.nav-right-area, .nav-links {
    display: flex;
    align-items: center;
}
.nav-links a {
    text-decoration: none;
    color: var(--text-nav);
    font-size: 14px;
    margin-right: 20px;
    transition: color var(--transition-fast);
}
.nav-links a:hover,
.nav-links a.active { color: var(--color-primary); font-weight: var(--font-weight-semibold); }

.lang-switch {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 14px;
}
.lang-switch a {
    text-decoration: none;
    color: var(--text-lang);
    padding: 2px 6px;
    border-radius: 3px;
    transition: all var(--transition-fast);
}
.lang-switch a.lang-active {
    color: var(--color-primary);
    font-weight: var(--font-weight-bold);
}
.lang-switch a.lang-link:hover {
    color: var(--color-primary);
    background: var(--color-primary-light);
}
.lang-sep {
    color: var(--text-lang-sep);
    font-size: 12px;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    color: var(--text-primary);
    font-size: var(--spacing-lg);
    cursor: pointer;
    padding: var(--spacing-xs) var(--spacing-sm);
    line-height: 1;
    transition: color var(--transition-fast);
}
.nav-toggle:hover { color: var(--color-primary); }

.dark-toggle {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 16px;
    margin-left: 12px;
    transition: all var(--transition-fast);
    line-height: 1;
}
.dark-toggle:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.subtitle-toggle {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 13px;
    cursor: pointer;
    padding: 0 0 6px 0;
    margin-bottom: 4px;
    transition: color var(--transition-fast);
}
.subtitle-toggle:hover { color: var(--color-primary); }

.subtitle-input-group {
    display: flex;
    gap: var(--spacing-sm);
    margin-bottom: 12px;
}
.subtitle-input {
    font-size: 13px;
    padding: var(--spacing-sm) 12px;
}
.subtitle-btn {
    background: var(--color-success);
    color: #fff;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 6px;
    cursor: pointer;
    font-weight: var(--font-weight-semibold);
    font-size: 13px;
    transition: background var(--transition-fast);
    white-space: nowrap;
}
.subtitle-btn:hover { background: var(--color-success-hover); }

.player-controls-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}
.share-section {
    display: flex;
    align-items: center;
    gap: 6px;
}
.share-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: var(--font-weight-semibold);
    cursor: pointer;
    text-decoration: none;
    transition: all var(--transition-fast);
    border: 1px solid var(--border-color);
    background: var(--bg-card);
    color: var(--text-btn);
}
.share-btn:hover { border-color: var(--color-primary); color: var(--color-primary); }
.share-twitter { color: #1da1f2; border-color: #1da1f2; }
.share-twitter:hover { background: #1da1f2; color: #fff; }
.share-reddit { color: #ff4500; border-color: #ff4500; }
.share-reddit:hover { background: #ff4500; color: #fff; }
.share-copy:hover { background: var(--color-primary); color: #fff; border-color: var(--color-primary); }

.tools-bar {
    display: flex;
    align-items: center;
    gap: 6px;
}
.tool-btn {
    display: inline-flex;
    align-items: center;
    gap: 4px;
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: var(--font-weight-semibold);
    cursor: pointer;
    border: 1px solid var(--border-color);
    background: var(--bg-card);
    color: var(--text-btn);
    transition: all var(--transition-fast);
}
.tool-btn:hover { border-color: var(--color-primary); color: var(--color-primary); }
.tool-btn .tool-icon { font-size: 14px; line-height: 1; }
.tool-label { white-space: nowrap; }

#pwa-install-btn {
    display: none;
    background: var(--color-primary);
    color: #fff;
    border-color: var(--color-primary);
}
#pwa-install-btn:hover {
    background: var(--color-primary-hover);
    color: #fff;
}

.video-info-section {
    margin-top: var(--spacing-md);
    border-top: 1px solid var(--border-light);
    padding-top: 12px;
}
.feature-grid {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
}
.feature-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 12px;
    border-radius: var(--radius-full);
    border: 1px solid var(--border-color);
    font-size: 13px;
    color: var(--text-feature);
    transition: border-color var(--transition-fast);
}
.feature-item:hover { border-color: var(--border-feature); }
.f-icon { font-size: 15px; line-height: 1; }

.history-section {
    margin-top: var(--spacing-md);
    border-top: 1px solid var(--border-light);
    padding-top: 12px;
}
.history-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-sm);
}
.history-title {
    margin: 0;
    font-size: var(--spacing-lg);
    color: var(--text-primary);
}
.clear-history-btn {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-clear);
    padding: 4px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    transition: all var(--transition-fast);
}
.clear-history-btn:hover { color: var(--color-danger); border-color: var(--color-danger); }

