/* ========================================
   BANKNOTE COLLECTION - VINTAGE DESIGN
   ======================================== */

:root {
    --color-parchment: #f5f0e6;
    --color-parchment-dark: #e8e0d0;
    --color-sepia: #704214;
    --color-sepia-light: #8b6914;
    --color-gold: #c9a227;
    --color-gold-dark: #9a7b1a;
    --color-ink: #2c1810;
    --color-ink-light: #4a3728;
    --color-cream: #faf8f3;
    --color-border: #d4c4a8;
    --color-shadow: rgba(44, 24, 16, 0.15);
    --font-display: 'Playfair Display', Georgia, serif;
    --font-body: 'Crimson Text', Georgia, serif;
    --font-elegant: 'Cormorant Garamond', Georgia, serif;
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-card: 0 4px 20px var(--color-shadow);
    --shadow-hover: 0 8px 30px rgba(44, 24, 16, 0.25);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
    font-family: var(--font-body);
    background: var(--color-parchment);
    color: var(--color-ink);
    line-height: 1.6;
    min-height: 100vh;
}


/* Auth Overlay */
.auth-overlay {
    position: fixed;
    inset: 0;
    background: linear-gradient(135deg, rgba(44, 24, 16, 0.95), rgba(112, 66, 20, 0.9));
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.5s ease;
}

.auth-overlay.visible {
    opacity: 1;
    visibility: visible;
}

.auth-box {
    background: var(--color-cream);
    padding: 3rem 4rem;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.4);
    border: 2px solid var(--color-gold);
    max-width: 400px;
    animation: fadeInUp 0.6s ease;
}

.auth-box h2 {
    font-family: var(--font-display);
    font-size: 1.8rem;
    color: var(--color-sepia);
    margin-bottom: 0.5rem;
}

.auth-box p {
    color: var(--color-ink-light);
    margin-bottom: 1.5rem;
    font-style: italic;
}

.auth-box input {
    width: 100%;
    padding: 0.8rem 1rem;
    font-size: 1rem;
    font-family: var(--font-body);
    border: 2px solid var(--color-border);
    border-radius: 4px;
    background: var(--color-parchment);
    margin-bottom: 1rem;
    transition: var(--transition-smooth);
}

.auth-box input:focus {
    outline: none;
    border-color: var(--color-gold);
    box-shadow: 0 0 0 3px rgba(201, 162, 39, 0.2);
}

.auth-box button {
    width: 100%;
    padding: 0.8rem 2rem;
    font-family: var(--font-display);
    font-size: 1rem;
    font-weight: 600;
    background: linear-gradient(135deg, var(--color-sepia), var(--color-sepia-light));
    color: var(--color-cream);
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.auth-box button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(112, 66, 20, 0.4);
}

.auth-error {
    color: #c0392b;
    font-size: 0.9rem;
    margin-top: 0.5rem;
    display: none;
}

.auth-error.show { display: block; }


/* Header */
.site-header {
    background: linear-gradient(180deg, var(--color-cream) 0%, var(--color-parchment) 100%);
    border-bottom: 3px solid var(--color-gold);
    padding: 1rem 2rem;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: 0 2px 20px var(--color-shadow);
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
    position: relative;
}

.site-title {
    font-family: var(--font-display);
    font-size: 1.6rem;
    font-weight: 700;
    color: var(--color-sepia);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.site-title span { font-size: 1.4rem; }

/* Navigation */
.main-nav ul {
    list-style: none;
    display: flex;
    gap: 0.5rem;
}

.main-nav a {
    display: block;
    padding: 0.6rem 1.2rem;
    font-family: var(--font-display);
    font-size: 0.95rem;
    color: var(--color-ink-light);
    text-decoration: none;
    border-radius: 4px;
    transition: var(--transition-smooth);
    position: relative;
}

.main-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    width: 0;
    height: 2px;
    background: var(--color-gold);
    transition: var(--transition-smooth);
    transform: translateX(-50%);
}

.main-nav a:hover::after,
.main-nav a.active::after {
    width: 80%;
}

.main-nav a.active {
    color: var(--color-sepia);
    font-weight: 600;
}

/* Search */
.search-box {
    position: relative;
}

.search-box input {
    padding: 0.6rem 1rem 0.6rem 2.5rem;
    font-family: var(--font-body);
    font-size: 0.95rem;
    border: 2px solid var(--color-border);
    border-radius: 25px;
    background: var(--color-parchment);
    width: 220px;
    transition: var(--transition-smooth);
}

.search-box input:focus {
    outline: none;
    border-color: var(--color-gold);
    width: 280px;
}

