:root {
    --bg-primary: hsl(0, 0%, 85%);
    --bg-secondary: hsl(0, 0%, 95%);
    --bg-tertiary: hsl(210, 14%, 90%);
    --text-primary: hsl(210, 29%, 20%);
    --text-secondary: hsl(0, 0%, 30%);
    --accent-color: hsl(204, 70%, 45%);
    --nav-bg: hsl(210, 29%, 20%);
    --nav-button: hsl(210, 29%, 18%);
    --nav-button-hover: hsl(210, 29%, 25%);
    --shadow-color: hsla(0, 0%, 0%, 0.1);
    --card-border: transparent;
  }
  
  [data-theme="dark"] {
    --bg-primary: hsl(210, 15%, 15%);
    --bg-secondary: hsl(210, 15%, 20%);
    --bg-tertiary: hsl(210, 15%, 25%);
    --text-primary: hsl(0, 0%, 90%);
    --text-secondary: hsl(0, 0%, 70%);
    --accent-color: hsl(204, 70%, 55%);
    --nav-bg: hsl(210, 15%, 10%);
    --nav-button: hsl(210, 15%, 25%);
    --nav-button-hover: hsl(210, 15%, 35%);
    --shadow-color: hsla(0, 0%, 0%, 0.3);
    --card-border: hsl(210, 15%, 30%);
  }
  
  * {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
  }
  
  body {
    font-family: 'Poppins', Arial, sans-serif;
    line-height: 1.6;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    overflow-x: hidden;
  }
  
  .theme-toggle {
    position: fixed;
    top: 13px;
    right: 20px;
    background-color: var(--accent-color);
    color: white;
    border: none;
    border-radius: 50%;
    width: 45px;
    height: 45px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 1000;
    box-shadow: 0 2px 10px var(--shadow-color);
    transition: transform 0.3s ease, background-color 0.3s;
  }
  
  .theme-toggle:hover {
    transform: rotate(30deg);
  }
  
  .theme-toggle i {
    font-size: 1.5rem;
  }

  .navbar {
    background-color: var(--nav-bg);
    padding: 1rem;
    display: flex;
    justify-content: center;
    gap: 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 15px var(--shadow-color);
  }
  
  .nav-button {
    padding: 0.75rem 1.5rem;
    width: 20%;
    justify-content: space-around;
    border: none;
    border-radius: 4px;
    background-color: var(--nav-button);
    color: white;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 500;
    letter-spacing: 0.5px;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    position: relative;
    overflow: hidden;
  }
  
  .nav-button:hover {
    background-color: var(--nav-button-hover);
    transform: translateY(-2px);
  }
  
  .nav-button:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background-color: var(--accent-color);
    transform: scaleX(0);
    transform-origin: bottom right;
    transition: transform 0.3s ease-out;
  }
  
  .nav-button:hover:after {
    transform-origin: bottom left;
    transform: scaleX(1);
  }
  
  .nav-button.active {
    background-color: var(--accent-color);
    transform: translateY(0);
  }
  
  .nav-button.active:after {
    transform: scaleX(1);
  }
  
  main {
    max-width: 1200px;
    margin: 2rem auto;
    padding: 0 1rem;
  }
  
  .content {
    display: none;
    background-color: var(--bg-secondary);
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 10px 30px var(--shadow-color);
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
  }
  
  .content.active {
    display: block;
    opacity: 1;
    transform: translateY(0);
    animation: fadeIn 0.5s ease forwards;
  }
  
  @keyframes fadeIn {
    0% {
      opacity: 0;
      transform: translateY(20px);
    }
    100% {
      opacity: 1;
      transform: translateY(0);
    }
  }
  
  h1 {
    color: var(--text-primary);
    margin-bottom: 1.5rem;
    position: relative;
    display: inline-block;
  }
  
  h1:after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 0;
    width: 60px;
    height: 4px;
    background-color: var(--accent-color);
    border-radius: 2px;
  }
  
  p {
    margin-bottom: 1rem;
    color: var(--text-secondary);
  }
  
  .upcoming-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
  }
  
  .upcoming-item {
    padding: 1.5rem;
    background-color: var(--bg-tertiary);
    border-radius: 8px;
    border-left: 4px solid var(--accent-color);
    box-shadow: 0 4px 15px var(--shadow-color);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
  }
  
  .upcoming-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px var(--shadow-color);
  }
  
  .upcoming-item h3 {
    color: var(--text-primary);
    margin-bottom: 0.5rem;
    font-weight: 600;
  }
  
  .video-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
  }
  
  .video-card {
    margin: 15px;
    grid-template-columns: repeat(4, 1fr);
    background-color: var(--bg-tertiary);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 15px var(--shadow-color);
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    text-decoration: none;
    color: inherit;
    display: block;
    position: relative;
    border: 1px solid var(--card-border);
  }
  
  .video-card:hover {
    scale: 1.01;
    transform: translateY(-8px);
    box-shadow: 0 15px 30px var(--shadow-color);
  }
  
  .video-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--accent-color);
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: 1;
    pointer-events: none;
  }
  
  .video-card:hover::before {
    opacity: 0.05;
  }
  
  [class^="video-thumbnail"] {
    height: 180px;
    background-color: #ddd;
    background-size: cover;
    background-repeat: no-repeat;
    background-position: center;
    position: relative;
    overflow: hidden;
  }
  
  [class^="video-thumbnail"]::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    width: 60px;
    height: 60px;
    background-color: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    opacity: 0;
    transition: all 0.3s ease;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='%23000'%3E%3Cpath d='M8 5v14l11-7z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: center;
    background-size: 30px;
  }
  