.history-search {
    margin-bottom: var(--spacing-sm);
}
.history-search-input {
    width: 100%;
    padding: 6px 10px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    font-size: 13px;
    background: var(--bg-input);
    color: var(--text-primary);
    outline: none;
    transition: border-color var(--transition-fast);
    box-sizing: border-box;
}
.history-search-input:focus { border-color: var(--color-primary); }
.history-search-input::placeholder { color: var(--text-muted); }

.history-list { display: flex; flex-direction: column; gap: 6px; }
.history-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-sm) 12px;
    background: var(--bg-history);
    border-radius: 6px;
    border: 1px solid var(--border-light);
    transition: all var(--transition-fast);
}
.history-item:hover { border-color: var(--border-feature); background: var(--bg-history-hover); }
.history-info {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}
.history-url {
    flex: 1;
    font-size: 13px;
    color: var(--text-history);
    cursor: pointer;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    font-family: var(--font-mono);
}
.history-url:hover { color: var(--color-primary); }
.history-time {
    font-size: 11px;
    color: var(--text-muted);
    margin-top: 2px;
}
.history-del-btn {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 18px;
    cursor: pointer;
    padding: 0 4px;
    line-height: 1;
    transition: color var(--transition-fast);
}
.history-del-btn:hover { color: var(--color-danger); }

.info-section {
    margin-bottom: 30px;
    padding: 25px;
    background: var(--bg-card);
    border-radius: 10px;
    border: 1px solid var(--border-color);
    box-shadow: var(--shadow-card);
    transition: background-color var(--transition-slow), box-shadow var(--transition-slow);
    will-change: background-color;
}
.info-section h2 {
    font-size: var(--font-size-xl);
    color: var(--text-primary);
    margin-top: 0;
    display: flex;
    align-items: center;
    border-left: 5px solid var(--color-primary);
    padding-left: 15px;
}
.info-section h3 {
    font-size: 1.1rem;
    color: var(--text-primary);
    margin: 20px 0 10px;
}
.info-section p { color: var(--text-secondary); font-size: 1.05rem; }
.info-section ul, .info-section ol {
    color: var(--text-secondary);
    padding-left: 20px;
}
.info-section li { margin-bottom: var(--spacing-sm); }
.article-content p { margin-bottom: 10px; }

.step-list {
    counter-reset: step;
    list-style: none;
    padding-left: 0;
}
.step-list li {
    counter-increment: step;
    padding: 10px 10px 10px 45px;
    position: relative;
    margin-bottom: var(--spacing-sm);
    background: var(--bg-step);
    border-radius: var(--radius-md);
    border: 1px solid var(--border-light);
}
.step-list li::before {
    content: counter(step);
    position: absolute;
    left: 12px;
    top: 10px;
    width: var(--spacing-lg);
    height: var(--spacing-lg);
    background: var(--color-primary);
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: var(--font-weight-bold);
}

.faq-grid { display: grid; gap: 20px; margin-top: 20px; grid-template-columns: repeat(2, 1fr); }
.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 20px;
    cursor: default;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
    will-change: transform;
}
.faq-item:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-faq);
    border-color: var(--color-primary);
}
.faq-item h3 { margin: 0 0 10px 0; font-size: var(--font-size-lg); color: var(--text-primary); }
.faq-item h3 a { text-decoration: none; color: inherit; }
.faq-item h3 a:hover { text-decoration: underline; }
.faq-item h4 { margin: 0 0 10px 0; font-size: var(--font-size-base); color: var(--text-primary); }
.faq-item p { margin: 0; font-size: 0.95rem; color: var(--text-faq); }
.faq-item code {
    background: var(--border-light);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 0.9em;
    color: var(--color-danger);
}

.faq-accordion {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
.faq-details {
    background: var(--bg-card);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: border-color var(--transition-slow), box-shadow var(--transition-slow);
}
.faq-details:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-faq);
}
.faq-details[open] {
    border-color: var(--color-primary);
}
.faq-summary {
    padding: var(--spacing-md) 20px;
    cursor: pointer;
    font-size: var(--font-size-md);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    user-select: none;
}
.faq-summary::-webkit-details-marker {
    display: none;
}
.faq-summary::marker {
    display: none;
    content: "";
}
.faq-details[open] .faq-summary {
    border-bottom: 1px solid var(--border-light);
}
.faq-answer {
    padding: var(--spacing-md) 20px;
    font-size: 0.95rem;
    color: var(--text-faq);
    line-height: var(--line-height-relaxed);
}
.faq-answer a {
    color: var(--color-primary);
    text-decoration: none;
}
.faq-answer a:hover {
    text-decoration: underline;
}
.faq-answer strong {
    color: var(--text-primary);
}
.faq-answer code {
    background: var(--border-light);
    padding: 2px 6px;
    border-radius: 3px;
    font-size: 0.9em;
    color: var(--color-danger);
}

