:root {
  --bg-color: #f4f4f4;
  --text-color: #333;
  --card-bg: #fff;
  --card-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --accent-color: #007bff;
  --accent-hover: #0056b3;
  --toggle-bg: #ddd;
  --toggle-icon: #333;
}

[data-theme="dark"] {
  --bg-color: #121212;
  --text-color: #e0e0e0;
  --card-bg: #1e1e1e;
  --card-shadow: 0 4px 6px rgba(0, 0, 0, 0.5);
  --accent-color: #58a6ff;
  --accent-hover: #1f6feb;
  --toggle-bg: #333;
  --toggle-icon: #ffd700;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  margin: 0;
  padding: 20px;
  background-color: var(--bg-color);
  color: var(--text-color);
  transition: background-color 0.3s, color 0.3s;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  max-width: 1200px;
  margin: 0 auto 30px;
  padding: 10px 0;
}

h1 {
  margin: 0;
  font-size: 2em;
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 50%;
  background-color: var(--toggle-bg);
  color: var(--toggle-icon);
  transition: background-color 0.3s, transform 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.theme-toggle svg {
  width: 24px;
  height: 24px;
  /* Use absolute positioning to overlap them if you want a morph effect, 
     but simpler display toggle is safer for now. 
     Let's use display: none for simplicity as requested, or opacity/transform for better effect. */
}

/* Logic: When Light Mode (default), show Moon (to switch to dark) or Sun? 
   Usually: Show the icon of the mode you will SWITCH TO, or the icon of the CURRENT mode.
   Let's show the CURRENT mode icon (Sun for Light, Moon for Dark).
*/

[data-theme="dark"] .sun-icon {
  display: none;
}

[data-theme="dark"] .moon-icon {
  display: block;
}

/* Default Light Mode */
.sun-icon {
  display: block;
}

.moon-icon {
  display: none;
}

.theme-toggle:hover {
  transform: scale(1.1);
}

.controls-container {
  margin-bottom: 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
}

#search-input {
  width: 100%;
  max-width: 500px;
  padding: 12px 20px;
  border: 1px solid #ccc;
  border-radius: 25px;
  font-size: 1rem;
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.1);
  transition: box-shadow 0.3s, border-color 0.3s;
  background-color: var(--card-bg);
  /* Use card-bg for input to blend with theme */
  color: var(--text-color);
}

#search-input:focus {
  outline: none;
  border-color: var(--accent-color);
  box-shadow: 0 0 0 3px rgba(0, 123, 255, 0.25);
}

#filter-container {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
}

.filter-btn {
  padding: 8px 16px;
  background-color: var(--card-bg);
  border: 1px solid #ccc;
  /* Or a lighter border variable */
  border-radius: 20px;
  cursor: pointer;
  font-size: 0.9rem;
  color: var(--text-color);
  transition: all 0.2s ease;
}

.filter-btn:hover {
  border-color: var(--accent-color);
  color: var(--accent-color);
}

.filter-btn.active {
  background-color: var(--accent-color);
  color: white;
  border-color: var(--accent-color);
}

#project-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
  list-style: none;
  padding: 0;
  max-width: 1200px;
  margin: 0 auto;
}

.project-card {
  background-color: var(--card-bg);
  border-radius: 12px;
  box-shadow: var(--card-shadow);
  overflow: hidden;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  display: flex;
  flex-direction: column;
}

.project-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 12px rgba(0, 0, 0, 0.15);
}

.card-thumbnail {
  width: 100%;
  height: 160px;
  background-color: #ddd;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.card-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.project-card:hover .card-thumbnail img {
  transform: scale(1.05);
}

.card-content {
  padding: 15px;
  flex-grow: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.project-title {
  display: block;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-color);
  text-decoration: none;
  margin-bottom: 8px;
}

.project-title:hover {
  color: var(--accent-color);
}

.card-footer {
  margin-top: 10px;
}

.view-btn {
  display: inline-block;
  padding: 8px 16px;
  background-color: var(--accent-color);
  color: white;
  text-decoration: none;
  border-radius: 6px;
  font-size: 0.9rem;
  transition: background-color 0.2s;
}

.view-btn:hover {
  background-color: var(--accent-hover);
  text-decoration: none;
}