:root {
  /* Brand */
  --color-primary-700: #0e5559;
  --color-primary-600: #146c70;
  --color-primary-300: #83b7b3;
  --color-primary-100: #dcefed;
  --color-primary-50: #eef7f5;

  /* Coral */
  --color-coral-700: #ad4938;
  --color-coral-500: #d06b58;
  --color-coral-100: #f5dfd9;
  --color-coral-50: #fbf1ee;

  /* Ochre */
  --color-ochre-700: #8a6419;
  --color-ochre-500: #c39a43;
  --color-ochre-100: #f2e7c9;
  --color-ochre-50: #faf6e9;

  /* Neutral */
  --color-ink-900: #253236;
  --color-ink-700: #3d4b4e;
  --color-ink-600: #5a686b;
  --color-ink-400: #889294;
  --color-border-strong: #b8c2bf;
  --color-border-default: #d7dedb;
  --color-surface-muted: #eef2f0;
  --color-canvas: #f6f3ec;
  --color-surface: #ffffff;

  /* Feedback */
  --color-success: #237a57;
  --color-warning: #8a6419;
  --color-danger: #ad4938;
  --color-info: #146c70;
  --color-focus: #1f6fe5;

  /* Semantic */
  --color-text-primary: var(--color-ink-900);
  --color-text-secondary: var(--color-ink-600);
  --color-text-inverse: var(--color-surface);
  --color-link: var(--color-primary-700);
  --color-background: var(--color-canvas);
  --color-background-surface: var(--color-surface);
  --color-action-primary: var(--color-primary-600);
  --color-action-primary-hover: var(--color-primary-700);

  /* Typography */
  --font-display:
    "Noto Serif JP",
    "Yu Mincho",
    "Hiragino Mincho ProN",
    serif;
  --font-body:
    "Noto Sans JP",
    "Hiragino Kaku Gothic ProN",
    "Yu Gothic",
    sans-serif;

  --font-size-display-xl: clamp(3rem, 7vw, 6.5rem);
  --font-size-display-lg: clamp(2.5rem, 5vw, 4.75rem);
  --font-size-heading-1: clamp(2.25rem, 4vw, 4rem);
  --font-size-heading-2: clamp(1.875rem, 3vw, 3rem);
  --font-size-heading-3: clamp(1.5rem, 2vw, 2rem);
  --font-size-heading-4: 1.25rem;
  --font-size-body-lg: 1.125rem;
  --font-size-body-md: 1rem;
  --font-size-body-sm: 0.875rem;
  --font-size-label: 0.75rem;

  /* Spacing */
  --space-0: 0;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  --space-32: 8rem;
  --space-40: 10rem;

  /* Layout */
  --container-main: 77.5rem;
  --container-text: 45rem;
  --container-wide: 90rem;
  --page-gutter-mobile: 1.25rem;
  --page-gutter-tablet: 2rem;
  --page-gutter-desktop: 4rem;

  /* Radius */
  --radius-none: 0;
  --radius-sm: 0.25rem;
  --radius-md: 0.5rem;
  --radius-lg: 1rem;
  --radius-full: 999px;

  /* Shadow */
  --shadow-sm: 0 1px 2px rgba(37, 50, 54, 0.08);
  --shadow-md: 0 12px 32px rgba(37, 50, 54, 0.1);
  --shadow-lg: 0 24px 64px rgba(37, 50, 54, 0.14);

  /* Motion */
  --motion-fast: 160ms;
  --motion-base: 320ms;
  --motion-slow: 600ms;
  --ease-standard: cubic-bezier(0.22, 1, 0.36, 1);
  --ease-in-out: cubic-bezier(0.65, 0, 0.35, 1);
}

html {
  color: var(--color-text-primary);
  background: var(--color-background);
  font-family: var(--font-body);
  font-size: 100%;
  line-height: 1.85;
}

body {
  margin: 0;
}

a {
  color: var(--color-link);
  text-underline-offset: 0.2em;
}

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

.container {
  width: min(
    calc(100% - var(--page-gutter-mobile) * 2),
    var(--container-main)
  );
  margin-inline: auto;
}

.button-primary {
  min-height: 52px;
  padding-inline: var(--space-6);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  border: 1px solid var(--color-action-primary);
  border-radius: var(--radius-sm);
  background: var(--color-action-primary);
  color: var(--color-text-inverse);
  font: 500 var(--font-size-body-md) / 1 var(--font-body);
  text-decoration: none;
  transition:
    background-color var(--motion-fast) var(--ease-standard),
    border-color var(--motion-fast) var(--ease-standard),
    transform var(--motion-fast) var(--ease-standard);
}

.button-primary:hover {
  border-color: var(--color-action-primary-hover);
  background: var(--color-action-primary-hover);
}

.button-primary:active {
  transform: translateY(1px);
}

@media (min-width: 768px) {
  .container {
    width: min(
      calc(100% - var(--page-gutter-tablet) * 2),
      var(--container-main)
    );
  }
}

@media (min-width: 1280px) {
  .container {
    width: min(
      calc(100% - var(--page-gutter-desktop) * 2),
      var(--container-main)
    );
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}