.search-box::before {
    content: '🔍';
    position: absolute;
    left: 0.8rem;
    top: 50%;
    transform: translateY(-50%);
    font-size: 0.9rem;
    opacity: 0.6;
}


/* Main Content */
.main-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
}

.page-title {
    font-family: var(--font-display);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-sepia);
    text-align: center;
    margin-bottom: 1.5rem;
    position: relative;
}

/* Quick Navigation Slider */
.quick-nav-slider {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    max-width: 100%;
    margin: 0 auto 2rem;
    padding: 0.6rem 0.8rem;
    background: linear-gradient(135deg, var(--color-cream), var(--color-parchment-dark));
    border: 1px solid var(--color-border);
    border-radius: 30px;
    box-shadow: inset 0 1px 3px rgba(0,0,0,0.05);
    position: sticky;
    top: 70px;
    z-index: 90;
    transition: var(--transition-smooth);
}

.quick-nav-slider.stuck {
    box-shadow: 0 4px 20px var(--color-shadow);
}

.slider-track {
    display: flex;
    gap: 0.4rem;
    overflow-x: auto;
    scroll-behavior: smooth;
    scrollbar-width: none;
    -ms-overflow-style: none;
    flex: 1;
    padding: 0.2rem 0;
}

.slider-track::-webkit-scrollbar {
    display: none;
}

.slider-item {
    flex-shrink: 0;
    padding: 0.4rem 0.9rem;
    font-family: var(--font-display);
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-ink-light);
    background: transparent;
    border: 1px solid transparent;
    border-radius: 20px;
    cursor: pointer;
    transition: var(--transition-smooth);
    white-space: nowrap;
}

.slider-item:hover {
    background: var(--color-parchment);
    border-color: var(--color-border);
    color: var(--color-sepia);
}

.slider-item.active {
    background: var(--color-sepia);
    color: var(--color-cream);
    border-color: var(--color-sepia);
    box-shadow: 0 2px 8px rgba(112, 66, 20, 0.3);
}

.slider-arrow {
    flex-shrink: 0;
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-parchment);
    border: 1px solid var(--color-border);
    border-radius: 50%;
    font-size: 1.2rem;
    color: var(--color-ink-light);
    cursor: pointer;
    transition: var(--transition-smooth);
}

.slider-arrow:hover {
    background: var(--color-sepia);
    color: var(--color-cream);
    border-color: var(--color-sepia);
}

.page-subtitle {
    font-family: var(--font-elegant);
    font-size: 1.2rem;
    color: var(--color-ink-light);
    text-align: center;
    font-style: italic;
    margin-bottom: 2rem;
}

.collection-stats {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.stat-item {
    text-align: center;
    padding: 1rem 2rem;
    background: var(--color-cream);
    border-radius: 8px;
    border: 1px solid var(--color-border);
}

.stat-number {
    font-family: var(--font-display);
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-gold-dark);
}

.stat-label {
    font-size: 0.85rem;
    color: var(--color-ink-light);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* Era Groups */
.era-group {
    margin-bottom: 3rem;
    animation: fadeInUp 0.6s ease;
}

.era-header {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    background: linear-gradient(135deg, var(--color-cream), var(--color-parchment-dark));
    border: 2px solid var(--color-border);
    border-radius: 12px 12px 0 0;
    border-bottom: 3px solid var(--color-gold);
}

.era-coat {
    width: 60px;
    height: 60px;
    object-fit: contain;
    background: white;
    border-radius: 50%;
    padding: 5px;
    border: 2px solid var(--color-gold);
    box-shadow: 0 2px 10px var(--color-shadow);
}

.era-info h2 {
    font-family: var(--font-display);
    font-size: 1.4rem;
    color: var(--color-sepia);
    margin-bottom: 0.2rem;
}

.era-info span {
    font-size: 0.9rem;
    color: var(--color-ink-light);
}

.era-body {
    background: var(--color-cream);
    border: 2px solid var(--color-border);
    border-top: none;
    border-radius: 0 0 12px 12px;
    padding: 1.5rem;
}


/* Banknote Grid */
.banknote-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 1.5rem;
}

/* Banknote Card */
.banknote-card {
    background: var(--color-parchment);
    border-radius: 10px;
    overflow: hidden;
    box-shadow: var(--shadow-card);
    cursor: pointer;
    transition: var(--transition-smooth);
    border: 1px solid var(--color-border);
    position: relative;
    isolation: isolate;
}

.banknote-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.banknote-card.not-owned {
    opacity: 0.4;
    filter: grayscale(0.5);
    cursor: default;
}

.banknote-card.not-owned:hover {
    transform: none;
    box-shadow: var(--shadow-card);
}

