/* Fluent Design System Styles */
/* Based on Microsoft Fluent 2 Design System */

:root {
    /* Fluent Design Colors */
    --fluent-primary: #0078d4;
    --fluent-primary-hover: #106ebe;
    --fluent-primary-pressed: #005a9e;
    --fluent-neutral-background: #ffffff;
    --fluent-neutral-background-hover: #f5f5f5;
    --fluent-neutral-background-pressed: #ebebeb;
    --fluent-neutral-foreground: #242424;
    --fluent-neutral-foreground-secondary: #605e5c;
    --fluent-neutral-stroke: #d1d1d1;
    --fluent-card-background: #ffffff;
    --fluent-card-shadow: 0 2px 4px rgba(0, 0, 0, 0.08), 0 0 2px rgba(0, 0, 0, 0.04);
    --fluent-card-shadow-hover: 0 4px 8px rgba(0, 0, 0, 0.12), 0 0 2px rgba(0, 0, 0, 0.06);
    
    /* Fluent Design Typography - 衬线字体版 */
    --fluent-font-family: 'Noto Serif SC', 'Crimson Text', Georgia, serif;
    --fluent-font-family-sans: 'Segoe UI', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    --fluent-font-size-100: 10px;
    --fluent-font-size-200: 12px;
    --fluent-font-size-300: 14px;
    --fluent-font-size-400: 16px;
    --fluent-font-size-500: 20px;
    --fluent-font-size-600: 24px;
    --fluent-font-size-700: 28px;
    --fluent-font-size-800: 32px;
    --fluent-font-size-900: 40px;
    
    /* Fluent Design Spacing */
    --fluent-spacing-xs: 4px;
    --fluent-spacing-sm: 8px;
    --fluent-spacing-md: 12px;
    --fluent-spacing-lg: 16px;
    --fluent-spacing-xl: 20px;
    --fluent-spacing-xxl: 24px;
    --fluent-spacing-xxxl: 32px;
    
    /* Fluent Design Border Radius */
    --fluent-border-radius-sm: 2px;
    --fluent-border-radius-md: 4px;
    --fluent-border-radius-lg: 8px;
    --fluent-border-radius-xl: 12px;
    
    /* Fluent Design Animation */
    --fluent-duration-fast: 100ms;
    --fluent-duration-normal: 200ms;
    --fluent-duration-slow: 400ms;
    --fluent-curve-easy-ease: cubic-bezier(0.33, 0, 0.67, 1);
    --fluent-curve-accelerate: cubic-bezier(0.9, 0.1, 1, 0.2);
    --fluent-curve-decelerate: cubic-bezier(0.1, 0.9, 0.2, 1);
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --fluent-primary: #4a9eff;
        --fluent-primary-hover: #6cb0ff;
        --fluent-primary-pressed: #2886de;
        --fluent-neutral-background: #1b1b1b;
        --fluent-neutral-background-hover: #2b2b2b;
        --fluent-neutral-background-pressed: #1f1f1f;
        --fluent-neutral-foreground: #ffffff;
        --fluent-neutral-foreground-secondary: #c8c6c4;
        --fluent-neutral-stroke: #414141;
        --fluent-card-background: #292929;
        --fluent-card-shadow: 0 2px 4px rgba(0, 0, 0, 0.24), 0 0 2px rgba(0, 0, 0, 0.12);
        --fluent-card-shadow-hover: 0 4px 8px rgba(0, 0, 0, 0.36), 0 0 2px rgba(0, 0, 0, 0.18);
    }
}

/* Global Fluent Styles */
body {
    font-family: var(--fluent-font-family);
    color: var(--fluent-neutral-foreground);
    background-color: var(--fluent-neutral-background);
    line-height: 1.5;
}

/* Fluent Card Component */
.fluent-card {
    background: var(--fluent-card-background);
    border-radius: var(--fluent-border-radius-lg);
    box-shadow: var(--fluent-card-shadow);
    padding: var(--fluent-spacing-xxl);
    transition: all var(--fluent-duration-normal) var(--fluent-curve-easy-ease);
    border: 1px solid var(--fluent-neutral-stroke);
}

