:root {
  --bg: #050505;
  --paper: #111111;
  --ink: #f7f5ef;
  --muted: #b8b1a3;
  --line: #3a352c;
  --soft: #171511;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.32);
}

* {
  box-sizing: border-box;
}

html {
  color: var(--ink);
  background: var(--bg);
  font-family: "Kosugi", "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  line-height: 1.8;
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  min-width: 320px;
}

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

.sp_only {
  display: none;
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.22em;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px clamp(18px, 4vw, 56px);
  border-bottom: 1px solid var(--line);
  background: rgba(5, 5, 5, 0.9);
  backdrop-filter: blur(12px);
}

.brand {
  font-family: "Roboto Slab", Georgia, "Times New Roman", serif;
  font-size: 18px;
  letter-spacing: 0;
  text-decoration: none;
  white-space: nowrap;
}

.nav-toggle,
.nav-toggle-label {
  display: none;
}

.site-nav,
.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  align-items: center;
  color: var(--muted);
  font-size: 13px;
}

.site-nav a,
.footer-nav a {
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current="page"],
.footer-nav a:hover {
  color: var(--ink);
}

.hero {
  position: relative;
  min-height: calc(100vh - 74px);
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  align-items: end;
  padding: clamp(70px, 11vw, 138px) clamp(18px, 5vw, 72px) clamp(44px, 7vw, 86px);
  border-bottom: 1px solid var(--line);
  overflow: hidden;
  isolation: isolate;
}

.hero::before {
  position: absolute;
  inset: 0;
  z-index: -2;
  content: "";
  background: url("./img/mv.jpg") center / cover no-repeat;
}

.hero::after {
  position: absolute;
  inset: 0;
  z-index: -1;
  content: "";
  background:
    linear-gradient(90deg, rgba(5, 5, 5, 0.88), rgba(5, 5, 5, 0.62) 48%, rgba(5, 5, 5, 0.82)),
    rgba(5, 5, 5, 0.28);
}

.hero-copy {
  max-width: 980px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--muted);
  font-family: "Roboto Slab", Georgia, "Times New Roman", serif;
  font-size: 15px;
  letter-spacing: 0.14em;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  line-height: 1.18;
  font-weight: 500;
  letter-spacing: 0;
}

h1 {
  font-weight: 400;
}

.hero h1 {
  margin-bottom: 24px;
  font-family: "Roboto Slab", Georgia, "Times New Roman", serif;
  font-size: clamp(60px, 13vw, 190px);
  line-height: 0.92;
}

.lead {
  margin-top: clamp(34px, 6vw, 84px);
  max-width: 760px;
  color: #e1dbcf;
  font-size: clamp(16px, 2vw, 21px);
}

.section,
.page-main {
  padding-inline: clamp(18px, 5vw, 72px);
}

.section {
  padding-top: clamp(64px, 9vw, 116px);
  padding-bottom: clamp(64px, 9vw, 116px);
  border-bottom: 1px solid var(--line);
}

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 32px;
}

.section-heading h2,
.page-hero h1 {
  margin-bottom: 0;
  font-family: "Kosugi", "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  font-size: clamp(36px, 5vw, 72px);
}

.section-heading h2 {
  font-size: 30px;
}

.section-title-small {
  font-family: "Kosugi", "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", Meiryo, sans-serif;
  font-size: 30px;
  font-weight: 500;
}

.tool-card {
  display: grid;
  grid-template-columns: minmax(220px, 360px) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 64px);
  align-items: stretch;
  padding: clamp(18px, 3vw, 34px);
  border: 1px solid var(--line);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.tool-card + .tool-card {
  margin-top: 24px;
}

.tool-thumb {
  display: block;
  aspect-ratio: 1 / 1;
  overflow: hidden;
  border: 1px solid var(--ink);
  background: var(--soft);
}

.tool-thumb img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 180ms ease;
}

.tool-thumb:hover img {
  transform: scale(1.03);
}

.tool-body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  max-width: 780px;
}

.tool-label {
  margin-bottom: 10px;
  color: var(--muted);
  font-size: 13px;
}

.tool-body h3 {
  margin-bottom: 18px;
  font-size: clamp(28px, 4vw, 48px);
}

.tool-body .tool-title-long {
  font-size: clamp(24px, 3vw, 38px);
  line-height: 1.35;
}

.small-note {
  color: var(--muted);
  font-size: 14px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: fit-content;
  min-height: 46px;
  margin-top: 12px;
  padding: 10px 18px;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--bg);
  font-size: 14px;
  text-decoration: none;
  transition: background 160ms ease, color 160ms ease;
}

.button:hover {
  background: transparent;
  color: var(--ink);
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 12px;
}

.button-ghost {
  background: transparent;
  color: var(--ink);
}

.button-ghost:hover {
  background: var(--ink);
  color: var(--bg);
}

.split-section {
  display: grid;
  grid-template-columns: minmax(220px, 0.45fr) minmax(0, 1fr);
  gap: clamp(28px, 6vw, 90px);
}

.split-section .section-heading {
  display: block;
  margin-bottom: 0;
}

.text-columns {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: clamp(24px, 4vw, 56px);
  color: #d8d2c4;
}

