/* ============================================
   FLIPBOOK DIGITAL - FASE 3 ESTABILIZACIÓN
   Estilo Sunshine Team
   ============================================ */

/* CSS Variables - Paleta Sunshine */
:root {
    /* Colores principales */
    --sunshine-green: #A8D134;
    --sunshine-yellow: #FFD700;
    --sunshine-orange: #FF9933;

    /* Tonos claros */
    --sunshine-green-light: #F0F8E0;
    --sunshine-yellow-light: #FFF9E6;
    --sunshine-orange-light: #FFEDCC;

    /* Gradientes */
    --gradient-sunshine: linear-gradient(135deg, var(--sunshine-green), var(--sunshine-yellow));

    /* Tipografías */
    --font-display: 'Montserrat', sans-serif;
    --font-body: 'Inter', sans-serif;

    /* Sombras */
    --shadow-sm: 0 2px 4px rgba(168, 209, 52, 0.1);
    --shadow-md: 0 4px 12px rgba(168, 209, 52, 0.15);
    --shadow-lg: 0 8px 24px rgba(168, 209, 52, 0.2);
    --shadow-xl: 0 12px 48px rgba(168, 209, 52, 0.25);

    /* Espaciado */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;

    /* Border radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-2xl: 32px;

    /* Transiciones */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* Reset & Base */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-weight: 400;
    line-height: 1.6;
    color: #2d3748;
    background: linear-gradient(180deg,
        var(--sunshine-green-light) 0%,
        var(--sunshine-yellow-light) 50%,
        var(--sunshine-orange-light) 100%
    );
    min-height: 100vh;
    overflow-x: hidden;
}

/* ============================================
   LOADING OVERLAY
   ============================================ */

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg,
        rgba(168, 209, 52, 0.95),
        rgba(255, 215, 0, 0.95)
    );
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.loading-overlay.hidden {
    opacity: 0;
    visibility: hidden;
}

.loading-spinner {
    position: relative;
    width: 80px;
    height: 80px;
}

.spinner-ring {
    position: absolute;
    width: 100%;
    height: 100%;
    border: 4px solid transparent;
    border-top-color: var(--sunshine-green);
    border-radius: 50%;
    animation: spin 1.5s cubic-bezier(0.68, -0.55, 0.265, 1.55) infinite;
}

.spinner-ring:nth-child(2) {
    width: 70%;
    height: 70%;
    top: 15%;
    left: 15%;
    border-top-color: var(--sunshine-yellow);
    animation-delay: 0.2s;
    animation-duration: 1.2s;
}

.spinner-ring:nth-child(3) {
    width: 40%;
    height: 40%;
    top: 30%;
    left: 30%;
    border-top-color: var(--sunshine-orange);
    animation-delay: 0.4s;
    animation-duration: 0.9s;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-text {
    margin-top: var(--spacing-lg);
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 600;
    color: #fff;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

/* ============================================
   MAIN CONTAINER
   ============================================ */

.flipbook-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-lg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

.flipbook-header {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-2xl);
    padding: var(--spacing-md) var(--spacing-lg);
    margin-bottom: var(--spacing-md);
    box-shadow: var(--shadow-md);
    border: 2px solid var(--sunshine-green);
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-md);
}

.flipbook-title {
    font-family: var(--font-display);
    font-size: 1.75rem;
    font-weight: 800;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.title-accent {
    background: var(--gradient-sunshine);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.title-text {
    color: #2d3748;
}

.counter {
    display: flex;
    align-items: center;
    gap: 4px;
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--sunshine-green);
}

.counter-divider {
    color: #cbd5e0;
}

.action-buttons {
    display: flex;
    gap: var(--spacing-xs);
}

.action-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: var(--gradient-sunshine);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.action-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.action-btn:active {
    transform: translateY(0);
}

/* ============================================
   PROGRESS BAR
   ============================================ */

.progress-bar {
    width: 100%;
    height: 6px;
    background: rgba(255, 255, 255, 0.5);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: var(--spacing-md);
    box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.1);
}

