/* ========================================
   CSS VARIABLES & THEME CONFIGURATION
   ======================================== */

:root {
    /* Cores principais */
    --color-primary: #4285f4;
    --color-primary-dark: #3367d6;
    --color-secondary: #34a853;
    --color-accent: #fbbc04;
    --color-danger: #ea4335;
    
    /* Cores neutras */
    --color-white: #ffffff;
    --color-gray-50: #f8f9fa;
    --color-gray-100: #f1f3f4;
    --color-gray-200: #e8eaed;
    --color-gray-300: #dadce0;
    --color-gray-400: #bdc1c6;
    --color-gray-500: #9aa0a6;
    --color-gray-600: #80868b;
    --color-gray-700: #5f6368;
    --color-gray-800: #3c4043;
    --color-gray-900: #202124;
    
    /* Sombras */
    --shadow-sm: 0 1px 2px 0 rgba(60, 64, 67, 0.1), 0 1px 3px 1px rgba(60, 64, 67, 0.1);
    --shadow-md: 0 1px 3px 0 rgba(60, 64, 67, 0.1), 0 4px 8px 3px rgba(60, 64, 67, 0.1);
    --shadow-lg: 0 1px 3px 0 rgba(60, 64, 67, 0.1), 0 6px 10px 4px rgba(60, 64, 67, 0.15);
    --shadow-xl: 0 2px 6px 2px rgba(60, 64, 67, 0.15), 0 1px 2px 0 rgba(60, 64, 67, 0.3);
    
    /* Tipografia */
    --font-family-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Arial, sans-serif;
    --font-size-xs: 0.75rem;     /* 12px */
    --font-size-sm: 0.875rem;    /* 14px */
    --font-size-base: 1rem;      /* 16px */
    --font-size-lg: 1.125rem;    /* 18px */
    --font-size-xl: 1.25rem;     /* 20px */
    --font-size-2xl: 1.5rem;     /* 24px */
    --font-size-3xl: 1.875rem; /* 30px */
    --font-size-4xl: 2.25rem;   /* 36px */
    
    /* Espaçamento */
    --spacing-xs: 0.25rem;  /* 4px */
    --spacing-sm: 0.5rem;   /* 8px */
    --spacing-md: 1rem;     /* 16px */
    --spacing-lg: 1.5rem;   /* 24px */
    --spacing-xl: 2rem;     /* 32px */
    --spacing-2xl: 2.5rem;  /* 40px */
    --spacing-3xl: 3rem;    /* 48px */
    
    /* Bordas */
    --border-radius-sm: 0.375rem;
    --border-radius-md: 0.5rem;
    --border-radius-lg: 0.75rem;
    --border-radius-xl: 1rem;
    --border-radius-full: 9999px;
    
    /* Transições */
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
    
    /* Z-index */
    --z-index-dropdown: 1000;
    --z-index-sticky: 1020;
    --z-index-fixed: 1030;
    --z-index-modal-backdrop: 1040;
    --z-index-modal: 1050;
    --z-index-popover: 1060;
    --z-index-tooltip: 1070;
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --color-primary: #8ab4f8;
        --color-primary-dark: #7baaf7;
        --color-gray-50: #202124;
        --color-gray-100: #292a2d;
        --color-gray-200: #3c4043;
        --color-gray-300: #5f6368;
        --color-gray-400: #80868b;
        --color-gray-500: #9aa0a6;
        --color-gray-600: #bdc1c6;
        --color-gray-700: #dadce0;
        --color-gray-800: #e8eaed;
        --color-gray-900: #f8f9fa;
        --color-white: #202124;
        
        --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.3);
        --shadow-md: 0 1px 3px 0 rgba(0, 0, 0, 0.3), 0 4px 8px 3px rgba(0, 0, 0, 0.3);
        --shadow-lg: 0 1px 3px 0 rgba(0, 0, 0, 0.3), 0 6px 10px 4px rgba(0, 0, 0, 0.35);
        --shadow-xl: 0 2px 6px 2px rgba(0, 0, 0, 0.35), 0 1px 2px 0 rgba(0, 0, 0, 0.5);
    }
}

/* ========================================
   RESET & BASE STYLES
   ======================================== */

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

* {
    margin: 0;
    padding: 0;
}

html {
    font-size: 16px;
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-gray-900);
    background-color: var(--color-gray-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

img,
picture,
video,
canvas,
svg {
    display: block;
    max-width: 100%;
    height: auto;
}

input,
button,
textarea,
select {
    font: inherit;
}

button {
    cursor: pointer;
    border: none;
    background: none;
}

ul[role="list"],
ol[role="list"] {
    list-style: none;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ========================================
   UTILITIES
   ======================================== */

