:root {
    --bg-deep: #050a12;
    --bg-mid: #0b1626;
    --card-base: #2e2e30;
    --card-mid: #363638;
    --card-light: #3e3e40;
    --card-highlight: rgba(255, 255, 255, 0.07);
    --card-edge: rgba(255, 255, 255, 0.09);
    --text-primary: #f5f7fa;
    --text-secondary: #a8b4c4;
    --text-muted: #6b7b8f;
    --accent: #7aa2f7;

    --font-display: "SF Pro Display", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-body: "SF Pro Text", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-mono: "SF Mono", "JetBrains Mono", "Fira Code", monospace;
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
html { scroll-behavior: auto; }

body {
    font-family: var(--font-body);
    background: var(--bg-deep);
    color: var(--text-primary);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
}

.site {
    min-height: 100vh;
    padding-top: 64px;
    background:
        radial-gradient(ellipse at 25% 15%, rgba(20, 40, 72, 0.55) 0%, transparent 50%),
        radial-gradient(ellipse at 75% 85%, rgba(8, 18, 36, 0.85) 0%, transparent 50%),
        var(--bg-deep);
}

/* ===== Top navigation ===== */
.top-nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    gap: 1.5rem;
    height: 64px;
    padding: 0 4vw;
    background: rgba(46, 46, 48, 0.55);
    backdrop-filter: blur(24px) saturate(180%);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    border-bottom: 1px solid rgba(255, 255, 255, 0.12);
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.15);
}

.menu-btn {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 32px;
    height: 32px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
}

.menu-btn span {
    display: block;
    width: 100%;
    height: 2px;
    background: var(--text-primary);
    border-radius: 1px;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.lang-btn {
    margin-left: auto;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--text-secondary);
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 999px;
    padding: 0.4rem 0.9rem;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.lang-btn:hover,
.lang-btn:focus {
    background: rgba(255, 255, 255, 0.14);
    color: var(--text-primary);
    border-color: rgba(255, 255, 255, 0.22);
}

.top-nav__links {
    display: flex;
    align-items: center;
    gap: clamp(0.75rem, 2vw, 1.5rem);
    margin-left: auto;
}

.top-nav__link {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--text-secondary);
    padding: 0.35rem 0.1rem;
    transition: color 0.2s ease;
}

.top-nav__link:hover,
.top-nav__link:focus {
    color: var(--text-primary);
}

/* ===== Side panel (page-turn from left) ===== */
.side-panel__perspective {
    position: fixed;
    top: 64px;
    left: 0;
    z-index: 90;
    width: min(320px, 80vw);
    height: calc(100vh - 64px);
    perspective: 1000px;
    pointer-events: none;
}

.side-panel {
    width: 100%;
    height: 100%;
    padding: 2rem 1.5rem;
    background: var(--card-base);
    border-right: 1px solid var(--card-edge);
    box-shadow: 12px 0 40px rgba(0, 0, 0, 0.35);
    transform-origin: left center;
    transform: rotateY(-90deg);
    opacity: 0;
    pointer-events: none;
    will-change: transform, opacity;
}

.side-panel__nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.side-panel__link {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--text-secondary);
    padding: 0.85rem 1rem;
    border-radius: 12px;
    transition: background 0.2s ease, color 0.2s ease;
}

.side-panel__link:hover,
.side-panel__link:focus {
    background: var(--card-mid);
    color: var(--text-primary);
}

.side-panel__link--contact {
    margin-top: auto;
    color: var(--accent);
    border: 1px solid rgba(122, 162, 247, 0.35);
    text-align: center;
}

.side-panel__link--contact:hover,
.side-panel__link--contact:focus {
    background: rgba(122, 162, 247, 0.1);
    border-color: rgba(122, 162, 247, 0.6);
}

/* ===== Deck ===== */
.deck-section {
    position: relative;
    width: 100%;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-top: 64px;
    perspective: 1400px;
    overflow: hidden;
    background: var(--bg-deep);
}

.deck-stage {
    position: relative;
    width: min(860px, 92vw);
    aspect-ratio: 16 / 10;
    transform-style: preserve-3d;
}

.card-stack {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
}

.card {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: 24px;
    overflow: hidden;
    background: linear-gradient(145deg, var(--card-light) 0%, var(--card-mid) 45%, var(--card-base) 100%);
    border: 1px solid var(--card-edge);
    will-change: transform, opacity;
}

/* Фиксируем z-index по DOM-порядку: первая карточка в HTML — сверху.
   JS меняет transform/opacity, но z-index держится через CSS-классы шагов. */
.card[data-card="0"] { z-index: 50; }
.card[data-card="1"] { z-index: 40; }
.card[data-card="2"] { z-index: 30; }
.card[data-card="3"] { z-index: 20; }
.card[data-card="4"] { z-index: 10; }

