style.css

/* Base Styles */
:root {
    --primary: #3B82F6;
    --primary-hover: #2563EB;
    --secondary: #10B981;
    --secondary-hover: #059669;
    --bg-dark: #0F172A;
    --bg-darker: #0B1120;
    --bg-panel: #1E293B;
    --bg-panel-dark: #1E293B;
    --text-light: #F8FAFC;
    --text-muted: #94A3B8;
    --text-disabled: #64748B;
    --border: #334155;
    --border-light: #475569;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
}

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    line-height: 1.5;
    overflow: hidden;
}

/* Layout */
.app-container {
    display: grid;
    grid-template-columns: 300px 1fr 400px;
    height: 100vh;
    gap: 16px;
    padding: 16px;
    background: var(--bg-darker);
}

/* Sidebar Styles */
.sidebar {
    background: var(--bg-panel-dark);
    border-radius: var(--radius);
    padding: 16px;
    display: flex;
    flex-direction: column;
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
}

.sidebar-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 8px 0 16px;
    border-bottom: 1px solid var(--border);
    margin-bottom: 16px;
}

.brand-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: linear-gradient(135deg, #3B82F6, #10B981);
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15);
}

.brand-title {
    font-weight: 600;
    font-size: 16px;
}

.search-container {
    display: flex;
    gap: 12px;
    margin-bottom: 16px;
    background: rgba(0, 0, 0, 0.2);
    padding: 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
}

.search-icon {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    color: var(--text-muted);
}

.search-input {
    flex: 1;
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 0 12px;
    color: var(--text-muted);
}

.search-input input {
    width: 100%;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-light);
    padding: 8px 0;
}

.search-input input::placeholder {
    color: var(--text-muted);
}

.navigation {
    flex: 1;
    overflow-y: auto;
    margin-bottom: 16px;
}

.nav-section {
    color: var(--text-muted);
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 12px 8px 4px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    margin-bottom: 4px;
    border: 1px solid transparent;
}

.nav-item:hover {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--border-light);
}

.nav-item.active {
    background: rgba(59, 130, 246, 0.15);
    border-color: rgba(59, 130, 246, 0.3);
}

.nav-icon {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    color: var(--text-muted);
}
.nav-label {
    flex: 1;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-light);
}

.nav-label a {
    color: inherit;
    text-decoration: none;
    display: block;
    width: 100%;
}
.sidebar-footer {
    display: flex;
    justify-content: space-between;
    gap: 8px;
    padding-top: 16px;
    border-top: 1px solid var(--border);
    margin-top: auto;
}

.action-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    padding: 8px 12px;
    border-radius: var(--radius-sm);
    color: var(--text-muted);
    font-size: 14px;
    cursor: pointer;
}

.action-btn:hover {
    background: rgba(255, 255, 255, 0.08);
}

.action-btn small {
    font-size: 12px;
    color: var(--text-disabled);
}

/* Main Content Styles */
.main-content {
    background: linear-gradient(rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.1));
    border-radius: var(--radius);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
    position: relative;
}

.content-header {
    display: flex;
    gap: 8px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.2);
}

.tag {
    padding: 6px 10px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    color: var(--text-muted);
    font-size: 12px;
}

.empty-state {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-muted);
    padding: 24px;
}

.empty-state h3 {
    color: var(--text-light);
    font-weight: 600;
    margin-bottom: 8px;
}

.input-bar {
    margin-top: auto;
    padding: 12px;
    background: rgba(0, 0, 0, 0.25);
    border-top: 1px solid var(--border);
}

.input-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px;
    border-radius: var(--radius);
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
}

.input-btn {
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    color: var(--text-muted);
    cursor: pointer;
}

.input-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-light);
}

.text-input {
    flex: 1;
}

.text-input input {
    width: 100%;
    background: transparent;
    border: none;
    outline: none;
    color: var(--text-light);
    padding: 10px 0;
}

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

.send-btn {
    width: 42px;
    height: 42px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    border-radius: var(--radius-sm);
    border: none;
    color: white;
    cursor: pointer;
}

.send-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.send-btn:hover:not(:disabled) {
    background: var(--primary-hover);
}

/* Preview Panel Styles */
.preview-panel {
    background: var(--bg-panel-dark);
    border-radius: var(--radius);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    display: flex;
    flex-direction: column;
}

.preview-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.2);
}

.preview-header h2 {
    font-size: 16px;
    font-weight: 600;
}

.toolbar {
    display: flex;
    gap: 8px;
}

.tool-btn {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    color: var(--text-muted);
    cursor: pointer;
}

.tool-btn:hover {
    background: rgba(255, 255, 255, 0.08);
    color: var(--text-light);
}

.tool-btn.edit {
    width: auto;
    padding: 0 12px;
    gap: 6px;
}

.preview-content {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    background: rgba(0, 0, 0, 0.25);
}

.preview-error {
    text-align: center;
    max-width: 360px;
    padding: 24px;
}

.error-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: rgba(239, 68, 68, 0.15);
    color: #EF4444;
}

.preview-error h3 {
    font-weight: 600;
    margin-bottom: 8px;
}

.preview-error p {
    color: var(--text-muted);
}

.preview-footer {
    display: flex;
    justify-content: space-between;
    padding: 12px 16px;
    border-top: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.35);
    font-size: 13px;
    color: var(--text-muted);
}

.preview-footer strong {
    color: var(--text-light);
}

/* Responsive Design */
@media (max-width: 1200px) {
    .app-container {
        grid-template-columns: 280px 1fr 360px;
    }
}

@media (max-width: 992px) {
    body {
        overflow: auto;
    }
    
    .app-container {
        grid-template-columns: 1fr;
        height: auto;
    }
    
    .sidebar, .preview-panel {
        min-height: 400px;
    }
}

/* Feather Icons Size */
.feather {
    width: 16px;
    height: 16px;
}