:root {
  color-scheme: light dark;
  --color-bg: #f5f5f7;
  --color-surface: #ffffff;
  --color-text: #1d1d1f;
  --color-text-muted: #6e6e73;
  --color-accent: #007aff;
  --color-accent-hover: #0056b3;
  --color-border: #d2d2d7;
  --color-nav-bg: #e8e8ed;
  --font-sans: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Hiragino Kaku Gothic ProN",
    "Noto Sans JP", "Segoe UI", sans-serif;
  --max-width: 42rem;
  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-pill: 999px;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.08);
  --space-xs: 0.5rem;
  --space-sm: 0.75rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #000000;
    --color-surface: #1c1c1e;
    --color-text: #f5f5f7;
    --color-text-muted: #98989d;
    --color-accent: #0a84ff;
    --color-accent-hover: #409cff;
    --color-border: #38383a;
    --color-nav-bg: #2c2c2e;
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.4);
  }
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 100%;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.8;
  color: var(--color-text);
  background: var(--color-bg);
}

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.15em;
}

a:hover {
  color: var(--color-accent-hover);
}

a:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
  border-radius: 2px;
}

.site-header {
  padding: var(--space-md);
  border-bottom: 1px solid var(--color-border);
  background: var(--color-surface);
}

.site-header__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: flex;
  justify-content: center;
}

.site-nav {
  display: inline-flex;
  flex-wrap: wrap;
  justify-content: center;
  padding: 0.25rem;
  gap: 0.25rem;
  font-size: 0.9375rem;
  background: var(--color-nav-bg);
  border-radius: var(--radius-pill);
}

.site-nav a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  min-height: 2.75rem;
  padding: 0 var(--space-lg);
  color: var(--color-text-muted);
  text-decoration: none;
  border-radius: var(--radius-pill);
  transition: background 0.15s ease, color 0.15s ease;
  white-space: nowrap;
}

.site-nav a:hover {
  color: var(--color-text);
}

.site-nav a[aria-current="page"] {
  color: var(--color-text);
  font-weight: 600;
  background: var(--color-surface);
  box-shadow: var(--shadow-sm);
  pointer-events: none;
}

main {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: var(--space-xl) var(--space-md) var(--space-2xl);
}

article h1 {
  margin: 0 0 var(--space-md);
  font-size: 1.75rem;
  line-height: 1.3;
  font-weight: 700;
  letter-spacing: -0.02em;
}

article h2 {
  margin: var(--space-2xl) 0 var(--space-md);
  padding-top: var(--space-lg);
  border-top: 1px solid var(--color-border);
  font-size: 1.125rem;
  line-height: 1.45;
  font-weight: 600;
}

article p,
article ul,
article ol {
  margin: 0 0 var(--space-md);
}

article ul,
article ol {
  padding-left: 1.375rem;
}

article li + li {
  margin-top: var(--space-xs);
}

.meta {
  display: inline-block;
  margin: 0 0 var(--space-xl);
  padding: 0.25rem 0.75rem;
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
}

.site-footer {
  max-width: var(--max-width);
  margin: 0 auto;
  width: 100%;
  padding: var(--space-lg) var(--space-md) var(--space-xl);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
  text-align: center;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.site-footer p {
  margin: 0;
}

/* トップ（ポートフォリオ / ロードマップ） */

body.hub {
  color-scheme: light;
  --hub-max-width: 44rem;
  --hub-icon-radius: 22%;
  --hub-accent-yurupomo: #c28c4d;
  --hub-accent-aiquiz: #2563eb;
  --hub-accent-sleepmine: #8b6f47;
}

body.hub main {
  max-width: var(--hub-max-width);
  padding: var(--space-2xl) var(--space-md) var(--space-2xl);
}

body.hub .site-footer {
  max-width: var(--hub-max-width);
}

.hub-intro {
  margin-bottom: var(--space-2xl);
  padding-bottom: var(--space-xl);
  border-bottom: 1px solid var(--color-border);
}

.hub-intro__eyebrow {
  margin: 0 0 var(--space-sm);
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.hub-intro__title {
  margin: 0 0 var(--space-md);
  font-size: clamp(1.75rem, 5vw, 2.25rem);
  line-height: 1.2;
  font-weight: 800;
  letter-spacing: -0.03em;
}

.hub-intro__lead {
  margin: 0;
  max-width: 36rem;
  font-size: 1.0625rem;
  line-height: 1.75;
  color: var(--color-text-muted);
}

.hub-section + .hub-section {
  margin-top: var(--space-2xl);
}

.hub-section__title {
  margin: 0 0 var(--space-md);
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--color-text-muted);
}

.hub-grid {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-md);
}

.hub-card {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  color: inherit;
  text-decoration: none;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  transition:
    border-color 0.15s ease,
    box-shadow 0.15s ease,
    transform 0.1s ease;
}

.hub-card:hover {
  color: inherit;
  box-shadow: var(--shadow-md);
  transform: translateY(-1px);
}

.hub-card:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.hub-card--legal:hover {
  border-color: var(--color-accent);
}

.hub-card__icon {
  flex-shrink: 0;
  width: 3.25rem;
  height: 3.25rem;
  border-radius: var(--hub-icon-radius);
  overflow: hidden;
  background: var(--color-bg);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--color-border) 80%, transparent);
}

.hub-card__icon img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.hub-card__icon--legal {
  display: grid;
  place-items: center;
  color: var(--color-accent);
  background: color-mix(in srgb, var(--color-accent) 10%, var(--color-surface));
}

