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

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  background-color: var(--bg-color);
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* header */
header {
  background: var(--card-bg);
  color: var(--text-main);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  height: 100px;
  box-shadow: 0 4px 10px var(--shadow-color);
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

header h1 {
  margin: 0;
  font-size: 2.2rem;
  font-weight: 600;
}

/* main layout */
.main-layout {
  display: flex;
  gap: 2rem;
  flex: 1;
  align-items: stretch;
  padding: 2rem;
  color: var(--text-main);
  max-width: 1200px;
  margin: 20px auto;
  width: 100%;
}

/* layout article */
.main-layout article {
  flex: 3;
  display: flex;
  flex-direction: column;
  border-radius: 12px;
  background: var(--card-bg);
  padding: 2.5rem;
  box-shadow: 0 4px 15px var(--shadow-color);
  line-height: 1.6;
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.main-layout article p {
  color: var(--text-main);
  font-size: 1.05rem;
}

/* layout aside */
.main-layout aside {
  flex: 1;
  border-radius: 12px;
  background: var(--card-bg);
  padding: 2rem;
  box-shadow: 0 4px 15px var(--shadow-color);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

/* footer */
footer {
  width: 100%;
  background-color: var(--footer-bg);
  color: var(--text-muted);
  text-align: center;
  height: 60px;
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: auto;
  transition: background-color 0.3s ease;
}

/* images in aside */
aside img {
  border-radius: 12px;
  box-shadow: 0 4px 10px var(--shadow-color);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

aside img:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 15px var(--shadow-hover);
}

/* Lightbox Styles */
.lightbox {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(15, 23, 42, 0.9);
    backdrop-filter: blur(8px);
    justify-content: center;
    align-items: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.lightbox.active {
    opacity: 1;
}

.lightbox-content {
    max-width: 90%;
    max-height: 85vh;
    border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
    transform: scale(0.8);
    transition: transform 0.3s ease;
}

.lightbox.active .lightbox-content {
    transform: scale(1);
}

.lightbox-close {
    position: absolute;
    top: 30px;
    right: 40px;
    color: var(--text-muted);
    font-size: 50px;
    font-weight: bold;
    cursor: pointer;
    transition: color 0.3s;
}

.lightbox-close:hover {
    color: var(--text-main);
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
  .main-layout {
    flex-direction: column;
    padding: 1rem;
    gap: 1.5rem;
  }
  
  header h1 {
    font-size: 1.8rem;
  }
}