.notice {
  display: grid;
  grid-template-columns: minmax(220px, 0.45fr) minmax(0, 1fr);
  gap: clamp(28px, 6vw, 90px);
  background: var(--soft);
}

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

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 30px clamp(18px, 5vw, 72px);
  background: #0b0b0b;
  color: var(--ink);
}

.site-footer .footer-nav,
.copyright {
  color: rgba(247, 245, 239, 0.72);
}

.copyright {
  margin: 0;
  font-family: "Roboto Slab", Georgia, "Times New Roman", serif;
  font-size: 13px;
}

.page-main {
  padding-top: clamp(56px, 9vw, 110px);
  padding-bottom: clamp(70px, 10vw, 130px);
}

.page-hero {
  max-width: 920px;
  margin-bottom: clamp(36px, 7vw, 82px);
}

.page-hero p:not(.eyebrow) {
  max-width: 760px;
  margin-top: 2em;
  color: var(--muted);
  font-size: 17px;
}

.app-guide-thumb {
  max-width: 360px;
  margin: 28px 0 0;
  border: 1px solid var(--ink);
  background: var(--soft);
}

.app-guide-thumb img {
  width: 100%;
  height: auto;
}

.content-block {
  max-width: 920px;
  padding: clamp(22px, 4vw, 44px);
  border-top: 1px solid var(--ink);
  border-bottom: 1px solid var(--line);
  background: rgba(17, 17, 17, 0.72);
}

.content-block h2 {
  margin: 42px 0 12px;
  font-size: clamp(22px, 2.5vw, 30px);
}

.content-block h3 {
  margin: 38px 0 10px;
  font-size: clamp(18px, 2vw, 24px);
}

.content-block h2:first-child {
  margin-top: 0;
}

.content-block h3:first-child {
  margin-top: 0;
}

.content-block p {
  color: #d8d2c4;
}

.content-block ul {
  margin: 0 0 24px;
  padding-left: 1.4em;
  color: #d8d2c4;
}

.content-block li + li {
  margin-top: 8px;
}

.compact-section {
  background: #0b0b0b;
}

.info-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(14px, 2vw, 22px);
}

.info-link {
  display: grid;
  min-height: 168px;
  align-content: space-between;
  gap: 22px;
  padding: clamp(18px, 3vw, 28px);
  border: 1px solid var(--line);
  background: rgba(247, 245, 239, 0.04);
  text-decoration: none;
  transition: border-color 160ms ease, background 160ms ease;
}

.info-link:hover {
  border-color: var(--ink);
  background: rgba(247, 245, 239, 0.08);
}

.info-link span {
  font-size: clamp(18px, 2vw, 24px);
  line-height: 1.35;
}

.info-link small {
  color: var(--muted);
  font-size: 13px;
  line-height: 1.7;
}

.ad-section {
  background: #0b0b0b;
}

.ad-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: clamp(14px, 2vw, 22px);
}

.ad-slot {
  display: flex;
  min-height: 160px;
  flex-direction: column;
  justify-content: space-between;
  padding: clamp(18px, 3vw, 28px);
  border: 1px dashed var(--line);
  background: rgba(247, 245, 239, 0.04);
  color: var(--muted);
}

.ad-label {
  width: fit-content;
  padding: 2px 8px;
  border: 1px solid var(--line);
  color: var(--ink);
  font-size: 12px;
}

.ad-slot p {
  margin: 28px 0 0;
}

@media (max-width: 860px) {
  .pc_only {
    display: none;
  }

  .sp_only {
    display: inline;
  }

  .site-header {
    position: sticky;
    align-items: center;
    flex-direction: row;
    flex-wrap: wrap;
    gap: 16px;
  }

  .nav-toggle-label {
    display: inline-flex;
    width: 42px;
    height: 42px;
    margin-left: auto;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    border: 1px solid var(--line);
    cursor: pointer;
  }

  .nav-toggle-label span {
    display: block;
    width: 18px;
    height: 1px;
    background: var(--ink);
    transition: transform 180ms ease, opacity 180ms ease;
  }

  .nav-toggle:checked + .nav-toggle-label span:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }

  .nav-toggle:checked + .nav-toggle-label span:nth-child(2) {
    opacity: 0;
  }

  .nav-toggle:checked + .nav-toggle-label span:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }

  .site-nav {
    display: none;
    flex-basis: 100%;
    width: 100%;
    padding-top: 14px;
    border-top: 1px solid var(--line);
  }

  .nav-toggle:checked ~ .site-nav {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .hero,
  .tool-card,
  .split-section,
  .notice,
  .text-columns,
  .info-grid,
  .ad-grid {
    grid-template-columns: 1fr;
  }

  .hero {
    min-height: auto;
  }

  .section-heading {
    display: block;
  }

  .section-heading h2,
  .section-title-small {
    font-size: 22px;
  }

  .tool-thumb {
    max-width: 420px;
  }

  .app-guide-thumb {
    max-width: 420px;
  }

  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (max-width: 520px) {
  .site-nav,
  .footer-nav {
    gap: 8px 14px;
    font-size: 12px;
  }

  .hero h1 {
    font-size: clamp(50px, 12vw, 86px);
  }

  .tool-card {
    padding: 14px;
  }

  .button {
    width: 100%;
  }

  .button-row {
    width: 100%;
  }
}