body {
    margin: 0;
    font-family: 'Poppins', sans-serif;
    background: #ffffff;
    color: #000000;
    overflow-x: hidden;
    position: relative;
}

/* ===========================
   MOBILE HEADER (всегда закреплен сверху)
   =========================== */

.mobile-header {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 60px;
    background: #ffffff;
    border-bottom: 1px solid #f0f0f0;
    z-index: 50;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
}

.mobile-burger {
    cursor: pointer;
    font-size: 1.6em;
    color: #000;
    transition: transform 0.4s ease, color 0.3s ease;
}

.mobile-burger.active {
    transform: rotate(90deg);
    color: #555;
}

.mobile-title {
    margin: 0;
    font-size: 1.2rem;
    font-weight: 600;
    color: #000;
}

header {
    position: fixed;
    top: 20px;
    right: 100px;
    z-index: 30;
}

.burger-menu {
    cursor: pointer;
    font-size: 2.2em;
    color: #000;
    transition: transform 0.4s ease, color 0.3s ease;
    z-index: 31;
}

.burger-menu:hover { color: #555; }
.burger-menu.active { transform: rotate(90deg); color: #555; }

.social-sidebar {
    position: fixed;
    bottom: 30px;
    left: 30px;
    display: flex;
    flex-direction: column;
    gap: 22px;
    z-index: 20;
}

.social-sidebar a {
    color: #000;
    font-size: 1.6em;
    transition: transform 0.3s ease;
}

.social-sidebar a:hover { transform: scale(1.25); }

/* Меню */

.nav-menu {
    position: fixed;
    top: -100vh;
    left: 0;
    width: 100%;
    height: 100vh;
    background: #000000;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 22px;
    transition: top 0.6s cubic-bezier(0.7, 0, 0.3, 1);
    z-index: 100;
    opacity: 0;
    visibility: hidden;
}

.nav-menu.active {
    top: 0;
    opacity: 1;
    visibility: visible;
}

.nav-menu a {
    color: #fff;
    font-size: 2.8em;
    text-decoration: none;
    transition: transform 0.3s ease;
}

.nav-menu a:hover {
    transform: scale(1.08);
}

/* Skills Section */

.skills-main {
    min-height: 99vh;
    padding: 10px 10px 0px;
    position: relative;
}

.skills-main h1 {
    font-size: 4rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 30px;
    letter-spacing: -2px;
    opacity: 0;
    transform: translateY(-50px);
    animation: titleFadeIn 1.2s ease-out forwards;
}

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

.skills-grid {
    display: grid;
    grid-template-columns: repeat(4, 260px);
    justify-content: center;
    gap: 80px;
    max-width: 100%;
    margin: 0 auto;
    transform: none;
}

/* КАРТОЧКИ */
.skill-card {
    perspective: 1200px;
    width: 260px;
    height: 260px;
    position: relative;
    opacity: 0;
    transform: translateY(60px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

/* Внутренний контейнер вращается */
.skill-card-inner {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    cursor: pointer;
    transition: transform 0.6s cubic-bezier(.22,1,.36,1);

    /* фиксация центра, чтобы flip не сдвигал карточку */
    transform-origin: center center;
}

/* Переворот по клику */
.skill-card.is-flipped .skill-card-inner {
    transform: rotateY(180deg);
}

/* Передняя и задняя стороны */
.skill-front,
.skill-back {
    position: absolute;
    width: 100%;
    height: 100%;
    border-radius: 20px;
    overflow: hidden;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;

    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 30px;
    text-align: center;

    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    transition: transform 0.35s cubic-bezier(.22,1,.36,1),
                box-shadow 0.35s ease;
}

.skill-front {
    background: linear-gradient(135deg,#f8f9fa,#e9ecef);
}

.skill-back {
    background: linear-gradient(135deg,#212529,#343a40);
    color: white;
    transform: rotateY(180deg);
}

/* Иконка */
.skill-front i {
    font-size: 5rem;
    margin-bottom: 20px;
    color: #6c757d;
    transition: transform 0.35s cubic-bezier(.22,1,.36,1);
}

/* Заголовок */
.skill-front h3 {
    font-size: 1.5rem;
    margin: 0 0 15px;
    transition: transform 0.35s cubic-bezier(.22,1,.36,1);
}

/* Текст */
.skill-front p,
.skill-back p {
    font-size: 1.05rem;
    margin: 6px 0;
    opacity: 0.9;
}

/* Hover-анимация */
.skill-card:hover .skill-front {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px rgba(0,0,0,0.12),
                0 0 25px rgba(0,0,0,0.05);
}

.skill-card:hover .skill-front i {
    transform: translateY(-10px) scale(1.1);
}

.skill-card:hover .skill-front h3 {
    transform: translateY(-6px);
}

/* Смещение рядов (как у тебя было) */
.skills-grid .skill-card:nth-child(-n+4){
    transform: translateY(0);
}

