/* ==========================================================================
   Design System & Premium CSS Custom Properties
   ========================================================================== */
:root {
    /* Fonts */
    --font-sans: 'Outfit', 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: 'JetBrains Mono', SFMono-Regular, Consolas, "Liberation Mono", Menlo, Courier, monospace;

    /* Transition Speeds */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);

    /* Shadow Systems */
    --shadow-sm: 0 2px 8px -1px rgba(0, 0, 0, 0.08), 0 1px 3px 0 rgba(0, 0, 0, 0.03);
    --shadow-md: 0 4px 20px -2px rgba(0, 0, 0, 0.12), 0 2px 8px -1px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 12px 30px -4px rgba(0, 0, 0, 0.15), 0 4px 12px -2px rgba(0, 0, 0, 0.08);
    --shadow-glow: 0 0 25px rgba(99, 102, 241, 0.15);
}

/* Dark Theme Variables (Default) */
html[data-theme="dark"] {
    --bg-app: #080b11;
    --bg-sidebar: #0f131a;
    --bg-card: #151b26;
    --bg-card-hover: #1c2433;
    --bg-input: #1b2230;
    --bg-input-focus: #212b3d;
    
    --border-color: #222d3f;
    --border-color-hover: #2f3d54;
    
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --text-muted: #6b7280;
    
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: rgba(99, 102, 241, 0.1);
    --primary-gradient: linear-gradient(135deg, #6366f1 0%, #a855f7 100%);
    --primary-glow: rgba(99, 102, 241, 0.35);

    --success: #10b981;
    --success-light: rgba(16, 185, 129, 0.1);
    --danger: #ef4444;
    --danger-light: rgba(239, 68, 68, 0.1);
    --warning: #f59e0b;

    --scrollbar-track: #0f131a;
    --scrollbar-thumb: #222d3f;
}

/* Light Theme Variables */
html[data-theme="light"] {
    --bg-app: #f8fafc;
    --bg-sidebar: #ffffff;
    --bg-card: #ffffff;
    --bg-card-hover: #f1f5f9;
    --bg-input: #f1f5f9;
    --bg-input-focus: #e2e8f0;
    
    --border-color: #e2e8f0;
    --border-color-hover: #cbd5e1;
    
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;
    
    --primary: #4f46e5;
    --primary-hover: #3730a3;
    --primary-light: rgba(79, 70, 229, 0.08);
    --primary-gradient: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
    --primary-glow: rgba(79, 70, 229, 0.2);

    --success: #059669;
    --success-light: rgba(5, 150, 105, 0.08);
    --danger: #dc2626;
    --danger-light: rgba(220, 38, 38, 0.08);
    --warning: #d97706;

    --scrollbar-track: #f1f5f9;
    --scrollbar-thumb: #cbd5e1;
}

/* ==========================================================================
   Basic Layout & Reset
   ========================================================================== */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-app);
    color: var(--text-primary);
    overflow: hidden;
    height: 100vh;
    width: 100vw;
    display: flex;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

.app-container {
    display: flex;
    width: 100%;
    height: 100%;
    position: relative;
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
}
::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--border-color-hover);
}

/* ==========================================================================
   Sidebar Styles
   ========================================================================== */
.sidebar {
    width: 280px;
    background-color: var(--bg-sidebar);
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    transition: background-color var(--transition-normal), border-color var(--transition-normal);
    z-index: 10;
}

.sidebar-header {
    padding: 24px;
    border-bottom: 1px solid var(--border-color);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: var(--primary-gradient);
    color: #ffffff;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    box-shadow: 0 4px 15px var(--primary-glow);
}

.logo-text {
    font-size: 1.25rem;
    font-weight: 700;
    letter-spacing: -0.025em;
    background: linear-gradient(to right, var(--text-primary), var(--text-secondary));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.logo-accent {
    color: var(--primary);
    -webkit-text-fill-color: var(--primary);
}

.sidebar-nav {
    flex-grow: 1;
    padding: 24px 16px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.nav-section {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.nav-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    padding-left: 8px;
}

.nav-list {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.nav-item {
    width: 100%;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 10px;
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 0.925rem;
    font-weight: 500;
    transition: all var(--transition-fast);
    cursor: pointer;
    border: 1px solid transparent;
}

.nav-link:hover {
    color: var(--text-primary);
    background-color: var(--bg-card-hover);
    transform: translateX(2px);
}