.visually-hidden {
    position: absolute !important;
    width: 1px !important;
    height: 1px !important;
    padding: 0 !important;
    margin: -1px !important;
    overflow: hidden !important;
    clip: rect(0, 0, 0, 0) !important;
    white-space: nowrap !important;
    border: 0 !important;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   TYPOGRAPHY
   ======================================== */

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-gray-900);
}

h1 {
    font-size: var(--font-size-4xl);
}

h2 {
    font-size: var(--font-size-3xl);
}

h3 {
    font-size: var(--font-size-2xl);
}

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

.header {
    background-color: var(--color-white);
    box-shadow: var(--shadow-sm);
    padding: var(--spacing-lg) 0;
    position: sticky;
    top: 0;
    z-index: var(--z-index-sticky);
}

.header__title {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.header__subtitle {
    color: var(--color-gray-600);
    font-size: var(--font-size-lg);
}

/* ========================================
   MAIN CONTENT
   ======================================== */

.main {
    min-height: calc(100vh - 120px);
    padding: var(--spacing-2xl) 0;
}

/* ========================================
   ADD ALBUM SECTION
   ======================================== */

.add-album {
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.add-album__form {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: var(--spacing-lg);
    align-items: end;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.input-group__label {
    font-weight: 500;
    color: var(--color-gray-700);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.input-group__input {
    padding: var(--spacing-md);
    border: 2px solid var(--color-gray-300);
    border-radius: var(--border-radius-md);
    font-size: var(--font-size-base);
    transition: border-color var(--transition-fast);
    background-color: var(--color-white);
    color: var(--color-gray-900);
}

.input-group__input:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px rgba(66, 133, 244, 0.1);
}

.input-group__help {
    font-size: var(--font-size-sm);
    color: var(--color-gray-500);
}

/* ========================================
   BUTTONS
   ======================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius-md);
    font-weight: 500;
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn--primary {
    background-color: var(--color-primary);
    color: var(--color-white);
    box-shadow: var(--shadow-sm);
}

.btn--primary:hover:not(:disabled) {
    background-color: var(--color-primary-dark);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

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

.btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none !important;
}

/* ========================================
   SECTIONS
   ======================================== */

.section__title {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
    color: var(--color-gray-900);
}

/* ========================================
   ALBUMS GRID
   ======================================== */

.albums__grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-2xl);
}

.album-card {
    background-color: var(--color-white);
    border-radius: var(--border-radius-lg);
    box-shadow: var(--shadow-md);
    overflow: hidden;
    transition: all var(--transition-normal);
    cursor: pointer;
}

.album-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.album-card__image {
    width: 100%;
    height: 200px;
    object-fit: cover;
    background-color: var(--color-gray-200);
}

.album-card__content {
    padding: var(--spacing-lg);
}

.album-card__title {
    font-size: var(--font-size-lg);
    font-weight: 600;
    color: var(--color-gray-900);
    margin-bottom: var(--spacing-xs);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.album-card__count {
    color: var(--color-gray-600);
    font-size: var(--font-size-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ========================================
   LOADING STATES
   ======================================== */

.loading {
    text-align: center;
    padding: var(--spacing-3xl);
}

.loading__spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--color-gray-300);
    border-top-color: var(--color-primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

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

.loading__text {
    color: var(--color-gray-600);
    font-size: var(--font-size-base);
}

.loading__progress {
    margin-top: var(--spacing-md);
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
    text-align: center;
}

.loading__progress span {
    font-weight: 600;
    color: var(--color-primary);
}

/* ========================================
   EMPTY STATE
   ======================================== */

.empty-state {
    text-align: center;
    padding: var(--spacing-3xl);
    color: var(--color-gray-600);
}

.empty-state__icon {
    font-size: 4rem;
    margin-bottom: var(--spacing-lg);
    opacity: 0.5;
}

.empty-state__title {
    font-size: var(--font-size-xl);
    margin-bottom: var(--spacing-sm);
    color: var(--color-gray-700);
}

.empty-state__text {
    font-size: var(--font-size-base);
}

/* ========================================
   MODAL
   ======================================== */

.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: var(--z-index-modal);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

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

.modal__backdrop {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(4px);
}

.modal__content {
    position: relative;
    background-color: var(--color-white);
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-xl);
    max-width: 90vw;
    max-height: 90vh;
    width: 100%;
    overflow: hidden;
    transform: scale(0.9);
    transition: transform var(--transition-normal);
}