.fluent-card:hover {
    box-shadow: var(--fluent-card-shadow-hover);
    transform: translateY(-2px);
}

.fluent-card-interactive {
    cursor: pointer;
}

.fluent-card-interactive:active {
    transform: translateY(0);
}

/* Fluent Button Component */
.fluent-button {
    font-family: var(--fluent-font-family);
    font-size: var(--fluent-font-size-300);
    font-weight: 600;
    padding: 5px 12px;
    border-radius: var(--fluent-border-radius-md);
    border: 1px solid transparent;
    cursor: pointer;
    transition: all var(--fluent-duration-fast) var(--fluent-curve-easy-ease);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--fluent-spacing-sm);
    text-decoration: none;
    line-height: 1.5;
    min-height: 32px;
}

.fluent-button-primary {
    background: var(--fluent-primary);
    color: #ffffff;
    border-color: var(--fluent-primary);
}

.fluent-button-primary:hover {
    background: var(--fluent-primary-hover);
    border-color: var(--fluent-primary-hover);
}

.fluent-button-primary:active {
    background: var(--fluent-primary-pressed);
    border-color: var(--fluent-primary-pressed);
}

.fluent-button-secondary {
    background: var(--fluent-neutral-background);
    color: var(--fluent-neutral-foreground);
    border-color: var(--fluent-neutral-stroke);
}

.fluent-button-secondary:hover {
    background: var(--fluent-neutral-background-hover);
}

.fluent-button-secondary:active {
    background: var(--fluent-neutral-background-pressed);
}

.fluent-button-subtle {
    background: transparent;
    color: var(--fluent-neutral-foreground);
    border-color: transparent;
}

.fluent-button-subtle:hover {
    background: var(--fluent-neutral-background-hover);
}

.fluent-button-subtle:active {
    background: var(--fluent-neutral-background-pressed);
}

/* Fluent Navigation */
.fluent-nav {
    display: flex;
    align-items: center;
    gap: var(--fluent-spacing-sm);
    padding: var(--fluent-spacing-md) 0;
}

.fluent-nav-link {
    padding: var(--fluent-spacing-sm) var(--fluent-spacing-lg);
    border-radius: var(--fluent-border-radius-md);
    text-decoration: none;
    color: var(--fluent-neutral-foreground);
    font-size: var(--fluent-font-size-300);
    font-weight: 600;
    transition: all var(--fluent-duration-fast) var(--fluent-curve-easy-ease);
    position: relative;
}

.fluent-nav-link:hover {
    background: var(--fluent-neutral-background-hover);
}

.fluent-nav-link.active {
    color: var(--fluent-primary);
}

.fluent-nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: var(--fluent-spacing-lg);
    right: var(--fluent-spacing-lg);
    height: 2px;
    background: var(--fluent-primary);
    border-radius: 2px 2px 0 0;
}

/* Fluent Badge/Tag */
.fluent-badge {
    display: inline-flex;
    align-items: center;
    padding: 2px var(--fluent-spacing-sm);
    border-radius: var(--fluent-border-radius-sm);
    font-size: var(--fluent-font-size-200);
    font-weight: 600;
    background: var(--fluent-neutral-background-hover);
    color: var(--fluent-neutral-foreground-secondary);
    border: 1px solid var(--fluent-neutral-stroke);
}

.fluent-badge-primary {
    background: rgba(0, 120, 212, 0.1);
    color: var(--fluent-primary);
    border-color: var(--fluent-primary);
}

/* Fluent Divider */
.fluent-divider {
    height: 1px;
    background: var(--fluent-neutral-stroke);
    border: none;
    margin: var(--fluent-spacing-xxl) 0;
}

/* Fluent Avatar */
.fluent-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    overflow: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--fluent-neutral-background-hover);
    color: var(--fluent-neutral-foreground);
    font-weight: 600;
    font-size: var(--fluent-font-size-400);
}

