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

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
      background: radial-gradient(ellipse at top, #1e1b4b, #0f0c29, #24243e);
      min-height: 100vh;
      display: flex;
      justify-content: center;
      align-items: center;
      padding: 20px;
      overflow-x: hidden;
      position: relative;
    }

    /* Animated background particles */
    .particles {
      position: absolute;
      width: 100%;
      height: 100%;
      overflow: hidden;
      z-index: 0;
    }

    .particle {
      position: absolute;
      background: rgba(255, 255, 255, 0.1);
      border-radius: 50%;
      animation: float 8s infinite ease-in-out;
    }

    @keyframes float {
      0%, 100% {
        transform: translateY(0) rotate(0deg);
        opacity: 0.3;
      }
      50% {
        transform: translateY(-20px) rotate(180deg);
        opacity: 0.8;
      }
    }

    .container {
      background: rgba(255, 255, 255, 0.03);
      backdrop-filter: blur(25px);
      border-radius: 35px;
      padding: 50px 40px;
      box-shadow: 
        0 30px 80px rgba(0, 0, 0, 0.3),
        inset 0 1px 0 rgba(255, 255, 255, 0.1),
        0 0 100px rgba(139, 92, 246, 0.1);
      text-align: center;
      max-width: 480px;
      width: 100%;
      border: 1px solid rgba(255, 255, 255, 0.08);
      position: relative;
      z-index: 1;
      transition: all 0.3s ease;
    }

    .container::before {
      content: '';
      position: absolute;
      top: -2px;
      left: -2px;
      right: -2px;
      bottom: -2px;
      background: linear-gradient(45deg, #8b5cf6, #06b6d4, #10b981, #f59e0b, #ef4444, #8b5cf6);
      border-radius: 37px;
      z-index: -1;
      background-size: 300% 300%;
      animation: gradientShift 6s ease infinite;
      opacity: 0;
      transition: opacity 0.3s ease;
    }

    .container.running::before {
      opacity: 0.6;
    }

    @keyframes gradientShift {
      0%, 100% { background-position: 0% 50%; }
      50% { background-position: 100% 50%; }
    }

    .header {
      margin-bottom: 40px;
    }

    h1 {
      color: #ffffff;
      font-size: 3rem;
      font-weight: 800;
      margin-bottom: 10px;
      text-shadow: 0 0 30px rgba(139, 92, 246, 0.5);
      background: linear-gradient(135deg, #8b5cf6, #06b6d4);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      animation: titleGlow 3s ease-in-out infinite alternate;
    }

    @keyframes titleGlow {
      from {
        filter: drop-shadow(0 0 20px rgba(139, 92, 246, 0.3));
      }
      to {
        filter: drop-shadow(0 0 30px rgba(6, 182, 212, 0.4));
      }
    }

    .subtitle {
      color: rgba(255, 255, 255, 0.6);
      font-size: 1rem;
      font-weight: 500;
      letter-spacing: 2px;
      text-transform: uppercase;
    }

    .time-display {
      padding: 40px 30px;
      margin-bottom: 40px;
      position: relative;
      overflow: hidden;
    }

    .time-display::before {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
      transition: left 2s ease;
    }

    .running .time-display::before {
      animation: shimmer 3s infinite;
    }

    @keyframes shimmer {
      0% { left: -100%; }
      100% { left: 100%; }
    }

    .mainDiv {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 15px;
      font-family: 'SF Mono', Monaco, 'Cascadia Code', monospace;
      font-size: 4rem;
      font-weight: 700;
      color: #ffffff;
      text-shadow: 0 0 30px rgba(255, 255, 255, 0.3);
      position: relative;
    }

    .time-unit {
      padding: 10px 5px;
      min-width: auto;
      transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
      position: relative;
      overflow: visible;
      background: transparent;
    }

    .time-unit::before {
      content: '';
      position: absolute;
      top: 50%;
      left: 50%;
      width: 120px;
      height: 120px;
      background: radial-gradient(circle, rgba(139, 92, 246, 0.15), transparent 70%);
      opacity: 0;
      transition: all 0.4s ease;
      border-radius: 50%;
      transform: translate(-50%, -50%) scale(0);
      pointer-events: none;
    }

