.r3d-flipbook-wrap {
    --r3d-radius: 24px;
    width: min(100%, var(--r3d-max-width));
    margin: 28px auto;
    color: #fff;
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

.r3d-flipbook-error {
    border: 1px solid #fecaca;
    color: #991b1b;
    background: #fef2f2;
    border-radius: 12px;
    padding: 14px 16px;
    font-family: inherit;
}

.r3d-viewer {
    position: relative;
    border-radius: calc(var(--r3d-radius) + 8px);
    background:
        radial-gradient(circle at top left, color-mix(in srgb, var(--r3d-primary) 42%, transparent), transparent 36%),
        linear-gradient(145deg, color-mix(in srgb, var(--r3d-bg) 86%, #ffffff 14%), var(--r3d-bg));
    padding: 18px;
    overflow: hidden;
    box-shadow: 0 28px 90px rgba(0, 0, 0, 0.36);
}

.r3d-viewer::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background: linear-gradient(120deg, rgba(255,255,255,.16), transparent 28%, transparent 70%, rgba(255,255,255,.09));
    opacity: .85;
}

.r3d-header {
    position: relative;
    z-index: 2;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 14px;
}

.r3d-title-group {
    min-width: 0;
}

.r3d-title {
    margin: 0;
    color: #fff;
    font-size: clamp(18px, 2vw, 28px);
    line-height: 1.12;
    letter-spacing: -0.03em;
}

.r3d-subtitle {
    margin: 6px 0 0;
    color: rgba(255,255,255,.74);
    font-size: 14px;
    line-height: 1.5;
}

.r3d-toolbar {
    position: relative;
    z-index: 4;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 8px;
    padding: 10px;
    border: 1px solid rgba(255,255,255,.14);
    border-radius: 999px;
    background: rgba(255,255,255,.11);
    backdrop-filter: blur(14px);
}

.r3d-toolbar.r3d-toolbar-bottom {
    margin-top: 16px;
}

.r3d-toolbar.r3d-toolbar-top {
    margin-bottom: 16px;
}

.r3d-btn {
    min-width: 40px;
    min-height: 40px;
    border: 1px solid rgba(255,255,255,.18);
    border-radius: 999px;
    padding: 0 13px;
    background: rgba(255,255,255,.12);
    color: #fff;
    font: inherit;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: transform .2s ease, background .2s ease, opacity .2s ease;
}

.r3d-btn:hover:not(:disabled) {
    transform: translateY(-1px);
    background: var(--r3d-primary);
}

.r3d-btn:disabled {
    opacity: .38;
    cursor: not-allowed;
}

.r3d-page-status {
    min-height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0 14px;
    border-radius: 999px;
    background: rgba(255,255,255,.92);
    color: #0f172a;
    font-size: 13px;
    font-weight: 800;
}

.r3d-stage-wrap {
    position: relative;
    z-index: 3;
    perspective: 2400px;
    overflow: visible;
}

.r3d-book-stage {
    position: relative;
    height: var(--r3d-height-desktop);
    max-height: 78vh;
    display: grid;
    place-items: center;
    transform-style: preserve-3d;
    transition: transform .25s ease;
}

.r3d-book {
    position: relative;
    width: 100%;
    height: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    transform-style: preserve-3d;
    filter: drop-shadow(0 30px 46px rgba(0,0,0,.34));
}

.r3d-book::before {
    content: "";
    position: absolute;
    top: 2%;
    bottom: 2%;
    left: 50%;
    width: 28px;
    z-index: 20;
    transform: translateX(-50%);
    background: linear-gradient(90deg, transparent, rgba(0,0,0,.28), rgba(255,255,255,.10), rgba(0,0,0,.18), transparent);
    pointer-events: none;
    border-radius: 999px;
}

.r3d-page-slot {
    position: relative;
    min-width: 0;
    height: 100%;
    background: var(--r3d-paper);
    overflow: hidden;
    transform-style: preserve-3d;
    backface-visibility: hidden;
}

.r3d-page-left {
    border-radius: var(--r3d-radius) 0 0 var(--r3d-radius);
    box-shadow: inset -18px 0 34px rgba(0,0,0,.12), inset 0 0 0 1px rgba(0,0,0,.05);
}

.r3d-page-right {
    border-radius: 0 var(--r3d-radius) var(--r3d-radius) 0;
    box-shadow: inset 18px 0 34px rgba(0,0,0,.10), inset 0 0 0 1px rgba(0,0,0,.05);
}

.r3d-page-slot canvas {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    background: var(--r3d-paper);
}

.r3d-page-placeholder {
    height: 100%;
    display: grid;
    place-items: center;
    color: #475569;
    background: linear-gradient(135deg, var(--r3d-paper), color-mix(in srgb, var(--r3d-paper) 82%, #000 18%));
}

.r3d-flipper {
    position: absolute;
    top: 0;
    bottom: 0;
    left: 50%;
    width: 50%;
    z-index: 30;
    transform-style: preserve-3d;
    transform-origin: left center;
    pointer-events: none;
    display: none;
}

.r3d-flipper.is-active {
    display: block;
    animation: r3dFlipForward .78s cubic-bezier(.2, .72, .2, 1) forwards;
}

.r3d-flipper.is-backward {
    left: 0;
    transform-origin: right center;
    animation: r3dFlipBackward .78s cubic-bezier(.2, .72, .2, 1) forwards;
}

.r3d-flipper-face {
    position: absolute;
    inset: 0;
    background: var(--r3d-paper);
    overflow: hidden;
    backface-visibility: hidden;
    box-shadow: 0 18px 42px rgba(0,0,0,.3);
}

