/* Custom Palette Colors (Colors Unchanged) */
:root {
    --teal-dark: #177D81;       /* Dark Teal - Main Headers & Accents */
    --teal-light: #BDDED6;      /* Soft Teal - Light Borders & Inputs */
    --accent-yellow: #D98E18;   /* Dark Yellow / Amber */
    --teal-dark-hover: #126367; /* Dark Teal Hover State */
    --teal-subtle: #f0f7f5;     /* Tinted Light Background */
    --footer-link-color: #0d9488; /* Distinct Color for Footer Link */
    
    /* Neutral Theme Variables */
    --bg-main: #ffffff;
    --bg-card: #f8faf9;
    --border-color: #BDDED6;
    --primary: #0f2728;         /* Dark Text */
    --text-main: #0f2728;
    --text-muted: #4e6c6d;
    --sidebar-width: 280px;
    --shadow-sm: 0 10px 25px -5px rgba(23, 125, 129, 0.05), 0 8px 10px -6px rgba(23, 125, 129, 0.05);
    --shadow-md: 0 20px 25px -5px rgba(23, 125, 129, 0.1), 0 8px 10px -6px rgba(23, 125, 129, 0.1);
    --radius: 20px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Plus Jakarta Sans', 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

body {
    background-color: var(--bg-main);
    color: var(--text-main);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Layout Structure */
.app-layout {
    display: flex;
    flex: 1;
    position: relative;
}

/* Sidebar Styling - Redesigned with Floating Glass/Panel Aesthetic */
.sidebar {
    width: var(--sidebar-width);
    background-color: #ffffff;
    border-right: 2px dashed var(--teal-light);
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    z-index: 100;
    transition: transform 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.sidebar.collapsed {
    transform: translateX(-100%);
}

.sidebar-header {
    padding: 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 2px dashed var(--teal-light);
}

.logo-container {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--teal-dark);
    font-weight: 800;
    font-size: 1.2rem;
    letter-spacing: -0.5px;
}

.sidebar-nav {
    padding: 24px 16px;
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 18px;
    color: var(--text-muted);
    text-decoration: none;
    border-radius: 14px;
    font-weight: 600;
    font-size: 0.95rem;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    border: 1px solid transparent;
}

.nav-item:hover, .nav-item.active {
    background-color: var(--teal-subtle);
    color: var(--teal-dark);
    border-color: var(--teal-light);
    transform: translateX(4px);
    box-shadow: var(--shadow-sm);
}

/* Main Content Wrapper */
.main-wrapper {
    flex: 1;
    margin-left: var(--sidebar-width);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: margin-left 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

.main-wrapper.expanded {
    margin-left: 0;
}

/* Header Navbar - Redesigned with Floating Header Effect */
.top-header {
    height: 80px;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    display: grid;
    grid-template-columns: 48px 1fr 48px;
    align-items: center;
    padding: 0 32px;
    position: sticky;
    top: 0;
    z-index: 90;
}

.header-left {
    display: flex;
    align-items: center;
}

.toggle-btn {
    background: var(--teal-subtle);
    border: 2px solid var(--teal-light);
    border-radius: 14px;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--teal-dark);
    font-size: 1.1rem;
    transition: all 0.3s ease;
}

.toggle-btn:hover {
    background-color: var(--teal-dark);
    color: #ffffff;
    border-color: var(--teal-dark);
    transform: rotate(90deg);
}

.header-title {
    text-align: center;
}

.header-title h1 {
    font-size: 1.35rem;
    color: var(--primary);
    font-weight: 800;
    letter-spacing: -0.5px;
}

/* Main Body & Layout */
.content-body {
    padding: 32px;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    flex: 1;
}

.container {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

/* Cards & Layout - Redesigned with Heavy Rounded Corners and Deep Soft Shadows */
.card {
    background: #ffffff;
    border: 2px solid var(--border-color);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow-sm);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.theory-card {
    background: var(--bg-card);
    border-style: dashed;
}

.theory-text {
    font-size: 1rem;
    color: var(--text-muted);
    font-weight: 500;
    line-height: 1.6;
}

.canvas-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    background: #ffffff;
    padding: 24px 20px 32px 20px;
}

canvas {
    width: 100%;
    max-width: 800px;
    height: auto;
    touch-action: none;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.controls-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

@media (min-width: 768px) {
    .controls-grid {
        grid-template-columns: 1fr 1fr;
    }
}

.card-title {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
    border-bottom: 2px solid var(--teal-subtle);
    padding-bottom: 12px;
    letter-spacing: -0.3px;
}

