:root {
  --primary: #00a2ff;
  --primary-light: #0099ff;
  --dark: #242424;
  --darker: #161616;
  --light: #f8fafc;
  --gray: #64748b;
  --sidebar-collapsed: 80px;
  --sidebar-expanded: 220px;
  --transition-speed: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: 'Segoe UI', Arial, sans-serif;
  background: var(--darker);
  color: var(--light);
  height: 100vh;
  display: flex;
  overflow: hidden;
}

/* Sidebar Styles */
.sidebar {
  width: var(--sidebar-collapsed);
  height: 100vh;
  padding: 1rem 0.5rem;
  background: var(--darker);
  left: 0;
  top: 0;
  z-index: 20;
  transition: width var(--transition-speed);
  overflow: hidden;
}

.sidebar:hover,
.sidebar:focus-within,
.sidebar.focused {
  width: var(--sidebar-expanded);
}

/* Logo Styles */
.logo {
  text-align: center;
  margin-bottom: 2rem;
  padding: 0 0.5rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
  padding-bottom: 1.5rem;
  white-space: nowrap;
  overflow: hidden;
}

.logo_img {
  width: 50px;
  height: 50px;
  margin-bottom: 0.5rem;
  margin-top: 0.5rem;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.1);
  transition: all var(--transition-speed);
}

.sidebar:hover .logo_img,
.sidebar:focus-within .logo_img,
.sidebar.focused .logo_img {
  transform: scale(1.1);
}

.logo h2 {
  color: var(--primary-light);
  font-size: 0;
  opacity: 0;
  margin: 0;
  font-weight: 600;
  letter-spacing: 0.5px;
  transition: 
    font-size var(--transition-speed),
    opacity var(--transition-speed);
}

.sidebar:hover .logo h2,
.sidebar:focus-within .logo h2,
.sidebar.focused .logo h2 {
  font-size: 1.3rem;
  opacity: 1;
}

/* Navigation Menu */
.nav-menu {
  list-style: none;
  flex-grow: 1;
  padding: 0 0.5rem;
  margin: 0;
  align-items: center;
}

.nav-item {
  margin-bottom: 1rem;
  position: relative;
}

.nav-link {
  display: flex;
  align-items: center;
  padding: 0.8rem;
  color: var(--light);
  text-decoration: none;
  border-radius: 6px;
  transition: all var(--transition-speed);
  font-size: 1rem;
  white-space: nowrap;
  overflow: hidden;
}

.nav-link i {
  min-width: 24px;
  font-size: 1.5rem;
  text-align: center;
  transition: margin-right var(--transition-speed);
}

.nav-link span {
  opacity: 0;
  width: 0;
  transition:
    opacity var(--transition-speed),
    width var(--transition-speed);
  margin-left: 0;
}

.sidebar:hover .nav-link span,
.sidebar:focus-within .nav-link span,
.sidebar.focused .nav-link span {
  opacity: 1;
  width: auto;
  margin-left: 1rem;
}

.sidebar:hover .nav-link i,
.sidebar:focus-within .nav-link i,
.sidebar.focused .nav-link i {
  margin-right: 1rem;
}

.nav-link:hover {
  background: rgba(59, 130, 246, 0.15);
  transform: translateX(5px);
}

.nav-link:focus {
  background: rgba(70, 70, 70, 0.575);
  outline: none;
  transform: scale(1.08);
  border: 2px solid rgb(255, 255, 255);
}

.nav-link.active {
  background: rgb(255, 255, 255);
  color: rgb(0, 0, 0);
  font-weight: 500;
  border-left: 3px solid var(--primary);
}