/**
 * 组件样式 - Components
 * 可复用的UI组件
 */

/* ==========================================
   Container
   ========================================== */

.container {
    width: 100%;
    max-width: var(--container-xl);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--space-4);
    padding-right: var(--space-4);
}

.container-sm {
    max-width: var(--container-sm);
}

.container-md {
    max-width: var(--container-md);
}

.container-lg {
    max-width: var(--container-lg);
}

.container-content {
    max-width: var(--content-width);
}

/* ==========================================
   Buttons
   ========================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-3) var(--space-6);
    font-family: var(--font-heading);
    font-size: var(--text-base);
    font-weight: var(--font-medium);
    line-height: 1.5;
    text-decoration: none;
    border: 2px solid transparent;
    border-radius: var(--radius-xl);
    cursor: pointer;
    transition: all var(--transition-base);
    white-space: nowrap;
}

.btn:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Primary Button */
.btn-primary {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background-color: var(--color-primary-hover);
    border-color: var(--color-primary-hover);
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-primary);
    transform: translateY(-1px);
}

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

/* Secondary Button */
.btn-secondary {
    background-color: transparent;
    color: var(--color-text);
    border-color: var(--color-bg-muted);
}

.btn-secondary:hover {
    background-color: var(--color-bg-subtle);
    border-color: var(--color-text-muted);
    color: var(--color-text);
}

/* Outline Button */
.btn-outline {
    background-color: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-outline:hover {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
}

/* Accent Button */
.btn-accent {
    background-color: var(--color-accent);
    color: var(--color-text-inverse);
    border-color: var(--color-accent);
}

.btn-accent:hover {
    background-color: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
    color: var(--color-text-inverse);
    box-shadow: var(--shadow-accent);
}

/* Ghost Button */
.btn-ghost {
    background-color: transparent;
    color: var(--color-text-secondary);
    border-color: transparent;
}

.btn-ghost:hover {
    background-color: var(--color-bg-subtle);
    color: var(--color-text);
}

/* Button Sizes */
.btn-sm {
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    border-radius: var(--radius-lg);
}

.btn-lg {
    padding: var(--space-4) var(--space-8);
    font-size: var(--text-lg);
}

/* Full Width Button */
.btn-full {
    width: 100%;
}

/* Icon Button */
.btn-icon {
    padding: var(--space-3);
    border-radius: var(--radius-lg);
}

.btn-icon svg {
    width: 20px;
    height: 20px;
}

/* ==========================================
   Cards
   ========================================== */

.card {
    background-color: var(--color-bg-subtle);
    border-radius: var(--radius-xl);
    overflow: hidden;
    transition: all var(--transition-slow);
}

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

.card-image {
    width: 100%;
    aspect-ratio: 16 / 10;
    object-fit: cover;
}

.card-body {
    padding: var(--space-6);
}

.card-title {
    font-family: var(--font-heading);
    font-size: var(--text-xl);
    font-weight: var(--font-semibold);
    margin-bottom: var(--space-2);
    color: var(--color-text);
}

.card-title a {
    color: inherit;
}

.card-title a:hover {
    color: var(--color-primary);
}

.card-description {
    color: var(--color-text-secondary);
    font-size: var(--text-base);
    line-height: var(--leading-relaxed);
    margin-bottom: var(--space-4);
}

.card-meta {
    display: flex;
    align-items: center;
    gap: var(--space-4);
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

.card-footer {
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--color-bg-muted);
    background-color: var(--color-bg);
}

/* Card Variants */
.card-flat {
    background-color: var(--color-bg);
    border: 1px solid var(--color-bg-muted);
}

.card-flat:hover {
    border-color: var(--color-primary-light);
}

.card-highlight {
    border: 2px solid var(--color-primary);
}

/* ==========================================
   Tags & Badges
   ========================================== */

.tag {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-family: var(--font-heading);
    font-size: var(--text-xs);
    font-weight: var(--font-medium);
    background-color: var(--color-bg-muted);
    color: var(--color-text-secondary);
    border-radius: var(--radius-full);
    transition: all var(--transition-fast);
}