.progress-fill {
    height: 100%;
    width: 1.37%;
    background: var(--gradient-sunshine);
    border-radius: 3px;
    transition: width var(--transition-slow) cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 10px rgba(168, 209, 52, 0.5);
}

/* ============================================
   FLIPBOOK VIEWPORT
   ============================================ */

.flipbook-viewport {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.image-display {
    position: relative;
    flex: 1;
    max-width: 900px;
    aspect-ratio: 4 / 3;
    background: white;
    border-radius: var(--radius-2xl);
    overflow: hidden;
    box-shadow: var(--shadow-xl);
    border: 3px solid var(--sunshine-yellow);
}

.image-wrapper {
    position: relative;
    width: 100%;
    height: 100%;
    overflow: hidden;
    cursor: grab;
}

.image-wrapper.panning {
    cursor: grabbing;
}

.main-image {
    width: 100%;
    height: 100%;
    object-fit: contain;
    transition: transform var(--transition-slow) cubic-bezier(0.4, 0, 0.2, 1);
    user-select: none;
    -webkit-user-drag: none;
}

/* Zoom Indicator */
.zoom-indicator {
    position: absolute;
    top: var(--spacing-md);
    right: var(--spacing-md);
    background: rgba(255, 255, 255, 0.95);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 0.875rem;
    color: var(--sunshine-green);
    box-shadow: var(--shadow-md);
    opacity: 0;
    transform: translateY(-10px);
    transition: all var(--transition-normal);
    pointer-events: none;
}

.zoom-indicator.visible {
    opacity: 1;
    transform: translateY(0);
}

/* Pan Hint */
.pan-hint {
    position: absolute;
    bottom: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    background: rgba(0, 0, 0, 0.7);
    color: white;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    opacity: 0;
    transition: opacity var(--transition-normal);
    pointer-events: none;
}

.pan-hint.visible {
    opacity: 1;
}

/* Navigation Buttons */
.nav-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    background: var(--gradient-sunshine);
    border: none;
    border-radius: 50%;
    color: white;
    cursor: pointer;
    transition: all var(--transition-normal);
    flex-shrink: 0;
    box-shadow: var(--shadow-lg);
}

.nav-btn:hover:not(:disabled) {
    transform: scale(1.1);
    box-shadow: var(--shadow-xl);
}

.nav-btn:active:not(:disabled) {
    transform: scale(0.95);
}

.nav-btn:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

.nav-btn-prev svg,
.nav-btn-next svg {
    transition: transform var(--transition-normal);
}

.nav-btn-prev:hover:not(:disabled) svg {
    transform: translateX(-3px);
}

.nav-btn-next:hover:not(:disabled) svg {
    transform: translateX(3px);
}

/* ============================================
   THUMBNAILS SECTION
   ============================================ */

.thumbnails-section {
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    padding: var(--spacing-md);
    box-shadow: var(--shadow-md);
    border: 2px solid var(--sunshine-yellow);
}

.thumbnails-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--spacing-md);
}

.thumbnails-title {
    font-family: var(--font-display);
    font-size: 1.125rem;
    font-weight: 700;
    color: #2d3748;
}

.scroll-hint {
    display: none;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    background: var(--sunshine-yellow);
    border: none;
    border-radius: 50%;
    color: white;
    animation: bounce-hint 2s infinite;
}

@keyframes bounce-hint {
    0%, 20%, 50%, 80%, 100% {
        transform: translateX(0);
    }
    40% {
        transform: translateX(5px);
    }
    60% {
        transform: translateX(-5px);
    }
}

.thumbnails-container {
    position: relative;
}

.thumbnails-track {
    display: flex;
    gap: var(--spacing-sm);
    overflow-x: auto;
    overflow-y: hidden;
    padding: var(--spacing-xs);
    scroll-behavior: smooth;
    -webkit-overflow-scrolling: touch;
    scrollbar-width: thin;
    scrollbar-color: var(--sunshine-green) transparent;
}

.thumbnails-track::-webkit-scrollbar {
    height: 8px;
}

.thumbnails-track::-webkit-scrollbar-track {
    background: rgba(168, 209, 52, 0.1);
    border-radius: 4px;
}