.skills-grid .skill-card:nth-child(n+5){
    transform: translateY(0);
}

/* Вертикальная полоска */

.vertical-indicator {
    position: absolute;
    right: 0px;
    top: 480px;
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 8px;
    transform: rotate(90deg);
    font-size: 1.15rem;
    font-weight: 700;
    color: #222;
    letter-spacing: 2px;
}

.vertical-indicator hr.short {
    width: 20px;
    height: 1px;
    background: #222;
    border: none;
    margin: 0;
}

.vertical-indicator hr.long {
    width: 40px;
    height: 1px;
    background: #222;
    border: none;
    margin: 0;
}

footer {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 0.85rem;
    color: #555;
}

/* смещение верхнего ряда */

/* смещение рядов */

.skills-grid .skill-card:nth-child(-n+4){
    transform: translateX(50px);
}

.skills-grid .skill-card:nth-child(n+5){
    transform: translateX(-50px);
}

/* появление карточек */

.skill-card {
    opacity: 0;
    transform: translateY(60px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

.max-icon{
width:24px;
height:24px;
object-fit:contain;
filter: grayscale(100%);
transition: .3s;
}

.social-sidebar a:hover .max-icon{
filter: grayscale(0%);
transform: scale(1.2);
}

/* ===========================
   TABLET RESPONSIVE (768px and below)
   =========================== */

@media (max-width: 768px) {
    /* Показываем мобильную панель */
    .mobile-header {
        display: flex;
    }

    /* Скрываем социальную панель на мобильных */
    .social-sidebar {
        display: none;
    }

    header {
        right: 20px;
        top: 15px;
    }

    .burger-menu {
        font-size: 1.8em;
    }

    .nav-menu a {
        font-size: 2.2em;
    }

    .skills-main {
        padding: 80px 20px 40px;
        max-width: 100%;
        overflow-x: hidden;
    }

    .skills-main h1 {
        font-size: 2.5rem;
        margin-bottom: 40px;
    }

    .skills-grid {
        grid-template-columns: repeat(2, 200px);
        gap: 60px;
        transform: none;
        justify-content: center;
    }

    .skill-card {
        width: 200px;
        height: 200px;
    }

    .skill-card:nth-child(-n+4) {
        transform: translateX(0);
    }

    .skill-card:nth-child(n+5) {
        transform: translateX(0);
    }

    .skill-front i {
        font-size: 3.2rem;
        margin-bottom: 12px;
    }

    .skill-front h3 {
        font-size: 1.05rem;
    }

    .skill-front p,
    .skill-back p {
        font-size: 0.85rem;
    }

    .vertical-indicator {
        display: none;
    }

    footer {
        position: relative;
        bottom: auto;
        transform: none;
    }
}

/* SMALL MOBILE (480px and below) */
@media (max-width: 480px) {
    
    .skills-main h1 {
    display: none;
}

    .mobile-header {
        padding: 0 15px;
        height: 55px;
    }

    header {
        right: 15px;
        top: 12px;
    }

    .burger-menu {
        font-size: 1.5em;
    }

    .nav-menu a {
        font-size: 1.8em;
    }

    /* MAIN */
    .skills-main {
        padding: 80px 0px 140px; /* запас под фиксированный футер */
        min-height: auto;
        overflow-x: hidden;
    }

    .skills-main h1 {
        font-size: 1.6rem;
        margin-bottom: 25px;
        margin-top: 10px;
    }

    /* GRID */
    .skills-grid {
        display: grid;
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
        justify-items: stretch; /* важно для растяжения */
        transform: none;
        max-width: 360px;   /* 🔥 ограничиваем ширину сетки */
        margin: 0 auto;
    }

    /* CARD */
    .skill-card {
    width: 100%;
    max-width: 190px; /* ← вот здесь регулируешь размер */
    aspect-ratio: 1 / 1;

    perspective: 1000px;
}

    /* УБИРАЕМ ВСЕ СДВИГИ */
    .skill-card:nth-child(-n+4),
    .skill-card:nth-child(n+5) {
        transform: none !important;
    }

    /* INNER (FLIP BASE) */
    .skill-card-inner {
        width: 100%;
        height: 100%;
        position: relative;

        transform-style: preserve-3d;
        transform-origin: center;
    }

    .skill-card.flipped .skill-card-inner {
        transform: rotateY(180deg);
    }

    /* FRONT / BACK */
    .skill-front,
    .skill-back {
        position: absolute;
        inset: 0;

        backface-visibility: hidden;
        -webkit-backface-visibility: hidden;

        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;

        padding: 12px;
        box-sizing: border-box;
    }

    .skill-back {
        transform: rotateY(180deg);
    }

    /* CONTENT */
    .skill-front i {
        font-size: 2.2rem;
        margin-bottom: 8px;
    }

    .skill-front h3 {
        font-size: 0.95rem;
        text-align: center;
    }

    .skill-front p,
    .skill-back p {
        font-size: 0.8rem;
        text-align: center;
    }

    .max-icon {
        width: 18px;
        height: 18px;
    }

    /* FOOTER */
    footer {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;

        padding: 10px 10px 5px;
        font-size: 0.65rem;
        background: #ffffff;
        z-index: 10;
        text-align: center;
    }
}