.tag:hover {
    background-color: var(--color-primary-light);
    color: var(--color-primary);
}

.tag-primary {
    background-color: var(--color-primary-light);
    color: var(--color-primary);
}

.tag-accent {
    background-color: var(--color-accent-light);
    color: var(--color-accent);
}

.tag-success {
    background-color: var(--color-success-light);
    color: var(--color-success);
}

.badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 20px;
    height: 20px;
    padding: 0 var(--space-2);
    font-size: var(--text-xs);
    font-weight: var(--font-semibold);
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
    border-radius: var(--radius-full);
}

/* ==========================================
   Form Elements
   ========================================== */

.form-group {
    margin-bottom: var(--space-6);
}

.form-label {
    display: block;
    font-family: var(--font-heading);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--color-text);
    margin-bottom: var(--space-2);
}

.form-input,
.form-textarea,
.form-select {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    font-family: inherit;
    font-size: var(--text-base);
    color: var(--color-text);
    background-color: var(--color-bg);
    border: 2px solid var(--color-bg-muted);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
}

.form-input:hover,
.form-textarea:hover,
.form-select:hover {
    border-color: var(--color-text-muted);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-input::placeholder,
.form-textarea::placeholder {
    color: var(--color-text-muted);
}

.form-textarea {
    min-height: 120px;
    resize: vertical;
}

.form-hint {
    margin-top: var(--space-2);
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

.form-error {
    margin-top: var(--space-2);
    font-size: var(--text-sm);
    color: var(--color-error);
}

.form-input-error {
    border-color: var(--color-error);
}

.form-input-error:focus {
    box-shadow: 0 0 0 3px var(--color-error-light);
}

/* Input with icon */
.input-group {
    position: relative;
}

.input-group .form-input {
    padding-left: var(--space-10);
}

.input-icon {
    position: absolute;
    left: var(--space-4);
    top: 50%;
    transform: translateY(-50%);
    color: var(--color-text-muted);
}

/* ==========================================
   Avatar
   ========================================== */

.avatar {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    overflow: hidden;
    background-color: var(--color-bg-muted);
}

.avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.avatar-sm {
    width: 32px;
    height: 32px;
}

.avatar-lg {
    width: 64px;
    height: 64px;
}

.avatar-xl {
    width: 96px;
    height: 96px;
}

.avatar-2xl {
    width: 128px;
    height: 128px;
}

/* ==========================================
   Section Headings
   ========================================== */

.section-header {
    text-align: center;
    margin-bottom: var(--space-12);
}

.section-title {
    font-size: var(--text-3xl);
    margin-bottom: var(--space-4);
}

.section-subtitle {
    font-size: var(--text-lg);
    color: var(--color-text-secondary);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Section with left border accent */
.section-title-accented {
    padding-left: var(--space-4);
    border-left: 4px solid var(--color-primary);
}

/* ==========================================
   Dividers
   ========================================== */

.divider {
    height: 1px;
    background-color: var(--color-bg-muted);
    margin: var(--space-8) 0;
}

.divider-vertical {
    width: 1px;
    height: 100%;
    background-color: var(--color-bg-muted);
}

/* ==========================================
   Feature Icons
   ========================================== */

.feature-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: var(--radius-xl);
    background-color: var(--color-primary-light);
    color: var(--color-primary);
    margin-bottom: var(--space-4);
}

.feature-icon svg,
.feature-icon i {
    width: 28px;
    height: 28px;
    font-size: 28px;
}

.feature-icon-accent {
    background-color: var(--color-accent-light);
    color: var(--color-accent);
}

/* ==========================================
   Alerts
   ========================================== */

.alert {
    padding: var(--space-4) var(--space-5);
    border-radius: var(--radius-lg);
    margin-bottom: var(--space-4);
}

.alert-info {
    background-color: var(--color-info-light);
    color: var(--color-info);
}

.alert-success {
    background-color: var(--color-success-light);
    color: var(--color-success);
}

