:root {
    /* Logo-driven Color Palette */
    --primary: #de4e17;
    --primary-dark: #b03e13;
    --primary-light: #ff7f48;
    --accent: #de4e17;
    --accent-2: #ff9a66;

    /* Backgrounds */
    --bg-app: #fafbfc;
    --bg-sidebar: #ffffff;
    --bg-card: #ffffff;
    --bg-hover: #f7f8fa;
    --bg-active: #eef2ff;

    /* Text */
    --text-primary: #1a202c;
    --text-secondary: #4a5568;
    --text-muted: #718096;
    --text-white: #ffffff;
    
    /* Borders */
    --border: #e2e8f0;
    --border-light: #f0f4f8;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.05);
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
    --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.12);
    --shadow-xl: 0 12px 32px rgba(0, 0, 0, 0.15);

    /* Gradient */
    --gradient-primary: linear-gradient(135deg, #de4e17 0%, #b03e13 100%);
    --gradient-accent: linear-gradient(135deg, #ff9a66 0%, #de4e17 100%);
    --gradient-blue: linear-gradient(135deg, #de4e17 0%, #ff7f48 100%);

    /* Spacing */
    --radius: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;

    /* Transition */
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Dark Mode */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-app: #131313; /* main background from logo dark */
        --bg-sidebar: #0f0f0f;
        --bg-card: #181818;
        --bg-hover: #1f1f1f;
        --bg-active: #2a2a2a;

        --text-primary: #ffffff;
        --text-secondary: #d1d1d1;
        --text-muted: #9aa0a0;

        --border: #1b1b1b;
        --border-light: #151515;
    }
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: var(--bg-app);
    color: var(--text-primary);
    line-height: 1.6;
    overflow: hidden;
}

.app-container {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

/* ============ SIDEBAR ============ */
.sidebar {
    width: 280px;
    background: var(--bg-sidebar);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
}

.sidebar-header {
    height: 80px;
    padding: 1.5rem 1.5rem;
    border-bottom: 1px solid var(--border-light);
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--gradient-primary);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}

.logo-icon svg {
    width: 22px;
    height: 22px;
}

.logo h1 {
    font-size: 1.375rem;
    font-weight: 700;
    color: var(--text-primary);
}

.sidebar-nav {
    padding: 1.5rem 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 0.875rem;
    padding: 0.75rem 1rem;
    background: transparent;
    border: none;
    border-radius: var(--radius);
    color: var(--text-secondary);
    font-size: 0.9375rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
}

.nav-item svg {
    width: 20px;
    height: 20px;
}

.nav-item:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.nav-item.active {
    background: var(--bg-active);
    color: var(--primary);
    font-weight: 600;
}

.sidebar-section {
    flex: 1;
    padding: 0 1rem;
    overflow-y: auto;
    margin-top: 0.5rem;
}

.sidebar-section::-webkit-scrollbar {
    width: 4px;
}

.sidebar-section::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 2px;
}

.section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 1rem;
    padding: 0 0.5rem;
}

.sidebar-title {
    font-size: 0.6875rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
}

.feed-sources {
    display: flex;
    flex-direction: column;
    gap: 0.25rem;
}

.feed-button {
    display: flex;
    align-items: center;
    padding: 0.625rem 0.875rem;
    background: transparent;
    border: none;
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.feed-button:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.feed-button.active {
    background: var(--bg-active);
    color: var(--primary);
    font-weight: 600;
}

.sidebar-footer {
    padding: 1.5rem 1.5rem;
    border-top: 1px solid var(--border-light);
}

.footer-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.625rem;
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-hover);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.footer-btn:hover {
    background: var(--bg-card);
    border-color: var(--primary);
    color: var(--primary);
}

.footer-btn svg {
    width: 18px;
    height: 18px;
}

/* ============ MAIN CONTENT ============ */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.top-bar {
    height: 80px;
    background: var(--bg-sidebar);
    border-bottom: 1px solid var(--border);
    padding: 0 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.mobile-menu-btn {
    display: none;
}

.top-bar-title h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.top-bar-title p {
    font-size: 0.875rem;
    color: var(--text-muted);
    margin-top: 0.125rem;
}

.top-bar-actions {
    display: flex;
    gap: 0.5rem;
}

/* ============ BUTTONS ============ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.625rem 1.125rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.9375rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.btn svg {
    width: 18px;
    height: 18px;
}

.btn-primary {
    background: var(--bg-card);
    color: var(--primary);
    border: 2px solid var(--primary);
    box-shadow: var(--shadow);
}

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

.btn-ghost {
    background: transparent;
    color: var(--text-secondary);
}

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

.icon-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    border-radius: 10px;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
}

.icon-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

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

/* ============ VIEWS ============ */
.views-container {
    flex: 1;
    overflow: hidden;
    position: relative;
}

.view {
    display: none;
    height: 100%;
    overflow-y: auto;
    padding: 2rem;
}

.view::-webkit-scrollbar {
    width: 6px;
}

.view::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 3px;
}

.view.active {
    display: block;
}

/* ============ LOADING & EMPTY STATES ============ */
.loading-state {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    height: 100%;
}

.spinner {
    width: 48px;
    height: 48px;
    border: 3px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

.empty-state {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1.5rem;
    text-align: center;
    height: 100%;
}