.nav-item.active .nav-link {
    color: #ffffff;
    background: var(--primary-gradient);
    box-shadow: 0 4px 12px var(--primary-glow);
}

.nav-item.disabled {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 10px;
    color: var(--text-muted);
    font-size: 0.925rem;
    cursor: not-allowed;
    opacity: 0.6;
}

.badge {
    margin-left: auto;
    background-color: var(--border-color);
    color: var(--text-secondary);
    font-size: 0.7rem;
    font-weight: 600;
    padding: 2px 8px;
    border-radius: 20px;
    text-transform: uppercase;
}

.sidebar-footer {
    padding: 20px 16px;
    border-top: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Theme Toggle Slider */
.theme-toggle-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: var(--bg-card);
    padding: 10px 14px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.theme-label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 8px;
}

.theme-btn {
    width: 44px;
    height: 24px;
    border-radius: 12px;
    background-color: var(--border-color);
    border: none;
    position: relative;
    cursor: pointer;
    transition: background-color var(--transition-normal);
}

.theme-btn-ball {
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background-color: #ffffff;
    position: absolute;
    top: 3px;
    left: 3px;
    transition: transform var(--transition-normal);
    box-shadow: var(--shadow-sm);
}

html[data-theme="light"] .theme-btn {
    background-color: var(--primary);
}

html[data-theme="light"] .theme-btn-ball {
    transform: translateX(20px);
}

.developer-info {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* ==========================================================================
   Main Content Workspace Layout
   ========================================================================== */
.main-content {
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
}

.main-header {
    height: 88px;
    padding: 0 32px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    background-color: var(--bg-sidebar);
    transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.header-title-area h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.header-subtitle {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.status-indicator {
    display: flex;
    align-items: center;
    gap: 8px;
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 6px 14px;
    border-radius: 30px;
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.indicator-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: inline-block;
}

.indicator-dot.online {
    background-color: var(--success);
    box-shadow: 0 0 8px var(--success);
}

/* Viewport Mount */
.calculator-viewport {
    flex-grow: 1;
    padding: 32px;
    overflow-y: auto;
    background-color: var(--bg-app);
    transition: background-color var(--transition-normal);
}

/* ==========================================================================
   Modular Calculator Container Styles (LRC Filter Specific)
   ========================================================================== */
.calculator-grid {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 28px;
    max-width: 1400px;
    margin: 0 auto;
}

@media (max-width: 1100px) {
    .calculator-grid {
        grid-template-columns: 1fr;
    }
}

/* Card components */
.calc-card {
    background-color: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 24px;
    box-shadow: var(--shadow-sm);
    transition: background-color var(--transition-normal), border-color var(--transition-normal), transform var(--transition-fast), box-shadow var(--transition-fast);
}

.calc-card:hover {
    border-color: var(--border-color-hover);
}

.card-title {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 20px;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 12px;
}

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

/* Switcher / Segmented Tabs Control */
.calc-tabs {
    display: flex;
    background-color: var(--bg-input);
    border-radius: 12px;
    padding: 4px;
    margin-bottom: 24px;
    border: 1px solid var(--border-color);
}

.tab-btn {
    flex: 1;
    background: none;
    border: none;
    color: var(--text-secondary);
    padding: 10px 16px;
    border-radius: 8px;
    font-family: var(--font-sans);
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
}

.tab-btn:hover {
    color: var(--text-primary);
}

.tab-btn.active {
    color: var(--text-primary);
    background-color: var(--bg-card);
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

/* Forms & Inputs styling */
.form-group {
    margin-bottom: 20px;
    position: relative;
}

.form-label {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text-secondary);
}

/* Integrated Input Wrapper: Input + Selector */
.input-with-select {
    display: flex;
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
    overflow: hidden;
}

.input-with-select:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
    background-color: var(--bg-input-focus);
}

.input-with-select input[type="number"] {
    flex-grow: 1;
    background: none;
    border: none;
    color: var(--text-primary);
    padding: 12px 16px;
    font-family: var(--font-sans);
    font-size: 1rem;
    outline: none;
    width: 60%;
}

.input-with-select select {
    background-color: var(--border-color);
    border: none;
    color: var(--text-primary);
    padding: 0 16px;
    font-family: var(--font-sans);
    font-size: 0.9rem;
    font-weight: 500;
    outline: none;
    cursor: pointer;
    transition: background-color var(--transition-fast);
    border-left: 1px solid var(--border-color);
}

.input-with-select select:hover {
    background-color: var(--border-color-hover);
}

/* Slider Controls */
.slider-group {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-top: 8px;
}