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

.modal__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-lg);
    border-bottom: 1px solid var(--color-gray-200);
    background-color: var(--color-gray-50);
}

.modal__title {
    font-size: var(--font-size-xl);
    color: var(--color-gray-900);
}

.modal__close {
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-full);
    background-color: var(--color-white);
    color: var(--color-gray-600);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.modal__close:hover {
    background-color: var(--color-gray-100);
    color: var(--color-gray-900);
}

/* ========================================
   CAROUSEL
   ======================================== */

.carousel {
    position: relative;
    width: 100%;
    height: 70vh;
    background-color: var(--color-gray-900);
}

.carousel__container {
    width: 100%;
    height: 100%;
    overflow: hidden;
    position: relative;
}

.carousel__track {
    display: flex;
    height: 100%;
    transition: transform var(--transition-normal);
}

.carousel__slide {
    min-width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.carousel__image {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border-radius: var(--border-radius-sm);
}

.carousel__nav {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    background-color: rgba(255, 255, 255, 0.9);
    color: var(--color-gray-900);
    width: 50px;
    height: 50px;
    border-radius: var(--border-radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-lg);
    transition: all var(--transition-fast);
    z-index: 10;
    backdrop-filter: blur(10px);
}

.carousel__nav:hover {
    background-color: var(--color-white);
    transform: translateY(-50%) scale(1.1);
}

.carousel__nav--prev {
    left: var(--spacing-lg);
}

.carousel__nav--next {
    right: var(--spacing-lg);
}

.carousel__indicators {
    position: absolute;
    bottom: var(--spacing-lg);
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: var(--spacing-xs);
    z-index: 10;
}

.carousel__indicator {
    width: 12px;
    height: 12px;
    border-radius: var(--border-radius-full);
    background-color: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.carousel__indicator--active {
    background-color: var(--color-white);
    transform: scale(1.2);
}

/* ========================================
   TOAST NOTIFICATIONS
   ======================================== */

.toast-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: var(--z-index-tooltip);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.toast {
    background-color: var(--color-white);
    color: var(--color-gray-900);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius-md);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
    min-width: 300px;
    animation: slideIn var(--transition-normal);
    border-left: 4px solid var(--color-primary);
}

.toast--success {
    border-left-color: var(--color-secondary);
}

.toast--error {
    border-left-color: var(--color-danger);
}

.toast--warning {
    border-left-color: var(--color-accent);
}

@keyframes slideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.toast__icon {
    font-size: var(--font-size-lg);
}

.toast__content {
    flex: 1;
}

.toast__title {
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.toast__message {
    font-size: var(--font-size-sm);
    color: var(--color-gray-600);
}

.toast__close {
    color: var(--color-gray-500);
    transition: color var(--transition-fast);
}

.toast__close:hover {
    color: var(--color-gray-900);
}

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

/* Mobile first approach - default styles are for mobile */

/* Tablets (768px and up) */
@media (min-width: 768px) {
    .container {
        padding: 0 var(--spacing-lg);
    }
    
    .add-album__form {
        grid-template-columns: 1fr auto;
        gap: var(--spacing-xl);
    }
    
    .albums__grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
        gap: var(--spacing-xl);
    }
    
    .carousel {
        height: 80vh;
    }
    
    .carousel__nav {
        width: 60px;
        height: 60px;
        font-size: var(--font-size-xl);
    }
}

/* Desktop (1024px and up) */
@media (min-width: 1024px) {
    .container {
        max-width: 1200px;
        padding: 0 var(--spacing-xl);
    }
    
    .albums__grid {
        grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    }
    
    .carousel {
        height: 85vh;
    }
    
    .modal__content {
        max-width: 80vw;
        max-height: 85vh;
    }
}

/* Large screens (1440px and up) */
@media (min-width: 1440px) {
    .albums__grid {
        grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    }
    
    .carousel {
        height: 90vh;
    }
}

/* ========================================
   ACCESSIBILITY IMPROVEMENTS
   ======================================== */

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
    
    html {
        scroll-behavior: auto;
    }
}

/* Focus visible for keyboard navigation */
:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --color-gray-300: #000;
        --color-gray-600: #000;
        --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.8);
        --shadow-md: 0 1px 3px 0 rgba(0, 0, 0, 0.8), 0 4px 8px 3px rgba(0, 0, 0, 0.8);
    }
}