/* ============================================
   課題提起セクション (F-003)
   株式会社PHOSS コーポレートサイト
   ============================================ */

/* ----------------------------------------
   セクションベース
   ---------------------------------------- */
.problems {
  background-color: var(--bg-subtle);
  padding-block: var(--space-24);
  position: relative;
  overflow: hidden;
}

/* 背景装飾（右上・左下にうっすらアクセント） */
.problems::before {
  content: '';
  position: absolute;
  top: -80px;
  right: -80px;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(0, 144, 232, 0.05) 0%,
    transparent 70%
  );
  pointer-events: none;
}

.problems::after {
  content: '';
  position: absolute;
  bottom: -60px;
  left: -60px;
  width: 240px;
  height: 240px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(30, 64, 128, 0.06) 0%,
    transparent 70%
  );
  pointer-events: none;
}

/* ----------------------------------------
   セクションヘッダー
   ---------------------------------------- */
.problems__header {
  text-align: center;
  margin-bottom: var(--space-12);
}

.problems__label {
  display: inline-block;
  font-size: var(--font-size-sm);
  font-weight: var(--font-weight-semibold);
  letter-spacing: var(--letter-spacing-widest);
  text-transform: uppercase;
  color: var(--color-accent-500);
  margin-bottom: var(--space-3);
}

.problems__title {
  font-size: clamp(var(--font-size-xl), 3.5vw, var(--font-size-3xl));
  font-weight: var(--font-weight-bold);
  color: var(--text-primary);
  line-height: var(--line-height-snug);
  margin-bottom: var(--space-4);
}

.problems__divider {
  width: 60px;
  height: 4px;
  background: linear-gradient(
    90deg,
    var(--color-accent-500),
    var(--color-primary-300)
  );
  border-radius: var(--radius-full);
  margin-inline: auto;
}

/* ----------------------------------------
   課題カードグリッド
   ---------------------------------------- */
.problems__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  margin-bottom: var(--space-12);
}

/* ----------------------------------------
   課題カード
   ---------------------------------------- */
.problem-card {
  background-color: var(--color-white);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-color-base);
  padding: var(--space-6) var(--space-8);
  display: flex;
  align-items: flex-start;
  gap: var(--space-4);
  box-shadow: var(--shadow-sm);
  transition:
    box-shadow var(--transition-base),
    transform var(--transition-base),
    border-color var(--transition-base),
    background-color var(--transition-base);
  cursor: default;

  /* スクロールアニメーション初期状態 */
  opacity: 0;
  transform: translateY(20px);
}

/* data-animate が付与され、is-animated が加わったら表示 */
.problem-card.is-animated {
  opacity: 1;
  transform: translateY(0);
  transition:
    opacity 0.55s ease,
    transform 0.55s ease,
    box-shadow var(--transition-base),
    border-color var(--transition-base),
    background-color var(--transition-base);
}

/* ホバー効果 */
.problem-card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-4px);
  border-color: var(--color-primary-200);
  background-color: var(--color-white);
}

/* アニメーション済み状態でのホバー */
.problem-card.is-animated:hover {
  transform: translateY(-4px);
}

/* ----------------------------------------
   課題カード: アイコン部分
   ---------------------------------------- */
.problem-card__icon {
  flex-shrink: 0;
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: linear-gradient(
    135deg,
    var(--color-primary-50) 0%,
    rgba(0, 144, 232, 0.08) 100%
  );
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition-base);
}

.problem-card__icon svg {
  width: 22px;
  height: 22px;
  color: var(--color-accent-500);
  flex-shrink: 0;
}

.problem-card:hover .problem-card__icon {
  background: linear-gradient(
    135deg,
    rgba(0, 144, 232, 0.12) 0%,
    rgba(0, 144, 232, 0.20) 100%
  );
}

/* ----------------------------------------
   課題カード: テキスト部分
   ---------------------------------------- */
.problem-card__body {
  flex: 1;
  min-width: 0;
}

.problem-card__text {
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  color: var(--text-primary);
  line-height: var(--line-height-relaxed);
  margin: 0;
}

/* ----------------------------------------
   結論エリア（解決宣言 + CTA）
   ---------------------------------------- */
.problems__conclusion {
  text-align: center;
  padding: var(--space-10) var(--space-8);
  background: linear-gradient(
    135deg,
    var(--color-primary-800) 0%,
    var(--color-primary-700) 50%,
    #1a3668 100%
  );
  border-radius: var(--radius-2xl);
  position: relative;
  overflow: hidden;
}