.alert-warning {
    background-color: var(--color-warning-light);
    color: var(--color-text);
}

.alert-error {
    background-color: var(--color-error-light);
    color: var(--color-error);
}

/* ==========================================
   Navigation
   ========================================== */

.nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
}

.nav-link {
    padding: var(--space-2) var(--space-4);
    font-family: var(--font-heading);
    font-size: var(--text-base);
    font-weight: var(--font-medium);
    color: var(--color-text-secondary);
    border-radius: var(--radius-lg);
    transition: all var(--transition-base);
}

.nav-link:hover {
    color: var(--color-text);
    background-color: var(--color-bg-subtle);
}

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

/* Theme Toggle */
.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    font-family: var(--font-heading);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--color-text);
    background-color: var(--color-bg-subtle);
    border: 1px solid var(--color-bg-muted);
    border-radius: var(--radius-full);
    cursor: pointer;
    box-shadow: var(--shadow-xs);
    flex-shrink: 0;
}

.theme-toggle:hover {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
    border-color: var(--color-primary);
}

.theme-toggle:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 3px;
}

.theme-toggle-icon {
    position: relative;
    width: 18px;
    height: 18px;
    flex-shrink: 0;
}

.theme-icon {
    position: absolute;
    inset: 0;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
}

:root[data-theme="light"] .theme-icon-sun,
:root:not([data-theme]) .theme-icon-sun {
    opacity: 0;
    transform: scale(0.85) rotate(-18deg);
}

:root[data-theme="light"] .theme-icon-moon,
:root:not([data-theme]) .theme-icon-moon {
    opacity: 1;
    transform: scale(1) rotate(0deg);
}

:root[data-theme="dark"] .theme-icon-sun {
    opacity: 1;
    transform: scale(1) rotate(0deg);
}

:root[data-theme="dark"] .theme-icon-moon {
    opacity: 0;
    transform: scale(0.85) rotate(18deg);
}

.theme-toggle-label {
    line-height: 1;
}

/* ==========================================
   Dropdown
   ========================================== */

.dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 200px;
    padding: var(--space-2);
    background-color: var(--color-bg-elevated);
    border: 1px solid var(--color-bg-muted);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-8px);
    transition: all var(--transition-base);
    z-index: var(--z-dropdown);
}

.dropdown:hover .dropdown-menu,
.dropdown.open .dropdown-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.dropdown-item {
    display: block;
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    color: var(--color-text);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.dropdown-item:hover {
    background-color: var(--color-bg-subtle);
    color: var(--color-primary);
}

.dropdown-item.active {
    background-color: var(--color-primary-light);
    color: var(--color-primary);
}

.dropdown-divider {
    height: 1px;
    background-color: var(--color-bg-muted);
    margin: var(--space-2) 0;
}

/* ==========================================
   Modal
   ========================================== */

.modal-backdrop {
    position: fixed;
    inset: 0;
    background-color: var(--color-overlay);
    z-index: var(--z-modal-backdrop);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
}

.modal-backdrop.open {
    opacity: 1;
    visibility: visible;
}

.modal {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.95);
    width: 90%;
    max-width: 500px;
    max-height: 90vh;
    background-color: var(--color-bg);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-xl);
    z-index: var(--z-modal);
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-base);
    overflow: hidden;
}

.modal.open {
    opacity: 1;
    visibility: visible;
    transform: translate(-50%, -50%) scale(1);
}

.modal-header {
    padding: var(--space-6);
    border-bottom: 1px solid var(--color-bg-muted);
}

.modal-title {
    font-size: var(--text-xl);
    margin-bottom: 0;
}

.modal-body {
    padding: var(--space-6);
    overflow-y: auto;
}

.modal-footer {
    padding: var(--space-4) var(--space-6);
    border-top: 1px solid var(--color-bg-muted);
    display: flex;
    justify-content: flex-end;
    gap: var(--space-3);
}

/* ==========================================
   Loading Spinner
   ========================================== */

