:root {
    /* Fonts & Core */
    --font-family: 'Outfit', sans-serif;
    --transition-speed: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    
    /* Variables for Dark Theme (Default) */
    --bg-color: #090A0F;
    --text-color: #E0E0E0;
    --heading-color: #FFFFFF;
    --card-bg: rgba(20, 20, 30, 0.5);
    --card-border: rgba(255, 255, 255, 0.1);
    --primary-glow: #00F0FF;
    --primary-glow-alpha: rgba(0, 240, 255, 0.4);
    --secondary-glow: #B026FF;
    --accent-color: #00F0FF;
    --locked-bg: rgba(255, 255, 255, 0.05);
    --locked-border: rgba(255, 255, 255, 0.05);
    --locked-filter: grayscale(100%) opacity(50%);
    --card-shadow: 0 8px 32px rgba(0, 240, 255, 0.1);
    
    /* Progress */
    --progress-bg: rgba(255, 255, 255, 0.1);
    --progress-fill: linear-gradient(90deg, var(--secondary-glow), var(--primary-glow));
    
    /* Layout */
    --padding-x: 2rem;
}

[data-theme="light"] {
    --bg-color: #FDFDFD;
    --text-color: #1A1A24;
    --heading-color: #111111;
    --card-bg: rgba(255, 255, 255, 0.7);
    --card-border: rgba(0, 0, 0, 0.1);
    --primary-glow: #2B60DE;
    --primary-glow-alpha: rgba(43, 96, 222, 0.4);
    --secondary-glow: #4169E1;
    --accent-color: #4169E1;
    --locked-bg: rgba(0, 0, 0, 0.05);
    --locked-border: rgba(0, 0, 0, 0.05);
    --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
    
    --progress-bg: rgba(0, 0, 0, 0.1);
    --progress-fill: linear-gradient(90deg, var(--primary-glow), var(--secondary-glow));
}

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

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    overflow-x: hidden;
    min-height: 100vh;
}

/* Common Classes */
.hidden {
    display: none !important;
}

.highlight {
    color: var(--accent-color);
    text-shadow: 0 0 10px var(--primary-glow-alpha);
    transition: color var(--transition-speed), text-shadow var(--transition-speed);
}

.glass-card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    transition: all var(--transition-speed);
}

.btn-glow {
    background: transparent;
    color: var(--heading-color);
    border: 1px solid var(--accent-color);
    padding: 0.8rem 2rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    box-shadow: 0 0 15px var(--primary-glow-alpha);
    transition: all var(--transition-speed);
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.btn-glow::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: var(--accent-color);
    z-index: -1;
    transform: scaleX(0);
    transform-origin: left;
    transition: transform var(--transition-speed);
}

.btn-glow:hover {
    color: #fff;
    box-shadow: 0 0 25px var(--accent-color);
    transform: translateY(-2px);
}

.btn-glow:hover::before {
    transform: scaleX(1);
    color: #fff;
}

.btn-glow:disabled {
    cursor: not-allowed;
    opacity: 0.5;
    border-color: #888;
    box-shadow: none;
    color: #888;
}

.btn-glow:disabled:hover::before {
    transform: scaleX(0);
}

.btn-glow:disabled:hover {
    transform: none;
    color: #888;
}

/* Theme Toggle */
.theme-toggle {
    position: fixed;
    top: 1.5rem;
    right: 1.5rem;
    z-index: 1000;
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    color: var(--text-color);
    width: 45px;
    height: 45px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    transition: all var(--transition-speed);
}

.theme-toggle:hover {
    transform: scale(1.1);
}

.theme-toggle svg {
    width: 20px;
    height: 20px;
    transition: transform var(--transition-speed), opacity var(--transition-speed);
}

[data-theme="dark"] .sun-icon {
    display: none;
}
[data-theme="light"] .moon-icon {
    display: none;
}

/* Splash Screen */
.splash-screen {
    position: fixed;
    top: 0; left: 0;
    width: 100%; height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 100;
    
    /* New Highly Attractive Dynamic Background */
    background: linear-gradient(-45deg, var(--bg-color), #1a0b2e, #0f2027, #112233);
    background-size: 300% 300%;
    animation: gradientBG 12s ease infinite;
    
    transition: opacity 0.8s ease-in-out, visibility 0.8s ease-in-out;
}

@keyframes gradientBG {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

.splash-content {
    z-index: 2;
    text-align: center;
    transform: translateY(40px) scale(0.95);
    opacity: 0;
    animation: floatUpSplash 1.2s cubic-bezier(0.16, 1, 0.3, 1) forwards 0.3s;
}

