:root {
  --main-bg: #ffffff;
  --main-color: #002c6c;
  --accent: #f2d024;
  --text-color: #001f3f;
  --button-bg: #ffffff;
  --button-text: #002c6c;
}

body.dark-mode {
  --main-bg: #121212;
  --main-color: #1f1f1f;
  --accent: #ffcc00;
  --text-color: #e0e0e0;
  --button-bg: #1f1f1f;
  --button-text: #ffffff;
}

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

body {
  background-color: var(--main-bg);
  color: var(--text-color);
  transition: 0.3s ease;
}

/* Header */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--main-color);
  color: white;
  padding: 15px 20px;
}

.logo {
  font-size: 22px;
  font-weight: bold;
  color: var(--accent);
}

.tagline {
  font-size: 12px;
}

.menu {
  font-size: 24px;
  cursor: pointer;
}

/* Dark mode toggle switch */
.switch {
  position: relative;
  display: inline-block;
  width: 40px;
  height: 22px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider-round {
  position: absolute;
  cursor: pointer;
  top: 0; left: 0; right: 0; bottom: 0;
  background-color: #ccc;
  border-radius: 22px;
  transition: .4s;
}

.slider-round:before {
  position: absolute;
  content: "";
  height: 16px; width: 16px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  border-radius: 50%;
  transition: .4s;
}

.switch input:checked + .slider-round {
  background-color: #4caf50;
}

.switch input:checked + .slider-round:before {
  transform: translateX(18px);
}

/* Sidebar */
.sidebar {
  position: fixed;
  left: -250px;
  top: 0;
  width: 250px;
  height: 100%;
  background: var(--main-color);
  color: white;
  transition: left 0.3s;
  padding-top: 60px;
  z-index: 1000;
}

.sidebar.open {
  left: 0;
}

.sidebar ul {
  list-style: none;
  padding: 0;
}

.sidebar li {
  padding: 15px 20px;
  border-bottom: 1px solid #ffffff20;
  cursor: pointer;
}

.sidebar li:hover {
  background: #001f3f;
}

.close-btn {
  position: absolute;
  top: 10px;
  right: 20px;
  font-size: 30px;
  cursor: pointer;
}

/* Hero Slider */
.hero {
  position: relative;
  height: 250px;
  overflow: hidden;
}

.slider img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: none;
  position: absolute;
  top: 0;
  left: 0;
}

.slider img.active {
  display: block;
  animation: fade 1s;
}

@keyframes fade {
  from {opacity: 0;}
  to {opacity: 1;}
}

.slider-text {
  position: absolute;
  bottom: 20px;
  left: 20px;
  color: white;
  background: rgba(0, 0, 0, 0.6);
  padding: 15px;
}

.slider-text h2 {
  color: var(--accent);
}

/* Buttons Grid */
.buttons-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 15px;
  padding: 20px;
}

button {
  background: var(--button-bg);
  border: 2px solid var(--main-color);
  color: var(--button-text);
  padding: 15px;
  font-size: 14px;
  border-radius: 10px;
  cursor: pointer;
  transition: 0.3s ease;
}

button:hover {
  background: var(--main-color);
  color: white;
}

/* Bottom Navigation */
.bottom-nav {
  display: flex;
  justify-content: space-around;
  background: #f0f0f0;
  padding: 10px 0;
  position: fixed;
  bottom: 0;
  width: 100%;
}

.nav-icon {
  font-size: 20px;
  cursor: pointer;
}

/* Desktop adjustments */
@media (min-width: 768px) {
  .bottom-nav {
    display: none;
  }

  .buttons-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}