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

    body {
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
      min-height: 100vh;
      padding: 40px 20px;
    }

    .container {
      max-width: 1400px;
      margin: 0 auto;
    }

    header {
      text-align: center;
      color: white;
      margin-bottom: 50px;
    }

    header h1 {
      font-size: 3rem;
      margin-bottom: 10px;
      text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    }

    header p {
      font-size: 1.2rem;
      opacity: 0.9;
    }

    .grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
      gap: 30px;
      margin-bottom: 40px;
    }

    .button-card {
      background: white;
      border-radius: 15px;
      padding: 40px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      min-height: 220px;
      box-shadow: 0 10px 30px rgba(0,0,0,0.2);
      transition: transform 0.3s ease;
    }

    .button-card:hover {
      transform: translateY(-5px);
    }

    .button-card h3 {
      margin-bottom: 30px;
      color: #333;
      font-size: 1.1rem;
    }

    /* Base button styles */
    .btn {
      padding: 15px 40px;
      font-size: 1rem;
      font-weight: 600;
      border: none;
      cursor: pointer;
      position: relative;
      overflow: hidden;
      transition: all 0.3s ease;
      font-family: inherit;
    }

    /* 1. Slide from Left */
    .btn-slide-left {
      background: #667eea;
      color: white;
      border-radius: 50px;
    }

    .btn-slide-left::before {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100%;
      background: #764ba2;
      transition: left 0.3s ease;
      z-index: -1;
    }

    .btn-slide-left:hover::before {
      left: 0;
    }

    /* 2. Slide from Right */
    .btn-slide-right {
      background: #ff6b6b;
      color: white;
      border-radius: 50px;
    }

    .btn-slide-right::before {
      content: '';
      position: absolute;
      top: 0;
      right: -100%;
      width: 100%;
      height: 100%;
      background: #ee5a6f;
      transition: right 0.3s ease;
      z-index: -1;
    }

    .btn-slide-right:hover::before {
      right: 0;
    }

    /* 3. Slide from Top */
    .btn-slide-top {
      background: #00b894;
      color: white;
      border-radius: 10px;
    }

    .btn-slide-top::before {
      content: '';
      position: absolute;
      top: -100%;
      left: 0;
      width: 100%;
      height: 100%;
      background: #00cec9;
      transition: top 0.3s ease;
      z-index: -1;
    }

    .btn-slide-top:hover::before {
      top: 0;
    }

    /* 4. Slide from Bottom */
    .btn-slide-bottom {
      background: #feca57;
      color: #333;
      border-radius: 10px;
    }

    .btn-slide-bottom::before {
      content: '';
      position: absolute;
      bottom: -100%;
      left: 0;
      width: 100%;
      height: 100%;
      background: #ff9f43;
      transition: bottom 0.3s ease;
      z-index: -1;
    }

    .btn-slide-bottom:hover::before {
      bottom: 0;
    }

    /* 5. Expand Circle */
    .btn-expand-circle {
      background: #c471f5;
      color: white;
      border-radius: 50px;
    }

    .btn-expand-circle::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 0;
      height: 0;
      border-radius: 50%;
      background: #fa71cd;
      transition: width 0.4s ease, height 0.4s ease, top 0.4s ease, left 0.4s ease;
      z-index: -1;
    }

    .btn-expand-circle:hover::before {
      width: 300px;
      height: 300px;
      top: -100px;
      left: -100px;
    }

    /* 6. Scale Up */
    .btn-scale-up {
      background: #4e54c8;
      color: white;
      border-radius: 10px;
      transition: transform 0.3s ease, box-shadow 0.3s ease;
    }

    .btn-scale-up:hover {
      transform: scale(1.1);
      box-shadow: 0 10px 25px rgba(78, 84, 200, 0.4);
    }

    /* 7. Rotate */
    .btn-rotate {
      background: #ff5858;
      color: white;
      border-radius: 10px;
      transition: transform 0.5s ease;
    }

    .btn-rotate:hover {
      transform: rotate(5deg) scale(1.1);
    }

    /* 8. Neon Glow */
    .btn-neon {
      background: transparent;
      color: #00ff88;
      border: 2px solid #00ff88;
      border-radius: 50px;
      transition: all 0.3s ease;
    }

    .btn-neon:hover {
      color: #111;
      background: #00ff88;
      box-shadow: 0 0 20px #00ff88, 0 0 40px #00ff88, 0 0 60px #00ff88;
    }

    /* 9. Border Animation */
    .btn-border-anim {
      background: transparent;
      color: #667eea;
      border: 3px solid #667eea;
      border-radius: 10px;
      transition: all 0.3s ease;
    }

    .btn-border-anim:hover {
      background: #667eea;
      color: white;
      border-radius: 50px;
    }