.r3d-flipper-front {
    border-radius: 0 var(--r3d-radius) var(--r3d-radius) 0;
}

.r3d-flipper-back {
    transform: rotateY(180deg);
    border-radius: var(--r3d-radius) 0 0 var(--r3d-radius);
}

.r3d-flipper.is-backward .r3d-flipper-front {
    border-radius: var(--r3d-radius) 0 0 var(--r3d-radius);
}

.r3d-flipper.is-backward .r3d-flipper-back {
    border-radius: 0 var(--r3d-radius) var(--r3d-radius) 0;
}

.r3d-flipper canvas {
    width: 100%;
    height: 100%;
    object-fit: contain;
    display: block;
    background: var(--r3d-paper);
}

.r3d-flipper::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(90deg, rgba(0,0,0,.28), transparent 34%, rgba(255,255,255,.2) 64%, rgba(0,0,0,.18));
    mix-blend-mode: multiply;
    opacity: .62;
    pointer-events: none;
    border-radius: inherit;
}

@keyframes r3dFlipForward {
    0% { transform: rotateY(0deg); }
    48% { transform: rotateY(-92deg) translateZ(18px); }
    100% { transform: rotateY(-180deg); }
}

@keyframes r3dFlipBackward {
    0% { transform: rotateY(0deg); }
    48% { transform: rotateY(92deg) translateZ(18px); }
    100% { transform: rotateY(180deg); }
}

.r3d-edge-button {
    position: absolute;
    top: 50%;
    z-index: 50;
    width: 48px;
    height: 48px;
    transform: translateY(-50%);
    border-radius: 999px;
    border: 1px solid rgba(255,255,255,.22);
    background: rgba(15,23,42,.82);
    color: #fff;
    font-size: 28px;
    line-height: 1;
    cursor: pointer;
    backdrop-filter: blur(14px);
    transition: background .2s ease, transform .2s ease, opacity .2s ease;
}

.r3d-edge-button:hover:not(:disabled) {
    background: var(--r3d-primary);
    transform: translateY(-50%) scale(1.04);
}

.r3d-edge-button:disabled {
    opacity: .35;
    cursor: not-allowed;
}

.r3d-edge-prev {
    left: -18px;
}

.r3d-edge-next {
    right: -18px;
}

.r3d-thumbs {
    position: relative;
    z-index: 3;
    margin-top: 14px;
    display: grid;
    grid-auto-flow: column;
    grid-auto-columns: 86px;
    gap: 10px;
    overflow-x: auto;
    padding: 3px 2px 12px;
    scrollbar-width: thin;
}

.r3d-thumb {
    height: 116px;
    padding: 0;
    border: 2px solid transparent;
    border-radius: 12px;
    overflow: hidden;
    background: var(--r3d-paper);
    cursor: pointer;
    transition: border-color .2s ease, transform .2s ease;
}

.r3d-thumb:hover,
.r3d-thumb.is-active {
    border-color: var(--r3d-primary);
    transform: translateY(-2px);
}

.r3d-thumb canvas {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
}

.r3d-loader {
    min-height: 240px;
    border-radius: 24px;
    display: grid;
    place-items: center;
    gap: 12px;
    padding: 28px;
    background: #0f172a;
    color: #fff;
    text-align: center;
}

.r3d-loader-spinner {
    width: 42px;
    height: 42px;
    border-radius: 50%;
    border: 4px solid rgba(255,255,255,.26);
    border-top-color: var(--r3d-primary);
    animation: r3dSpin 1s linear infinite;
}

@keyframes r3dSpin {
    to { transform: rotate(360deg); }
}

.r3d-message {
    border-radius: 18px;
    padding: 18px;
    color: #991b1b;
    background: #fef2f2;
    border: 1px solid #fecaca;
}

@media (max-width: 768px) {
    .r3d-flipbook-wrap {
        margin: 18px auto;
        width: 100%;
    }

    .r3d-viewer {
        border-radius: 20px;
        padding: 12px;
    }

    .r3d-header {
        align-items: flex-start;
        flex-direction: column;
        margin-bottom: 12px;
    }

    .r3d-toolbar {
        width: 100%;
        border-radius: 20px;
        justify-content: center;
    }

    .r3d-btn {
        min-width: 38px;
        min-height: 38px;
        padding: 0 11px;
        font-size: 13px;
    }

    .r3d-book-stage {
        height: var(--r3d-height-mobile);
        max-height: 72vh;
    }

    .r3d-book {
        grid-template-columns: 1fr;
    }

    .r3d-book::before,
    .r3d-page-left,
    .r3d-flipper {
        display: none !important;
    }

    .r3d-page-right {
        border-radius: 18px;
        box-shadow: inset 0 0 0 1px rgba(0,0,0,.06), 0 22px 48px rgba(0,0,0,.24);
    }

    .r3d-edge-prev {
        left: 8px;
    }

    .r3d-edge-next {
        right: 8px;
    }

    .r3d-edge-button {
        width: 42px;
        height: 42px;
        font-size: 24px;
    }

    .r3d-thumbs {
        grid-auto-columns: 72px;
    }

    .r3d-thumb {
        height: 98px;
    }
}

@media (prefers-reduced-motion: reduce) {
    .r3d-flipper.is-active,
    .r3d-flipper.is-backward {
        animation-duration: .01ms;
    }

    .r3d-btn,
    .r3d-thumb,
    .r3d-edge-button {
        transition: none;
    }
}