    .running .time-unit::before {
      opacity: 1;
      transform: translate(-50%, -50%) scale(1);
      animation: floatingGlow 3s infinite ease-in-out alternate;
    }

    @keyframes floatingGlow {
      0% {
        transform: translate(-50%, -50%) scale(1);
        opacity: 0.4;
        filter: blur(10px);
      }
      100% {
        transform: translate(-50%, -50%) scale(1.2);
        opacity: 0.8;
        filter: blur(15px);
      }
    }

    .time-unit span {
      position: relative;
      z-index: 1;
    }

    .separator {
      font-size: 3rem;
      background: linear-gradient(135deg, #8b5cf6, #06b6d4);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      font-weight: bold;
      animation: pulse 1.5s infinite;
      text-shadow: 0 0 20px rgba(139, 92, 246, 0.5);
    }

    @keyframes pulse {
      0%, 100% { 
        opacity: 1; 
        transform: scale(1);
      }
      50% { 
        opacity: 0.6; 
        transform: scale(1.1);
      }
    }

    .time-labels {
      display: flex;
      justify-content: center;
      gap: 100px;
      margin-top: 25px;
      font-size: 0.85rem;
      color: rgba(255, 255, 255, 0.5);
      font-weight: 600;
      letter-spacing: 2px;
      text-transform: uppercase;
    }

    .controls {
      display: flex;
      gap: 20px;
      justify-content: center;
      flex-wrap: wrap;
      margin-bottom: 30px;
    }

    button {
      padding: 18px 35px;
      border: none;
      border-radius: 25px;
      font-size: 1.1rem;
      font-weight: 600;
      cursor: pointer;
      transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
      min-width: 120px;
      position: relative;
      overflow: hidden;
      text-transform: uppercase;
      letter-spacing: 1px;
      font-family: inherit;
      backdrop-filter: blur(10px);
      border: 1px solid rgba(255, 255, 255, 0.2);
    }

    button::before {
      content: '';
      position: absolute;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100%;
      background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
      transition: left 0.6s;
    }

    button:hover:not(:disabled)::before {
      left: 100%;
    }

    .btn-start {
      background: linear-gradient(135deg, #10b981, #059669);
      color: white;
      box-shadow: 0 10px 30px rgba(16, 185, 129, 0.4);
    }

    .btn-start:hover:not(:disabled) {
      background: linear-gradient(135deg, #059669, #047857);
      transform: translateY(-3px);
      box-shadow: 0 15px 40px rgba(16, 185, 129, 0.5);
    }

    .btn-start:disabled {
      background: linear-gradient(135deg, #374151, #1f2937);
      cursor: not-allowed;
      transform: none;
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    }

    .btn-stop {
      background: linear-gradient(135deg, #ef4444, #dc2626);
      color: white;
      box-shadow: 0 10px 30px rgba(239, 68, 68, 0.4);
    }

    .btn-stop:hover {
      background: linear-gradient(135deg, #dc2626, #b91c1c);
      transform: translateY(-3px);
      box-shadow: 0 15px 40px rgba(239, 68, 68, 0.5);
    }

    .btn-reset {
      background: linear-gradient(135deg, #8b5cf6, #7c3aed);
      color: white;
      box-shadow: 0 10px 30px rgba(139, 92, 246, 0.4);
    }

    .btn-reset:hover {
      background: linear-gradient(135deg, #7c3aed, #6d28d9);
      transform: translateY(-3px);
      box-shadow: 0 15px 40px rgba(139, 92, 246, 0.5);
    }

    .btn-lap {
      background: linear-gradient(135deg, #f59e0b, #d97706);
      color: white;
      box-shadow: 0 10px 30px rgba(245, 158, 11, 0.4);
    }

    .btn-lap:hover:not(:disabled) {
      background: linear-gradient(135deg, #d97706, #b45309);
      transform: translateY(-3px);
      box-shadow: 0 15px 40px rgba(245, 158, 11, 0.5);
    }

