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

body,
html {
    height: 100%;
    width: 100%;
    font-family: 'Space Grotesk', sans-serif;
    color: white;
    overflow: hidden;
}

/* Фоновое изображение + видео */
#bg-video,
#bg-placeholder {
    position: fixed;
    top: 50%;
    left: 50%;
    width: 100vw;
    height: 100vh;
    min-width: 100vw;
    min-height: 100vh;
    transform: translate(-50%, -50%);
    object-fit: cover;
}

#bg-video {
    z-index: -2;
    opacity: 0;
    transition: opacity 0.4s ease;
}

#bg-video.is-visible {
    opacity: 1;
}

#bg-placeholder {
    z-index: -3;
    transition: opacity 0.4s ease;
}

#bg-placeholder.is-hidden {
    opacity: 0;
    visibility: hidden;
}

.header {
  position: absolute;
  bottom: 20%;
  left: 50%;
  transform: translate(-50%, -50%);
  text-align: center;
  color: white;
  z-index: 10;
}

.header h1 {
    font-size: clamp(48px, 3.5vw, 72px);
    font-weight: 300;
    letter-spacing: -0.02em;
    margin-bottom: 2rem;
    animation: titleGlow 4s ease-in-out infinite alternate;
    text-transform: uppercase;
}

@keyframes titleGlow {
    0% {
        text-shadow:
            0 0 20px rgba(255, 255, 255, 0.1),
            0 2px 4px rgba(0, 0, 0, 0.8);
    }

    100% {
        text-shadow:
            0 0 30px rgba(255, 255, 255, 0.2),
            0 2px 8px rgba(0, 0, 0, 0.6);
    }
}

.enter-portfolio {
    display: inline-block;
    text-decoration: none;
    padding: 1rem 2.5rem;
    border: 2px solid rgba(255, 255, 255, 0.3);
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    color: white;
    font-size: clamp(1rem, 3vw, 1.5rem);
    font-weight: 400;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    position: fixed;
    bottom: 20%;
    left: 50%;
    overflow: hidden;
    border-radius: 2px;
    z-index: 9999; 
    transform: translateX(-50%);
}

.enter-portfolio::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 0.6s ease;
}

.enter-portfolio:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: rgba(255, 255, 255, 0.6);
    transform: translateX(-50%) translateY(-2px);
    box-shadow:
        0 10px 30px rgba(0, 0, 0, 0.3),
        0 0 0 1px rgba(255, 255, 255, 0.1);
}

.enter-portfolio:hover::before {
    left: 100%;
}

.enter-portfolio:active {
    transform: translateX(-50%) translateY(0);
}

/* Адаптивность для мобильных устройств */
@media (max-width: 768px) {
    body {
        cursor: auto;
    }

    body::before {
        display: none;
    }

    .header h1 {
        font-size: clamp(2rem, 10vw, 3.5rem);
        margin-bottom: 1.5rem;
    }

    .enter-portfolio {
        font-size: clamp(0.9rem, 4vw, 1.2rem);
        padding: 0.8rem 2rem;
    }
}

@media (max-width: 480px) {
    .header h1 {
        letter-spacing: -0.01em;
    }
}

/* Улучшения для доступности */
@media (prefers-reduced-motion: reduce) {
    .header h1 {
        animation: none;
    }

    .enter-portfolio,
    .links a {
        transition: none;
    }

    .enter-portfolio::before {
        display: none;
    }
}

/* Эффект при загрузке страницы */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translate(-50%, -40%);
    }

    to {
        opacity: 1;
        transform: translate(-50%, -50%);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }

    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.header {
    animation: fadeInUp 1.2s ease-out;
}