* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Segoe UI", sans-serif;
}

body {
  background: #faf9f6;
  color: #2b3a42;
}

/* ---------- HEADER ---------- */
.top-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 30px;
  background: #fdfcf8;
  border-bottom: 1px solid #e5e5e5;
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo h2 {
  margin: 0;
  font-size: 20px;
}

.logo span {
  font-size: 13px;
  color: #6b7c85;
}

.nav-tabs {
  display: flex;
  gap: 10px;
}

.tab {
  border: none;
  background: transparent;
  padding: 8px 14px;
  border-radius: 20px;
  cursor: pointer;
  font-size: 14px;
  color: #566b73;
  transition: 0.3s;
}

.tab:hover {
  background: #e7f5f2;
}

.tab.active {
  background: #dff4ee;
  color: #159f8b;
  font-weight: 600;
}

/* ---------- SECTIONS ---------- */
.section {
  display: none;
  padding: 50px 60px;
  animation: fadeIn 0.5s ease-in;
}

.active-section {
  display: block;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

.section-title {
  text-align: center;
  font-size: 28px;
  margin-bottom: 40px;
}

/* ---------- HERO CARD ---------- */
.hero-card {
  display: flex;
  justify-content: space-between;
  gap: 40px;
  background: white;
  padding: 40px;
  border-radius: 20px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.05);
  margin-bottom: 50px;
}

.hero-text h4 {
  color: #8ca5ad;
  letter-spacing: 1px;
  margin-bottom: 10px;
}

.hero-text h1 {
  font-size: 36px;
  color: #159f8b;
  margin-bottom: 20px;
}

.guide-box {
  display: flex;
  align-items: center;
  gap: 12px;
  background: #f4f7f6;
  padding: 12px 18px;
  border-radius: 15px;
  width: fit-content;
}

.hero-image {
  display: flex;
  align-items: center;
  justify-content: center;
}

.image-placeholder {
  width: 280px;
  height: 200px;
  border-radius: 20px;
  background: linear-gradient(135deg, #e2f6f2, #f5fbfa);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-size: 40px;
  color: #159f8b;
}

/* ---------- TEAM ---------- */
.team-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 25px;
}

.team-card {
  background: white;
  padding: 25px;
  border-radius: 18px;
  text-align: center;
  box-shadow: 0 8px 20px rgba(0,0,0,0.05);
  transition: transform 0.3s;
}

.team-card:hover {
  transform: translateY(-6px);
}

.team-card h3 {
  margin-top: 10px;
  font-size: 18px;
}

.team-card p {
  margin-top: 5px;
  font-size: 14px;
  color: #6b7c85;
}

/* ---------- CHEMICALS ---------- */
.center-header {
  text-align: center;
  margin-bottom: 40px;
}

.center-header h1 {
  font-size: 34px;
  color: #159f8b;
  margin: 10px 0;
}

.center-header p {
  color: #6b7c85;
}

.filter-buttons {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-bottom: 30px;
}

.filter {
  border: none;
  padding: 8px 16px;
  border-radius: 20px;
  background: #f1f1f1;
  cursor: pointer;
}

.filter.active {
  background: #159f8b;
  color: white;
}

.chem-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 25px;
}

.chem-card {
  background: white;
  padding: 25px;
  border-radius: 18px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.05);
  transition: transform 0.3s;
}

.chem-card:hover {
  transform: translateY(-6px);
}

.chem-card h3 {
  margin-top: 10px;
  font-size: 18px;
}

.chem-card small {
  color: #8ca5ad;
}

.chem-card p {
  margin-top: 10px;
  font-size: 14px;
  color: #566b73;
}

.tag {
  display: inline-block;
  margin-top: 8px;
  background: #f0f5f4;
  padding: 4px 10px;
  border-radius: 12px;
  font-size: 12px;
  color: #159f8b;
}

/* ---------- PROCESS ---------- */
.progress-bar {
  width: 80%;
  height: 6px;
  background: #e5e5e5;
  border-radius: 10px;
  margin: 20px auto;
  overflow: hidden;
}

#progress-fill {
  height: 100%;
  width: 11%;
  background: #159f8b;
  transition: width 0.4s ease;
}

#step-indicator {
  text-align: center;
  color: #159f8b;
  font-weight: 600;
  margin-bottom: 30px;
}

.process-card {
  max-width: 700px;
  margin: auto;
  background: white;
  padding: 35px;
  border-radius: 20px;
  box-shadow: 0 10px 25px rgba(0,0,0,0.05);
  text-align: center;
}

