*{
    margin:0;
    padding:0;
    box-sizing:border-box;
    font-family:Arial, Helvetica, sans-serif;
}

html{
    scroll-behavior:smooth;
}

:root{
    --bg-primary:#121417;
    --bg-secondary:#181C20;
    --bg-card:#20252B;
    --border-color:rgba(255,255,255,0.08);
    --text-primary:#F5F7FA;
    --text-secondary:#B8C0CC;
    --grid-opacity:0.02;
    --card-hover-shadow:rgba(0,0,0,0.4);
    --photo-shadow:rgba(0,0,0,0.4);
    --btn-bg:rgba(255,255,255,0.08);
    --btn-border:rgba(255,255,255,0.25);
    --btn-hover-bg:rgba(255,255,255,0.12);
    --btn-hover-border:rgba(255,255,255,0.35);
    --btn-shadow:rgba(0,0,0,0.3);
    --nav-link-color:#B8C0CC;
    --nav-link-hover:#F5F7FA;
    --footer-bg:#181C20;
    --card-image-bg:#181C20;
    --transition-speed:0.3s;
}

[data-theme="dark"]{
    --bg-primary:#121417;
    --bg-secondary:#181C20;
    --bg-card:#20252B;
    --border-color:rgba(255,255,255,0.08);
    --text-primary:#F5F7FA;
    --text-secondary:#B8C0CC;
    --grid-opacity:0.02;
    --card-hover-shadow:rgba(0,0,0,0.4);
    --photo-shadow:rgba(0,0,0,0.4);
    --btn-bg:rgba(255,255,255,0.08);
    --btn-border:rgba(255,255,255,0.25);
    --btn-hover-bg:rgba(255,255,255,0.12);
    --btn-hover-border:rgba(255,255,255,0.35);
    --btn-shadow:rgba(0,0,0,0.3);
    --nav-link-color:#B8C0CC;
    --nav-link-hover:#F5F7FA;
    --footer-bg:#181C20;
    --card-image-bg:#181C20;
}

[data-theme="light"]{
    --bg-primary:#F5F7FA;
    --bg-secondary:#E8EBF0;
    --bg-card:#FFFFFF;
    --border-color:rgba(0,0,0,0.08);
    --text-primary:#1A1D23;
    --text-secondary:#5A6270;
    --grid-opacity:0.03;
    --card-hover-shadow:rgba(0,0,0,0.15);
    --photo-shadow:rgba(0,0,0,0.2);
    --btn-bg:rgba(0,0,0,0.05);
    --btn-border:rgba(0,0,0,0.15);
    --btn-hover-bg:rgba(0,0,0,0.1);
    --btn-hover-border:rgba(0,0,0,0.25);
    --btn-shadow:rgba(0,0,0,0.15);
    --nav-link-color:#5A6270;
    --nav-link-hover:#1A1D23;
    --footer-bg:#E8EBF0;
    --card-image-bg:#F0F2F5;
}

body{
    background:transparent;
    color:var(--text-primary);
    line-height:1.6;
    overflow-x:hidden;
    position:relative;
    transition:color var(--transition-speed) ease;
}

/* ================= PHOTO OVERLAY ================= */

.photo-overlay{
    position:fixed;
    top:0;
    left:0;
    width:100%;
    height:100%;
    background:rgba(0,0,0,0.9);
    z-index:10000;
    display:flex;
    align-items:center;
    justify-content:center;
    opacity:0;
    visibility:hidden;
    pointer-events:none;
    transition:opacity 0.5s ease, visibility 0s linear 0.5s;
}

.photo-overlay.active{
    opacity:1;
    visibility:visible;
    pointer-events:auto;
    transition:opacity 0.5s ease;
}

.overlay-photo{
    max-width:90%;
    max-height:90%;
    object-fit:contain;
    border-radius:10px;
    box-shadow:0 20px 60px rgba(0,0,0,0.5);
    opacity:0;
    transform:scale(0.5);
    transition:transform 1.3s linear, opacity 1.3s linear;
}

.photo-overlay.active .overlay-photo{
    opacity:1;
    transform:scale(1);
}

/* ================= HEADER ================= */

header{
    position:fixed;
    top:0;
    left:0;
    width:100%;
    background:rgba(18,20,23,.85);
    backdrop-filter:blur(20px);
    border-bottom:1px solid var(--border-color);
    z-index:1000;
    transition:border-color var(--transition-speed) ease;
}

[data-theme="light"] header{
    background:rgba(245,247,250,.85);
}

nav{
    max-width:1200px;
    margin:auto;
    height:90px;
    display:flex;
    justify-content:space-between;
    align-items:center;
    padding:0 30px;
}