    .btn-lap:disabled {
      background: linear-gradient(135deg, #374151, #1f2937);
      cursor: not-allowed;
      transform: none;
      box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    }

    button:active:not(:disabled) {
      transform: translateY(1px);
    }

    button i {
      margin-right: 8px;
    }

    /* Lap Times */
    .lap-times {
      max-height: 300px;
      overflow-y: auto;
      margin-top: 20px;
      background: rgba(255, 255, 255, 0.02);
      border-radius: 15px;
      padding: 20px;
      border: 1px solid rgba(255, 255, 255, 0.05);
    }

    .lap-times:empty {
      display: none;
    }

    .lap-times h3 {
      color: rgba(255, 255, 255, 0.8);
      margin-bottom: 15px;
      font-size: 1.2rem;
      text-align: left;
    }

    .lap-item {
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 12px 15px;
      margin-bottom: 8px;
      background: rgba(255, 255, 255, 0.03);
      border-radius: 10px;
      color: rgba(255, 255, 255, 0.9);
      border-left: 3px solid #8b5cf6;
      transition: all 0.3s ease;
    }

    .lap-item:hover {
      background: rgba(255, 255, 255, 0.05);
      transform: translateX(5px);
    }

    .lap-number {
      font-weight: 600;
      color: #8b5cf6;
    }

    .lap-time {
      font-family: 'SF Mono', Monaco, monospace;
      font-weight: 500;
    }

    /* Sound toggle */
    .sound-toggle {
      position: absolute;
      top: 20px;
      right: 20px;
      background: rgba(255, 255, 255, 0.1);
      border: 1px solid rgba(255, 255, 255, 0.2);
      border-radius: 50%;
      width: 50px;
      height: 50px;
      display: flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      transition: all 0.3s ease;
      color: rgba(255, 255, 255, 0.7);
    }

    .sound-toggle:hover {
      background: rgba(255, 255, 255, 0.2);
      color: white;
      transform: scale(1.1);
    }

    .sound-toggle.muted {
      color: #ef4444;
    }

    /* Mobile responsiveness */
    @media (max-width: 580px) {
      .container {
        padding: 40px 25px;
        margin: 10px;
        max-width: 95%;
      }

      h1 {
        font-size: 2.5rem;
        margin-bottom: 8px;
      }

      .subtitle {
        font-size: 0.85rem;
      }

      .mainDiv {
        font-size: 3rem;
        gap: 10px;
      }

      .time-unit {
        min-width: auto;
        padding: 8px 3px;
      }

      .time-labels {
        gap: 80px;
        font-size: 0.75rem;
        letter-spacing: 1px;
      }

      .controls {
        gap: 12px;
        margin-bottom: 25px;
      }

      button {
        padding: 15px 25px;
        font-size: 0.95rem;
        min-width: 100px;
      }

      .sound-toggle {
        width: 45px;
        height: 45px;
        top: 15px;
        right: 15px;
      }
    }

    /* Scrollbar styling */
    .lap-times::-webkit-scrollbar {
      width: 6px;
    }

    .lap-times::-webkit-scrollbar-track {
      background: rgba(255, 255, 255, 0.05);
      border-radius: 3px;
    }

    .lap-times::-webkit-scrollbar-thumb {
      background: rgba(139, 92, 246, 0.5);
      border-radius: 3px;
    }

    .lap-times::-webkit-scrollbar-thumb:hover {
      background: rgba(139, 92, 246, 0.7);
    }

    /* Achievement notification */
    .achievement {
      position: fixed;
      top: 30px;
      right: 30px;
      background: linear-gradient(135deg, #10b981, #059669);
      color: white;
      padding: 15px 25px;
      border-radius: 15px;
      box-shadow: 0 15px 35px rgba(16, 185, 129, 0.4);
      transform: translateX(400px);
      transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
      z-index: 1000;
      border: 1px solid rgba(255, 255, 255, 0.2);
    }

    .achievement.show {
      transform: translateX(0);
    }

    .achievement i {
      margin-right: 10px;
      color: #fbbf24;
    }