79, 99, 0.06), 0 1px 4px rgba(0, 0, 0, 0.04);
  --ppf-transition:    0.22s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================================
   フォーム本体
   ============================================================ */
.post-password-form {
  background: var(--ppf-card-bg);
  border: 1px solid var(--ppf-border);
  border-radius: 16px;
  box-shadow: var(--ppf-shadow);
  padding: 3rem 2.5rem 2.5rem;
  max-width: 420px;
  width: 100%;
  margin: 10rem auto 0 auto;
  position: relative;
  overflow: hidden;
  box-sizing: border-box;
}

/* 上部アクセントライン */
.post-password-form::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 2px;
  background: var(--ppf-accent);
}

/* ロックアイコン */
.post-password-form::after {
  content: '🔒';
  display: block;
  font-size: 1.75rem;
  text-align: center;
  margin: 1.25rem 0;
  filter: grayscale(1) opacity(0.5);
}

/* ============================================================
   説明文 (1つ目の <p>)
   ============================================================ */
.post-password-form > p:first-of-type {
  font-size: 1.1rem;
  font-weight: 300;
  color: var(--ppf-text-muted);
  margin: 0 0 2rem;
  line-height: 1.7;
}

/* ============================================================
   入力行 (2つ目の <p> — label + submit を含む)
   ============================================================ */
.post-password-form > p:last-of-type {
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 0;
}

/* ============================================================
   <label> — "パスワード:" テキスト + input を内包
   ============================================================ */
.post-password-form label {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ppf-text-muted);
  margin-bottom: 0;
}

/* ============================================================
   パスワード入力フィールド
   ============================================================ */
.post-password-form input[type="password"] {
  display: block;
  width: 100%;
  height: 48px;
  padding: 0 1rem;
  box-sizing: border-box;
  font-size: 0.9375rem;
  font-weight: 300;
  letter-spacing: 0.05em;
  color: var(--ppf-text-primary);
  background: var(--ppf-input-bg);
  border: 1px solid var(--ppf-border);
  border-radius: 8px;
  outline: none;
  transition: border-color var(--ppf-transition),
  box-shadow var(--ppf-transition),
  background var(--ppf-transition);
  -webkit-appearance: none;
  appearance: none;
  min-width: 0;
}

.post-password-form input[type="password"]::placeholder {
  color: #C0BDB8;
  font-weight: 300;
}

.post-password-form input[type="password"]:hover {
  border-color: var(--ppf-border-hover);
}

.post-password-form input[type="password"]:focus {
  border-color: var(--ppf-accent);
  background: #FFFFFF;
  box-shadow: 0 0 0 3px rgba(44, 44, 42, 0.08);
}

/* ============================================================
   送信ボタン
   ============================================================ */
.post-password-form input[type="submit"] {
  display: block;
  width: 100%;
  height: 48px;
  margin-top: 1rem;
  padding: 0 1.5rem;
  font-size: 0.875rem;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  text-align: center;
  color: #FFFFFF;
  background: var(--ppf-accent);
  border: none;
  border-radius: 8px;
  cursor: pointer;
  outline: none;
  transition: background var(--ppf-transition),
  transform var(--ppf-transition),
  box-shadow var(--ppf-transition);
  -webkit-appearance: none;
  appearance: none;
}

.post-password-form input[type="submit"]:hover {
  background: #3E3E3C;
  box-shadow: 0 4px 12px rgba(44, 44, 42, 0.22);
}

.post-password-form input[type="submit"]:active {
  transform: scale(0.98);
  box-shadow: none;
}

.post-password-form input[type="submit"]:focus-visible {
  box-shadow: 0 0 0 3px rgba(44, 44, 42, 0.3);
}

/* ============================================================
   レスポンシブ
   ============================================================ */
@media (max-width: 480px) {
  .post-password-form {
    padding: 2.25rem 1.5rem 2rem;
    border-radius: 8px;
    margin: 1rem auto;
  }
}