/* Глубина в стопке: 0 — верх, N-1 — низ. */
.card--depth-0 { z-index: 50 !important; }
.card--depth-1 { z-index: 40 !important; }
.card--depth-2 { z-index: 30 !important; }
.card--depth-3 { z-index: 20 !important; }
.card--depth-4 { z-index: 10 !important; }


.card__shine {
    position: absolute;
    inset: 0;
    pointer-events: none;
    background:
        radial-gradient(ellipse at 12% 6%, var(--card-highlight) 0%, transparent 38%),
        linear-gradient(155deg, rgba(255, 255, 255, 0.05) 0%, transparent 32%);
    border-radius: inherit;
    z-index: 2;
}

.card::after {
    content: "";
    position: absolute;
    inset: 0;
    border-radius: inherit;
    box-shadow: inset 0 -16px 36px rgba(0, 0, 0, 0.18);
    pointer-events: none;
    z-index: 3;
}

.card__content {
    position: relative;
    z-index: 4;
    height: 100%;
    padding: 8% 9%;
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
}

.card__eyebrow {
    font-family: var(--font-mono);
    font-size: clamp(0.62rem, 1.1vw, 0.75rem);
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 1rem;
}

.card__title {
    font-family: var(--font-display);
    font-size: clamp(1.8rem, 4.2vw, 2.8rem);
    font-weight: 700;
    line-height: 1.08;
    letter-spacing: -0.03em;
    margin: 0 0 0.8rem;
    color: var(--text-primary);
}

.card__description {
    font-size: clamp(0.9rem, 1.8vw, 1.05rem);
    line-height: 1.55;
    color: var(--text-secondary);
    max-width: 44ch;
    margin: 0 0 1.6rem;
}

.card__action {
    align-self: flex-start;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.09em;
    text-transform: uppercase;
    color: var(--accent);
    padding: 0.65rem 1.25rem;
    border: 1px solid rgba(122, 162, 247, 0.35);
    border-radius: 999px;
    transition: background 0.2s ease, border-color 0.2s ease;
}

.card__action:hover {
    background: rgba(122, 162, 247, 0.1);
    border-color: rgba(122, 162, 247, 0.6);
}

/* ===== Scroll hint ===== */
.scroll-hint {
    position: absolute;
    bottom: -56px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.4rem;
    color: var(--text-muted);
    font-family: var(--font-mono);
    font-size: 0.65rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    opacity: 0.7;
}

.scroll-hint__line {
    width: 1px;
    height: 28px;
    background: linear-gradient(to bottom, var(--text-muted), transparent);
}

/* ===== Content section — Space Gray, не тёмно-синий ===== */
.content-section,
.contact-section {
    min-height: 60vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 1.5rem;
    background:
        linear-gradient(to bottom, var(--bg-deep) 0%, transparent 18%),
        var(--card-base);
}

.content-section__inner,
.contact-section__inner {
    max-width: 680px;
    text-align: center;
}

.content-section__label,
.contact-section__label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent);
    display: block;
    margin-bottom: 1rem;
}

.content-section__title,
.contact-section__title {
    font-family: var(--font-display);
    font-size: clamp(1.6rem, 4vw, 2.6rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 1rem;
}

.content-section__text,
.contact-section__text {
    font-size: clamp(1rem, 2.2vw, 1.15rem);
    line-height: 1.6;
    color: var(--text-secondary);
}

/* ===== Projects section ===== */
.projects-section {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 6rem 1.5rem;
    overflow: hidden;
}

.projects-section__bg {
    position: absolute;
    inset: 0;
    background: var(--bg-deep);
    transition: background 0.6s ease;
    z-index: 0;
}

.projects-section__bg::after {
    content: "";
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 20% 20%, rgba(255, 255, 255, 0.04) 0%, transparent 45%),
        radial-gradient(ellipse at 80% 80%, rgba(0, 0, 0, 0.25) 0%, transparent 45%);
    pointer-events: none;
    z-index: 0;
}

/* Плавный переход от визиток (deck) к проектам: сверху фон deck-section. */
.projects-section__bg::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 180px;
    background: linear-gradient(to bottom, var(--bg-deep) 0%, transparent 100%);
    pointer-events: none;
    z-index: 1;
}

.projects-section__inner {
    position: relative;
    z-index: 1;
    width: min(1100px, 96vw);
    text-align: center;
}

.projects-section__label {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    color: var(--accent);
    display: block;
    margin-bottom: 0.6rem;
}

.projects-section__title {
    font-family: var(--font-display);
    font-size: clamp(1.6rem, 4vw, 2.4rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin: 0 0 2.5rem;
    transition: opacity 0.35s ease, transform 0.35s ease;
}

