/* ============================================
   Kawanishi Lab - Pastel Pop Theme
   ============================================ */

:root {
  --pastel-pink: #FFB5C2;
  --pastel-blue: #B5D8FF;
  --pastel-purple: #D4B5FF;
  --pastel-mint: #B5FFDA;
  --pastel-yellow: #FFF3B5;
  --pastel-orange: #FFD4B5;
  --pastel-lavender: #E8DEFF;
  --pastel-sky: #D6EFFF;
  --bg-light: #FDFBFF;
  --text-dark: #2D2B3D;
  --text-muted: #6B6880;
  --card-shadow: 0 4px 20px rgba(180, 160, 255, 0.15);
  --card-hover-shadow: 0 8px 32px rgba(180, 160, 255, 0.25);
  --gradient-hero: linear-gradient(135deg, #E8DEFF 0%, #D6EFFF 50%, #FFE8F0 100%);
  --gradient-accent: linear-gradient(135deg, #D4B5FF, #B5D8FF);
  --border-radius-lg: 1.2rem;
  --border-radius-md: 0.8rem;
}

/* Global */
body {
  font-family: 'Noto Sans JP', 'Inter', sans-serif;
  background-color: var(--bg-light);
  color: var(--text-dark);
  overflow-x: hidden;
}

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

/* Animated background blobs */
.blob-bg {
  position: fixed;
  top: 0; left: 0;
  width: 100%; height: 100%;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.35;
  animation: blobFloat 20s ease-in-out infinite alternate;
}

.blob-1 {
  width: 500px; height: 500px;
  background: var(--pastel-purple);
  top: -10%; left: -5%;
  animation-delay: 0s;
}
.blob-2 {
  width: 400px; height: 400px;
  background: var(--pastel-blue);
  top: 40%; right: -10%;
  animation-delay: -5s;
}
.blob-3 {
  width: 350px; height: 350px;
  background: var(--pastel-pink);
  bottom: -5%; left: 30%;
  animation-delay: -10s;
}

@keyframes blobFloat {
  0%   { transform: translate(0, 0) scale(1); }
  33%  { transform: translate(30px, -30px) scale(1.05); }
  66%  { transform: translate(-20px, 20px) scale(0.95); }
  100% { transform: translate(10px, -10px) scale(1.02); }
}

/* Navbar */
.navbar {
  background: rgba(255, 255, 255, 0.8) !important;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid rgba(212, 181, 255, 0.2);
  padding: 0.8rem 0;
  transition: all 0.3s ease;
}

.navbar-brand {
  font-weight: 800;
  font-size: 1.3rem;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-link {
  font-weight: 600;
  color: var(--text-dark) !important;
  margin: 0 0.3rem;
  padding: 0.5rem 1rem !important;
  border-radius: 2rem;
  transition: all 0.3s ease;
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  background: var(--pastel-lavender);
  color: var(--text-dark) !important;
}

/* Language Toggle */
.lang-toggle {
  display: inline-flex;
  background: var(--pastel-lavender);
  border-radius: 2rem;
  padding: 3px;
  gap: 2px;
}

.lang-toggle .btn {
  border: none;
  border-radius: 2rem;
  padding: 0.3rem 1rem;
  font-size: 0.85rem;
  font-weight: 700;
  color: var(--text-muted);
  background: transparent;
  transition: all 0.3s ease;
}

.lang-toggle .btn.active {
  background: white;
  color: var(--text-dark);
  box-shadow: 0 2px 8px rgba(0,0,0,0.08);
}

/* Hero Section */
.hero-section {
  background: var(--gradient-hero);
  min-height: 70vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: '';
  position: absolute;
  top: -50%;
  right: -20%;
  width: 600px;
  height: 600px;
  background: var(--pastel-purple);
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.3;
}

.hero-section::after {
  content: '';
  position: absolute;
  bottom: -30%;
  left: -10%;
  width: 500px;
  height: 500px;
  background: var(--pastel-blue);
  border-radius: 50%;
  filter: blur(100px);
  opacity: 0.3;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-title {
  font-size: 3rem;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 1rem;
}

.hero-subtitle {
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--text-muted);
}

.hero-badge {
  display: inline-block;
  background: white;
  padding: 0.5rem 1.2rem;
  border-radius: 2rem;
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-dark);
  box-shadow: var(--card-shadow);
  margin-bottom: 1.5rem;
}

/* Cards */
.pop-card {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(10px);
  border: 1px solid rgba(212, 181, 255, 0.2);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
  box-shadow: var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  height: 100%;
}

.pop-card:hover {
  transform: translateY(-6px);
  box-shadow: var(--card-hover-shadow);
}

.pop-card .card-icon {
  width: 60px;
  height: 60px;
  border-radius: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: 1.2rem;
}

.icon-purple { background: var(--pastel-purple); }
.icon-blue   { background: var(--pastel-blue); }
.icon-pink   { background: var(--pastel-pink); }
.icon-mint   { background: var(--pastel-mint); }
.icon-yellow { background: var(--pastel-yellow); }
.icon-orange { background: var(--pastel-orange); }

/* Section Styling */
.section {
  padding: 5rem 0;
}

.section-title {
  font-size: 2.2rem;
  font-weight: 900;
  margin-bottom: 1rem;
  position: relative;
  display: inline-block;
}

.section-title::after {
  content: '';
  position: absolute;
  bottom: -8px;
  left: 0;
  width: 60px;
  height: 4px;
  background: var(--gradient-accent);
  border-radius: 2px;
}

.section-subtitle {
  color: var(--text-muted);
  font-size: 1.1rem;
  margin-bottom: 3rem;
}

