/**
 * FILE: /assets/css/frontend.css
 * Core CSS for AI Tools Directory Frontend
 */

/* ==========================================================================
   Design Tokens (CSS Variables)
   These can be overridden by inline styles from the settings database.
   ========================================================================== */
   :root {
    /* Colors - Brand */
    --color-primary: #3B5BDB;
    --color-primary-dark: #2F4AC0;
    --color-secondary: #495057;
    
    /* Colors - Surface */
    --color-background: #F8F9FA;
    --color-card-bg: #FFFFFF;
    --color-header-bg: #FFFFFF;
    --color-footer-bg: #F1F3F5;
    
    /* Colors - Text */
    --color-text-primary: #212529;
    --color-text-secondary: #6C757D;
    --color-link: #3B5BDB;
    
    /* Colors - UI */
    --color-border: #DEE2E6;
    --color-border-hover: #CED4DA;
    --color-error: #FA5252;
    --color-success: #40C057;
    --color-warning: #FCC419;

    /* Typography */
    --font-family-base: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-size-base: 16px;
    --line-height-base: 1.6;

    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 16px;
    --spacing-lg: 24px;
    --spacing-xl: 32px;
    --spacing-2xl: 48px;
    --spacing-3xl: 64px;

    /* Borders & Shadows */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 6px rgba(0,0,0,0.05), 0 1px 3px rgba(0,0,0,0.03);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.05), 0 4px 6px rgba(0,0,0,0.03);
    --transition-base: 0.2s ease-in-out;
}

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

body {
    font-family: var(--font-family-base);
    font-size: var(--font-size-base);
    line-height: var(--line-height-base);
    color: var(--color-text-primary);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: var(--color-link);
    text-decoration: none;
    transition: color var(--transition-base);
}

a:hover {
    color: var(--color-primary-dark);
}

button, input, select, textarea {
    font-family: inherit;
    font-size: inherit;
}

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

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

/* ==========================================================================
   Typography & Prose (Rich Text)
   ========================================================================== */
h1, h2, h3, h4, h5, h6 {
    color: var(--color-text-primary);
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
}

.prose {
    color: var(--color-text-primary);
    font-size: 1.125rem;
    line-height: 1.7;
}

.prose p { margin-bottom: var(--spacing-lg); }
.prose h2 { font-size: 2rem; margin-top: var(--spacing-2xl); margin-bottom: var(--spacing-md); }
.prose h3 { font-size: 1.5rem; margin-top: var(--spacing-xl); margin-bottom: var(--spacing-sm); }
.prose ul, .prose ol { margin-bottom: var(--spacing-lg); padding-left: var(--spacing-xl); }
.prose li { margin-bottom: var(--spacing-xs); }
.prose a { text-decoration: underline; text-decoration-color: var(--color-border); text-underline-offset: 4px; }
.prose a:hover { text-decoration-color: var(--color-primary); }
.prose blockquote {
    border-left: 4px solid var(--color-primary);
    padding-left: var(--spacing-md);
    font-style: italic;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 10px 20px;
    font-weight: 600;
    border-radius: var(--border-radius-md);
    border: none;
    cursor: pointer;
    text-align: center;
    transition: all var(--transition-base);
    text-decoration: none;
}

.btn--primary {
    background-color: var(--color-primary);
    color: #fff;
}

.btn--primary:hover {
    background-color: var(--color-primary-dark);
    color: #fff;
    transform: translateY(-1px);
}

.btn--secondary {
    background-color: #fff;
    color: var(--color-text-primary);
    border: 1px solid var(--color-border);
}

.btn--secondary:hover {
    border-color: var(--color-border-hover);
    background-color: var(--color-background);
}

.btn--sm {
    padding: 6px 12px;
    font-size: 0.875rem;
}

.btn--lg {
    padding: 14px 28px;
    font-size: 1.125rem;
}

.btn--full {
    width: 100%;
}

/* ==========================================================================
   Layout Components
   ========================================================================== */

/* Header */
.site-header {
    background-color: var(--color-header-bg);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    z-index: 100;
}

.site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.site-header__brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--color-text-primary);
}

.site-header__logo {
    max-height: 32px;
}

.site-header__nav {
    display: flex;
    gap: var(--spacing-lg);
    align-items: center;
}

.site-header__link {
    color: var(--color-text-secondary);
    font-weight: 500;
}

.site-header__link:hover {
    color: var(--color-primary);
}

.site-header__hamburger {
    display: none;
    background: none;
    border: none;
    color: var(--color-text-primary);
    cursor: pointer;
    padding: var(--spacing-xs);
}

/* Main */
.site-main {
    flex: 1 0 auto;
}

/* Footer */
.site-footer {
    background-color: var(--color-footer-bg);
    border-top: 1px solid var(--color-border);
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
    margin-top: auto;
}