.hub-card__body {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

.hub-card__title {
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--color-text);
}

.hub-card__desc {
  font-size: 0.875rem;
  line-height: 1.5;
  color: var(--color-text-muted);
}

.hub-card__chevron {
  flex-shrink: 0;
  width: 1.25rem;
  height: 1.25rem;
  color: var(--color-text-muted);
  opacity: 0.5;
  transition: opacity 0.15s ease, transform 0.15s ease;
}

.hub-card:hover .hub-card__chevron {
  opacity: 1;
  transform: translateX(2px);
}

.hub-timeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-lg);
}

.hub-timeline__item {
  display: grid;
  grid-template-columns: 5rem 1fr;
  gap: var(--space-md);
  align-items: start;
}

.hub-date {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  min-height: 100%;
  padding-right: 1.125rem;
  line-height: 1.1;
}

.hub-date::before {
  content: "";
  position: absolute;
  right: 0;
  top: 0.45rem;
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 0 3px var(--color-surface);
  transform: translateX(50%);
  z-index: 1;
}

.hub-timeline__item:not(:last-child) .hub-date::after {
  content: "";
  position: absolute;
  right: 0;
  top: 0.7rem;
  bottom: calc(var(--space-lg) * -1 - 0.2rem);
  width: 1px;
  background: color-mix(in srgb, var(--color-border) 85%, transparent);
  transform: translateX(50%);
}

.hub-date__month {
  margin: 0;
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--color-text-muted);
}

.hub-date__year {
  margin-top: 0.2rem;
  font-size: 1.375rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--color-text);
}

.hub-date__year--hidden {
  visibility: hidden;
}

.hub-timeline__card {
  padding: var(--space-md);
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
}

.hub-timeline__card--yurupomo {
  border-color: color-mix(in srgb, var(--hub-accent-yurupomo) 28%, var(--color-border));
}

.hub-timeline__card--aiquiz {
  border-color: color-mix(in srgb, var(--hub-accent-aiquiz) 28%, var(--color-border));
}

.hub-timeline__card--sleepmine {
  border-color: color-mix(in srgb, var(--hub-accent-sleepmine) 28%, var(--color-border));
}

.hub-timeline__card--placeholder {
  border-style: dashed;
  background: color-mix(in srgb, var(--color-bg) 65%, var(--color-surface));
}

.hub-timeline__store {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-sm);
  color: inherit;
  text-decoration: none;
}

.hub-timeline__store:hover {
  color: inherit;
}

.hub-timeline__store:hover .hub-timeline__name {
  color: var(--color-accent);
}

.hub-timeline__store--static {
  cursor: default;
}

.hub-timeline__icon {
  flex-shrink: 0;
  width: 3.25rem;
  height: 3.25rem;
  border-radius: var(--hub-icon-radius);
  object-fit: cover;
  background: var(--color-bg);
  box-shadow: inset 0 0 0 1px color-mix(in srgb, var(--color-border) 80%, transparent);
}

.hub-timeline__icon--empty {
  display: block;
  background: color-mix(in srgb, var(--color-border) 35%, var(--color-bg));
}

.hub-timeline__name {
  font-size: 1.0625rem;
  font-weight: 600;
  line-height: 1.35;
  color: var(--color-text);
  transition: color 0.15s ease;
}

.hub-timeline__desc {
  margin: 0 0 var(--space-md);
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--color-text-muted);
}

.hub-timeline__intro {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  padding: 0.35rem 0.65rem;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--color-accent);
  text-decoration: none;
  background: color-mix(in srgb, var(--color-accent) 8%, var(--color-surface));
  border: 1px solid color-mix(in srgb, var(--color-accent) 22%, var(--color-border));
  border-radius: var(--radius-pill);
  transition:
    background 0.15s ease,
    border-color 0.15s ease;
}

.hub-timeline__intro:hover {
  color: var(--color-accent-hover);
  background: color-mix(in srgb, var(--color-accent) 12%, var(--color-surface));
  border-color: color-mix(in srgb, var(--color-accent) 35%, var(--color-border));
}

.hub-timeline__chevron {
  width: 1rem;
  height: 1rem;
  flex-shrink: 0;
}

@media (max-width: 22rem) {
  .hub-timeline__item {
    grid-template-columns: 1fr;
    gap: var(--space-sm);
  }

  .hub-date {
    flex-direction: row;
    align-items: baseline;
    gap: 0.35rem;
    min-height: 0;
    padding-right: 0;
  }

  .hub-date::before,
  .hub-timeline__item:not(:last-child) .hub-date::after {
    display: none;
  }
}

@media (min-width: 36rem) {
  .hub-grid--legal {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 48rem) {
  body.hub main {
    padding-top: var(--space-2xl);
  }
}

.error-page {
  text-align: center;
  padding-top: var(--space-md);
}

.error-page h1 {
  margin: 0 0 var(--space-sm);
  font-size: 1.5rem;
  line-height: 1.35;
  font-weight: 700;
}

.error-page__code {
  margin: 0 0 var(--space-lg);
  font-size: 3rem;
  font-weight: 700;
  line-height: 1;
  color: var(--color-text-muted);
  letter-spacing: -0.03em;
}

.error-page p {
  margin: 0 0 var(--space-md);
  color: var(--color-text-muted);
}

.error-page p:last-child {
  margin-top: var(--space-xl);
}