.card-title i {
    color: var(--teal-dark);
    background: var(--teal-subtle);
    padding: 8px;
    border-radius: 10px;
}

.control-group {
    margin-bottom: 20px;
}

.control-group:last-child {
    margin-bottom: 0;
}

.control-group label {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    font-weight: 700;
    color: var(--text-main);
    margin-bottom: 8px;
}

.value-tag {
    color: var(--teal-dark);
    background: var(--teal-subtle);
    border: 1.5px solid var(--teal-light);
    padding: 3px 10px;
    border-radius: 8px;
    font-family: monospace;
    font-weight: 800;
}

input[type="range"] {
    width: 100%;
    height: 8px;
    border-radius: 6px;
    background: var(--teal-subtle);
    border: 1px solid var(--teal-light);
    outline: none;
    accent-color: var(--teal-dark);
    cursor: pointer;
}

/* Input & Select Controls for 6.html - Redesigned Pill/Modern look */
input[type="number"], select {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 1rem;
    color: var(--text-main);
    background-color: var(--bg-card);
    outline: none;
    transition: all 0.3s ease;
}

input[type="number"]:focus, select:focus {
    border-color: var(--teal-dark);
    background-color: #ffffff;
    box-shadow: 0 0 0 4px var(--teal-subtle);
}

.btn {
    width: 100%;
    padding: 14px 20px;
    background-color: var(--teal-dark);
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    box-shadow: 0 4px 14px rgba(23, 125, 129, 0.3);
}

.btn:hover {
    background-color: var(--teal-dark-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(23, 125, 129, 0.4);
}

.btn-secondary {
    background-color: #475569;
    box-shadow: 0 4px 14px rgba(71, 85, 105, 0.3);
}

.btn-secondary:hover {
    background-color: #334155;
    box-shadow: 0 6px 20px rgba(71, 85, 105, 0.4);
}

/* Data Table - Modernized Floating Table Design */
.table-responsive {
    overflow-x: auto;
    border-radius: 12px;
    border: 1px solid var(--border-color);
}

.data-table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    font-size: 0.95rem;
}

.data-table th {
    background-color: var(--teal-subtle);
    color: var(--teal-dark);
    font-weight: 700;
    text-align: left;
    padding: 14px 16px;
    border-bottom: 2px solid var(--teal-light);
    letter-spacing: -0.2px;
}

.data-table td {
    padding: 14px 16px;
    border-bottom: 1px solid var(--border-color);
    color: var(--text-main);
    background-color: #ffffff;
}

.data-table tr:last-child td {
    border-bottom: none;
}

/* Status Indicators - Badge Pill Overhaul */
.status-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 22px;
    border-radius: 30px;
    font-size: 0.9rem;
    font-weight: 700;
    margin-top: 25px;
    box-shadow: var(--shadow-sm);
}

.status-balanced {
    background-color: var(--teal-subtle);
    color: var(--teal-dark);
    border: 2px solid var(--teal-light);
}

.status-unbalanced {
    background-color: #fef2f2;
    color: #991b1b;
    border: 2px solid #fecaca;
}

.equation-box {
    background-color: var(--bg-card);
    border-left: 6px solid var(--teal-dark);
    padding: 16px 20px;
    font-family: 'Plus Jakarta Sans', system-ui, sans-serif;
    font-size: 1rem;
    color: var(--primary);
    margin-top: 20px;
    border-radius: 0 16px 16px 0;
    line-height: 1.6;
    border: 1px solid var(--border-color);
    border-left-width: 6px;
}

.formula {
    font-style: normal;
    background: #ffffff;
    padding: 14px;
    border-radius: 12px;
    border: 2px dashed var(--teal-light);
    margin: 12px 0;
    font-family: 'Courier New', monospace;
    font-weight: 700;
    color: var(--teal-dark);
    text-align: center;
}

/* Footer Styling - Modernized Boxed Footer */
.footer {
    background: #ffffff;
    border-top: 2px dashed var(--teal-light);
    padding: 24px 32px;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
    margin-top: auto;
}

.footer p {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
}

.footer-link {
    color: var(--footer-link-color);
    font-weight: 700;
    text-decoration: none;
    transition: all 0.2s ease;
    border-bottom: 2px solid transparent;
}

.footer-link:hover {
    color: var(--teal-dark-hover);
    border-bottom-color: var(--teal-dark-hover);
}

