body {
  font-family: 'Poppins', 'Noto Sans JP', sans-serif;
  margin: 0;
  color: #222;
  background-color: #fdfdfd;
  line-height: 1.8;
}

/* ===== HERO SECTION ===== */
.hero {
  position: relative;
  background: url('/imgfile/private4/iwin_bg.jpg') center/cover no-repeat;
  width: 100%;
  height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  text-align: center;
  overflow: hidden;
}

.overlay {
  position: absolute;
  inset: 0;
  background: rgba(0, 20, 40, 0.6);
  backdrop-filter: blur(3px);
}

.hero-content {
  width: 100%;
  position: relative;
  z-index: 1;
  max-width: 900px;
  padding: 0 20px;
}

.hero-content h1 {
  font-size: 3.2em;
  font-weight: 700;
  margin-bottom: 15px;
  letter-spacing: 1px;
  text-shadow: 0 3px 10px rgba(0,0,0,0.5);
}

.subtitle {
  font-size: 1.2em;
  opacity: 0.95;
}

/* ===== SECTION BASE ===== */
section {
  max-width: 1200px;
  margin: 100px auto;
  padding: 0 40px;
}

h2 {
  font-size: 2em;
  color: #004a66;
  margin-bottom: 20px;
  position: relative;
  letter-spacing: 0.5px;
}

h2::after {
  content: "";
  display: block;
  width: 70px;
  height: 3px;
  background: #02ccba;
  margin-top: 10px;
}

p {
  font-size: 1.05em;
  color: #444;
  margin-bottom: 25px;
}

/* ===== RESEARCH SECTION ===== */
.research {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 50px;
}

.research .text {
  flex: 1 1 480px;
}

.research .image {
  flex: 1 1 500px;
}

.research .image img {
  width: 100%;
  border-radius: 14px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.15);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  cursor: pointer;
}

.research .image img:hover {
  transform: scale(1.03);
  box-shadow: 0 15px 35px rgba(0,0,0,0.2);
}

/* ===== EXPERIENCE GALLERY ===== */
.gallery {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 30px;
  justify-items: center;
  padding-bottom: 60px;
}

.gallery img {
  width: 100%;
  max-width: 400px;
  height: 250px;
  object-fit: cover;
  border-radius: 14px;
  box-shadow: 0 6px 18px rgba(0,0,0,0.12);
  cursor: pointer;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.gallery img:hover {
  transform: scale(1.03);
  box-shadow: 0 12px 25px rgba(0,0,0,0.18);
}

/* ===== CERTIFICATE ===== */
.certificate {
  text-align: center;
  margin-top: 50px;
}

.certificate img {
  width: 85%;
  max-width: 700px;
  border-radius: 10px;
  box-shadow: 0 6px 25px rgba(0,0,0,0.25);
  transition: transform 0.3s ease;
  cursor: pointer;
}

.certificate img:hover {
  transform: scale(1.02);
}

/* ===== BACK BUTTON ===== */
.back-container {
  text-align: center;
  margin: 80px 0;
}

.back-button {
  display: inline-block;
  background: linear-gradient(90deg, #006b8f, #02ccba);
  color: white;
  padding: 12px 28px;
  border-radius: 30px;
  text-decoration: none;
  font-weight: bold;
  box-shadow: 0 6px 20px rgba(0,0,0,0.15);
  transition: all 0.4s ease;
}

.back-button:hover {
  background: linear-gradient(90deg, #02ccba, #006b8f);
  transform: translateY(-4px);
  box-shadow: 0 10px 30px rgba(0,0,0,0.25);
}

/* ===== FOOTER ===== */
footer {
  background: #001d2a;
  color: white;
  text-align: center;
  padding: 30px;
  font-size: 0.9em;
  letter-spacing: 0.5px;
}

/* ===== MODAL (画像拡大) ===== */
.modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.9);
  justify-content: center;
  align-items: center;
  z-index: 999;
}

.modal img {
  max-width: 90%;
  max-height: 90%;
  border-radius: 10px;
  animation: zoomIn 0.5s ease;
}

.close {
  position: absolute;
  top: 40px;
  right: 60px;
  color: white;
  font-size: 45px;
  cursor: pointer;
  transition: color 0.3s;
}
.close:hover {
  color: #02ccba;
}

/* ===== ANIMATIONS ===== */
@keyframes zoomIn {
  from { transform: scale(0.85); opacity: 0; }
  to { transform: scale(1); opacity: 1; }
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .hero-content h1 { font-size: 2.2em; }
  .subtitle { font-size: 1em; }
  .research { flex-direction: column; }
  .gallery { grid-template-columns: 1fr; }
}