* {
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  line-height: 1.7;
  max-width: 900px;
  margin: 0 auto;
  padding: 20px;
  background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
  color: #e0e0e0;
  min-height: 100vh;
}

h1 {
  text-align: center;
  color: #fff;
  font-size: 2.5rem;
  margin-bottom: 10px;
  text-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
}

h2 {
  color: #ffd700;
  border-bottom: 3px solid #ffd700;
  padding-bottom: 10px;
  margin-top: 10px;
}

h3 {
  color: #00d4ff;
  margin-top: 30px;
}

.intro {
  text-align: center;
  font-size: 1.1rem;
  color: #aaa;
  margin-bottom: 40px;
}

.section {
  background: rgba(255, 255, 255, 0.05);
  border-radius: 15px;
  padding: 25px 30px;
  margin: 30px 0;
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.piece-types {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin: 20px 0;
}

.piece-card {
  background: rgba(255, 255, 255, 0.08);
  padding: 20px;
  border-radius: 10px;
  text-align: center;
}

.piece-card h4 {
  color: #ff6b6b;
  margin: 0 0 10px 0;
}

.algorithm {
  background: linear-gradient(135deg, #2d3436 0%, #000000 100%);
  border-left: 4px solid #ffd700;
  padding: 15px 20px;
  margin: 15px 0;
  border-radius: 0 10px 10px 0;
  font-family: 'Consolas', 'Courier New', monospace;
  font-size: 1.2rem;
  letter-spacing: 2px;
  color: #ffd700;
}

.algorithm-label {
  font-size: 0.85rem;
  color: #888;
  margin-bottom: 5px;
  font-family: 'Segoe UI', sans-serif;
  letter-spacing: normal;
}

.tip {
  background: rgba(0, 212, 255, 0.1);
  border: 1px solid #00d4ff;
  border-radius: 10px;
  padding: 15px 20px;
  margin: 20px 0;
}

.tip-title {
  color: #00d4ff;
  font-weight: bold;
  margin-bottom: 10px;
}

.bonus {
  background: rgba(255, 107, 107, 0.1);
  border: 1px solid #ff6b6b;
  border-radius: 10px;
  padding: 15px 20px;
  margin: 20px 0;
}

.bonus-title {
  color: #ff6b6b;
  font-weight: bold;
  margin-bottom: 10px;
}

.note {
  background: rgba(255, 215, 0, 0.1);
  border: 1px solid #ffd700;
  border-radius: 10px;
  padding: 15px 20px;
  margin: 20px 0;
  font-style: italic;
}

.image-placeholder {
  background: rgba(255, 255, 255, 0.1);
  border: 2px dashed rgba(255, 255, 255, 0.3);
  border-radius: 10px;
  padding: 40px;
  text-align: center;
  margin: 20px 0;
  color: #666;
}

.conditions {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 15px;
  margin: 20px 0;
}

.condition {
  background: rgba(255, 255, 255, 0.05);
  padding: 15px;
  border-radius: 10px;
  border-left: 3px solid #00d4ff;
}

.condition strong {
  color: #00d4ff;
}

.rotation-icons {
  font-size: 1.3rem;
}

ul, ol {
  padding-left: 25px;
}

li {
  margin: 10px 0;
}

.step-number {
  display: inline-block;
  background: #ffd700;
  color: #1a1a2e;
  width: 35px;
  height: 35px;
  border-radius: 50%;
  text-align: center;
  line-height: 35px;
  font-weight: bold;
  margin-right: 10px;
}

.final-note {
  text-align: center;
  font-size: 1.5rem;
  color: #4ade80;
  margin-top: 40px;
  padding: 30px;
  background: rgba(74, 222, 128, 0.1);
  border-radius: 15px;
  border: 2px solid #4ade80;
}

.media-container {
  text-align: center;
  margin: 20px 0;
}

.media-container img {
  max-width: 100%;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.media-container video {
  max-width: 100%;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 20px;
  margin: 20px 0;
}

.media-item {
  text-align: center;
}

.media-item video, .media-item img {
  width: 100%;
  border-radius: 10px;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

.media-item p {
  margin-top: 8px;
  color: #aaa;
  font-size: 0.9rem;
}

.condition video {
  width: 100%;
  margin-top: 10px;
  border-radius: 8px;
}

.condition img {
  width: 100%;
  margin-top: 10px;
  border-radius: 8px;
}