/* 結論エリア背景装飾 */
.problems__conclusion::before {
  content: '';
  position: absolute;
  top: -40px;
  right: -40px;
  width: 200px;
  height: 200px;
  border-radius: 50%;
  border: 1px solid rgba(0, 144, 232, 0.2);
  pointer-events: none;
}

.problems__conclusion::after {
  content: '';
  position: absolute;
  bottom: -30px;
  left: -30px;
  width: 150px;
  height: 150px;
  border-radius: 50%;
  border: 1px solid rgba(41, 168, 245, 0.15);
  pointer-events: none;
}

.problems__conclusion-text {
  font-size: clamp(var(--font-size-lg), 3vw, var(--font-size-2xl));
  font-weight: var(--font-weight-bold);
  color: var(--color-white);
  margin-bottom: var(--space-3);
  position: relative;
  z-index: 1;
}

.problems__conclusion-text em {
  font-style: normal;
  color: var(--color-accent-300);
}

.problems__conclusion-sub {
  font-size: var(--font-size-base);
  color: rgba(255, 255, 255, 0.70);
  margin-bottom: var(--space-8);
  line-height: var(--line-height-relaxed);
  position: relative;
  z-index: 1;
}

.problems__conclusion-actions {
  display: flex;
  gap: var(--space-4);
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
  z-index: 1;
}

/* ----------------------------------------
   アニメーション遅延（カードを順番に出現）
   ---------------------------------------- */
.problem-card:nth-child(1) { transition-delay: 0.05s; }
.problem-card:nth-child(2) { transition-delay: 0.10s; }
.problem-card:nth-child(3) { transition-delay: 0.15s; }
.problem-card:nth-child(4) { transition-delay: 0.20s; }
.problem-card:nth-child(5) { transition-delay: 0.25s; }
.problem-card:nth-child(6) { transition-delay: 0.30s; }

/* is-animated 適用後の delay はトランジションで使うため維持 */
.problem-card.is-animated:nth-child(1) { transition-delay: 0.05s; }
.problem-card.is-animated:nth-child(2) { transition-delay: 0.10s; }
.problem-card.is-animated:nth-child(3) { transition-delay: 0.15s; }
.problem-card.is-animated:nth-child(4) { transition-delay: 0.20s; }
.problem-card.is-animated:nth-child(5) { transition-delay: 0.25s; }
.problem-card.is-animated:nth-child(6) { transition-delay: 0.30s; }

/* ----------------------------------------
   prefers-reduced-motion
   ---------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  .problem-card {
    opacity: 1;
    transform: none;
    transition: box-shadow var(--transition-base),
                border-color var(--transition-base);
  }

  .problem-card.is-animated {
    transition: box-shadow var(--transition-base),
                border-color var(--transition-base);
  }

  .problem-card:hover {
    transform: none;
  }
}

/* ----------------------------------------
   レスポンシブ: タブレット（768px〜1023px）
   ---------------------------------------- */
@media (min-width: 768px) and (max-width: 1023px) {
  .problems {
    padding-block: var(--space-16);
  }

  .problems__grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-5);
  }

  .problems__title {
    font-size: var(--font-size-2xl);
  }
}

/* ----------------------------------------
   レスポンシブ: スマートフォン（〜767px）
   ---------------------------------------- */
@media (max-width: 767px) {
  .problems {
    padding-block: var(--space-12);
  }

  .problems__title {
    font-size: var(--font-size-xl);
  }

  .problems__grid {
    grid-template-columns: 1fr;
    gap: var(--space-4);
    margin-bottom: var(--space-8);
  }

  .problem-card {
    padding: var(--space-5) var(--space-6);
  }

  .problem-card__icon {
    width: 40px;
    height: 40px;
  }

  .problem-card__icon svg {
    width: 20px;
    height: 20px;
  }

  .problem-card__text {
    font-size: var(--font-size-sm);
  }

  .problems__conclusion {
    padding: var(--space-8) var(--space-6);
    border-radius: var(--radius-xl);
  }

  .problems__conclusion-text {
    font-size: var(--font-size-lg);
  }

  .problems__conclusion-actions {
    flex-direction: column;
    align-items: center;
  }

  .problems__conclusion-actions .btn--lg {
    width: 100%;
    max-width: 320px;
    justify-content: center;
  }
}