.toast {
    position: fixed;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--bg-toast);
    color: #fff;
    padding: 12px var(--spacing-lg);
    border-radius: var(--radius-md);
    font-size: 14px;
    z-index: var(--z-toast);
    opacity: 0;
    transition: all var(--transition-normal);
    will-change: transform, opacity;
    pointer-events: none;
    max-width: 90%;
    text-align: center;
    box-shadow: var(--shadow-toast);
}
.toast-show {
    transform: translateX(-50%) translateY(0);
    opacity: 1;
}
.toast-error {
    background: var(--color-danger);
}
.toast-success {
    background: var(--color-success);
}

.code-block {
    background: var(--bg-code);
    color: var(--text-code);
    padding: 15px;
    border-radius: var(--radius-md);
    font-family: var(--font-mono);
    font-size: 14px;
    margin: 15px 0;
    overflow-x: auto;
    line-height: 1.5;
}
.code-block-error {
    color: var(--color-danger);
}
.code-block-sm {
    padding: 12px;
    font-size: 13px;
}

.cookie-banner {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-cookie);
    color: var(--text-cookie);
    z-index: var(--z-cookie);
    padding: 15px 0;
    box-shadow: var(--shadow-cookie);
    transition: background-color var(--transition-slow);
}
.cookie-content {
    max-width: 900px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}
.cookie-content p {
    margin: 0;
    font-size: 14px;
}
.cookie-content a {
    color: var(--color-cookie-link);
    text-decoration: underline;
}
.cookie-buttons {
    display: flex;
    gap: 10px;
    flex-shrink: 0;
}
.cookie-btn {
    padding: var(--spacing-sm) 20px;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: var(--font-weight-semibold);
    transition: background var(--transition-fast);
}
.cookie-accept-btn {
    background: var(--color-primary);
    color: #fff;
}
.cookie-accept-btn:hover { background: var(--color-primary-hover); }
.cookie-reject-btn {
    background: var(--color-cookie-reject);
    color: var(--text-cookie);
}
.cookie-reject-btn:hover { background: var(--color-cookie-reject-hover); }

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--overlay-bg);
    z-index: var(--z-modal);
    display: none;
    align-items: center;
    justify-content: center;
    padding: 20px;
}
.modal-overlay.modal-show {
    display: flex;
}
.modal-box {
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    padding: var(--spacing-lg);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: var(--shadow-modal);
    position: relative;
}
.modal-close {
    position: absolute;
    top: 12px;
    right: 12px;
    background: none;
    border: none;
    font-size: var(--spacing-lg);
    color: var(--text-muted);
    cursor: pointer;
    padding: 4px var(--spacing-sm);
    line-height: 1;
    transition: color var(--transition-fast);
}
.modal-close:hover { color: var(--text-primary); }
.modal-title {
    margin: 0 0 var(--spacing-md) 0;
    font-size: 18px;
    font-weight: var(--font-weight-bold);
    color: var(--text-primary);
}
.modal-embed-code {
    width: 100%;
    min-height: 80px;
    padding: 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-family: var(--font-mono);
    font-size: 12px;
    background: var(--bg-input);
    color: var(--text-primary);
    resize: vertical;
    box-sizing: border-box;
}
.modal-copy-btn {
    margin-top: 12px;
    background: var(--color-primary);
    color: #fff;
    border: none;
    padding: var(--spacing-sm) 20px;
    border-radius: 6px;
    cursor: pointer;
    font-weight: var(--font-weight-semibold);
    font-size: 14px;
    transition: background var(--transition-fast);
}
.modal-copy-btn:hover { background: var(--color-primary-hover); }
.modal-qr-img {
    display: block;
    margin: 0 auto;
    max-width: 200px;
}
.modal-hint {
    text-align: center;
    color: var(--text-secondary);
    font-size: 13px;
    margin-top: 12px;
}

.drag-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--drag-overlay-bg);
    z-index: var(--z-overlay);
    display: none;
    align-items: center;
    justify-content: center;
    pointer-events: none;
}
.drag-overlay.drag-show {
    display: flex;
}
.drag-overlay-content {
    background: var(--bg-card);
    border: 2px dashed var(--color-primary);
    border-radius: var(--radius-xl);
    padding: 40px 60px;
    text-align: center;
    box-shadow: var(--shadow-card);
}
.drag-overlay-icon {
    font-size: 48px;
    margin-bottom: 12px;
}
.drag-overlay-text {
    font-size: 18px;
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
}
.drag-overlay-hint {
    font-size: 14px;
    color: var(--text-secondary);
    margin-top: var(--spacing-sm);
}