.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--color-bg-muted);
    border-top-color: var(--color-primary);
    border-radius: var(--radius-full);
    animation: spin 0.8s linear infinite;
}

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

/* ==========================================
   Skeleton Loading
   ========================================== */

.skeleton {
    background: linear-gradient(
        90deg,
        var(--color-bg-muted) 25%,
        var(--color-bg-subtle) 50%,
        var(--color-bg-muted) 75%
    );
    background-size: 200% 100%;
    animation: skeleton-loading 1.5s ease-in-out infinite;
    border-radius: var(--radius-md);
}

@keyframes skeleton-loading {
    0% {
        background-position: 200% 0;
    }
    100% {
        background-position: -200% 0;
    }
}

.skeleton-text {
    height: 1em;
    margin-bottom: var(--space-2);
}

.skeleton-title {
    height: 1.5em;
    width: 60%;
    margin-bottom: var(--space-4);
}

.skeleton-avatar {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
}

/* ==========================================
   Empty State
   ========================================== */

.empty-state {
    text-align: center;
    padding: var(--space-16) var(--space-8);
}

.empty-state-icon {
    font-size: 64px;
    color: var(--color-text-muted);
    margin-bottom: var(--space-4);
}

.empty-state-title {
    font-size: var(--text-xl);
    margin-bottom: var(--space-2);
}

.empty-state-description {
    color: var(--color-text-secondary);
    margin-bottom: var(--space-6);
}

/* ==========================================
   Tooltip
   ========================================== */

.tooltip {
    position: relative;
}

.tooltip::after {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    padding: var(--space-2) var(--space-3);
    font-size: var(--text-xs);
    color: var(--color-text-inverse);
    background-color: var(--color-text);
    border-radius: var(--radius-md);
    white-space: nowrap;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-fast);
    z-index: var(--z-tooltip);
}

.tooltip:hover::after {
    opacity: 1;
    visibility: visible;
    transform: translateX(-50%) translateY(-4px);
}

/* ==========================================
   Progress Bar
   ========================================== */

.progress {
    height: 8px;
    background-color: var(--color-bg-muted);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--color-primary);
    border-radius: var(--radius-full);
    transition: width var(--transition-slow);
}

.progress-bar-success {
    background-color: var(--color-success);
}

/* ==========================================
   List Group
   ========================================== */

.list-group {
    border: 1px solid var(--color-bg-muted);
    border-radius: var(--radius-lg);
    overflow: hidden;
}

.list-group-item {
    padding: var(--space-4);
    border-bottom: 1px solid var(--color-bg-muted);
    transition: background-color var(--transition-fast);
}

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

.list-group-item:hover {
    background-color: var(--color-bg-subtle);
}

.list-group-item.active {
    background-color: var(--color-primary-light);
}

/* ==========================================
   Breadcrumb
   ========================================== */

.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--color-text-muted);
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.breadcrumb-item::after {
    content: '/';
    color: var(--color-text-muted);
}

.breadcrumb-item:last-child::after {
    content: none;
}

.breadcrumb-item a {
    color: var(--color-text-secondary);
}

.breadcrumb-item a:hover {
    color: var(--color-primary);
}

.breadcrumb-item.active {
    color: var(--color-text);
}

/* ==========================================
   Pagination
   ========================================== */

.pagination {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.page-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 var(--space-3);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    color: var(--color-text-secondary);
    background-color: var(--color-bg);
    border: 1px solid var(--color-bg-muted);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.page-link:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
    background-color: var(--color-primary-light);
}

.page-link.active {
    color: var(--color-text-inverse);
    background-color: var(--color-primary);
    border-color: var(--color-primary);
}

.page-link.disabled {
    color: var(--color-text-muted);
    cursor: not-allowed;
    opacity: 0.5;
}

/* ==========================================
   User Avatar
   ========================================== */

.user-avatar {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    object-fit: cover;
    border: 2px solid var(--color-border);
}

.user-menu {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.dropdown-menu-right {
    right: 0;
    left: auto;
}