    /* 10. Shine Effect */
    .btn-shine {
      background: #667eea;
      color: white;
      border-radius: 50px;
      position: relative;
    }

    .btn-shine::after {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 50%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255,255,255,0.5), transparent);
      transition: left 0.5s ease;
    }

    .btn-shine:hover::after {
      left: 100%;
    }

    /* 11. Split */
    .btn-split {
      background: transparent;
      color: #764ba2;
      border: 3px solid #764ba2;
      border-radius: 10px;
      position: relative;
    }

    .btn-split::before,
    .btn-split::after {
      content: '';
      position: absolute;
      width: 0;
      height: 100%;
      background: #764ba2;
      transition: width 0.3s ease;
      z-index: -1;
    }

    .btn-split::before {
      top: 0;
      left: 50%;
    }

    .btn-split::after {
      top: 0;
      right: 50%;
    }

    .btn-split:hover {
      color: white;
    }

    .btn-split:hover::before,
    .btn-split:hover::after {
      width: 51%;
    }

    /* 12. Bounce */
    .btn-bounce {
      background: #ff6b6b;
      color: white;
      border-radius: 50px;
      animation: none;
    }

    .btn-bounce:hover {
      animation: bounce 0.5s ease;
    }

    @keyframes bounce {
      0%, 100% { transform: translateY(0); }
      25% { transform: translateY(-10px); }
      50% { transform: translateY(0); }
      75% { transform: translateY(-5px); }
    }

    /* 13. Wobble */
    .btn-wobble {
      background: #00cec9;
      color: white;
      border-radius: 10px;
    }

    .btn-wobble:hover {
      animation: wobble 0.5s ease;
    }

    @keyframes wobble {
      0%, 100% { transform: rotate(0deg); }
      25% { transform: rotate(-5deg); }
      75% { transform: rotate(5deg); }
    }

    /* 14. Pulse */
    .btn-pulse {
      background: #feca57;
      color: #333;
      border-radius: 50px;
    }

    .btn-pulse:hover {
      animation: pulse 1s ease infinite;
    }

    @keyframes pulse {
      0%, 100% { transform: scale(1); }
      50% { transform: scale(1.05); }
    }

    /* 15. Shadow Drop */
    .btn-shadow {
      background: #667eea;
      color: white;
      border-radius: 10px;
      box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
      transition: all 0.3s ease;
    }

    .btn-shadow:hover {
      transform: translateY(-5px);
      box-shadow: 0 15px 30px rgba(102, 126, 234, 0.5);
    }

    /* 16. Outline to Filled */
    .btn-outline-fill {
      background: transparent;
      color: #ff6b6b;
      border: 3px solid #ff6b6b;
      border-radius: 50px;
      transition: all 0.3s ease;
    }

    .btn-outline-fill:hover {
      background: #ff6b6b;
      color: white;
    }

    /* 17. Gradient Shift */
    .btn-gradient-shift {
      background: linear-gradient(90deg, #667eea, #764ba2, #667eea);
      background-size: 200% auto;
      color: white;
      border-radius: 50px;
      transition: background-position 0.5s ease;
    }

    .btn-gradient-shift:hover {
      background-position: right center;
    }

    /* 18. 3D Push */
    .btn-3d-push {
      background: #00b894;
      color: white;
      border-radius: 10px;
      box-shadow: 0 8px 0 #007d63;
      transition: all 0.1s ease;
    }

    .btn-3d-push:hover {
      box-shadow: 0 4px 0 #007d63;
      transform: translateY(4px);
    }

    .btn-3d-push:active {
      box-shadow: 0 0 0 #007d63;
      transform: translateY(8px);
    }

    /* 19. Flip Horizontal */
    .btn-flip-h {
      background: #c471f5;
      color: white;
      border-radius: 10px;
      transition: transform 0.6s ease;
      transform-style: preserve-3d;
    }

    .btn-flip-h:hover {
      transform: rotateX(360deg);
    }

    /* 20. Flip Vertical */
    .btn-flip-v {
      background: #fa71cd;
      color: white;
      border-radius: 10px;
      transition: transform 0.6s ease;
      transform-style: preserve-3d;
    }

    .btn-flip-v:hover {
      transform: rotateY(360deg);
    }

    /* 21. Skew */
    .btn-skew {
      background: #4e54c8;
      color: white;
      border-radius: 10px;
      transition: transform 0.3s ease;
    }

    .btn-skew:hover {
      transform: skewX(-10deg);
    }

    /* 22. Double Border */
    .btn-double-border {
      background: transparent;
      color: #667eea;
      border: 3px solid #667eea;
      border-radius: 10px;
      position: relative;
      transition: all 0.3s ease;
    }