/* Card Image Container with Flip */
.card-image-container {
    position: relative;
    width: 100%;
    padding-bottom: 62%;
    perspective: 1000px;
    background: white;
    overflow: hidden;
}

.card-flipper {
    position: absolute;
    inset: 0;
    transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
    transform-style: preserve-3d;
}

.banknote-card:not(.not-owned):hover .card-flipper {
    transform: rotateY(180deg);
}

.card-front, .card-back {
    position: absolute;
    inset: 0;
    backface-visibility: hidden;
    -webkit-backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
}

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

.card-front img, .card-back img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

/* Card Info */
.card-info {
    padding: 0.8rem 1rem;
    background: linear-gradient(180deg, var(--color-parchment) 0%, var(--color-parchment-dark) 100%);
    border-top: 1px solid var(--color-border);
    height: 70px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    overflow: hidden;
}

.card-denomination {
    font-family: var(--font-display);
    font-size: 1.3rem;
    font-weight: 700;
    color: var(--color-sepia);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.card-details {
    font-size: 0.85rem;
    color: var(--color-ink-light);
    margin-top: 0.2rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.card-year {
    display: inline-block;
    background: var(--color-gold);
    color: white;
    padding: 0.1rem 0.5rem;
    border-radius: 3px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-left: 0.3rem;
}


/* Modal */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(44, 24, 16, 0.9);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-smooth);
    padding: 1rem;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--color-cream);
    border-radius: 12px;
    max-width: 900px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
    border: 3px solid var(--color-gold);
    transform: scale(0.9);
    transition: transform 0.3s ease;
    position: relative;
}

.modal-overlay.active .modal-content {
    transform: scale(1);
}

.modal-close {
    position: sticky;
    top: 0;
    right: 0;
    float: right;
    background: var(--color-cream);
    border: none;
    font-size: 2rem;
    color: var(--color-ink-light);
    cursor: pointer;
    line-height: 1;
    transition: var(--transition-smooth);
    z-index: 10;
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 0 9px 0 8px;
    border-bottom: 1px solid var(--color-border);
    border-left: 1px solid var(--color-border);
}

.modal-close:hover {
    color: var(--color-sepia);
    background: var(--color-parchment);
}

.modal-header {
    padding: 1.5rem 2rem;
    padding-right: 60px;
    background: linear-gradient(135deg, var(--color-parchment), var(--color-parchment-dark));
    border-bottom: 2px solid var(--color-gold);
}

.modal-title-block h2 {
    font-family: var(--font-display);
    font-size: 1.8rem;
    color: var(--color-sepia);
}

.modal-title-block p {
    color: var(--color-ink-light);
    font-style: italic;
}

.modal-coat {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 2rem;
    background: var(--color-parchment);
    border-bottom: 1px solid var(--color-border);
}

.modal-coat img {
    width: 50px;
    height: 50px;
    object-fit: contain;
}

.modal-coat span {
    font-family: var(--font-elegant);
    font-size: 1.1rem;
    color: var(--color-ink-light);
    font-style: italic;
}

.modal-images {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    padding: 1.5rem 2rem;
}

.modal-image-wrapper {
    position: relative;
    overflow: hidden;
    border-radius: 8px;
    border: 2px solid var(--color-border);
}

.modal-image-wrapper img {
    width: 100%;
    height: auto;
    display: block;
}

.modal-description {
    padding: 1.5rem 2rem;
    border-top: 1px solid var(--color-border);
}

.modal-description h3 {
    font-family: var(--font-display);
    font-size: 1.2rem;
    color: var(--color-sepia);
    margin-bottom: 0.8rem;
}

.modal-description p {
    color: var(--color-ink-light);
    line-height: 1.8;
}


/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* Responsive */
@media (max-width: 900px) {
    .modal-images {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    .site-header {
        padding: 0.5rem 1rem;
    }
    
    .header-content {
        flex-wrap: nowrap;
        gap: 0.5rem;
    }
    
    .site-title {
        font-size: 1rem;
        white-space: nowrap;
    }
    
    .site-title span {
        font-size: 1rem;
    }
    
    .search-box input {
        width: 120px;
        padding: 0.4rem 0.6rem 0.4rem 2rem;
        font-size: 0.85rem;
    }
    
    .search-box input:focus {
        width: 140px;
    }
    
    .search-box::before {
        left: 0.5rem;
        font-size: 0.8rem;
    }
    
    .nav-toggle {
        padding: 0.3rem 0.5rem;
        font-size: 1.2rem;
    }
    
    .page-title {
        font-size: 1.8rem;
    }
    
    .quick-nav-slider {
        margin: 0 -1rem 1.5rem;
        border-radius: 0;
        border-left: none;
        border-right: none;
    }
    
