/* =============================================
   blog-common.css - ATLAS AI LAB（動作・アニメーション）
   ============================================= */

@import url('https://fonts.googleapis.com/css2?family=DM+Sans:ital,opsz,wght@0,9..40,400;0,9..40,500;0,9..40,600;0,9..40,700;0,9..40,800;0,9..40,900;1,9..40,400&family=Noto+Sans+JP:wght@400;500;600;700;800;900&display=swap');

:root {
  --font-sans: 'Noto Sans JP', 'DM Sans', sans-serif;
  --font-dmsans: 'DM Sans', sans-serif;
}

@layer base {
  html {
    scroll-behavior: smooth;
  }

  body {
    font-family: var(--font-sans);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
  }

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

.font-dmsans {
  font-family: var(--font-dmsans);
}

.font-sans {
  font-family: var(--font-sans);
}

.blog-header-entrance {
  animation: blogHeaderIn 0.3s ease-in-out forwards;
}

@keyframes blogHeaderIn {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

/* Scroll: translucent → solid + shadow */
.blog-header.is-scrolled {
  background-color: #ffffff;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.05);
}

.blog-nav-item__chevron {
  transition: transform 0.3s ease;
}

.blog-nav-item:hover .blog-nav-item__chevron {
  transform: rotate(180deg);
}

.blog-nav-dropdown {
  position: absolute;
  top: 80%;
  left: 0;
  min-width: 12rem;
  background-color: #ffffff;
  border: 1px solid #f1f5f9;
  border-radius: 12px;
  padding: 0.5rem 0;
  box-shadow: 0 20px 40px rgba(148, 163, 184, 0.3);
  opacity: 0;
  visibility: hidden;
  transform: translateY(-4px);
  transition: opacity 0.2s ease, visibility 0.2s ease, transform 0.2s ease;
  z-index: 200;
}

.blog-nav-dropdown--right {
  left: auto;
  right: 0;
}

.blog-nav-item:hover .blog-nav-dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.blog-nav-dropdown__link {
  display: block;
  padding: 0.5rem 1rem;
  font-size: 12px;
  font-weight: 500;
  color: #475569;
  transition: color 0.2s, background-color 0.2s;
}

.blog-nav-dropdown__link:hover {
  color: #2563eb;
  background-color: #f8fafc;
}

/* Mobile menu (AnimatePresence: y -20 → 0, opacity) */
.blog-mobile-menu {
  display: flex;
  flex-direction: column;
  position: absolute;
  top: 80px;
  left: 0;
  width: 100%;
  background-color: #ffffff;
  border-bottom: 1px solid #f1f5f9;
  padding: 1.5rem;
  gap: 1.25rem;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-20px);
  pointer-events: none;
  transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
}

.blog-mobile-menu.is-open {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
  pointer-events: auto;
}

body.blog-menu-open {
  overflow: hidden;
}

.blog-mobile-menu__section {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.blog-mobile-menu__label {
  font-family: 'DM Sans', sans-serif;
  font-size: 10px;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: #94a3b8;
}

.blog-mobile-menu__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.75rem;
}

.blog-mobile-menu__grid a {
  font-size: 14px;
  font-weight: 700;
  color: #0f172a;
  transition: color 0.2s;
}

.blog-mobile-menu__grid a:hover {
  color: #2563eb;
}

.blog-mobile-menu__cta {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  background-color: #2563eb;
  color: #ffffff;
  padding: 0.875rem 1.5rem;
  border-radius: 12px;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.05em;
  transition: background-color 0.2s;
}

.blog-mobile-menu__cta:hover {
  background-color: #3b82f6;
}

/* Scroll-in sections (whileInView: y 15 → 0) */
.blog-animate-in {
  opacity: 0;
  transform: translateY(15px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.blog-animate-in.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.blog-animate-in.delay-1 { transition-delay: 0.1s; }
.blog-animate-in.delay-2 { transition-delay: 0.2s; }
.blog-animate-in.delay-3 { transition-delay: 0.3s; }

/* Carousel category badge */
.animate-fade-in {
  animation: blogFadeIn 0.5s ease forwards;
}

@keyframes blogFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}