.logo{
    display:flex;
    align-items:center;
    gap:12px;
    font-size:20px;
    font-weight:700;
    letter-spacing:2.5px;
    color:var(--text-primary);
    transition:color var(--transition-speed) ease;
    white-space:nowrap;
}

.nav-profile-photo{
    width:36px;
    height:36px;
    border-radius:50%;
    object-fit:cover;
    border:2px solid var(--border-color);
    box-shadow:0 2px 8px var(--photo-shadow);
    flex-shrink:0;
    cursor:pointer;
    transition:transform 0.2s ease, box-shadow 0.2s ease;
}

.nav-profile-photo:hover{
    transform:scale(1.05);
    box-shadow:0 4px 12px var(--photo-shadow);
}

nav ul{
    display:flex;
    align-items:center;
    list-style:none;
    gap:40px;
}

nav a{
    color:var(--nav-link-color);
    text-decoration:none;
    transition:.3s ease;
    font-size:15px;
    position:relative;
}

nav a:hover{
    color:var(--nav-link-hover);
}

nav a::after{
    content:"";
    position:absolute;
    bottom:-4px;
    left:0;
    width:0;
    height:2px;
    background:rgba(255,255,255,.3);
    transition:.3s ease;
}

[data-theme="light"] nav a::after{
    background:rgba(0,0,0,.2);
}

nav a:hover::after{
    width:100%;
}

nav a.active{
    color:var(--nav-link-hover);
}

.nav-cv{
    padding:12px 22px;
    border:1px solid var(--btn-border);
    border-radius:30px;
    color:var(--text-primary);
    transition:border-color var(--transition-speed) ease, background var(--transition-speed) ease, color var(--transition-speed) ease;
}

.nav-cv:hover{
    background:var(--btn-hover-bg);
    color:var(--text-primary);
    border-color:var(--btn-hover-border);
}

/* ================= THEME TOGGLE ================= */

.theme-toggle{
    display:flex;
    align-items:center;
    gap:8px;
    padding:8px 16px;
    border:1px solid var(--btn-border);
    border-radius:30px;
    background:var(--btn-bg);
    cursor:pointer;
    transition:all .3s ease;
    position:relative;
}

.theme-toggle:hover{
    background:var(--btn-hover-bg);
    border-color:var(--btn-hover-border);
}

.theme-toggle svg{
    width:20px;
    height:20px;
    transition:transform .3s ease;
}

.theme-toggle .sun-icon,
.theme-toggle .moon-icon{
    color:var(--text-primary);
    transition:color var(--transition-speed) ease;
}

.theme-toggle .sun-icon{
    display:none;
}

.theme-toggle .moon-icon{
    display:block;
}

[data-theme="light"] .theme-toggle .sun-icon{
    display:block;
}

[data-theme="light"] .theme-toggle .moon-icon{
    display:none;
}

.theme-toggle:hover svg{
    transform:rotate(15deg);
}

/* ================= ACTIVE MENU ================= */

nav a.active{
    color:var(--nav-link-hover);
}

/* ================= HERO ================= */

.hero{
    min-height:65vh;
    display:flex;
    justify-content:center;
    align-items:center;
    padding:80px 30px 30px;
    position:relative;
    overflow:hidden;
}

.grid-bg{
    position:fixed;
    top:0;
    left:0;
    width:100%;
    height:100%;
    z-index:-1;
    background-color:var(--bg-primary);
    background-image:
        linear-gradient(rgba(255,255,255,var(--grid-opacity)) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,var(--grid-opacity)) 1px, transparent 1px);
    background-size:50px 50px;
    transition:background-color var(--transition-speed) ease, background-image var(--transition-speed) ease;
}

[data-theme="light"] .grid-bg{
    background-color:var(--bg-primary);
    background-image:
        linear-gradient(rgba(0,0,0,var(--grid-opacity)) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0,0,0,var(--grid-opacity)) 1px, transparent 1px);
}

.hero-content{
    width:100%;
    max-width:1200px;
    display:flex;
    flex-direction:column;
    align-items:center;
    text-align:center;
    position:relative;
    z-index:2;
    will-change:opacity, transform;
}

.hero-content > .hero-text{
    will-change:opacity, transform;
    max-width:700px;
}

.small{
    color:var(--text-secondary);
    letter-spacing:4px;
    margin-bottom:16px;
    font-size:17px;
    font-weight:600;
    transition:color var(--transition-speed) ease;
}

h1{
    font-size:50px;
    line-height:1.05;
    font-weight:700;
    color:var(--text-primary);
    transition:color var(--transition-speed) ease;
    margin-bottom:16px;
}