  .video-card:hover [class^="video-thumbnail"]::after {
    transform: translate(-50%, -50%) scale(1);
    opacity: 0.8;
  }
  
  .video-card h3 {
    padding: 1rem 1rem 0.5rem;
    color: var(--text-primary);
    font-size: 1rem;
    font-weight: 600;
  }
  
  .video-card p {
    padding: 0 1rem 1.2rem;
    color: var(--text-secondary);
    font-size: 0.9rem;
    display: -webkit-box;
    line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
    height: 4.5rem;
  }
  .video-thumbnail-n {background-image: url(zdj/nnn.png);}
  .video-thumbnail-k {background-image: url(zdj/kadr.png);}
.video-thumbnail1 {background-image: url(zdj/logo2.png);}
.video-thumbnail2 {background-image: url(zdj/logo1.png);}
.video-thumbnail3 {background-image: url(zdj/logo3.png);}
.video-thumbnail4 {background-image: url(zdj/logo4.png);}
.video-thumbnail5 {background-image: url(zdj/logo5.png);}
.video-thumbnail6 {background-image: url(zdj/logo6.png);}
.video-thumbnail7 {background-image: url(zdj/logo7.png);}
.video-thumbnail8 {background-image: url(zdj/logo8.png);}
.video-thumbnail9 {background-image: url(zdj/logo9.png);}
.video-thumbnail10 {background-image: url(zdj/logo10.png);}
.video-thumbnail11{background-image: url(zdj/logo11.png);}
.video-thumbnail12 {background-image: url(zdj/logo12.png)}
.video-thumbnail13 {background-image: url(zdj/logo13.png);}
.video-thumbnail14 {background-image: url(zdj/logo14.png);}
.video-thumbnail15 {background-image: url(zdj/logo15.png);}
.video-thumbnail16 {background-image: url(zdj/logo16.png);}
.video-thumbnail17 {background-image: url(zdj/logo17.png);}
.video-thumbnail18 {background-image: url(zdj/logo18.png);}
.video-thumbnail19 {background-image: url(zdj/logo19.png);}
.video-thumbnail20 {background-image: url(zdj/logo20.png);}
.video-thumbnail21 {background-image: url(zdj/logo21.png);}
.video-thumbnail22 {background-image: url(zdj/logo99.png);}
.video-thumbnail23 {background-image: url(zdj/logo23.png);}
.video-thumbnail24 {background-image: url(zdj/logo24.png);}
.video-thumbnail25 {background-image: url(zdj/logo25.png);}
.video-thumbnail26 {background-image: url(zdj/logo26.png);}
.video-thumbnail27 {background-image: url(zdj/logo27.png);}
.video-thumbnail28 {background-image: url(zdj/logo28.png);}
.video-thumbnail29 {background-image: url(zdj/logo100.png);}
.video-thumbnail-dsa {background-image: url(zdj/s.jpg.png);}
.video-thumbnail-d {background-image: url(zdj/milosz.png);}
.video-thumbnail-niger {background-image: url(zdj/norbert.png);}
.video-thumbnail-siema {background-image: url(zdj/siema.png);}
.video-thumbnail-game {background-image: url(zdj/jpg-game.jpg);}
.video-thumbnail-5 {background-image: url(zdj/pios.png);}
.video-thumbnail-wiedzmin {background-image: url(zdj/jpg-wiedzmin.jpg);}
.video-thumbnail-walentynki {background-image: url(zdj/jpg-walentynki.jpg);}
.video-thumbnail-2121 {background-image: url(zdj/Zrzut\ ekranu\ 2025-04-09\ 203226.png);}
.video-thumbnail-s {background-image: url(zdj/zdjzstr.png);}

.video-card:nth-child(1) { animation-delay: 0.1s; }
.video-card:nth-child(2) { animation-delay: 0.15s; }
.video-card:nth-child(3) { animation-delay: 0.2s; }
.video-card:nth-child(4) { animation-delay: 0.25s; }
.video-card:nth-child(5) { animation-delay: 0.3s; }
.video-card:nth-child(6) { animation-delay: 0.35s; }
.video-card:nth-child(7) { animation-delay: 0.4s; }
.video-card:nth-child(8) { animation-delay: 0.45s; }
.video-card:nth-child(9) { animation-delay: 0.5s; }
.video-card:nth-child(10) { animation-delay: 0.55s; }
.video-card:nth-child(11) { animation-delay: 0.6s; }
.video-card:nth-child(12) { animation-delay: 0.65s; }
.video-card:nth-child(13) { animation-delay: 0.7s; }
.video-card:nth-child(14) { animation-delay: 0.75s; }

.upcoming-item:nth-child(1) { animation-delay: 0.1s; }
.upcoming-item:nth-child(2) { animation-delay: 0.2s; }

@media (max-width: 768px) {
    .navbar {
      flex-direction: column;
      align-items: stretch;
      padding: 0.8rem;
    }
    
    .nav-button {
      width: 100%;
      text-align: center;
      margin-bottom: 0.5rem;
    }
    
    .content {
      padding: 1.5rem;
    }
    
    .video-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 1.5rem;
    }
    
    .theme-toggle {
      top: 10px;
      right: 10px;
      width: 40px;
      height: 40px;
    }

}



  @keyframes pulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
  }
  
  @keyframes slideInFromLeft {
    0% { transform: translateX(-30px); opacity: 0; }
    100% { transform: translateX(0); opacity: 1; }
  }
  
  .animated-item {
    animation: slideInFromLeft 0.5s forwards;
    opacity: 0;
  }
  
  .video-card {
    opacity: 0;
    animation: fadeIn 0.5s ease forwards;
  }