/* Mobile Responsive Optimization */
@media (max-width: 992px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.mobile-open {
        transform: translateX(0);
        box-shadow: 20px 0 50px rgba(0,0,0,0.15);
    }
    
    .main-wrapper {
        margin-left: 0;
    }

    .overlay {
        display: none;
        position: fixed;
        inset: 0;
        background: rgba(15, 39, 40, 0.6);
        backdrop-filter: blur(4px);
        z-index: 95;
    }

    .overlay.active {
        display: block;
    }
}

@media (max-width: 600px) {
    .content-body {
        padding: 16px;
    }

    .container {
        gap: 16px;
    }

    .card {
        padding: 16px;
        border-radius: 16px;
    }

    .header-title h1 {
        font-size: 1.1rem;
    }

    .card-title {
        font-size: 0.95rem;
        margin-bottom: 12px;
        padding-bottom: 8px;
    }

    .theory-text {
        font-size: 0.875rem;
    }

    .control-group label {
        font-size: 0.825rem;
    }

    .value-tag {
        font-size: 0.8rem;
        padding: 2px 6px;
    }

    .data-table {
        font-size: 0.825rem;
    }

    .data-table th, .data-table td {
        padding: 10px 8px;
    }

    .status-badge {
        font-size: 0.8rem;
        padding: 8px 16px;
        margin-top: 20px;
    }

    .equation-box {
        font-size: 0.85rem;
        padding: 12px 14px;
    }

    .canvas-card {
        padding: 16px 10px 20px 10px;
    }

    canvas {
        height: auto;
        width: 100%;
        display: block;
    }
}

/* Footer Custom Links */
.footer-links-group {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin-bottom: 8px;
}

.footer-custom-link {
    font-weight: 700;
    text-decoration: none;
    transition: transform 0.2s ease, opacity 0.2s ease;
    display: inline-block;
}

.footer-custom-link:hover {
    transform: translateY(-2px);
    opacity: 0.9;
    text-decoration: underline;
}

.footer-learny {
    color: #c084fc; /* Light Purple */
}

.footer-science {
    color: #38bdf8; /* Light Blue */
}

/* Sidebar Menu Scroll Buttons */
.sidebar-nav {
    overflow-y: auto;
    scrollbar-width: thin;
}

.menu-scroll-btn {
    display: none;
    width: 100%;
    background-color: var(--teal-subtle);
    border: 1px solid var(--teal-light);
    color: var(--teal-dark);
    padding: 8px;
    cursor: pointer;
    align-items: center;
    justify-content: center;
    font-size: 0.85rem;
    font-weight: 700;
    transition: background-color 0.2s;
    z-index: 5;
}

.scroll-up-btn {
    border-top: none;
    border-bottom: 1px solid var(--border-color);
    border-radius: 0 0 8px 8px;
}

.scroll-down-btn {
    border-bottom: none;
    border-top: 1px solid var(--border-color);
    border-radius: 8px 8px 0 0;
}

.menu-scroll-btn:hover {
    background-color: var(--teal-light);
}

.nav-item {
    position: relative;
    display: flex;
    align-items: center;
    gap: 12px;
}

.menu-tag {
    margin-left: auto;
    background-color: #fee2e2; /* Light Red Background */
    color: #dc2626;          /* Red Text */
    font-size: 0.7rem;
    font-weight: 800;
    padding: 3px 8px;
    border-radius: 6px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border: 1px solid #fecaca;
}

.nav-item.active .menu-tag,
.nav-item:hover .menu-tag {
    background-color: #dc2626; /* Solid Red on Hover/Active */
    color: #ffffff;            /* White Text on Hover/Active */
    border-color: #dc2626;
}
@keyframes fadeIn {
  from { opacity: 0; transform: scale(0.95); }
  to { opacity: 1; transform: scale(1); }
}
/* ===== Ad Popup Animations ===== */
@keyframes adFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}
@keyframes adSlideUp {
  from { opacity: 0; transform: translateY(30px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
/* Header Right & Language Toggle Button */
.header-right {
    display: flex;
    align-items: center;
    justify-content: flex-end;
}

.lang-toggle-btn {
    background: var(--teal-subtle);
    border: 2px solid var(--teal-light);
    border-radius: 14px;
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--teal-dark);
    font-size: 1.1rem;
    transition: all 0.3s ease;
    text-decoration: none;
}

.lang-toggle-btn:hover {
    background-color: var(--teal-dark);
    color: #ffffff;
    border-color: var(--teal-dark);
    transform: rotate(15deg) scale(1.05);
}