:root {
  --ink: #1b2735;
  --ink-strong: #0d1522;
  --muted: #586574;
  --accent: #2157d6;
  --accent-light: #7bc7ff;
  --line: #d8e2ee;
  --bg: linear-gradient(180deg, #f8fbff 0%, #f3f6fb 55%, #eef3fa 100%);
  --surface: #ffffff;
  --surface-soft: #eef5fb;
  --shadow: 0 22px 50px rgba(20, 40, 70, 0.12);
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Noto Sans JP", sans-serif;
  color: var(--ink);
  background: var(--bg);
}

img {
  max-width: 100%;
  display: block;
}

a {
  color: inherit;
}

.container {
  width: min(1160px, 90vw);
  margin: 0 auto;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 8px 22px;
  border-radius: 12px;
  border: 1px solid var(--accent);
  background: var(--accent);
  color: #fff;
  text-decoration: none;
  font-weight: 600;
  line-height: 1;
  font-size: 14px;
  box-shadow: none;
}

.button.secondary {
  background: transparent;
  color: var(--accent);
  border-color: var(--accent);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.9);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(13, 41, 78, 0.08);
  box-shadow: none;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
}

.brand-mark {
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: #fff;
  background-image: url("../img/bflogo.png");
  background-size: cover;
  background-position: center;
  color: transparent;
  display: grid;
  place-items: center;
  font-weight: 700;
  letter-spacing: 0.5px;
  box-shadow: none;
}

.brand-text {
  display: grid;
  gap: 2px;
}

.brand-text strong {
  font-size: 15px;
  letter-spacing: 1px;
  font-family: "Barlow Condensed", sans-serif;
}

.brand-text span {
  font-size: 11px;
  color: var(--muted);
}

.site-nav {
  display: flex;
  gap: 18px;
  flex-wrap: wrap;
  align-items: center;
  font-size: 13px;
  letter-spacing: 0.8px;
}

.site-nav a {
  text-decoration: none;
  color: var(--muted);
  padding-bottom: 2px;
  border-bottom: 1px solid transparent;
}

.site-nav a[aria-current="page"] {
  color: var(--ink-strong);
  border-color: var(--accent);
}

.header-cta {
  text-decoration: none;
  padding: 10px 18px;
  border-radius: 999px;
  background: var(--accent);
  color: #fff;
  font-size: 12px;
  letter-spacing: 1px;
  box-shadow: none;
}

.site-footer {
  border-top: 1px solid rgba(13, 41, 78, 0.08);
  padding: 32px 0 48px;
  background: #fff;
  box-shadow: none;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  color: var(--muted);
  font-size: 12px;
}

.footer-inner strong {
  color: var(--ink-strong);
  font-weight: 600;
}

@media (max-width: 900px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
  }
}

@media (max-width: 640px) {
  .header-cta {
    width: 100%;
    text-align: center;
  }

  .site-nav {
    width: 100%;
  }
}