/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --color-primary: #2563eb;
  --color-primary-dark: #1d4ed8;
  --color-text: #1f2937;
  --color-text-light: #6b7280;
  --color-bg: #ffffff;
  --color-bg-alt: #f9fafb;
  --color-border: #e5e7eb;
  --font-family: 'Noto Sans JP', sans-serif;
  --container-width: 1200px;
  --header-height: 80px;
}

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  font-size: 16px;
  line-height: 1.8;
  color: var(--color-text);
  background-color: var(--color-bg);
}

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--color-primary-dark);
}

/* Container */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-height);
  background: transparent;
  border-bottom: none;
  z-index: 1000;
  transition: background 0.3s ease, border-color 0.3s ease;
}

.site-header.scrolled {
  background: var(--color-bg);
  border-bottom: 1px solid var(--color-border);
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.logo {
  display: flex;
  align-items: center;
}

.logo img {
  height: 50px;
  width: auto;
}

/* Main Content */
main {
  margin-top: var(--header-height);
}


/* Page Content */
.page-content {
  padding: 60px 0;
}

.page-header {
  margin-bottom: 3rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--color-border);
}

.page-header h1 {
  font-size: 2rem;
  font-weight: 700;
}

.content h2 {
  font-size: 1.5rem;
  margin: 2rem 0 1rem;
  text-align: left;
}

.content h3 {
  font-size: 1.25rem;
  margin: 1.5rem 0 0.75rem;
}

.content p {
  margin-bottom: 1rem;
}

.content ul, .content ol {
  margin: 1rem 0;
  padding-left: 1.5rem;
}

.content li {
  margin-bottom: 0.5rem;
}

/* Apps Section */
.apps-section {
  padding: 80px 0;
  background: var(--color-bg-alt);
}

.section-title {
  font-size: 1.5rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 3rem;
  color: var(--color-text);
  position: relative;
}

.section-title::after {
  content: '';
  display: block;
  width: 40px;
  height: 3px;
  background: var(--color-primary);
  margin: 0.75rem auto 0;
  border-radius: 2px;
}

.app-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 1.5rem;
  max-width: 900px;
  margin: 0 auto;
}

.app-card {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 1.5rem;
  color: var(--color-text);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.app-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
  color: var(--color-text);
}

.app-card-icon {
  flex-shrink: 0;
  width: 56px;
  height: 56px;
  background: linear-gradient(135deg, #eff6ff, #dbeafe);
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
}

.app-card-icon svg {
  width: 28px;
  height: 28px;
}

.app-card-icon img {
  width: 40px;
  height: 40px;
  border-radius: 8px;
}

.app-card-body {
  flex: 1;
  min-width: 0;
}

.app-card-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 0.25rem;
}

.app-card-description {
  font-size: 0.875rem;
  color: var(--color-text-light);
  line-height: 1.6;
  margin: 0;
}

.app-card-arrow {
  flex-shrink: 0;
  color: var(--color-border);
  transition: color 0.2s ease, transform 0.2s ease;
}

.app-card-arrow svg {
  width: 20px;
  height: 20px;
}

.app-card:hover .app-card-arrow {
  color: var(--color-primary);
  transform: translateX(3px);
}

/* Footer */
.site-footer {
  background: var(--color-text);
  color: #fff;
  padding: 30px 0;
}

.copyright {
  text-align: center;
  opacity: 0.6;
  font-size: 0.875rem;
}

/* Responsive */
@media (max-width: 768px) {
  :root {
    --header-height: 60px;
  }

  .logo img {
    height: 35px;
  }

  .page-content {
    padding: 40px 0;
  }

  .page-header h1 {
    font-size: 1.5rem;
  }

  .content h2 {
    font-size: 1.25rem;
  }

  .apps-section {
    padding: 50px 0;
  }

  .app-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 480px) {
  .container {
    padding: 0 15px;
  }
}