@charset "UTF-8";

:root {
  --projects-bg: #eef3f8;
  --projects-surface: #ffffff;
  --projects-border: #d6dee8;
  --projects-text: #28405f;
  --projects-heading: #143f69;
  --projects-accent: #c63b2d;
  --projects-shadow: 0 8px 24px rgba(20, 63, 105, 0.06);
  --projects-radius: 14px;
}

html {
  scroll-behavior: smooth;
}

.projects-page {
  background: var(--projects-bg);
  color: var(--projects-text);
}

.projects-page .container {
  width: min(1100px, calc(100% - 40px));
  margin-inline: auto;
}

/* =========================
   パンくず
========================= */

.projects-breadcrumb {
  padding: 18px 0 0;
}

.projects-breadcrumb-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
  color: #5f7894;
  font-size: 0.95rem;
}

.projects-breadcrumb-list a {
  color: #315f97;
  text-decoration: none;
}

.projects-breadcrumb-list a:hover {
  text-decoration: underline;
}

/* =========================
   ページ見出し
========================= */

.projects-hero {
  padding: 24px 0 32px;
  background: linear-gradient(180deg, #edf3f8 0%, #e8eff6 100%);
  border-bottom: 1px solid #d9e2ec;
}

.projects-kicker {
  margin: 0 0 10px;
  color: var(--projects-accent);
  font-size: 0.92rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.projects-title {
  margin: 0;
  font-size: clamp(2rem, 3vw, 3rem);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: 0.02em;
  color: var(--projects-heading);
}

.projects-lead {
  max-width: 920px;
  margin: 18px 0 0;
  font-size: 1.02rem;
  line-height: 2;
  color: #47617f;
}

/* =========================
   セクション
========================= */

.projects-section {
  padding: 22px 0 34px;
}

.projects-card {
  background: var(--projects-surface);
  border: 1px solid var(--projects-border);
  border-radius: var(--projects-radius);
  box-shadow: var(--projects-shadow);
  padding: 36px 40px;
}

.projects-section-title {
  position: relative;
  margin: 0 0 24px;
  padding-left: 18px;
  font-size: clamp(1.45rem, 2vw, 2rem);
  line-height: 1.3;
  font-weight: 800;
  color: var(--projects-heading);
}

.projects-section-title::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.15em;
  width: 6px;
  height: 1.2em;
  border-radius: 999px;
  background: var(--projects-heading);
}

/* =========================
   研究テーマ階層
========================= */

.research-tree {
  list-style: none;
  padding-left: 0;
  margin: 28px 0 0;
  line-height: 1.9;
}

.research-tree > li {
  margin-bottom: 30px;
}

.research-tree > li:last-child {
  margin-bottom: 0;
}

.research-group {
  display: block;
  position: relative;
  padding-left: 18px;
  font-weight: 700;
  font-size: 1.08rem;
  color: var(--projects-heading);
}

.research-group::before {
  content: "■";
  position: absolute;
  left: 0;
  top: 0;
  color: #1e5aa8;
  font-size: 0.9rem;
}

.research-tree ul {
  list-style: none;
  margin: 10px 0 0;
  padding-left: 30px;
}

.research-tree ul li {
  margin: 6px 0;
  color: #526b84;
  font-size: 1rem;
  line-height: 1.9;
}

/* =========================
   レスポンシブ
========================= */

@media (max-width: 767px) {
  .projects-hero {
    padding: 22px 0 26px;
  }

  .projects-title {
    font-size: clamp(1.85rem, 7vw, 2.5rem);
  }

  .projects-card {
    padding: 24px 20px;
  }

  .projects-lead,
  .research-tree ul li {
    line-height: 1.9;
  }

  .research-tree ul {
    padding-left: 22px;
  }
}