/* --- HEADER STYLES --- */
.header {
  height: 70px;
  background-color: white;
  position: fixed;
  display: flex;
  align-items: center;
  justify-content: space-between;
  top: 0px;
  left: 0px;
  right: 0px;
  z-index: 100;
  box-shadow: 0 2px 12px rgba(44,62,80,0.07);
}

.header p {
  font-family: Oswald, Arial, sans-serif;
  color: black;
  font-weight: 500;
  font-size: 17px;
  margin: 0;
}

.left-section {
  padding-top: 5px;
  padding-left: 10px;
  height: 60px;
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav-home {
  display: flex;
  align-items: center;
  text-decoration: none;
  color: black;
}

.iit-logo {
  height: 60px;
}

.ham-logo {
  height: 28px;
  width: 28px;
}

.right-section {
  height: 70px;
  display: flex;
  align-items: center;
  gap: 15px;
  margin-right: 10px;
  position: relative;
}

.right-section a {
  text-decoration: none;
}

.right-section button {
  border-radius: 50%;
  background: none;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  padding: 6px;
  transition: background 0.2s;
}
.head {
  text-decoration: none;
  color: black;
}

.head:hover p {
  transition: 0.3s;
  text-decoration: underline;
  cursor: pointer;
}

/* --- SUBMENU (Hamburger) --- */
.sub-menu {
  display: none;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: absolute;
  top: 60px;
  right: 10px;
  width: 200px;
  background: #789ae9;
  border-radius: 10px;
  box-shadow: 0px 0px 10px rgba(0,0,0,0.1);
  z-index: 200;
  padding: 10px 0;
  transition: opacity 0.4s, transform 0.4s;
}

.option {
  width: 100%;
  text-align: center;
  padding: 8px 0;
  border-bottom: 1px solid #eee;
  font-family: Oswald, Arial, sans-serif;
  color: #222;
  text-decoration: none;
  transition: background 0.2s;
  display: block;
}

.option:last-child {
  border-bottom: none;
}

.option:hover {
  background: #fff;
}

/* Hamburger menu hidden by default, shown only when needed */
.toggle {
  display: none;
  background: none;
  border: none;
  padding: 0;
  margin-left: 8px;
  cursor: pointer;
}

/* --- RESPONSIVE: Hide links one by one and show hamburger only when needed --- */
@media (max-width: 1100px) { .nav-contact { display: none; } .toggle { display: flex; } }
@media (max-width: 1000px) { .nav-news { display: none; } }
@media (max-width: 900px)  { .nav-activities { display: none; } }
@media (max-width: 800px)  { .nav-projects { display: none; } }
@media (max-width: 700px)  { .nav-patents { display: none; } }
@media (max-width: 600px)  { .nav-publications { display: none; } }
@media (max-width: 500px)  { .nav-research { display: none; } }
@media (max-width: 400px)  { .nav-group { display: none; } }