.site-footer__inner {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-xl);
}

.site-footer__links h4 {
    font-size: 1rem;
    margin-bottom: var(--spacing-md);
}

.site-footer__links nav {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.site-footer__links a {
    color: var(--color-text-secondary);
}

.site-footer__links a:hover {
    color: var(--color-primary);
}

.site-footer__info {
    border-top: 1px solid var(--color-border);
    padding-top: var(--spacing-xl);
    text-align: center;
    color: var(--color-text-secondary);
    font-size: 0.875rem;
}

/* Sections */
.section {
    padding: var(--spacing-3xl) 0;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.section-header__title {
    font-size: 2.5rem;
    margin-bottom: var(--spacing-sm);
}

.section-header__subtitle {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
}

/* ==========================================================================
   Home / Hero
   ========================================================================== */
.hero {
    background-color: var(--color-header-bg);
    border-bottom: 1px solid var(--color-border);
    padding: 80px 0;
    text-align: center;
}

.hero__title {
    font-size: 3.5rem;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: var(--spacing-md);
    background: linear-gradient(135deg, var(--color-text-primary) 0%, var(--color-secondary) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero__subtitle {
    font-size: 1.5rem;
    color: var(--color-text-secondary);
    max-width: 600px;
    margin: 0 auto var(--spacing-2xl);
}

.hero__search {
    max-width: 600px;
    margin: 0 auto;
    position: relative;
    display: flex;
}

.hero__search-input {
    width: 100%;
    padding: 16px 24px;
    font-size: 1.125rem;
    border: 2px solid var(--color-border);
    border-radius: 50px;
    outline: none;
    transition: all var(--transition-base);
    box-shadow: var(--shadow-sm);
}

.hero__search-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 4px rgba(59,91,219,0.1);
}

.hero__search-btn {
    position: absolute;
    right: 8px;
    top: 8px;
    bottom: 8px;
    width: 44px;
    background: var(--color-primary);
    color: #fff;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition-base);
}

.hero__search-btn:hover {
    background: var(--color-primary-dark);
}

/* ==========================================================================
   Tool Grid & Cards
   ========================================================================== */
.tool-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--spacing-lg);
}

.tool-card {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    transition: all var(--transition-base);
    display: flex;
    flex-direction: column;
}

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

.tool-card__image-link {
    display: block;
    aspect-ratio: 16/9;
    overflow: hidden;
    background: var(--color-background);
}

.tool-card__image {
    width: 100%;
    height: 100%;
    position: relative;
}

.tool-card__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.tool-card:hover .tool-card__image img {
    transform: scale(1.05);
}

.tool-card__image-placeholder {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-footer-bg);
}

.tool-card__body {
    padding: var(--spacing-lg);
    flex: 1;
    display: flex;
    flex-direction: column;
}

.tool-card__category {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    font-weight: 700;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.tool-card__title {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-sm);
}

.tool-card__title a {
    color: var(--color-text-primary);
}

.tool-card__title a:hover {
    color: var(--color-primary);
}

.tool-card__desc {
    color: var(--color-text-secondary);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-md);
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.tool-card__tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
    margin-top: auto;
}

.tag-pill {
    font-size: 0.75rem;
    padding: 2px 8px;
    background: var(--color-background);
    border: 1px solid var(--color-border);
    border-radius: 50px;
    color: var(--color-text-secondary);
}

.tool-card__footer {
    padding: var(--spacing-md) var(--spacing-lg);
    border-top: 1px solid var(--color-border);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--color-background);
}

.tool-card__rating {
    display: flex;
    align-items: center;
    gap: 4px;
}

.tool-card__rating-value {
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-primary);
    margin-left: 4px;
}

.empty-state {
    text-align: center;
    padding: var(--spacing-3xl) var(--spacing-lg);
    background: var(--color-card-bg);
    border: 1px dashed var(--color-border);
    border-radius: var(--border-radius-lg);
}

.empty-state svg {
    margin-bottom: var(--spacing-md);
}

.empty-state h3 {
    margin-bottom: var(--spacing-xs);
}

.empty-state p {
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

/* ==========================================================================
   Tool Detail Page
   ========================================================================== */
.tool-detail {
    padding: var(--spacing-2xl) 0;
}

.tool-detail__layout {
    display: grid;
    grid-template-columns: 1fr 350px;
    gap: var(--spacing-2xl);
    align-items: start;
}

.tool-detail__title {
    font-size: 3rem;
    margin-bottom: var(--spacing-md);
}

.tool-summary {
    font-size: 1.25rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-2xl);
}

.tool-detail__content {
    margin-bottom: var(--spacing-3xl);
}

.tool-detail__capabilities {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-3xl);
}

