/* GLOBAL STYLES */
body {
  margin: 0;
  font-family: 'Segoe UI', sans-serif;
  background: #eef3ff;
  color: #333;
}

/* HEADER 
header.navbar {
  background: linear-gradient(90deg, #007bff, #3399ff);
  padding: 18px 25px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: white;
  position: sticky;
  top: 0;
  z-index: 999;
}


/* HEADER 
nav a {
  color: white;
  margin-left: 18px;
  text-decoration: none;
  font-weight: bold;
}
*/

/* HEADER */
header.navbar {
  background: linear-gradient(90deg,#007bff,#4da3ff);
  padding: 12px 22px;        /* 🔹 reduced vertical padding */
  display: flex;
  justify-content: space-between;
  align-items: center;
  color: white;
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  min-height: 40px;          /* 🔹 slimmer header */
}

nav a { 
  color: white;
  margin-left: 20px;
  text-decoration: none;
  font-weight: 600;
  font-size: 17px;          /* 🔹 increased from default */
  letter-spacing: 0.3px;   /* 🔹 subtle polish */
}

.logo {
  font-weight: 900;
  letter-spacing: 1px;
}


nav a:hover {
  text-decoration: underline;
}

/* HERO */
.hero {
  text-align: center;
  padding: 45px 20px 35px;
  background: url("../assets/images/BLinuxforDevops.jpg") center/cover no-repeat;
  color: black;
  text-shadow: 0 3px 8px rgba(0, 0, 0, 0.7);
  border-radius: 0 0 20px 20px;
}

.hero h1 {
  font-size: 40px;
  margin-bottom: 8px;
}

.hero p {
  font-size: 18px;
  margin-bottom: 15px;
}

.hero .back-btn {
  display: inline-block;
  padding: 9px 18px;
  background: white;
  color: #007bff;
  text-decoration: none;
  border-radius: 6px;
  font-weight: bold;
}

.hero .back-btn:hover {
  background: #e6efff;
}

/* FLOATING SIDEBAR MENU */
.sidebar-menu {
  position: fixed;
  top: 150px;
  right: 20px;
  width: 260px;
  background: #8a2be2; /* medium violet */
  border-radius: 18px;
  padding: 18px;
  box-shadow: 0 6px 14px rgba(0, 0, 0, 0.25);
  z-index: 900;
}

.sidebar-menu h3 {
  text-align: center;
  color: white;
  margin-bottom: 12px;
  font-size: 16px;
}

.sidebar-menu a {
  display: block;
  color: white;
  text-decoration: none;
  padding: 8px 12px;
  border-radius: 10px;
  margin: 5px 0;
  font-size: 14px;
  line-height: 1.4;
}

.sidebar-menu a:hover {
  background: #6f1fc1; /* darker violet hover */
}

/* CONTENT */
.container {
  max-width: 950px;
  margin: 40px auto;
  padding: 25px;
  padding-right: 320px; /* leave space for sidebar */
}

.section {
  background: white;
  padding: 25px;
  border-radius: 15px;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
  margin-bottom: 25px;
}

.section h2 {
  color: #007bff;
}

.section p,
.section li {
  font-size: 16px;
  line-height: 1.7;
}

/* BOTTOM BACK BUTTON */
.back-btn-bottom {
  display: inline-block;
  margin-top: 20px;
  padding: 10px 18px;
  background: #007bff;
  color: white;
  text-decoration: none;
  border-radius: 6px;
  font-weight: bold;
}

.back-btn-bottom:hover {
  background: #005fcc;
}

/* FOOTER */
footer {
  background: #007bff;
  color: white;
  text-align: center;
  padding: 15px;
  margin-top: 30px;
  border-radius: 8px;
}

footer a {
  color: white;
  text-decoration: none;
  margin: 0 10px;
  font-weight: bold;
}

footer a:hover {
  text-decoration: underline;
}

/* MOBILE RESPONSIVE */
@media (max-width: 768px) {
  .sidebar-menu {
    display: none;
  }
  .container {
    padding-right: 25px;
  }
}

/* FORCE ACTIVE SIDEBAR HIGHLIGHT */
.sidebar-menu a.active {
  background-color: #000000 !important;
  color: #ffffff !important;
  font-weight: 700;
  border-left: 4px solid #ffffff;
}



/* AdSense safe container */
.ad-slot {
  min-height: 280px;          /* prevents layout shift */
  width: 100%;
  margin: 20px 0;
  display: block;
}

/* 🔹 DROPDOWN MENU – LIGHT BLUE + BOLD */

.nav-dropdown {
  position: relative;
  display: inline-block;
}

/* Parent menu should look like normal nav links */
.nav-dropdown > span {
  cursor: pointer;
  padding: 8px 10px;
  display: inline-block;
  font-weight: inherit;   /* 🔑 key fix */
  color: inherit;         /* ensures white text */
}


/* Dropdown popup */
.dropdown-menu {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 220px;
  background:linear-gradient(90deg,#007bff,#4da3ff);
  box-shadow: 0 6px 18px rgba(0,0,0,0.15);
  border-radius: 6px;
  z-index: 999;
}

/* Dropdown items */
.dropdown-menu a {
  display: block;
  padding: 10px 14px;
  font-weight: bold;
  color: white;
  text-decoration: none;
}

/* Hover inside dropdown */
.dropdown-menu a:hover {
  background:linear-gradient(90deg,#007bff,#4da3ff);
}

/* Show dropdown on hover */
.nav-dropdown:hover .dropdown-menu {
  display: block;
}


/* Sidebar submenu styling (generic, reusable) */
.lesson-with-submenu {
  display: flex;
  flex-direction: column;
}

.lesson-with-submenu > a {
  font-weight: bold;
  position: relative;
}

/* Submenu inside main sidebar menu */
.lesson-with-submenu {
  display: flex;
  flex-direction: column;
}

.lesson-with-submenu > a {
  font-weight: bold;
  color: #fff; /* main menu color */
  padding-left: 10px; /* small padding for alignment */
}

/* Submenu items inside main menu */
.lesson-with-submenu .submenu {
  display: flex;
  flex-direction: column;
  padding-left: 40px; /* indent submenu items */
}

.lesson-with-submenu .submenu a {
  font-size: 0.95em;
  color: #fff; /* white font for submenu */
  text-decoration: none;
  padding: 3px 0;
}

.lesson-with-submenu .submenu a:hover {
  color: #00bfff; /* light blue highlight on hover */
  font-weight: 500;
}