/* Tag / Chip */
.pop-tag {
  display: inline-block;
  padding: 0.35rem 1rem;
  border-radius: 2rem;
  font-size: 0.85rem;
  font-weight: 600;
  margin: 0.25rem;
  background: var(--pastel-lavender);
  color: var(--text-dark);
  transition: all 0.3s ease;
}

.pop-tag:hover {
  transform: scale(1.05);
}

.pop-tag.tag-blue   { background: var(--pastel-blue); }
.pop-tag.tag-pink   { background: var(--pastel-pink); }
.pop-tag.tag-mint   { background: var(--pastel-mint); }
.pop-tag.tag-yellow { background: var(--pastel-yellow); }
.pop-tag.tag-orange { background: var(--pastel-orange); }

/* Research Topic Cards */
.topic-card {
  background: rgba(255,255,255,0.9);
  border-radius: var(--border-radius-lg);
  padding: 1.8rem;
  border-left: 4px solid;
  box-shadow: var(--card-shadow);
  transition: all 0.3s ease;
  margin-bottom: 1.5rem;
}

.topic-card:hover {
  transform: translateX(6px);
  box-shadow: var(--card-hover-shadow);
}

.topic-card.border-purple { border-left-color: var(--pastel-purple); }
.topic-card.border-blue   { border-left-color: var(--pastel-blue); }
.topic-card.border-pink   { border-left-color: var(--pastel-pink); }
.topic-card.border-mint   { border-left-color: var(--pastel-mint); }

/* Publication List */
.pub-item {
  background: rgba(255,255,255,0.85);
  border-radius: var(--border-radius-md);
  padding: 1.5rem;
  margin-bottom: 1rem;
  border: 1px solid rgba(212, 181, 255, 0.15);
  transition: all 0.3s ease;
}

.pub-item:hover {
  box-shadow: var(--card-shadow);
  transform: translateX(4px);
}

.pub-year-badge {
  display: inline-block;
  background: var(--gradient-accent);
  color: white;
  font-weight: 700;
  padding: 0.3rem 1rem;
  border-radius: 2rem;
  font-size: 0.9rem;
  margin-bottom: 1rem;
}

/* Member Card */
.member-card {
  background: rgba(255,255,255,0.9);
  border-radius: var(--border-radius-lg);
  padding: 2.5rem;
  text-align: center;
  box-shadow: var(--card-shadow);
  transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.member-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--card-hover-shadow);
}

.member-avatar {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  background: var(--gradient-accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 3rem;
  color: white;
  margin: 0 auto 1.5rem;
  box-shadow: 0 4px 20px rgba(212, 181, 255, 0.4);
}

.member-role {
  display: inline-block;
  background: var(--pastel-lavender);
  padding: 0.3rem 1rem;
  border-radius: 2rem;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.8rem;
}

/* Button */
.btn-pop {
  background: var(--gradient-accent);
  color: white;
  border: none;
  border-radius: 2rem;
  padding: 0.7rem 2rem;
  font-weight: 700;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(212, 181, 255, 0.4);
}

.btn-pop:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(212, 181, 255, 0.6);
  color: white;
}

.btn-outline-pop {
  border: 2px solid var(--pastel-purple);
  color: var(--text-dark);
  border-radius: 2rem;
  padding: 0.7rem 2rem;
  font-weight: 700;
  background: transparent;
  transition: all 0.3s ease;
}

.btn-outline-pop:hover {
  background: var(--pastel-lavender);
  border-color: var(--pastel-purple);
  color: var(--text-dark);
  transform: translateY(-2px);
}

/* Footer */
.footer {
  background: rgba(255,255,255,0.9);
  backdrop-filter: blur(20px);
  border-top: 1px solid rgba(212, 181, 255, 0.2);
  padding: 3rem 0 2rem;
}

.footer-brand {
  font-weight: 800;
  font-size: 1.2rem;
  background: var(--gradient-accent);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Page Header */
.page-header {
  background: var(--gradient-hero);
  padding: 8rem 0 4rem;
  position: relative;
  overflow: hidden;
}

.page-header::before {
  content: '';
  position: absolute;
  top: -30%;
  right: -10%;
  width: 400px;
  height: 400px;
  background: var(--pastel-purple);
  border-radius: 50%;
  filter: blur(80px);
  opacity: 0.25;
}

/* Animations */
.fade-in-up {
  opacity: 0;
  transform: translateY(30px);
  animation: fadeInUp 0.8s ease forwards;
}

@keyframes fadeInUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }
.delay-5 { animation-delay: 0.5s; }
.delay-6 { animation-delay: 0.6s; }

/* Responsive */
@media (max-width: 768px) {
  .hero-title {
    font-size: 2rem;
  }
  .hero-section {
    min-height: 50vh;
  }
  .section {
    padding: 3rem 0;
  }
  .section-title {
    font-size: 1.7rem;
  }
}

/* Smooth scroll */
html {
  scroll-behavior: smooth;
}

/* Decorative floating shapes */
.floating-shapes {
  position: absolute;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  pointer-events: none;
  overflow: hidden;
  z-index: 0;
}

.shape {
  position: absolute;
  border-radius: 50%;
  opacity: 0.15;
}

.shape-1 {
  width: 80px; height: 80px;
  background: var(--pastel-pink);
  top: 20%; right: 15%;
  animation: float 6s ease-in-out infinite;
}

.shape-2 {
  width: 50px; height: 50px;
  background: var(--pastel-yellow);
  top: 60%; right: 25%;
  animation: float 8s ease-in-out infinite reverse;
}

.shape-3 {
  width: 35px; height: 35px;
  background: var(--pastel-mint);
  top: 35%; left: 60%;
  animation: float 7s ease-in-out infinite;
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
}

@keyframes float {
  0%, 100% { transform: translateY(0) rotate(0deg); }
  50%      { transform: translateY(-20px) rotate(10deg); }
}