/* 変数・リセット・タイポグラフィ・共通ユーティリティ */

:root {
  --color-light: #f7f7f3;
  --color-dark: #1b1b1b;
  --color-bg: var(--color-light);
  --color-text: var(--color-dark);
  --color-line: color-mix(in srgb, var(--color-text) 18%, transparent);

  --font-ja: "Zen Kaku Gothic New", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Noto Sans JP", Meiryo, sans-serif;
  --font-en: "Space Grotesk", sans-serif;

  --space-outer: clamp(16px, 5vw, 96px);
  --space-section: clamp(72px, 12vw, 160px);
  --space-stack: clamp(16px, 2vw, 32px);

  --header-pad-y: clamp(16px, 2.2vw, 28px);
  --header-height: calc(var(--header-pad-y) * 2 + 1.7em);

  --text-measure: 40rem;
  --line-width: 1px;
}

[data-theme="light"] {
  --color-bg: var(--color-light);
  --color-text: var(--color-dark);
  color-scheme: light;
}

[data-theme="dark"] {
  --color-bg: var(--color-dark);
  --color-text: var(--color-light);
  color-scheme: dark;
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
  background-color: var(--color-bg);
}

html:not(.is-loading):not(.is-fv-hide-scrollbar):not(.is-fv-scroll-lock) {
  overflow-y: scroll;
  scrollbar-gutter: stable;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: var(--font-ja);
  font-weight: 400;
  font-size: clamp(16px, 1.15vw, 18px);
  line-height: 1.7;
  background-color: var(--color-bg);
  color: var(--color-text);
}

img,
svg,
video,
iframe {
  max-width: 100%;
  height: auto;
  display: block;
}

button,
input,
select,
textarea {
  font: inherit;
}

h1,
h2,
h3,
h4,
h5,
h6,
p,
ul,
ol,
figure,
blockquote,
dl {
  margin: 0;
}

a {
  color: inherit;
}

:focus-visible {
  outline: 2px solid currentColor;
  outline-offset: 3px;
}

.screen-reader-text {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.font-en {
  font-family: var(--font-en);
}

.link-line {
  display: block;
  width: 100%;
  height: 1px;
  background-color: currentColor;
  transform: scaleX(1);
  transform-origin: left center;
  opacity: 0.55;
  transition: transform 0.4s ease, opacity 0.4s ease;
}

@media (hover: hover) and (pointer: fine) {
  .link-line {
    transform: scaleX(0.16);
    opacity: 0.7;
  }

  a:hover .link-line {
    transform: scaleX(1);
    opacity: 1;
  }
}

.prose {
  max-width: var(--text-measure);
}

.prose > * + * {
  margin-top: var(--space-stack);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  left: var(--space-outer);
  top: 0;
  z-index: 201;
  padding: 0.5rem 0.75rem;
  background-color: var(--color-dark);
  color: var(--color-light);
  text-decoration: none;
  transform: translateY(-120%);
}

.skip-link:focus {
  transform: translateY(0.75rem);
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}