.tool-capabilities {
    list-style: none;
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--spacing-md);
    padding: 0;
}

.tool-capabilities li {
    position: relative;
    padding-left: 24px;
}

.tool-capabilities li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 4px;
    width: 16px;
    height: 16px;
    background-image: url('data:image/svg+xml;utf8,<svg viewBox="0 0 24 24" fill="none" stroke="%233B5BDB" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="20 6 9 17 4 12"></polyline></svg>');
}

/* FAQ Accordion */
.tool-faqs h2 {
    margin-bottom: var(--spacing-lg);
}

.faq-accordion {
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    background: var(--color-card-bg);
}

.faq-item {
    border-bottom: 1px solid var(--color-border);
}

.faq-item:last-child {
    border-bottom: none;
}

.faq-item__question {
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-lg);
    background: none;
    border: none;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--color-text-primary);
    cursor: pointer;
    text-align: left;
}

.faq-item__icon {
    transition: transform var(--transition-base);
}

.faq-item__question[aria-expanded="true"] .faq-item__icon {
    transform: rotate(180deg);
}

.faq-item__answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease-out;
}

.faq-item__answer-text {
    padding: 0 var(--spacing-lg) var(--spacing-lg);
    color: var(--color-text-secondary);
    line-height: 1.6;
}

/* Sidebar */
.tool-sidebar-card {
    background: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    position: sticky;
    top: 90px; /* header height + padding */
}

.tool-sidebar-card__image {
    aspect-ratio: 16/9;
    border-bottom: 1px solid var(--color-border);
}

.tool-sidebar-card__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.tool-sidebar-card__body {
    padding: var(--spacing-xl);
}

.tool-sidebar-card__rating {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-lg);
    border-bottom: 1px solid var(--color-border);
}

.tool-sidebar-card__rating-value {
    font-size: 1.5rem;
    font-weight: 700;
}

.tool-sidebar-card__meta {
    margin-top: var(--spacing-lg);
}

.tool-sidebar-card__label {
    display: block;
    font-size: 0.75rem;
    text-transform: uppercase;
    color: var(--color-text-secondary);
    font-weight: 700;
    margin-bottom: var(--spacing-xs);
}

.tool-sidebar-card__value {
    font-weight: 500;
}

.tool-sidebar-card__tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-xs);
}

/* ==========================================================================
   Static Pages
   ========================================================================== */
.static-page__inner {
    max-width: 800px;
}
.static-page__title {
    font-size: 3rem;
    margin-bottom: var(--spacing-xl);
    text-align: center;
}

/* ==========================================================================
   404 Page
   ========================================================================== */
.error-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 80vh;
    text-align: center;
}
.error-page__content svg {
    margin-bottom: var(--spacing-md);
}
.error-page__content h1 {
    font-size: 4rem;
    margin-bottom: var(--spacing-sm);
}
.error-page__content p {
    color: var(--color-text-secondary);
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xl);
}

/* ==========================================================================
   Pagination
   ========================================================================== */
.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-xs);
    margin-top: var(--spacing-3xl);
}

.pagination__link {
    display: flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-md);
    color: var(--color-text-primary);
    font-weight: 500;
    transition: all var(--transition-base);
    background: var(--color-card-bg);
}

.pagination__link:hover:not(.pagination__link--dots):not(.pagination__link--active) {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.pagination__link--active {
    background: var(--color-primary);
    border-color: var(--color-primary);
    color: #fff;
}

.pagination__link--dots {
    border: none;
    background: transparent;
}

.pagination__link--prev, .pagination__link--next {
    gap: var(--spacing-xs);
}

/* ==========================================================================
   Misc Utilities
   ========================================================================== */
.scroll-top {
    position: fixed;
    bottom: var(--spacing-xl);
    right: var(--spacing-xl);
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--color-primary);
    color: #fff;
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all 0.3s ease;
    box-shadow: var(--shadow-md);
    z-index: 90;
}

.scroll-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.scroll-top:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
}

/* ==========================================================================
   Responsive Breakpoints
   ========================================================================== */
@media (max-width: 992px) {
    .tool-detail__layout {
        grid-template-columns: 1fr;
    }
    .tool-sidebar-card {
        position: static;
    }
}

@media (max-width: 768px) {
    .hero {
        padding: 60px 0;
    }
    .hero__title {
        font-size: 2.5rem;
    }
    .site-header__nav {
        display: none; /* Mobile menu handled by JS */
        position: absolute;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--color-header-bg);
        flex-direction: column;
        padding: var(--spacing-md) var(--spacing-lg);
        border-bottom: 1px solid var(--color-border);
        box-shadow: var(--shadow-sm);
    }
    .site-header__nav.active {
        display: flex;
    }
    .site-header__hamburger {
        display: block;
    }
}