.fluent-avatar-large {
    width: 72px;
    height: 72px;
    font-size: var(--fluent-font-size-600);
}

.fluent-avatar-xlarge {
    width: 120px;
    height: 120px;
    font-size: var(--fluent-font-size-800);
}

/* Fluent Text Styles */
.fluent-title-1 {
    font-size: var(--fluent-font-size-900);
    font-weight: 600;
    line-height: 1.25;
    margin: 0;
}

.fluent-title-2 {
    font-size: var(--fluent-font-size-800);
    font-weight: 600;
    line-height: 1.25;
    margin: 0;
}

.fluent-title-3 {
    font-size: var(--fluent-font-size-700);
    font-weight: 600;
    line-height: 1.3;
    margin: 0;
}

.fluent-subtitle-1 {
    font-size: var(--fluent-font-size-500);
    font-weight: 600;
    line-height: 1.4;
    margin: 0;
}

.fluent-subtitle-2 {
    font-size: var(--fluent-font-size-400);
    font-weight: 600;
    line-height: 1.4;
    margin: 0;
}

.fluent-body-1 {
    font-size: var(--fluent-font-size-400);
    font-weight: 400;
    line-height: 1.5;
    margin: 0;
}

.fluent-body-2 {
    font-size: var(--fluent-font-size-300);
    font-weight: 400;
    line-height: 1.5;
    margin: 0;
}

.fluent-caption {
    font-size: var(--fluent-font-size-200);
    font-weight: 400;
    line-height: 1.5;
    color: var(--fluent-neutral-foreground-secondary);
    margin: 0;
}

/* Fluent Link */
.fluent-link {
    color: var(--fluent-primary);
    text-decoration: none;
    transition: color var(--fluent-duration-fast) var(--fluent-curve-easy-ease);
}

.fluent-link:hover {
    color: var(--fluent-primary-hover);
    text-decoration: underline;
}

/* Fluent Acrylic Effect (subtle background blur) */
.fluent-acrylic {
    background: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(30px);
    -webkit-backdrop-filter: blur(30px);
}

@media (prefers-color-scheme: dark) {
    .fluent-acrylic {
        background: rgba(44, 44, 44, 0.7);
    }
}

/* Fluent Reveal Effect (hover highlight) */
.fluent-reveal {
    position: relative;
    overflow: hidden;
}

.fluent-reveal::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(255, 255, 255, 0.1), transparent 50%);
    opacity: 0;
    transition: opacity var(--fluent-duration-fast) var(--fluent-curve-easy-ease);
    pointer-events: none;
}

.fluent-reveal:hover::before {
    opacity: 1;
}

/* Fluent Focus Styles */
*:focus-visible {
    outline: 2px solid var(--fluent-primary);
    outline-offset: 2px;
    border-radius: var(--fluent-border-radius-sm);
}

/* Fluent List */
.fluent-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.fluent-list-item {
    padding: var(--fluent-spacing-md) var(--fluent-spacing-lg);
    border-radius: var(--fluent-border-radius-md);
    transition: background var(--fluent-duration-fast) var(--fluent-curve-easy-ease);
}

.fluent-list-item:hover {
    background: var(--fluent-neutral-background-hover);
}

/* Fluent Grid System */
.fluent-grid {
    display: grid;
    gap: var(--fluent-spacing-xxl);
}

.fluent-grid-2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.fluent-grid-3 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.fluent-grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .fluent-grid-2,
    .fluent-grid-3,
    .fluent-grid-4 {
        grid-template-columns: 1fr;
    }
}

/* Fluent Stack (Flexbox utilities) */
.fluent-stack {
    display: flex;
    flex-direction: column;
    gap: var(--fluent-spacing-lg);
}

.fluent-stack-horizontal {
    flex-direction: row;
    align-items: center;
}

.fluent-stack-wrap {
    flex-wrap: wrap;
}