    .slider-item {
        font-size: 0.8rem;
        padding: 0.35rem 0.7rem;
    }
    
    .slider-arrow {
        width: 24px;
        height: 24px;
        font-size: 1rem;
    }
    
    .banknote-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1rem;
    }
    
    .era-header {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .main-content {
        padding: 1rem;
    }
    
    .banknote-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 0.75rem;
    }
    
    .collection-stats {
        gap: 1rem;
    }
    
    .stat-item {
        padding: 0.8rem 1.2rem;
    }
    
    .card-denomination {
        font-size: 1rem;
    }
    
    .card-info {
        padding: 0.5rem 0.6rem;
        height: 55px;
    }
}

/* Mobile Nav Toggle */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    padding: 0.5rem;
    color: var(--color-ink);
}

@media (max-width: 768px) {
    .nav-toggle {
        display: block;
        order: 2;
    }
    
    .site-title {
        order: 1;
        flex: 1;
    }
    
    .search-box {
        order: 3;
    }
    
    .main-nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--color-cream);
        border-bottom: 2px solid var(--color-gold);
        box-shadow: 0 4px 10px var(--color-shadow);
    }
    
    .main-nav.open {
        display: block;
    }
    
    .main-nav ul {
        flex-direction: column;
        width: 100%;
        padding: 0.5rem 0;
    }
    
    .main-nav a {
        display: block;
        text-align: center;
        padding: 0.8rem;
    }
}

/* Loading State */
.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 3rem;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid var(--color-border);
    border-top-color: var(--color-gold);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Empty State */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--color-ink-light);
}

.empty-state h3 {
    font-family: var(--font-display);
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

/* Owned Badge */
.owned-badge {
    position: absolute;
    top: 8px;
    right: 8px;
    background: var(--color-gold);
    color: white;
    font-size: 0.7rem;
    padding: 0.2rem 0.5rem;
    border-radius: 3px;
    font-weight: 600;
    z-index: 5;
}


/* Paper texture background */
body::before {
    content: '';
    position: fixed;
    inset: 0;
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 400 400' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noiseFilter'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noiseFilter)'/%3E%3C/svg%3E");
    opacity: 0.03;
    pointer-events: none;
    z-index: -1;
}

/* Decorative border for main content */
.main-content::before {
    content: '';
    position: absolute;
    top: 1rem;
    left: 1rem;
    right: 1rem;
    bottom: 1rem;
    border: 1px solid var(--color-border);
    border-radius: 8px;
    pointer-events: none;
    opacity: 0.3;
}

.main-content {
    position: relative;
}

/* Card hover glow effect */
.banknote-card:not(.not-owned)::before {
    content: '';
    position: absolute;
    inset: -2px;
    background: linear-gradient(135deg, var(--color-gold), transparent, var(--color-gold));
    border-radius: 12px;
    opacity: 0;
    transition: opacity 0.3s ease;
    z-index: -1;
}

.banknote-card:not(.not-owned):hover::before {
    opacity: 0.3;
}

/* Smooth scroll */
html {
    scroll-behavior: smooth;
}

/* Focus styles for accessibility */
a:focus, button:focus, input:focus {
    outline: 2px solid var(--color-gold);
    outline-offset: 2px;
}

/* Selection color */
::selection {
    background: var(--color-gold);
    color: white;
}

/* Footer */
.site-footer {
    text-align: center;
    padding: 2rem;
    margin-top: 3rem;
    border-top: 1px solid var(--color-border);
    color: var(--color-ink-light);
    font-size: 0.9rem;
}

.site-footer a {
    color: var(--color-sepia);
    text-decoration: none;
}

/* Scroll to top button */
.scroll-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--color-sepia);
    color: white;
    border: none;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition-smooth);
    box-shadow: var(--shadow-card);
    z-index: 50;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
}

.scroll-top:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-hover);
}

/* Staggered animation for cards */
.banknote-card {
    animation: fadeInUp 0.5s ease backwards;
}

.banknote-card:nth-child(1) { animation-delay: 0.05s; }
.banknote-card:nth-child(2) { animation-delay: 0.1s; }
.banknote-card:nth-child(3) { animation-delay: 0.15s; }
.banknote-card:nth-child(4) { animation-delay: 0.2s; }
.banknote-card:nth-child(5) { animation-delay: 0.25s; }
.banknote-card:nth-child(6) { animation-delay: 0.3s; }
.banknote-card:nth-child(7) { animation-delay: 0.35s; }
.banknote-card:nth-child(8) { animation-delay: 0.4s; }

/* Touch device adjustments */
@media (hover: none) {
    .banknote-card:not(.not-owned):hover .card-flipper {
        transform: none;
    }
    
    .banknote-card:hover {
        transform: none;
    }
}