:root {
    --black: #050505;
    --violet: #a259ff;
    --white: #ffffff;
    --gray: #121212;
    --gray-border: #222222;
    --violet-glow: rgba(162, 89, 255, 0.4); 
    --filter-violet: invert(43%) sepia(91%) saturate(3442%) hue-rotate(242deg) brightness(101%) contrast(106%);
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--black);
    color: var(--white);
    font-family: 'Inter', sans-serif;
    overflow-x: hidden;
    overflow-y: hidden;
    width: 100%;
}

/* HEADER EN BARRE LATÉRALE GAUCHE */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 80px;
    height: 100vh;
    padding: 50px 0;
    z-index: 1000;
    display: flex;
    flex-direction: column; 
    align-items: center;
    justify-content: space-between;
    background: rgba(5, 5, 5, 0.3); 
    backdrop-filter: blur(10px);
    border-right: 1px solid rgba(255, 255, 255, 0.05);
}

.logo-container {
    margin-top: 10px;
}

.logo {
    height: 45px;
    width: auto;
    filter: var(--filter-violet) drop-shadow(0 0 5px var(--violet-glow));
    transition: 0.3s ease;
}

.logo-link {
    text-decoration: none;
    display: inline-block;
    transition: transform 0.3s ease;
}

.logo-link:hover {
    transform: scale(1.05);
}

.nav-center {
    display: flex;
    flex-direction: column; 
    justify-content: center;
    gap: 40px;
    flex-grow: 1;
    width: 100%;
    align-items: center;
}

.nav-link {
    text-decoration: none;
    color: white;
    font-size: 0.9rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 3px;
    opacity: 0.4;
    transition: all 0.4s ease;
    display: flex;
    align-items: center; 
    justify-content: center;
    width: 60px;  
    height: 120px;
    writing-mode: vertical-rl;
    transform: rotate(180deg);
    border-left: 3px solid transparent;
    padding-right: 5px; 
}

.nav-link:hover {
    opacity: 1 !important;
    color: var(--violet) !important;
}

.nav-link.active {
    opacity: 1;
    color: var(--violet);
    border-left: 3px solid var(--violet);
    filter: drop-shadow(0 0 8px var(--violet-glow));
}

.bg-glow, .bg-shapes-extra {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    z-index: -1;
    overflow: hidden;
    pointer-events: none;
}

.bg-glow {
    background: radial-gradient(circle at var(--x, 50%) var(--y, 50%), rgba(162, 89, 255, 0.12) 0%, transparent 60%);
}

.bg-glow::before, 
.bg-glow::after,
.bg-shapes-extra::before,
.bg-shapes-extra::after {
    content: "";
    position: absolute;
    z-index: -2;
    animation: float-varied 20s infinite ease-in-out;
}

.bg-glow::before {
    width: 450px; height: 450px;
    top: -10%; right: -5%;
    border: 1px solid rgba(162, 89, 255, 0.12);
    border-radius: 50%;
    animation-duration: 35s;
}

.bg-glow::after {
    width: 180px; height: 180px;
    top: 40%; left: 5%;
    border: 1px solid rgba(162, 89, 255, 0.12);
    transform: rotate(15deg);
    animation-delay: -5s;
}

.bg-shapes-extra::before {
    content: "+";
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(162, 89, 255, 0.2);
    font-size: 4rem;
    font-weight: 100;
    top: 10%; left: 10%;
    animation-duration: 18s;
}

.bg-shapes-extra::after {
    content: "+";
    display: flex;
    align-items: center;
    justify-content: center;
    color: rgba(162, 89, 255, 0.2);
    font-size: 4rem;
    font-weight: 100;
    bottom: 15%; right: 10%;
    animation-duration: 15s;
    animation-delay: -2s;
}

.bg-shapes-extra {
    background-image: radial-gradient(circle, rgba(162, 89, 255, 0.05) 1px, transparent 1px);
    background-size: 50px 50px;
}

@keyframes float-varied {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    33% { transform: translate(20px, 40px) rotate(10deg); }
    66% { transform: translate(-30px, 15px) rotate(-5deg); }
}

@media (max-width: 1024px) {
    .main-header {
        width: 100%;
        height: 60px;
        flex-direction: row;
        padding: 0 20px;
        left: 0;
        border-right: none;
        border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    }

    .menu-burger {
        display: flex;
        flex-direction: column;
        gap: 5px;
        cursor: pointer;
        position: relative;
        z-index: 1002;
    }

    .menu-burger span {
        width: 24px;
        height: 2px;
        background: var(--white);
        transition: 0.3s;
    }

    .menu-burger.toggle span:nth-child(1) { transform: rotate(-45deg) translate(-5px, 5px); }
    .menu-burger.toggle span:nth-child(2) { opacity: 0; }
    .menu-burger.toggle span:nth-child(3) { transform: rotate(45deg) translate(-5px, -5px); }

    .nav-center {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        height: 100vh;
        background: rgba(5, 5, 5, 0.9); 
        box-shadow: -10px 0 30px rgba(0, 0, 0, 0.5); 
        backdrop-filter: blur(15px);
        flex-direction: column;
        transition: 0.4s ease;
        z-index: 999;
    }

    .nav-center.active { right: 0; }

    .nav-link {
        writing-mode: horizontal-tb;
        transform: rotate(0);
        width: 100%;
        font-size: 1.2rem;
        padding: 20px;
        border-left: none;
    }
}

@media (min-width: 1025px) {
    .menu-burger {
        display: none;
    }
}