.page-footer {
    margin-top: var(--spacing-xl);
    padding-top: 20px;
    border-top: 1px solid var(--border-light);
    text-align: center;
}
.footer-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: var(--spacing-md);
    margin-bottom: 12px;
}
.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: color var(--transition-fast);
}
.footer-links a:hover {
    color: var(--color-primary);
}
.footer-copy {
    color: var(--text-muted);
    font-size: 0.8rem;
    margin: 0;
}

.illustration {
    display: block;
    max-width: 100%;
    height: auto;
    margin: var(--spacing-md) auto;
    border-radius: var(--radius-md);
    text-align: center;
    padding: var(--spacing-md) 0;
}

.shortcuts-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}
.shortcut-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 6px 0;
    border-bottom: 1px solid var(--border-light);
}
.shortcut-item:last-child { border-bottom: none; }
.shortcut-item kbd {
    background: var(--bg-history);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-sm);
    padding: 2px var(--spacing-sm);
    font-family: inherit;
    font-size: 13px;
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
    min-width: 40px;
    text-align: center;
}
.shortcut-item span {
    color: var(--text-secondary);
    font-size: 14px;
}

.comparison-table { width: 100%; border-collapse: collapse; margin: 15px 0; }
.comparison-table th { text-align: left; padding: var(--spacing-sm); }
.comparison-table td { padding: var(--spacing-sm); }
.comparison-table thead tr { border-bottom: 2px solid var(--border-color); }
.comparison-table tbody tr { border-bottom: 1px solid var(--border-color); }

.loading-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.6);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: var(--spacing-sm);
    z-index: 10;
    border-radius: var(--radius-md);
}
.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid rgba(255,255,255,0.3);
    border-top-color: #fff;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}
.spinner--sm { width: 16px; height: 16px; border-width: 2px; }
.spinner--lg { width: 40px; height: 40px; border-width: 4px; }
@keyframes spin {
    to { transform: rotate(360deg); }
}
.loading-text {
    color: #fff;
    font-size: 14px;
}

.skeleton {
    background: linear-gradient(90deg, var(--border-light) 25%, var(--border-color) 50%, var(--border-light) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s ease-in-out infinite;
    border-radius: var(--radius-sm);
}
@keyframes shimmer {
    0% { background-position: 200% 0; }
    100% { background-position: -200% 0; }
}
.skeleton--line {
    height: 14px;
    margin-bottom: 6px;
}
.skeleton--line:last-child {
    width: 70%;
}

.error-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-xl);
    text-align: center;
    gap: var(--spacing-md);
}
.error-state__icon {
    font-size: 48px;
    color: var(--color-danger);
}
.error-state__title {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    color: var(--text-primary);
    margin: 0;
}
.error-state__desc {
    font-size: var(--font-size-sm);
    color: var(--text-secondary);
    max-width: 400px;
    margin: 0;
}
.error-state__actions {
    display: flex;
    gap: var(--spacing-sm);
    margin-top: var(--spacing-xs);
}
.error-state__retry {
    background: var(--color-primary);
    color: #fff;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 6px;
    cursor: pointer;
    font-weight: var(--font-weight-semibold);
    font-size: 14px;
    transition: background var(--transition-fast);
}
.error-state__retry:hover { background: var(--color-primary-hover); }
.error-state__help {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    text-decoration: none;
    transition: all var(--transition-fast);
}
.error-state__help:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
}

.retry-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-direction: column;
    gap: var(--spacing-sm);
    z-index: 10;
    border-radius: var(--radius-md);
}
.retry-overlay__text {
    color: #fff;
    font-size: 14px;
    font-weight: var(--font-weight-semibold);
}

.section-spacer { margin-top: 30px; }
.text-center { text-align: center; }
.text-muted-sm { color: var(--text-muted); font-size: 0.8rem; margin-top: 4px; }
.updated-note { color: var(--text-secondary); font-size: 0.9rem; }

.history-export-btn {
    background: none;
    border: 1px solid var(--border-color);
    color: var(--text-clear);
    padding: 4px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    transition: all var(--transition-fast);
}
.history-export-btn:hover { color: var(--color-primary); border-color: var(--color-primary); }

@media print {
    .navbar, .cookie-banner, .share-section, .history-section, .tools-bar, .dark-toggle { display: none; }
    .content-card { box-shadow: none; }
}

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