    .btn-double-border::before {
      content: '';
      position: absolute;
      top: -8px;
      left: -8px;
      right: -8px;
      bottom: -8px;
      border: 3px solid #764ba2;
      border-radius: 10px;
      opacity: 0;
      transition: opacity 0.3s ease;
    }

    .btn-double-border:hover {
      color: white;
      background: #667eea;
    }

    .btn-double-border:hover::before {
      opacity: 1;
    }

    /* 23. Neon Border */
    .btn-neon-border {
      background: #1a1a1a;
      color: #00ffff;
      border: 2px solid #00ffff;
      border-radius: 10px;
      transition: all 0.3s ease;
    }

    .btn-neon-border:hover {
      box-shadow: 
        0 0 10px #00ffff,
        0 0 20px #00ffff,
        inset 0 0 10px #00ffff;
    }

    /* 24. Corner Reveal */
    .btn-corner {
      background: #ff6b6b;
      color: white;
      border-radius: 10px;
      position: relative;
    }

    .btn-corner::before,
    .btn-corner::after {
      content: '';
      position: absolute;
      width: 0;
      height: 0;
      border: 2px solid white;
      transition: width 0.3s ease, height 0.3s ease;
    }

    .btn-corner::before {
      top: 0;
      left: 0;
      border-width: 2px 0 0 2px;
    }

    .btn-corner::after {
      bottom: 0;
      right: 0;
      border-width: 0 2px 2px 0;
    }

    .btn-corner:hover::before,
    .btn-corner:hover::after {
      width: 100%;
      height: 100%;
    }

    /* 25. Sweep to Right */
    .btn-sweep-right {
      background: linear-gradient(to right, #667eea 50%, #764ba2 50%);
      background-size: 200% 100%;
      background-position: left bottom;
      color: white;
      border-radius: 50px;
      transition: background-position 0.3s ease;
    }

    .btn-sweep-right:hover {
      background-position: right bottom;
    }

    /* 26. Icon Slide */
    .btn-icon-slide {
      background: #00b894;
      color: white;
      border-radius: 50px;
      display: inline-flex;
      align-items: center;
      gap: 10px;
    }

    .btn-icon-slide::after {
      content: '→';
      display: inline-block;
      transition: transform 0.3s ease;
    }

    .btn-icon-slide:hover::after {
      transform: translateX(5px);
    }

    /* 27. Loading Animation */
    .btn-loading {
      background: #667eea;
      color: white;
      border-radius: 50px;
      position: relative;
    }

    .btn-loading:hover::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 10px;
      width: 20px;
      height: 20px;
      border: 3px solid white;
      border-top-color: transparent;
      border-radius: 50%;
      animation: spin 0.8s linear infinite;
      margin-top: -10px;
    }

    @keyframes spin {
      to { transform: rotate(360deg); }
    }

    /* 28. Text Shadow */
    .btn-text-shadow {
      background: #764ba2;
      color: white;
      border-radius: 10px;
      transition: text-shadow 0.3s ease;
    }

    .btn-text-shadow:hover {
      text-shadow: 0 0 10px white, 0 0 20px white;
    }

    /* 29. Border Grow */
    .btn-border-grow {
      background: transparent;
      color: #ff6b6b;
      border: 2px solid #ff6b6b;
      border-radius: 10px;
      transition: border-width 0.3s ease, padding 0.3s ease;
    }

    .btn-border-grow:hover {
      border-width: 5px;
      padding: 12px 37px;
    }

    /* 30. Rainbow Border */
    .btn-rainbow {
      background: white;
      color: #333;
      border: 3px solid transparent;
      border-radius: 10px;
      background-clip: padding-box;
      position: relative;
    }

    .btn-rainbow::before {
      content: '';
      position: absolute;
      top: -3px;
      left: -3px;
      right: -3px;
      bottom: -3px;
      background: linear-gradient(45deg, red, orange, yellow, green, blue, indigo, violet);
      border-radius: 10px;
      z-index: -1;
      background-size: 400%;
      animation: rainbow 3s linear infinite;
    }

    @keyframes rainbow {
      to { background-position: 400%; }
    }

    footer {
      text-align: center;
      color: white;
      padding: 30px 20px;
      margin-top: 50px;
    }

    footer p {
      opacity: 0.9;
      font-size: 1rem;
      margin-bottom: 10px;
    }

    @media (max-width: 768px) {
      header h1 {
        font-size: 2rem;
      }

      .grid {
        grid-template-columns: 1fr;
        gap: 20px;
      }

      .button-card {
        padding: 30px;
        min-height: 180px;
      }

      .btn {
        padding: 12px 30px;
        font-size: 0.95rem;
      }
    }