* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: #111513;
  color: #d9dfdc;
  font-family:
    -apple-system,
    BlinkMacSystemFont,
    "Hiragino Kaku Gothic ProN",
    "Yu Gothic",
    Meiryo,
    sans-serif;
  line-height: 1.8;
}

a {
  color: inherit;
}

.container {
  width: min(1100px, calc(100% - 40px));
  margin: 0 auto;
}


/* =====================
   Header
===================== */

.header {
  position: sticky;
  top: 0;
  z-index: 100;

  background: rgba(17, 21, 19, 0.95);
  border-bottom: 1px solid #313835;
  backdrop-filter: blur(10px);
}

.header-inner {
  min-height: 70px;

  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: Georgia, "Times New Roman", serif;
  font-size: 15px;
  letter-spacing: 0.15em;

  color: #d9dfdc;
  text-decoration: none;
}

.nav {
  display: flex;
  gap: 28px;
}

.nav a {
  color: #929d98;
  font-size: 12px;
  letter-spacing: 0.15em;
  text-decoration: none;

  transition: color 0.2s ease;
}

.nav a:hover {
  color: #ffffff;
}


/* =====================
   Hero
===================== */

.hero {
  padding: 110px 0 90px;

  border-bottom: 1px solid #313835;

  background:
    linear-gradient(
      rgba(17, 21, 19, 0.88),
      rgba(17, 21, 19, 0.96)
    ),
    repeating-linear-gradient(
      0deg,
      transparent,
      transparent 3px,
      rgba(255,255,255,0.015) 4px
    );
}

.hero-label {
  margin: 0 0 15px;

  color: #78847e;

  font-family: monospace;
  font-size: 12px;
  letter-spacing: 0.2em;
}

.hero h1 {
  margin: 0;

  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(45px, 8vw, 80px);
  font-weight: normal;
  letter-spacing: 0.08em;

  color: #edf1ef;
}

.hero-description {
  max-width: 620px;

  margin-top: 30px;

  color: #9ba5a0;
  font-size: 14px;
}


/* =====================
   Notice
===================== */

.notice {
  padding: 30px 0;

  background: #191f1c;
  border-bottom: 1px solid #313835;
}

.notice .container {
  display: flex;
  align-items: flex-start;
  gap: 30px;
}

.notice-label {
  flex-shrink: 0;

  margin: 0;

  color: #b6aa75;

  font-family: monospace;
  font-size: 11px;
  letter-spacing: 0.18em;
}

.notice p:last-child {
  margin: 0;

  color: #8e9893;
  font-size: 13px;
}


/* =====================
   Archive
===================== */

.archive {
  padding: 90px 0 120px;
}

.section-heading {
  margin-bottom: 45px;
}

.section-heading p {
  margin: 0 0 8px;

  color: #69746f;

  font-family: monospace;
  font-size: 11px;
  letter-spacing: 0.2em;
}

.section-heading h2 {
  margin: 0;

  color: #e4e9e6;

  font-family: Georgia, "Times New Roman", serif;
  font-size: 34px;
  font-weight: normal;
}


/* =====================
   Research Card
===================== */

.research-list {
  border-top: 1px solid #333b37;
}

.research-card {
  display: grid;

  grid-template-columns: 150px 1fr;

  border-bottom: 1px solid #333b37;

  transition: background 0.2s ease;
}

.research-card:hover {
  background: #161b18;
}

.research-number {
  padding: 35px 25px;

  border-right: 1px solid #333b37;

  color: #606b66;

  font-family: monospace;
  font-size: 12px;
  letter-spacing: 0.12em;
}

.research-content {
  padding: 35px 40px;
}

.research-top {
  display: flex;
  justify-content: space-between;
  align-items: center;

  gap: 20px;

  margin-bottom: 25px;
}

.research-top h3 {
  margin: 0;

  color: #dfe5e2;

  font-family: Georgia, "Times New Roman", serif;
  font-size: 24px;
  font-weight: normal;
}


/* =====================
   Status
===================== */

.status {
  flex-shrink: 0;

  padding: 5px 10px;

  border: 1px solid;

  font-family: monospace;
  font-size: 10px;
  letter-spacing: 0.1em;
}

.investigation {
  color: #c0a96b;
  border-color: #645936;
}

.observation {
  color: #8da99b;
  border-color: #40574c;
}

.restricted {
  color: #be7272;
  border-color: #673c3c;
}

.complete {
  color: #89958f;
  border-color: #4c5752;
}


/* =====================
   Data
===================== */

.research-data {
  display: grid;

  grid-template-columns: repeat(4, 1fr);

  margin: 0 0 25px;

  border-top: 1px solid #2d3531;
  border-bottom: 1px solid #2d3531;
}

.research-data div {
  padding: 15px;

  border-right: 1px solid #2d3531;
}

.research-data div:last-child {
  border-right: none;
}

.research-data dt {
  margin-bottom: 5px;

  color: #69736e;

  font-family: monospace;
  font-size: 10px;
}

.research-data dd {
  margin: 0;

  color: #b8c0bc;

  font-size: 12px;
}


/* =====================
   Description
===================== */

.research-text {
  max-width: 760px;

  margin: 0;

  color: #8e9993;

  font-size: 13px;
}

.classified {
  display: inline-block;

  margin-top: 25px;
  padding: 8px 14px;

  color: #a85f5f;

  border: 1px solid #613737;

  font-family: monospace;
  font-size: 10px;
  letter-spacing: 0.15em;
}


/* =====================
   Footer
===================== */

.footer {
  padding: 35px 0;

  border-top: 1px solid #313835;
}

.footer-inner {
  display: flex;
  justify-content: space-between;

  color: #59645f;

  font-family: monospace;
  font-size: 10px;
  letter-spacing: 0.1em;
}

.footer p {
  margin: 0;
}


/* =====================
   Smartphone
===================== */

@media (max-width: 750px) {

  .header-inner {
    flex-direction: column;
    justify-content: center;

    padding: 18px 0;

    gap: 12px;
  }

  .nav {
    gap: 18px;
  }

  .hero {
    padding: 70px 0 60px;
  }

  .notice .container {
    flex-direction: column;
    gap: 10px;
  }

  .archive {
    padding: 60px 0 80px;
  }

  .research-card {
    grid-template-columns: 1fr;
  }

  .research-number {
    padding: 15px 20px;

    border-right: none;
    border-bottom: 1px solid #333b37;
  }

  .research-content {
    padding: 25px 20px 35px;
  }

  .research-top {
    align-items: flex-start;
  }

  .research-data {
    grid-template-columns: repeat(2, 1fr);
  }

  .research-data div {
    border-bottom: 1px solid #2d3531;
  }

  .footer-inner {
    flex-direction: column;
    gap: 8px;
  }

}