.process-card h2 {
  font-size: 26px;
  margin-bottom: 20px;
}

.animation-box {
  height: 180px;
  background: #f7faf9;
  border-radius: 15px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  overflow: hidden;
}

.animation {
  font-size: 50px;
  animation: bounce 1.5s infinite;
}

@keyframes bounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-12px); }
}

.process-card p {
  color: #566b73;
  margin-bottom: 15px;
}

.duration {
  display: inline-block;
  background: #e7f5f2;
  padding: 6px 14px;
  border-radius: 20px;
  color: #159f8b;
  font-size: 14px;
}

.process-controls {
  margin-top: 30px;
  display: flex;
  justify-content: center;
  gap: 15px;
}

.process-controls button {
  padding: 10px 20px;
  border-radius: 25px;
  border: none;
  cursor: pointer;
  font-size: 14px;
}

.process-controls button:hover {
  opacity: 0.9;
}

.process-controls button:nth-child(1) {
  background: #f1f1f1;
}

.play-btn {
  background: #159f8b;
  color: white;
}

.next-btn {
  background: #f9a825;
  color: white;
}

.reset-btn {
  background: transparent;
  border: 1px solid #ccc !important;
}

/* ---------- DOTS ---------- */
.step-dots {
  display: flex;
  justify-content: center;
  gap: 10px;
  margin-top: 25px;
}

.dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #d6d6d6;
  cursor: pointer;
}

.dot.active {
  background: #159f8b;
}

/* ---------- DIAGRAMS ---------- */
.diagram-box {
  background: white;
  padding: 25px;
  border-radius: 18px;
  margin: 20px auto;
  max-width: 700px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.05);
}

/* ---------- VIDEOS ---------- */
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 25px;
}

.video-grid iframe {
  width: 100%;
  height: 200px;
  border-radius: 15px;
  border: none;
}

/* ---------- Q&A ---------- */
.qa-box {
  background: white;
  padding: 25px;
  border-radius: 18px;
  margin: 20px auto;
  max-width: 700px;
  box-shadow: 0 8px 20px rgba(0,0,0,0.05);
}

.qa-box h3 {
  margin-bottom: 10px;
}

.qa-box ul {
  margin-left: 20px;
  margin-top: 10px;
}

.section-header {
  text-align: center;
  margin-bottom: 40px;
}

.icon-circle {
  width: 70px;
  height: 70px;
  margin: 0 auto 15px;
  border-radius: 50%;
  background: #e6f7f3;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 30px;
}

.section-header h2 {
  font-size: 36px;
  color: #1fa39a;
}

.section-header p {
  color: #6b7c85;
  font-size: 16px;
}

.sub-title {
  text-align: center;
  font-size: 26px;
  margin: 50px 0 30px;
}

.app-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 25px;
  margin-bottom: 50px;
}

.app-card {
  background: white;
  padding: 25px;
  border-radius: 16px;
  text-align: center;
  box-shadow: 0 8px 20px rgba(0,0,0,0.08);
  transition: transform 0.3s ease;
}

.app-card:hover {
  transform: translateY(-6px);
}

.app-icon {
  width: 60px;
  height: 60px;
  margin: 0 auto 15px;
  border-radius: 50%;
  background: #e6f7f3;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 26px;
}

.app-card h4 {
  margin-bottom: 8px;
  font-size: 18px;
}

.app-card p {
  font-size: 14px;
  color: #6b7c85;
}

.advantages-box {
  background: white;
  padding: 30px;
  border-radius: 18px;
  box-shadow: 0 8px 22px rgba(0,0,0,0.08);
  margin-bottom: 60px;
}

.advantages-box h3 {
  text-align: center;
  margin-bottom: 25px;
  font-size: 24px;
}

.advantages-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 15px 40px;
  list-style: none;
  padding: 0;
}

.advantages-list li {
  font-size: 15px;
  color: #2f3b43;
}

.qa-box details {
  background: white;
  padding: 18px 22px;
  border-radius: 14px;
  box-shadow: 0 6px 18px rgba(0,0,0,0.07);
  margin-bottom: 15px;
  cursor: pointer;
}

.qa-box summary {
  font-weight: 600;
  font-size: 16px;
}

.qa-box p {
  margin-top: 10px;
  color: #5a6b75;
  font-size: 14px;
}


/* ---------- FOOTER ---------- */
footer {
  text-align: center;
  padding: 30px;
  color: #6b7c85;
  font-size: 14px;
}

/* ---------- GROUP PHOTO ---------- */
.group-photo {
  width: 100%;
  max-width: 170px;   /* small size */
  border-radius: 20px;
  box-shadow: 0 12px 25px rgba(0,0,0,0.15);
}