.slider-group input[type="range"] {
    flex-grow: 1;
    -webkit-appearance: none;
    appearance: none;
    height: 6px;
    border-radius: 3px;
    background: var(--border-color);
    outline: none;
}

.slider-group input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--primary);
    cursor: pointer;
    box-shadow: 0 0 6px var(--primary-glow);
    transition: transform var(--transition-fast);
}

.slider-group input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

/* Results Showcase styling */
.results-card {
    background: linear-gradient(135deg, var(--bg-card) 0%, rgba(99, 102, 241, 0.03) 100%);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 24px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    box-shadow: var(--shadow-glow);
}

.result-main {
    text-align: center;
    padding: 16px 8px;
    background-color: rgba(99, 102, 241, 0.05);
    border-radius: 12px;
    border: 1px dashed rgba(99, 102, 241, 0.2);
}

.result-label {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-muted);
    margin-bottom: 8px;
}

.result-value-wrapper {
    display: flex;
    align-items: baseline;
    justify-content: center;
    gap: 4px;
}

.result-value {
    font-family: var(--font-mono);
    font-size: 2.5rem;
    font-weight: 700;
    color: #ffffff;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* In light mode, let text display without transparent gradient if contrast is low */
html[data-theme="light"] .result-value {
    -webkit-text-fill-color: var(--primary);
}

.result-unit {
    font-family: var(--font-sans);
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--text-secondary);
}

/* Mini grids for secondary results */
.results-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.sub-result-card {
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 10px;
    padding: 14px;
    text-align: center;
}

.sub-result-value {
    font-family: var(--font-mono);
    font-size: 1.15rem;
    font-weight: 600;
    color: var(--text-primary);
}

.sub-result-label {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 4px;
}

/* RLC configuration settings (Series vs Parallel) */
.toggle-group {
    display: flex;
    gap: 8px;
    margin-bottom: 20px;
}

.toggle-btn {
    flex: 1;
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 8px;
    border-radius: 8px;
    font-family: var(--font-sans);
    font-size: 0.8rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.toggle-btn.active {
    background-color: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary);
}

/* ==========================================================================
   Schematic & Chart Visualizations
   ========================================================================== */
.visuals-card {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.schematic-box {
    width: 100%;
    height: 180px;
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    position: relative;
}

.schematic-box svg {
    max-width: 90%;
    max-height: 80%;
}

/* SVG Circuit styling components */
.wire {
    stroke: var(--text-secondary);
    stroke-width: 2.5;
    fill: none;
}
.component-outline {
    stroke: var(--text-primary);
    stroke-width: 2.5;
    fill: var(--bg-input);
}
.node-dot {
    fill: var(--primary);
    stroke: var(--text-primary);
    stroke-width: 1.5;
}
.label-text {
    font-family: var(--font-sans);
    font-size: 14px;
    font-weight: 600;
    fill: var(--text-primary);
}

.chart-box {
    width: 100%;
    height: 200px;
    background-color: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    position: relative;
    padding: 10px;
    overflow: hidden;
}

.chart-box canvas {
    width: 100%;
    height: 100%;
    display: block;
}

/* Empty placeholder modules logic */
.module-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 400px;
    text-align: center;
    color: var(--text-muted);
}

.module-placeholder-icon {
    font-size: 3.5rem;
    margin-bottom: 16px;
    color: var(--border-color-hover);
}

/* Validation banner or alerts styling */
.validation-alert {
    background-color: var(--danger-light);
    border: 1px solid var(--danger);
    color: var(--danger);
    padding: 10px 14px;
    border-radius: 8px;
    font-size: 0.8rem;
    margin-bottom: 16px;
    display: none;
    align-items: center;
    gap: 10px;
}

.validation-alert.show {
    display: flex;
    animation: slideIn var(--transition-fast);
}

@keyframes slideIn {
    from { transform: translateY(-10px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

/* ==========================================================================
   Mobile responsiveness menu toggler
   ========================================================================== */
@media (max-width: 768px) {
    body {
        flex-direction: column;
        overflow-y: auto;
        height: auto;
    }
    .app-container {
        flex-direction: column;
        height: auto;
    }
    .sidebar {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
    }
    .sidebar-nav {
        max-height: 200px;
    }
    .main-content {
        height: auto;
        flex-grow: 1;
    }
    .main-header {
        height: auto;
        padding: 20px 24px;
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }
    .calculator-viewport {
        padding: 20px;
    }
}