.projects-carousel {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 460px;
    perspective: 1400px;
}

.projects-track {
    position: relative;
    width: min(560px, 86vw);
    height: 380px;
    transform-style: preserve-3d;
}

.carousel-arrow {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    z-index: 5;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.08);
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: 50%;
    color: var(--text-primary);
    cursor: pointer;
    transition: background 0.2s ease, border-color 0.2s ease;
}

.carousel-arrow:hover {
    background: rgba(255, 255, 255, 0.14);
    border-color: rgba(255, 255, 255, 0.24);
}

.carousel-arrow svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.carousel-arrow--prev { left: clamp(-60px, -5vw, -20px); }
.carousel-arrow--next { right: clamp(-60px, -5vw, -20px); }

.project-card {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    perspective: 1200px;
    transition: transform 0.55s cubic-bezier(0.22, 1, 0.36, 1), opacity 0.55s ease;
    will-change: transform, opacity;
}

.project-card[data-pos="prev"] {
    transform: translateX(-70%) scale(0.78) rotateY(18deg);
    opacity: 0.45;
    z-index: 1;
}

.project-card[data-pos="active"] {
    transform: translateX(0) scale(1) rotateY(0deg);
    opacity: 1;
    z-index: 3;
}

.project-card[data-pos="next"] {
    transform: translateX(70%) scale(0.78) rotateY(-18deg);
    opacity: 0.45;
    z-index: 1;
}

.project-card[data-pos="hidden"] {
    opacity: 0;
    pointer-events: none;
    z-index: 0;
    transform: translateX(0) scale(0.7);
}

.project-card__inner {
    position: relative;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    transition: transform 0.65s cubic-bezier(0.22, 1, 0.36, 1);
    border-radius: 28px;
}

.project-card.is-flipped .project-card__inner {
    transform: rotateY(180deg);
}

.project-card__front,
.project-card__back {
    position: absolute;
    inset: 0;
    border-radius: 28px;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    overflow: hidden;
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
}

.project-card__front {
    display: flex;
    flex-direction: column;
    justify-content: flex-end;
    padding: 2rem;
    background: linear-gradient(145deg, rgba(255,255,255,0.12) 0%, rgba(0,0,0,0.08) 100%);
}

.project-card__corner {
    position: absolute;
    top: 0;
    right: 0;
    width: 64px;
    height: 64px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    z-index: 5;
}

.project-card__corner::before {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    width: 64px;
    height: 64px;
    background: linear-gradient(225deg, rgba(255,255,255,0.35) 0%, rgba(255,255,255,0.08) 45%, transparent 65%);
    border-radius: 0 0 0 100%;
    box-shadow: inset 2px -2px 6px rgba(0, 0, 0, 0.08);
    transition: background 0.2s ease;
}

.project-card__corner:hover::before {
    background: linear-gradient(225deg, rgba(255,255,255,0.5) 0%, rgba(255,255,255,0.14) 45%, transparent 65%);
}

.project-card__hint {
    position: absolute;
    top: 10px;
    right: 10px;
    width: 22px;
    height: 22px;
    background: rgba(74, 222, 128, 0.65);
    border-radius: 50%;
    box-shadow: 0 0 0 0 rgba(74, 222, 128, 0.5);
    animation: hintPulse 1.8s ease-out infinite;
    pointer-events: none;
}

.project-card__hint.is-hidden {
    display: none;
}

@keyframes hintPulse {
    0% { box-shadow: 0 0 0 0 rgba(74, 222, 128, 0.5); }
    70% { box-shadow: 0 0 0 12px rgba(74, 222, 128, 0); }
    100% { box-shadow: 0 0 0 0 rgba(74, 222, 128, 0); }
}

.project-card__name {
    font-family: var(--font-display);
    font-size: clamp(1.6rem, 4vw, 2.4rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: #fff;
    text-shadow: 0 2px 12px rgba(0, 0, 0, 0.25);
    text-align: left;
}

.project-card__back {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 2rem;
    background: #e8e8ea;
    color: #111;
    transform: rotateY(180deg);
    text-align: left;
}

.project-card__close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    line-height: 1;
    color: #555;
    background: rgba(0, 0, 0, 0.06);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    transition: background 0.2s ease, color 0.2s ease;
}

.project-card__close:hover {
    background: rgba(0, 0, 0, 0.12);
    color: #000;
}

.project-card__back-title {
    font-family: var(--font-display);
    font-size: clamp(1.3rem, 3vw, 1.8rem);
    font-weight: 700;
    margin: 0 0 1rem;
    color: #111;
}

