@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;500;700&display=swap');

:root {
  --color-primary: oklch(0.645 0.1748 280.69);
  --color-primary-dark: oklch(0.545 0.1748 280.69);
  --color-primary-light: oklch(0.745 0.1748 280.69);
  --color-white: oklch(0.9881 0 0);
  --color-black: oklch(0.3211 0 0);
  --color-gray-100: oklch(0.97 0 0);
  --color-gray-200: oklch(0.93 0 0);
  --color-gray-300: oklch(0.85 0 0);
  --color-gray-500: oklch(0.6 0 0);
  --color-gray-700: oklch(0.4 0 0);
  --color-gray-900: oklch(0.2 0 0);

  --font-size-xs: clamp(12px, calc(11.6px + 0.125vw), 14px);
  --font-size-sm: clamp(14px, calc(13.2px + 0.25vw), 18px);
  --font-size-base: clamp(16px, calc(15px + 0.3125vw), 21px);
  --font-size-lg: clamp(20px, calc(18.4px + 0.5vw), 28px);
  --font-size-xl: clamp(24px, calc(21.6px + 0.75vw), 36px);
  --font-size-2xl: clamp(28px, calc(24px + 1.25vw), 48px);
  --font-size-3xl: clamp(32px, calc(26px + 1.875vw), 62px);

  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-2xl: 4rem;
  --spacing-3xl: 6rem;

  --max-width: 1200px;
  --header-height: 80px;
  --header-height-mobile: 60px;

  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
}

*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans JP', sans-serif;
  font-size: var(--font-size-sm);
  line-height: 1.8;
  color: var(--color-gray-900);
  background-color: var(--color-white);
  overflow-x: hidden;
}

body.menu-open {
  overflow: hidden;
}

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

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition-fast);
}

ul,
ol {
  list-style: none;
}

h1, h2, h3, h4, h5, h6 {
  line-height: 1.4;
  font-weight: 700;
}

h1 {
  font-size: var(--font-size-2xl);
}

h2 {
  font-size: var(--font-size-xl);
}

h3 {
  font-size: var(--font-size-lg);
}

.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--spacing-md);
}

.section {
  padding-block: var(--spacing-3xl);
}

.section-title {
  text-align: center;
  margin-bottom: var(--spacing-xl);
  color: var(--color-primary);
  position: relative;
  padding-bottom: var(--spacing-sm);
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60px;
  height: 3px;
  background-color: var(--color-primary);
}

.btn {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  background-color: var(--color-primary);
  color: var(--color-white);
  border: 2px solid var(--color-primary);
  border-radius: 4px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.btn:hover {
  background-color: var(--color-primary-dark);
  border-color: var(--color-primary-dark);
}

.btn-outline {
  background-color: transparent;
  color: var(--color-primary);
}

.btn-outline:hover {
  background-color: var(--color-primary);
  color: var(--color-white);
}

@media (width < 768px) {
  :root {
    --header-height: var(--header-height-mobile);
  }

  .section {
    padding-block: var(--spacing-2xl);
  }
}