/* Modern CSS using CSS Variables & Grid/Flexbox */

:root {
  /* Colors */
  --color-primary: #2E7D32;
  --color-primary-light: #66BB6A;
  --color-accent: #F57C00;
  --color-accent-hover: #E65100;
  --color-text-main: #333333;
  --color-text-sub: #757575;
  --color-bg-body: #F5F5F5;
  --color-bg-white: #FFFFFF;
  --color-border: #E0E0E0;

  /* Typography */
  --font-family-base: "Noto Sans JP", "Hiragino Sans", "Meiryo", sans-serif;
  --font-size-base: 16px;
  --line-height-base: 1.6;

  /* Spacing */
  --spacing-xs: 8px;
  --spacing-sm: 16px;
  --spacing-md: 24px;
  --spacing-lg: 48px;
  --spacing-xl: 80px;

  /* Border Radius */
  --radius-sm: 4px;
  --radius-md: 8px;
}

/* Reset & Base */
*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text-main);
  background-color: var(--color-bg-body);
}

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.2s;
}

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

/* Layout Utilities */
.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-sm);
}

.grid {
  display: grid;
  gap: var(--spacing-md);
}

.grid-2 {
  grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
  grid-template-columns: repeat(3, 1fr);
}

.flex {
  display: flex;
  gap: var(--spacing-md);
}

.flex-col {
  flex-direction: column;
}

.justify-between {
  justify-content: space-between;
}

.items-center {
  align-items: center;
}

@media (max-width: 768px) {

  .grid-2,
  .grid-3 {
    grid-template-columns: 1fr;
  }

  .mobile-hidden {
    display: none;
  }
}

/* Components */
.btn {
  display: inline-block;
  padding: 12px 24px;
  background-color: var(--color-accent);
  color: white;
  border-radius: var(--radius-sm);
  font-weight: 700;
  text-align: center;
  border: none;
  cursor: pointer;
  transition: background 0.2s;
}

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

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

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

.card {
  background: var(--color-bg-white);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

/* Header */
.site-header {
  background: var(--color-bg-white);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.nav-link {
  color: var(--color-text-main);
  font-weight: 700;
  padding: var(--spacing-sm);
}

.nav-link:hover {
  color: var(--color-primary);
}

/* Footer */
.site-footer {
  background: #263238;
  /* Dark for footer */
  color: white;
  padding: var(--spacing-lg) 0;
  margin-top: var(--spacing-xl);
}

.site-footer a {
  color: #B0BEC5;
}

.site-footer a:hover {
  color: white;
}