.project-card__back-desc {
    font-size: clamp(0.9rem, 1.8vw, 1rem);
    line-height: 1.55;
    color: #333;
    margin: 0 0 1.5rem;
    flex: 1 1 auto;
}

.project-card__actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    width: 100%;
}

.project-card__btn {
    flex: 1 1 auto;
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    text-align: center;
    padding: 0.75rem 1rem;
    border-radius: 999px;
    cursor: pointer;
    transition: transform 0.15s ease, opacity 0.2s ease;
    border: none;
}

.project-card__btn:hover {
    transform: translateY(-1px);
    opacity: 0.9;
}

.project-card__btn--demo {
    background: #111;
    color: #fff;
}

.project-card__btn--order {
    background: transparent;
    color: #111;
    border: 1px solid rgba(0, 0, 0, 0.35);
}

.carousel-dots {
    display: flex;
    justify-content: center;
    gap: 0.6rem;
    margin-top: 1.5rem;
}

.carousel-dot {
    width: 8px;
    height: 8px;
    padding: 0;
    background: rgba(255, 255, 255, 0.25);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    transition: background 0.3s ease, transform 0.3s ease;
}

.carousel-dot.is-active {
    background: rgba(255, 255, 255, 0.85);
    transform: scale(1.3);
}

/* ===== Lead form ===== */
.contact-section {
    background:
        linear-gradient(to bottom, var(--bg-deep) 0%, transparent 18%),
        var(--card-base);
}

.lead-form {
    width: min(560px, 100%);
    margin: 2rem auto 0;
    text-align: left;
}

.lead-form__honeypot {
    position: absolute;
    left: -9999px;
    opacity: 0;
    pointer-events: none;
}

.lead-form__field {
    margin-bottom: 1.1rem;
}

.lead-form__row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.lead-form label {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.65rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 0.4rem;
}

.lead-form input,
.lead-form select,
.lead-form textarea {
    width: 100%;
    padding: 0.85rem 1rem;
    background: rgba(0, 0, 0, 0.22);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    color: var(--text-primary);
    font-family: var(--font-body);
    font-size: 0.95rem;
    outline: none;
    transition: border-color 0.2s ease, background 0.2s ease;
}

.lead-form input:focus,
.lead-form select:focus,
.lead-form textarea:focus {
    border-color: var(--accent);
    background: rgba(0, 0, 0, 0.3);
}

.lead-form input::placeholder,
.lead-form textarea::placeholder {
    color: var(--text-muted);
    opacity: 0.7;
}

.lead-form select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%23a8b4c4' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem center;
}

.lead-form select option {
    background: var(--card-base);
    color: var(--text-primary);
}

.lead-form__submit {
    width: 100%;
    margin-top: 0.5rem;
    padding: 1rem;
    font-family: var(--font-mono);
    font-size: 0.72rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: #fff;
    background: var(--accent);
    border: none;
    border-radius: 999px;
    cursor: pointer;
    transition: background 0.2s ease, transform 0.15s ease;
}

.lead-form__submit:hover {
    background: #5d8ce0;
    transform: translateY(-1px);
}

.lead-form__status {
    min-height: 1.4rem;
    margin-top: 0.75rem;
    text-align: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

.lead-form__status.is-error {
    color: #ff8a8a;
}

.lead-form__status.is-success {
    color: #8affa8;
}

/* ===== Reduced motion / mobile ===== */
@media (prefers-reduced-motion: reduce) {
    .card { transition: none !important; }
    .scroll-hint { display: none; }
}

@media (max-width: 640px) {
    .top-nav {
        gap: 0.75rem;
        padding: 0 1rem;
    }
    .top-nav__links {
        gap: 0.5rem;
    }
    .top-nav__link {
        font-size: 0.65rem;
        letter-spacing: 0.05em;
    }
    .lang-btn {
        padding: 0.35rem 0.65rem;
        font-size: 0.65rem;
    }
    .side-panel__perspective {
        width: min(280px, 80vw);
    }
    .projects-carousel {
        height: 400px;
    }
    .projects-track {
        height: 320px;
    }
    .carousel-arrow--prev { left: -10px; }
    .carousel-arrow--next { right: -10px; }
    .project-card[data-pos="prev"] {
        transform: translateX(-55%) scale(0.72) rotateY(14deg);
        opacity: 0.35;
    }
    .project-card[data-pos="next"] {
        transform: translateX(55%) scale(0.72) rotateY(-14deg);
        opacity: 0.35;
    }
    .lead-form__row {
        grid-template-columns: 1fr;
    }
    .deck-stage {
        width: 92vw;
        aspect-ratio: 3 / 2;
    }
    .card { border-radius: 18px; }
    .card__content { padding: 7% 8%; }
}