/* Base Layout */
body {
  margin: 0;
  display: flex;
  font-family: "Segoe UI", "Roboto", Arial, sans-serif;
  background: #f5f5f5;
  color: #333;
}

main {
  flex: 1;
  padding: 2rem;
}

@media (max-width: 900px) {
  aside#sidebar {
    position: static;
    width: 100%;
    min-height: auto;
    border-right: none;
  }
  main {
    margin-left: 0;
  }
}

/* Sidebar */
aside#sidebar {
  width: 280px;
  background: #fff;
  padding: 2rem 1rem;
  border-right: 1px solid #e5e7eb;
  min-height: 100vh;
  box-shadow: 1px 0 5px rgba(0, 0, 0, 0.05);
}

aside#sidebar nav a {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.5rem 0.75rem;
  border-radius: 0.375rem;
  font-weight: 500;
  color: #2563eb;
  text-decoration: none;
  transition: background 0.2s, color 0.2s;
}

aside#sidebar nav a:hover {
  background: #f3f4f6;
  color: #1e40af;
}

/* Headings */
h1 {
  font-size: 2.2rem;
  font-weight: bold;
  margin-bottom: 0.5rem;
  color: #2563eb;
}

.dashboard-desc {
  color: #374151;
  margin-bottom: 1.5rem;
}

/* Top Info */
.top-info {
  background: #f3f4f6;
  border-radius: 1rem;
  padding: 1rem 2rem;
  margin-bottom: 2rem;
  display: flex;
  gap: 2rem;
  align-items: center;
  font-size: 1.1rem;
}

/* Cards */
.card-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 2rem;
  margin-top: 2rem;
}

.card {
  background: #fff;
  border-radius: 1rem;
  padding: 2rem 1.5rem;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.07);
  transition: box-shadow 0.2s;
}

.card:hover {
  box-shadow: 0 4px 16px rgba(37, 99, 235, 0.15);
}

/* Checklist */
.checklist-section {
  margin-bottom: 2rem;
}

.checklist-item {
  display: flex;
  align-items: center;
  margin-bottom: 0.5rem;
}

.checklist-item label {
  margin-left: 0.5rem;
  cursor: pointer;
}

.checklist-item input:checked + label {
  text-decoration: line-through;
  color: #9ca3af;
}

/* Progress Bars */
.progress-bar-bg {
  background: #e5e7eb;
  border-radius: 9999px;
  height: 1rem;
  width: 100%;
  margin-top: 0.5rem;
}

.progress-bar {
  background: linear-gradient(90deg, #2563eb 60%, #60a5fa 100%);
  border-radius: 9999px;
  height: 1rem;
  width: 0%;
  transition: width 0.3s ease;
}

/* Resources */
.resource-links a {
  margin-right: 1rem;
  color: #2563eb;
  text-decoration: none;
}

/* Challenges */
.challenge-card {
  transition: all 0.3s ease;
  border-left: 4px solid transparent;
}

.challenge-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1),
    0 4px 6px -2px rgba(0, 0, 0, 0.05);
  border-left-color: #0ea5e9;
}

.solution-toggle {
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

.solution-toggle.active {
  max-height: 2000px;
}

/* Difficulty Tags */
.difficulty-easy {
  background-color: #ecfdf5;
  color: #059669;
}

.difficulty-medium {
  background-color: #fef3c7;
  color: #d97706;
}

.difficulty-hard {
  background-color: #fee2e2;
  color: #b91c1c;
}

.tag {
  transition: all 0.2s ease;
}

.tag:hover {
  transform: translateY(-1px);
}

/* Scrollbars */
.sidebar {
  scrollbar-width: thin;
  scrollbar-color: #e5e7eb #f3f4f6;
}

.sidebar::-webkit-scrollbar {
  width: 6px;
}

.sidebar::-webkit-scrollbar-track {
  background: #f3f4f6;
}

.sidebar::-webkit-scrollbar-thumb {
  background-color: #e5e7eb;
  border-radius: 6px;
}

/* Dark Mode */
.dark .progress-bar-bg {
  background: #374151;
}

.dark .progress-bar {
  background: #60a5fa;
}

.dark .sidebar::-webkit-scrollbar-track {
  background: #1f2937;
}

.dark .sidebar::-webkit-scrollbar-thumb {
  background-color: #4b5563;
}

.dark .challenge-card {
  background-color: #1f2937;
  border-color: #374151;
}

.dark .challenge-card:hover {
  border-left-color: #0ea5e9;
}

.dark .solution-content {
  background-color: #111827;
}

.dark .checklist-container {
  background-color: #1f2937;
  border-color: #374151;
}

.dark .checklist-item label {
  color: #e5e7eb;
}

.dark .checklist-item input:checked + label {
  color: #9ca3af;
}

.dark .checkmark {
  border-color: #4b5563;
}