.thumbnails-track::-webkit-scrollbar-thumb {
    background: var(--sunshine-green);
    border-radius: 4px;
}

.thumbnails-track::-webkit-scrollbar-thumb:hover {
    background: #95b82d;
}

.thumbnail {
    position: relative;
    flex-shrink: 0;
    width: 100px;
    height: 75px;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 3px solid transparent;
    cursor: pointer;
    transition: all var(--transition-normal);
    background: #f7fafc;
}

.thumbnail img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-normal);
}

.thumbnail:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-md);
}

.thumbnail:hover img {
    transform: scale(1.1);
}

.thumbnail.active {
    border-color: var(--sunshine-green);
    box-shadow: 0 0 0 4px rgba(168, 209, 52, 0.3);
}

.thumbnail.active::after {
    content: '';
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg,
        rgba(168, 209, 52, 0.2),
        rgba(255, 215, 0, 0.2)
    );
}

/* ============================================
   KEYBOARD HINTS
   ============================================ */

.keyboard-hint {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    justify-content: center;
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    background: rgba(255, 255, 255, 0.6);
    border-radius: var(--radius-lg);
}

.hint-item {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 0.875rem;
    color: #4a5568;
}

.hint-item kbd {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 28px;
    height: 28px;
    padding: 0 var(--spacing-xs);
    background: white;
    border: 2px solid var(--sunshine-green);
    border-radius: 6px;
    font-family: var(--font-display);
    font-weight: 600;
    font-size: 0.75rem;
    color: var(--sunshine-green);
    box-shadow: var(--shadow-sm);
}

/* ============================================
   FULLSCREEN MODE
   ============================================ */

.flipbook-container.fullscreen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    max-width: none;
    padding: var(--spacing-md);
    z-index: 9998;
    background: linear-gradient(180deg,
        var(--sunshine-green-light) 0%,
        var(--sunshine-yellow-light) 50%,
        var(--sunshine-orange-light) 100%
    );
}

.flipbook-container.fullscreen .image-display {
    max-width: 100%;
    height: calc(100vh - 250px);
}

.flipbook-container.fullscreen .thumbnails-section {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.flipbook-container.fullscreen .keyboard-hint {
    display: none;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.main-image.loading {
    animation: fadeIn var(--transition-slow);
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

@media (max-width: 1024px) {
    .flipbook-header {
        flex-wrap: wrap;
    }

    .flipbook-title {
        font-size: 1.5rem;
    }

    .image-display {
        aspect-ratio: 16 / 9;
    }
}

@media (max-width: 768px) {
    .flipbook-container {
        padding: var(--spacing-sm);
    }

    .flipbook-header {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .header-content {
        flex-direction: column;
        text-align: center;
    }

    .flipbook-title {
        font-size: 1.25rem;
    }

    .flipbook-viewport {
        gap: var(--spacing-xs);
    }

    .nav-btn {
        width: 44px;
        height: 44px;
    }

    .nav-btn svg {
        width: 24px;
        height: 24px;
    }

    .image-display {
        aspect-ratio: 1 / 1;
        border-width: 2px;
    }

    .thumbnail {
        width: 70px;
        height: 52px;
    }

    .thumbnails-title {
        font-size: 1rem;
    }

    .scroll-hint {
        display: flex;
    }

    .keyboard-hint {
        display: none;
    }
}

@media (max-width: 480px) {
    .flipbook-title {
        font-size: 1rem;
        flex-direction: column;
        gap: 0.25rem;
    }

    .counter {
        font-size: 1.25rem;
    }

    .action-btn {
        width: 38px;
        height: 38px;
    }

    .thumbnail {
        width: 60px;
        height: 45px;
    }
}

/* ============================================
   PRINT STYLES
   ============================================ */

@media print {
    .loading-overlay,
    .nav-btn,
    .thumbnails-section,
    .action-buttons,
    .progress-bar,
    .keyboard-hint {
        display: none !important;
    }

    .flipbook-container {
        background: white;
    }

    .image-display {
        box-shadow: none;
        border: 1px solid #e2e8f0;
    }
}