/* ===== Base ===== */
* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  font-family: 'Montserrat', sans-serif;
  background-color: #f5f5f5;
  color: #374151;
  overflow-x: hidden;
}

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

/* ===== Navbar ===== */
.navbar {
  background-color: #f5f5f5;
  padding: 1rem 0;
  position: relative;
}

.navbar::after {
  content: '';
  display: block;
  width: 90%;
  height: 1px;
  background-color: #ddd;
  margin: 0 auto;
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.nav-left {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

.avatar img {
  width: 28px;
  height: 28px;
  cursor: pointer;
}

.name-title {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}

.my-name {
  font-weight: 700;
  color: #000;
}

.title {
  font-weight: 400;
  font-size: 0.9rem;
  color: #374151;
}

.nav-links {
  display: flex;
  align-items: center;
  position: relative;
}

.nav-links ul {
  list-style: none;
  display: flex;
  gap: 1.5rem;
  margin: 0;
  padding: 0;
}

.nav-links a {
  text-decoration: none;
  color: #000;
  font-weight: 400;
  transition: color 0.3s ease, letter-spacing 0.3s ease;
}

.nav-links a:hover {
  color: #2563eb;
  letter-spacing: 0.5px;
}

.close-btn {
  display: none;
}

/* ===== Mobile Navbar ===== */
@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 0;
    left: -250px;
    width: 250px;
    height: 100%;
    background-color: #f5f5f5;
    flex-direction: column;
    padding-top: 3rem;
    transition: left 0.4s ease;
    border-right: 1px solid #ddd;
    z-index: 1001;
  }

  .nav-links.active {
    left: 0;
  }

  .close-btn {
    display: block;
    font-size: 2rem;
    position: absolute;
    top: 1rem;
    right: 1.2rem;
    cursor: pointer;
  }

  .nav-links ul {
    flex-direction: column;
    align-items: center;
    gap: 1.2rem;
    margin-top: 2rem;
  }

  .nav-links a {
    font-size: 1.1rem;
  }

  .overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s ease;
    z-index: 1000;
  }

  .overlay.active {
    opacity: 1;
    pointer-events: auto;
  }
}

/* ===== Research Section ===== */
.research-section {
  background-color: #f5f5f5;
  padding: 4rem 1rem;
  text-align: center;
}

.research-container {
  max-width: 800px;
  margin: 0 auto;
}

.research-section h1 {
  font-size: 2.2rem;
  font-weight: 700;
  margin-bottom: 1rem;
  color: #000;
}

.research-intro {
  font-size: 1rem;
  color: #374151;
}

/* ===== Footer ===== */
.footer {
  background-color: #f5f5f5;
  padding: 2rem 1rem;
  font-size: 0.9rem;
  color: #374151;
  position: relative;
}

.footer::before {
  content: '';
  display: block;
  width: 90%;
  height: 1px;
  background-color: #ddd;
  margin: 0 auto;
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 2rem;
}

.footer-section {
  flex: 1;
  min-width: 200px;
}

.footer h4 {
  font-weight: 700;
  margin-bottom: 0.5rem;
  color: #000;
}

.footer a {
  text-decoration: none;
  color: rgb(108, 0, 0);
  transition: color 0.3s ease, letter-spacing 0.3s ease;
}

.footer a:hover {
  color: #1d4ed8;
  letter-spacing: 0.5px;
}

.footer .copyright {
  text-align: right;
}

@media (max-width: 768px) {
  .research-container h1 {
    font-size: 2rem;
  }

  .footer-container {
    flex-direction: column;
    text-align: center;
  }

  .footer .copyright {
    text-align: center;
    margin-top: 1rem;
  }
}