* {
  box-sizing: border-box;
}

:root {
  /* LIGHT MODE - STANDARD */
  --bg-color: #f4f1ea;
  --text-color: #2c2c2c;
  --card-bg: #ffffff;
  --accent-color: #5d5d5d;
  --magic-gold: #b39b5d;
  --border-style: 1px solid rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] {
  /* DARK MODE */
  --bg-color: #1a1a1a;
  --card-bg: #2d2d2d;
  --text-color: #f0f0f0;
  --accent-color: #ff6b81;
  --border-style: 1px solid rgba(255, 255, 255, 0.1);
}

body {
  font-family: 'Playfair Display', serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  margin: 0;
  padding: 0;
  transition: background-color 0.3s, color 0.3s;
}

/* --- HEADER / HERO --- */
.hero {
  padding: 80px 20px;
  text-align: center;
  border-bottom: 2px double var(--magic-gold);
  margin-bottom: 40px;
}

.hero h1 {
  font-size: clamp(2rem, 8vw, 3.5rem);
  font-weight: 400;
  text-transform: uppercase;
  letter-spacing: 4px;
  margin: 0;
}

/* --- CONTROL PANEL --- */
#controls {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 30px;
  margin: 0 auto 50px;
  padding: 20px;
  max-width: 1000px;
}

.top-controls {
  display: flex;
  justify-content: center;
  margin-bottom: 20px;
  width: 100%;
}

.filter-group,
.sort-group {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  align-items: center;
  gap: 15px;
  width: 100%;
}

/* --- SEARCH BAR --- */
.search-wrapper {
  width: 100%;
  max-width: 600px;
  position: relative;
}

#searchInput {
  width: 100%;
  text-align: center;
  padding: 12px 15px 12px 40px;
  border: 1px solid var(--magic-gold);
  background: var(--card-bg);
  color: var(--text-color);
  font-family: inherit;
  font-size: 1rem;
  border-radius: 4px;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  opacity: 0.5;
}

/* --- BUTTONS (DARK MODE, SURPRISE, GENRE) --- */
.special-btn,
.filter-btn {
  background-color: var(--card-bg);
  color: var(--text-color);
  font-family: inherit;
  cursor: pointer;
  transition: all 0.3 ease;
}

#darkModeToggle,
.special-btn {
  border: 1px solid var(--magic-gold);
  padding: 10px 20px;
  border-radius: 20px;
  font-weight: bold;
  white-space: nowrap;
}

#darkModeToggle {
  position: absolute;
  top: 20px;
  right: 20px;
  z-index: 100;

  width: 45px;
  height: 45px;
  border-radius: 50%;
  border: 1px solid var(--magic-gold);
  background-color: var(--card-bg);
  cursor: pointer;

  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  transition: all 0.3s ease;
}

#darkModeToggle:hover {
  transform: scale(1.1);
  background-color: var(--magic-gold);
}

.filter-btn {
  border: 1px solid var(--accent-color);
  padding: 8px 16px;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.special-btn:hover,
.filter-btn:hover,
.filter-btn.active-filter {
  background-color: var(--magic-gold);
  color: white;
  border-color: var(--magic-gold);
  transform: translateY(-2px);
}

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

/* --- SORT --- */
.sort-container {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 0.8rem;
  text-transform: uppercase;
}

#sortSelector {
  padding: 8px;
  border: 1px solid var(--magic-gold);
  background: var(--card-bg);
  color: var(--text-color);
  font-family: inherit;
  border-radius: 4px;
}

/* --- BOOK CARDS (MASONRY)--- */
#container {
  column-width: 280px;
  column-gap: 25px;
  width: 90%;
  max-width: 1200px;
  margin: 0 auto;
  display: block;
}

.card {
  display: inline-block;
  width: 100%;
  margin-bottom: 25px;
  break-inside: avoid;
  position: relative;
  background-color: var(--card-bg);
  border-radius: 8px;
  overflow: hidden;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s, box-shadow 0.3s;
  break-inside: avoid;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.card img {
  width: 100%;
  height: auto;
  display: block;
  filter: sepia(0.2);
  transition: 0.3s;
}

.card:hover img {
  filter: sepia(0);
}

.card-content {
  padding: 20px;
}

.genre-tag {
  position: absolute;
  top: 10px;
  left: 10px;
  background: rgba(0, 0, 0, 0.7);
  color: white;
  padding: 4px 10px;
  font-size: 0.7rem;
  z-index: 5;
  border-radius: 4px;
}

.like-btn {
  position: absolute;
  top: 10px;
  right: 10px;
  z-index: 10;
  background: white;
  border: none;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  cursor: pointer;
  box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
  transition: transform 0.2s;
}

.like-btn.liked {
  background: #ff4757;
  transform: scale(1.1);
}

/* --- NO RESULTS --- */
.no-results {
  column-span: all;
  text-align: center;
  padding: 100px 20px;
  font-family: inherit;
  width: 100%;
}

.no-results p {
  font-style: italic;
  font-size: 1.5rem;
  margin-bottom: 10px;
  color: var(--magic-gold);
}

footer {
  width: 100%;
  padding: 40px 0 20px;
  text-align: center;
  font-family: inherit;
  color: var(--text-color);
  opacity: 0.8;
  margin-top: 50px;
  border-top: 1px solid rgba(0, 0, 0, 0.1);
}

[data-theme="dark"] footer {
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

/* --- RESPONSIVE --- */
@media (min-width: 768px) {
  .top-controls {
    flex-direction: row;
    justify-content: space-around;
    gap: 20px;
  }

  .search-wrapper {
    flex: 0 1 400px;
  }

  #searchInput {
    text-align: left;
  }
}