.description{
    margin-top:20px;
    max-width:550px;
    color:var(--text-secondary);
    font-size:20px;
    line-height:1.7;
    transition:color var(--transition-speed) ease;
}

/* ================= BUTTON ================= */

.buttons{
    display:flex;
    gap:24px;
    margin-top:40px;
    flex-wrap:wrap;
}

.buttons:has(:only-child){
    justify-content:center;
}

.hero-content .buttons{
    justify-content:center;
}

.btn{
    display:inline-flex;
    justify-content:center;
    align-items:center;
    padding:16px 38px;
    border-radius:35px;
    text-decoration:none;
    font-weight:600;
    border:1px solid var(--btn-border);
    background:var(--btn-bg);
    color:var(--text-primary);
    transition:.4s cubic-bezier(.4,0,.2,1), background var(--transition-speed) ease, border-color var(--transition-speed) ease, color var(--transition-speed) ease;
    font-size:15px;
}

.btn:hover{
    transform:translateY(-3px);
    box-shadow:0 8px 25px var(--btn-shadow);
    background:var(--btn-hover-bg);
    border-color:var(--btn-hover-border);
}

.outline{
    background:transparent;
    color:var(--text-primary);
    border-color:var(--btn-border);
}

.outline:hover{
    background:var(--btn-bg);
    color:var(--text-primary);
    border-color:var(--btn-hover-border);
}

/* ================= PHOTO ================= */

/* ================= SECTIONS ================= */

section{
    width:100%;
    max-width:1200px;
    margin:auto;
    padding:50px 30px;
    opacity:0;
    transform:translateY(30px);
    transition:.6s cubic-bezier(.4,0,.2,1);
}

section.show{
    opacity:1;
    transform:translateY(0);
}

#about,
#projects,
#contact{
    scroll-margin-top:90px;
}

h2{
    font-size:46px;
    margin-bottom:20px;
    position:relative;
    color:var(--text-primary);
    font-weight:700;
    transition:color var(--transition-speed) ease;
    display:inline-block;
}

h2::after{
    content:"";
    display:block;
    width:100%;
    height:3px;
    background:rgba(255,255,255,.3);
    border-radius:2px;
    margin-top:16px;
}

[data-theme="light"] h2::after{
    background:rgba(0,0,0,.2);
}

/* ================= ABOUT ================= */

.about-grid{
    display:flex;
    flex-direction:column;
    align-items:center;
    text-align:center;
    max-width:800px;
    margin:0 auto;
}

.about-text p{
    color:var(--text-secondary);
    margin-bottom:20px;
    max-width:650px;
    line-height:1.7;
    font-size:16px;
    transition:color var(--transition-speed) ease;
}

/* ================= PROJECTS ================= */

.cards{
    display:grid;
    grid-template-columns:repeat(auto-fit,minmax(300px,1fr));
    gap:35px;
}

.model-3d{
    border-radius:18px 18px 0 0;
}

.model-poster{
    position:relative;
    width:100%;
    height:100%;
    display:flex;
    align-items:center;
    justify-content:center;
    background:var(--bg-card);
}

.model-poster img{
    width:100%;
    height:100%;
    object-fit:cover;
    border-radius:18px 18px 0 0;
}

.project-photo-clickable{
    cursor:pointer;
    transition:transform 0.2s ease;
}

.project-photo-clickable:hover{
    transform:scale(1.02);
}

.loading-indicator{
    position:absolute;
    bottom:20px;
    left:50%;
    transform:translateX(-50%);
    background:rgba(0,0,0,0.7);
    color:white;
    padding:8px 16px;
    border-radius:20px;
    font-size:12px;
    font-weight:600;
    z-index:10;
    backdrop-filter:blur(10px);
}

[data-theme="light"] .loading-indicator{
    background:rgba(255,255,255,0.9);
    color:#1a1a1a;
}

.card{
    background:var(--bg-card);
    border-radius:18px;
    overflow:hidden;
    border:1px solid var(--border-color);
    transition:.4s cubic-bezier(.4,0,.2,1), background var(--transition-speed) ease, border-color var(--transition-speed) ease;
    opacity:0;
    transform:translateY(30px);
}

.card.show{
    opacity:1;
    transform:translateY(0);
}

.card:hover{
    transform:translateY(-8px);
    border-color:rgba(255,255,255,.15);
    box-shadow:
        0 20px 50px var(--card-hover-shadow),
        0 0 0 1px rgba(255,255,255,.02);
}

[data-theme="light"] .card:hover{
    border-color:rgba(0,0,0,.15);
    box-shadow:
        0 20px 50px var(--card-hover-shadow),
        0 0 0 1px rgba(0,0,0,.02);
}

