* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}
body {
  background-color: #0f0f0f;
  font-family: Arial, sans-serif;
  color: #fff;
}
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background-color: #212121;
  padding: 0 16px;
  height: 56px;
  position: sticky;
  top: 0;
  z-index: 10;
}
.header-left,
.header-center,
.header-right {
  display: flex;
  align-items: center;
}
.menu-button,
.icon-button,
.mic-button {
  background: none;
  border: none;
  cursor: pointer;
  margin-right: 16px;
  display: flex;
  align-items: center;
}
.menu-button svg,
.icon-button svg,
.mic-button svg {
  fill: #fff;
}
.logo {
  display: flex;
  align-items: center;
  font-weight: bold;
  font-size: 18px;
}
.header-center {
  flex: 1;
  justify-content: center;
}
.search-bar {
  display: flex;
  align-items: center;
  border: 1px solid #303030;
  border-right: none;
  background-color: #121212;
  height: 34px;
  border-radius: 2px 0 0 2px;
}
.search-bar input {
  width: 400px;
  background: transparent;
  border: none;
  color: #fff;
  padding: 0 8px;
  height: 100%;
  outline: none;
}
.search-bar input::placeholder {
  color: #aaa;
}
#search-button {
  background-color: #303030;
  border: none;
  padding: 0 16px;
  height: 34px;
  cursor: pointer;
  display: flex;
  align-items: center;
  border-radius: 0 2px 2px 0;
}
.mic-button {
  margin-left: 8px;
}
.header-right {
  gap: 8px;
}
.profile {
  width: 32px;
  height: 32px;
  cursor: pointer;
}
.sidebar {
  width: 72px;
  background-color: #212121;
  height: 100vh;
  position: fixed;
  top: 0;
  left: 0;
  overflow-y: auto;
  transition: width 0.3s;
  z-index: 5;
}
.sidebar-nav ul {
  padding-top: 57px; 
  list-style: none;
}
.sidebar-nav li {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 8px 0;
  cursor: pointer;
  color: #fff;
  transition: background-color 0.2s;
}
.sidebar-nav li:hover,
.sidebar-nav li.active {
  background-color: #383838;
}
.sidebar-nav li svg {
  margin-right: 0;
  min-width: 24px;
  max-width: 24px;
}
.sidebar.expanded .sidebar-nav li svg {
  margin-right: 24px;
}
.sidebar.expanded .sidebar-nav li {
  flex-direction: row;
  justify-content: flex-start;
  padding: 8px 16px;
}
.sidebar-nav li span {
  white-space: nowrap;
  opacity: 0;
  transition: opacity 0.3s;
  display: none;
}
.sidebar.expanded {
  width: 240px;
}
.sidebar.expanded li span {
  opacity: 1;
  display: block;
}
.main-content {
  margin-left: 72px;
  padding: 16px;
  transition: margin-left 0.3s;
}
.main-content.expanded {
  margin-left: 240px;
}
.category-scroll {
  display: flex;
  overflow-x: auto;
  margin-bottom: 16px;
}
.category-scroll button {
  background-color: #272727;
  border: none;
  color: #fff;
  padding: 8px 16px;
  margin-right: 8px;
  border-radius: 20px;
  white-space: nowrap;
  cursor: pointer;
}
.category-scroll button:hover {
  background-color: #383838;
}
.video-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 16px;
}
.video-item {
  background-color: #181818;
  border-radius: 8px;
  overflow: hidden;
}
.thumbnail img {
  width: 100%;
  display: block;
}
.video-details {
  display: flex;
  padding: 12px;
}
.channel-icon img {
  border-radius: 50%;
  width: 36px;
  height: 36px;
  margin-right: 12px;
}
.video-title {
  font-size: 14px;
  margin-bottom: 4px;
  color: #fff;
}
.channel-name,
.video-stats {
  font-size: 12px;
  color: #aaa;
}