*,
*::before,
*::after {
    box-sizing: border-box;
}

html,
body {
    margin: 0;
    width: 100%;
    height: 100%;
}

body {
    font-family: Inter, Arial, Helvetica, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    overflow: hidden;
    position: relative;
}

body.has-background-image {
    background-image: none;
}

body.no-background-image {
    background-image: none;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0);
    pointer-events: none;
    z-index: 0;
}

.slideshow-shell {
    position: relative;
    z-index: 1;
    width: 100vw;
    height: 100vh;
    display: grid;
    place-items: center;
}

.back-link {
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 5;
    padding: 0.5rem 0.85rem;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    background: var(--surface-strong);
    color: var(--text-color);
    text-decoration: none;
}

.back-link:hover,
.back-link:focus-visible {
    color: var(--accent-hover);
    background: rgba(var(--accent-rgb), 0.12);
}

.message-box {
    width: min(760px, calc(100vw - 2rem));
    border-radius: 16px;
    border: 1px solid var(--border-color);
    background: var(--surface-strong);
    padding: 1.2rem;
    box-shadow: 0 12px 34px rgba(0, 0, 0, 0.56);
}

.message-box h1 {
    margin: 0 0 0.5rem;
    font-size: clamp(1.2rem, 3vw, 1.7rem);
}

.message-box p {
    margin: 0.3rem 0 0;
    color: var(--text-muted);
}

.slideshow-stage {
    position: relative;
    width: 100vw;
    height: 100vh;
    display: grid;
    place-items: center;
    background: rgba(0, 0, 0, 0.5);
}

#slideshowImage {
    width: 100vw;
    height: 100vh;
    max-width: 100vw;
    max-height: 100vh;
    object-fit: contain;
    transition: opacity 0.4s ease;
}

#slideshowImage.is-fading {
    opacity: 0.14;
}

.overlay-top {
    position: absolute;
    top: 1rem;
    left: 50%;
    transform: translateX(-50%);
    min-width: min(88vw, 280px);
    max-width: min(92vw, 980px);
    border-radius: 14px;
    border: 1px solid var(--border-color);
    background: var(--surface-color);
    backdrop-filter: blur(3px);
    text-align: center;
    padding: 0.55rem 1rem 0.6rem;
    z-index: 3;
}

.overlay-album {
    margin: 0;
    font-size: clamp(1rem, 2.5vw, 1.25rem);
    font-weight: 700;
}

.overlay-counter {
    position: absolute;
    bottom: 1rem;
    left: 50%;
    transform: translateX(-50%);
    margin: 0;
    padding: 0.42rem 0.84rem;
    border-radius: 999px;
    border: 1px solid var(--border-color);
    background: var(--surface-strong);
    z-index: 3;
}

.overlay-progress {
    position: absolute;
    bottom: 0.48rem;
    left: 50%;
    transform: translateX(-50%);
    width: min(260px, 62vw);
    height: 6px;
    border-radius: 999px;
    background: rgba(var(--accent-rgb), 0.16);
    border: 1px solid rgba(var(--accent-rgb), 0.35);
    overflow: hidden;
    z-index: 3;
}

.overlay-progress-bar {
    display: block;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, var(--accent-hover), var(--accent-color));
    transform-origin: left center;
    transform: scaleX(1);
}

.fullscreen-hint {
    position: absolute;
    right: 1rem;
    bottom: 1rem;
    border: 1px solid var(--border-color);
    border-radius: 999px;
    background: var(--surface-strong);
    color: var(--text-color);
    padding: 0.52rem 0.9rem;
    cursor: pointer;
    z-index: 4;
}

.fullscreen-hint:hover,
.fullscreen-hint:focus-visible {
    color: var(--accent-hover);
    background: rgba(var(--accent-rgb), 0.15);
}

.fullscreen-hint.is-hidden {
    display: none;
}

.slideshow-modal {
    position: fixed;
    inset: 0;
    z-index: 20;
    display: grid;
    place-items: center;
    padding: 1rem;
    background: rgba(0, 0, 0, 0.74);
    backdrop-filter: blur(3px);
}

.slideshow-modal.is-hidden {
    display: none;
}

.slideshow-modal-card {
    width: min(720px, calc(100vw - 1.2rem));
    border-radius: 16px;
    border: 1px solid var(--border-color);
    background: rgba(8, 8, 8, 0.93);
    box-shadow: 0 16px 36px rgba(0, 0, 0, 0.58);
    padding: 1rem;
}

.slideshow-modal-card h2 {
    margin: 0 0 0.45rem;
    color: var(--text-color);
}

.slideshow-modal-card p {
    margin: 0 0 0.9rem;
    color: var(--text-muted);
}

.slideshow-config-row {
    display: grid;
    gap: 0.4rem;
    margin-bottom: 0.85rem;
}

.slideshow-config-row label {
    color: var(--text-color);
    font-weight: 700;
}

.slideshow-config-row select {
    width: 100%;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background: rgba(0, 0, 0, 0.58);
    color: var(--text-color);
    padding: 0.55rem 0.65rem;
    font: inherit;
}

.slideshow-config-fieldset {
    margin: 0;
    padding: 0.75rem;
    border: 1px solid rgba(var(--accent-rgb), 0.35);
    border-radius: 12px;
    display: grid;
    gap: 0.55rem;
}

.slideshow-config-fieldset legend {
    color: var(--text-color);
    padding: 0 0.4rem;
    font-weight: 700;
}

.slideshow-config-fieldset label {
    display: flex;
    gap: 0.5rem;
    align-items: flex-start;
    color: var(--text-muted);
}

.slideshow-config-fieldset input[type="radio"] {
    margin-top: 0.18rem;
}

.slideshow-config-actions {
    margin-top: 0.9rem;
    display: flex;
    justify-content: flex-end;
}

.slideshow-start-btn {
    border: 1px solid var(--border-color);
    border-radius: 10px;
    background: rgba(var(--accent-rgb), 0.1);
    color: var(--text-color);
    padding: 0.55rem 0.9rem;
    font: inherit;
    font-weight: 700;
    cursor: pointer;
}

.slideshow-start-btn:hover,
.slideshow-start-btn:focus-visible {
    color: var(--accent-hover);
    background: rgba(var(--accent-rgb), 0.18);
}

@media (max-width: 640px) {
    .back-link {
        top: 0.55rem;
        left: 0.55rem;
        padding: 0.45rem 0.7rem;
        font-size: 0.9rem;
    }

    .overlay-top {
        top: 0.7rem;
        min-width: auto;
        width: calc(100vw - 1rem);
        padding: 0.5rem 0.7rem 0.55rem;
    }

    .overlay-counter {
        bottom: 0.7rem;
        font-size: 0.9rem;
    }

    .overlay-progress {
        bottom: 0.34rem;
        width: min(230px, 68vw);
    }

    .fullscreen-hint {
        right: 0.55rem;
        bottom: 0.55rem;
        font-size: 0.9rem;
    }

    .slideshow-modal-card {
        padding: 0.85rem;
    }
}

@media (prefers-reduced-motion: reduce) {
    #slideshowImage {
        transition: none;
    }
}