.card-image{
    width:100%;
    aspect-ratio:16/10;
    overflow:hidden;
    background:var(--card-image-bg);
    transition:background var(--transition-speed) ease;
}

.card-image img{
    width:100%;
    height:100%;
    object-fit:cover;
    transition:.6s cubic-bezier(.4,0,.2,1);
}

.card:hover img{
    transform:scale(1.06);
}

.card h3{
    margin:24px 28px 14px;
    font-size:21px;
    color:var(--text-primary);
    font-weight:600;
    transition:color var(--transition-speed) ease;
}

.card p{
    margin:0 28px 28px;
    color:var(--text-secondary);
    line-height:1.6;
    font-size:15px;
    transition:color var(--transition-speed) ease;
}

/* ================= CONTACT ================= */

.contact{
    text-align:center;
}

.contact-text{
    color:var(--text-secondary);
    max-width:700px;
    margin:auto;
    margin-bottom:40px;
    line-height:1.7;
    font-size:16px;
    transition:color var(--transition-speed) ease;
}

.contact-links{
    display:flex;
    justify-content:center;
    flex-wrap:wrap;
    gap:35px;
    margin-bottom:45px;
}

.contact-links a{
    color:var(--text-primary);
    text-decoration:none;
    transition:.3s ease;
    font-size:16px;
    position:relative;
}

.contact-links a:hover{
    color:var(--text-secondary);
}

/* ================= FOOTER ================= */

footer{
    background:var(--footer-bg);
    text-align:center;
    color:var(--text-secondary);
    padding:60px 30px;
    transition:background var(--transition-speed) ease;
}

.footer-content{
    max-width:1200px;
    margin:auto;
}

.footer-name{
    font-size:24px;
    font-weight:700;
    color:var(--text-primary);
    margin-bottom:8px;
    letter-spacing:2px;
    transition:color var(--transition-speed) ease;
}

.footer-title{
    font-size:15px;
    color:var(--text-secondary);
    margin-bottom:30px;
    font-weight:500;
    transition:color var(--transition-speed) ease;
}

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

.footer-links a{
    color:var(--text-secondary);
    text-decoration:none;
    transition:.3s ease;
    font-size:15px;
}

.footer-links a:hover{
    color:var(--text-primary);
}

.footer-bottom{
    margin-top:40px;
    padding-top:30px;
    border-top:1px solid rgba(255,255,255,.06);
    font-size:14px;
    color:#888;
}

[data-theme="light"] .footer-bottom{
    border-top:1px solid rgba(0,0,0,.06);
    color:#666;
}

.footer-bottom p{
    margin-bottom:8px;
}

/* ================= ANIMATION ================= */

@keyframes fade{

    from{
        opacity:0;
        transform:translateY(25px);
    }

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

}

/* ================= SCROLL TRANSITION ================= */

/* ================= TABLET ================= */

@media(max-width:900px){

    .hero-content{
        align-items:center;
        text-align:center;
    }

    .about-grid{
        text-align:center;
    }

    h2::after{
        margin:auto;
        margin-top:16px;
    }

    .description{
        margin-left:auto;
        margin-right:auto;
    }

    .buttons{
        justify-content:center;
    }

    .buttons.single-btn{
        justify-content:center;
    }

    h1{
        font-size:52px;
    }

    .small{
        font-size:14px;
    }

    .footer-links{
        gap:25px;
    }

    .logo{
        gap:10px;
    }

    .nav-profile-photo{
        width:32px;
        height:32px;
    }

}

/* ================= MOBILE ================= */

@media(max-width:600px){

    nav{
        height:75px;
        padding:0 20px;
    }

    .logo{
        font-size:14px;
        letter-spacing:1.5px;
        gap:8px;
    }

    nav ul li:not(:last-child):not(:nth-last-child(2)){
        display:none;
    }

    .nav-profile-photo{
        width:28px;
        height:28px;
    }

    .theme-toggle{
        margin-left:10px;
    }

    .hero-content{
        align-items:center;
        text-align:center;
    }

    .small{
        font-size:13px;
    }

    h1{
        font-size:34px;
    }

    h2{
        font-size:32px;
    }

    .description{
        font-size:16px;
    }

    .cards{
        grid-template-columns:1fr;
    }

    .buttons{
        flex-direction:column;
        align-items:center;
    }

    .btn{
        width:100%;
    }

    .footer-name{
        font-size:20px;
    }

    .footer-links{
        flex-direction:column;
        gap:20px;
    }

    .theme-toggle{
        padding:6px 12px;
    }

    .theme-toggle svg{
        width:18px;
        height:18px;
    }

    .nav-cv{
        padding:8px 16px;
        font-size:14px;
    }

}