:root {
  --color-base: #fafafa;
  --color-surface: #ffffff;
  --color-main: #111111;
  --color-sub: #555560;
  --color-muted: #8e8e98;
  --color-mist: #f2f2f4;
  --color-line: rgba(17, 17, 17, 0.1);

  --color-accent: #111111;
  --color-ai: #3d5afe;
  --color-ai-soft: rgba(61, 90, 254, 0.08);
  --color-cast: #b45309;

  --color-success: #10b981;
  --color-error: #ef4444;

  --font-jp: "Zen Kaku Gothic New", "Hiragino Sans", sans-serif;
  --font-jp-display: "Shippori Mincho B1", "Yu Mincho", serif;
  --font-en: "DM Sans", sans-serif;

  --text-hero: clamp(2rem, 5vw, 3.75rem);
  --text-section: clamp(1.625rem, 3vw, 2.625rem);
  --text-heading: clamp(1.0625rem, 1.6vw, 1.3125rem);
  --text-body: 1rem;
  --text-small: 0.875rem;
  --text-caption: 0.75rem;

  --space-section: 5rem;
  --space-block: 2.5rem;
  --container-max: 1160px;
  --container-padding: 1.25rem;
  --header-height: 3.75rem;

  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-card: 0 1px 2px rgba(0, 0, 0, 0.04), 0 12px 40px rgba(0, 0, 0, 0.06);
  --shadow-float: 0 24px 64px rgba(0, 0, 0, 0.1);

  --transition-base: 350ms cubic-bezier(0.22, 1, 0.36, 1);
  --transition-fast: 180ms ease;
}

@media (min-width: 768px) {
  :root {
    --space-section: 6.5rem;
    --space-block: 3rem;
    --container-padding: 2rem;
  }
}

@media (min-width: 1024px) {
  :root {
    --space-section: 8rem;
    --space-block: 3.5rem;
    --container-padding: 3rem;
  }
}

body {
  font-family: var(--font-jp);
  font-size: var(--text-body);
  font-weight: 400;
  line-height: 1.9;
  color: var(--color-sub);
  background: var(--color-base);
  -webkit-font-smoothing: antialiased;
  font-feature-settings: "palt" 1;
}

h1,
h2 {
  font-family: var(--font-jp-display);
  font-weight: 500;
  color: var(--color-main);
  line-height: 1.55;
  letter-spacing: 0.06em;
}

h3,
h4 {
  font-family: var(--font-jp);
  font-weight: 500;
  color: var(--color-main);
  line-height: 1.55;
  letter-spacing: 0.03em;
}

h1 { font-size: var(--text-hero); letter-spacing: 0.08em; }
h2 { font-size: var(--text-section); }
h3 { font-size: var(--text-heading); }

img { max-width: 100%; height: auto; }

::selection {
  background: var(--color-ai-soft);
  color: var(--color-main);
}

:focus-visible {
  outline: 2px solid var(--color-ai);
  outline-offset: 3px;
}

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

.en {
  font-family: var(--font-en);
  letter-spacing: 0.08em;
}