.empty-state-icon {
    width: 96px;
    height: 96px;
    border-radius: 24px;
    background: var(--bg-active);
    display: flex;
    align-items: center;
    justify-content: center;
}

.empty-state-icon svg {
    width: 48px;
    height: 48px;
    color: var(--primary);
}

.empty-state h2 {
    font-size: 1.5rem;
    font-weight: 700;
}

.empty-state p {
    color: var(--text-muted);
    max-width: 400px;
}

/* ============ ARTICLES GRID ============ */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(360px, 1fr));
    gap: 1.5rem;
}

.article-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.article-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.article-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
}

.article-source {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--primary);
    background: var(--bg-active);
    padding: 0.375rem 0.75rem;
    border-radius: 6px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.bookmark-btn {
    background: transparent;
    border: none;
    color: var(--text-muted);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: 8px;
    transition: var(--transition);
    flex-shrink: 0;
}

.bookmark-btn:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.bookmark-btn.bookmarked {
    color: #f59e0b;
}

.bookmark-btn.bookmarked svg {
    fill: currentColor;
}

.article-title {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-description {
    font-size: 0.9375rem;
    color: var(--text-secondary);
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.article-footer {
    display: flex;
    align-items: center;
    font-size: 0.8125rem;
    color: var(--text-muted);
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-light);
}

/* ============ DISCOVER ============ */
.discover-content {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.discover-categories {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.category-chip {
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 20px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.category-chip:hover {
    background: var(--bg-hover);
    border-color: var(--primary);
    color: var(--primary);
}

.category-chip.active {
    background: var(--gradient-primary);
    border-color: transparent;
    color: white;
}

.discover-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
}

.discover-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
    transition: var(--transition);
}

.discover-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
}

.discover-card-header {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
}

.discover-icon {
    width: 56px;
    height: 56px;
    border-radius: 12px;
    background: var(--gradient-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.5rem;
    font-weight: 700;
    flex-shrink: 0;
}

.discover-info {
    flex: 1;
}

.discover-info h3 {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.discover-info p {
    font-size: 0.875rem;
    color: var(--text-muted);
}

.discover-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 0.8125rem;
    color: var(--text-muted);
}

.discover-tag {
    background: var(--bg-hover);
    padding: 0.25rem 0.625rem;
    border-radius: 6px;
    font-weight: 600;
}

.discover-actions {
    display: flex;
    gap: 0.75rem;
}

.discover-actions .btn {
    flex: 1;
}

/* ============ MODAL ============ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: var(--bg-sidebar);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    width: 90%;
    max-width: 500px;
    box-shadow: var(--shadow-xl);
    animation: modalSlideIn 0.3s ease-out;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 1.5rem 1rem;
}

.modal-header h2 {
    font-size: 1.375rem;
    font-weight: 700;
}

.modal form {
    padding: 0 1.5rem 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.form-group label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-secondary);
}

.form-group label svg {
    width: 16px;
    height: 16px;
}

.form-group input {
    padding: 0.875rem 1rem;
    background: var(--bg-app);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    color: var(--text-primary);
    font-size: 0.9375rem;
    transition: var(--transition);
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

.modal-actions {
    display: flex;
    gap: 0.75rem;
    padding-top: 0.5rem;
}

.modal-actions .btn {
    flex: 1;
}

/* ============ CONTEXT MENU ============ */
.context-menu {
    display: none;
    position: fixed;
    background: var(--bg-sidebar);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    box-shadow: var(--shadow-xl);
    padding: 0.5rem;
    min-width: 200px;
    z-index: 1000;
    animation: contextMenuSlideIn 0.2s ease-out;
}

@keyframes contextMenuSlideIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

.context-menu-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    width: 100%;
    padding: 0.75rem 1rem;
    background: transparent;
    border: none;
    border-radius: 8px;
    color: var(--text-secondary);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-align: left;
}

.context-menu-item:hover {
    background: var(--bg-hover);
    color: var(--text-primary);
}

.context-menu-item.delete:hover {
    background: rgba(239, 68, 68, 0.1);
    color: #ef4444;
}

.context-menu-item svg {
    width: 18px;
    height: 18px;
}

/* ============ RESPONSIVE ============ */
@media (max-width: 1200px) {
    .articles-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
    
    .discover-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    }
}

@media (max-width: 768px) {
    .sidebar {
        position: fixed;
        left: 0;
        top: 0;
        height: 100vh;
        z-index: 100;
        transform: translateX(-100%);
        transition: transform 0.3s ease-out;
        box-shadow: var(--shadow-xl);
    }
    
    .sidebar.mobile-active {
        transform: translateX(0);
    }
    
    .mobile-menu-btn {
        display: flex;
        align-items: center;
        justify-content: center;
        background: transparent;
        border: none;
        color: var(--text-secondary);
        cursor: pointer;
        padding: 0.5rem;
        border-radius: 8px;
    }
    
    .mobile-menu-btn:hover {
        background: var(--bg-hover);
    }
    
    .mobile-menu-btn svg {
        width: 24px;
        height: 24px;
    }
    
    .top-bar {
        height: 70px;
        padding: 0 1rem;
    }
    
    .view {
        padding: 1.5rem 1rem;
    }
    
    .articles-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .discover-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .top-bar {
        height: 70px;
    }
    
    .top-bar-title h1 {
        font-size: 1.25rem;
    }
    
    .view {
        padding: 1rem;
    }
    
    .article-card {
        padding: 1.25rem;
    }
}