@keyframes floatUpSplash {
    to { opacity: 1; transform: translateY(0) scale(1); }
}

.greeting {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 2rem;
    opacity: 0;
    transform: scale(0.8);
    animation: fadeScaleIn 1.5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

/* Background floating atoms */
.atoms-background {
    position: absolute;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: 1;
    pointer-events: none;
}

.atom-bubble {
    position: absolute;
    bottom: -100px;
    background: radial-gradient(circle at 30% 30%, var(--primary-glow-alpha), transparent);
    border: 1px solid var(--primary-glow-alpha);
    border-radius: 50%;
    opacity: 0.3;
    animation: floatUp infinite linear;
}

@keyframes floatUp {
    0% { transform: translateY(0) rotate(0deg) scale(1); opacity: 0; }
    10% { opacity: 0.6; box-shadow: 0 0 20px var(--primary-glow-alpha); }
    90% { opacity: 0.2; }
    100% { transform: translateY(-120vh) rotate(360deg) scale(1.5); opacity: 0; }
}

@keyframes fadeScaleIn {
    to { opacity: 1; transform: scale(1); }
}

/* Mega Pulse specifically for Splash Button */
.enter-btn-mega {
    animation: megaPulse 2s infinite;
}

@keyframes megaPulse {
    0% { box-shadow: 0 0 0 0 rgba(0, 240, 255, 0.6); }
    70% { box-shadow: 0 0 0 25px rgba(0, 240, 255, 0); }
    100% { box-shadow: 0 0 0 0 rgba(0, 240, 255, 0); }
}

/* Dashboard Phase 2 */
.dashboard {
    padding: calc(80px + 2rem) var(--padding-x) 4rem var(--padding-x);
    max-width: 1200px;
    margin: 0 auto;
    animation: fadeIn 0.8s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Sticky Header */
.sticky-header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: 80px;
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--card-border);
    z-index: 90;
    padding: 0 var(--padding-x);
    display: flex;
    flex-direction: column;
    justify-content: center;
    box-shadow: 0 4px 30px rgba(0,0,0,0.1);
}

.header-top {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
    max-width: 1200px;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
}

.subject-title {
    font-weight: 600;
    color: var(--heading-color);
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.current-week {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent-color);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.progress-container {
    max-width: 1200px;
    width: 100%;
    height: 6px;
    background: var(--progress-bg);
    border-radius: 50px;
    margin: 0 auto;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    width: 0%;
    background: var(--progress-fill);
    border-radius: 50px;
    transition: width 1s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: 0 0 10px var(--primary-glow);
}

.progress-labels {
    max-width: 1200px;
    width: 100%;
    margin: 4px auto 0;
    display: flex;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-color);
    opacity: 0.7;
}

/* 7-Week Track Grid */
.grid-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 1rem;
}

.week-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    position: relative;
}

.week-card:hover:not(.locked) {
    transform: translateY(-5px);
    box-shadow: 0 12px 40px rgba(0, 240, 255, 0.15);
}

.week-card.locked {
    cursor: not-allowed;
    background: var(--locked-bg);
    border-color: var(--locked-border);
}

.week-card.locked .beaker-svg {
    filter: var(--locked-filter);
}

.week-card.locked .week-title {
    opacity: 0.5;
}

.week-card.locked .status-icon {
    margin-top: 1rem;
    font-size: 1.5rem;
    opacity: 0.6;
}

.beaker-container {
    height: 120px;
    margin-bottom: 1.5rem;
    position: relative;
}

.beaker-svg {
    height: 100%;
    width: auto;
    transition: filter var(--transition-speed);
}

/* Glowing Beaker Styles */
.beaker-fluid {
    fill: url(#glowGradient);
    animation: pulseGlow 2s infinite alternate;
}

.week-card.completed .beaker-fluid {
    fill: #27ae60; 
}

@keyframes pulseGlow {
    from { opacity: 0.8; filter: drop-shadow(0 0 5px var(--primary-glow)); }
    to { opacity: 1; filter: drop-shadow(0 0 15px var(--secondary-glow)); }
}

.week-title {
    font-size: 1.4rem;
    font-weight: 600;
    color: var(--heading-color);
    margin-bottom: 0.5rem;
}

.week-desc {
    font-size: 0.95rem;
    opacity: 0.8;
}

.status-icon {
    margin-top: 1rem;
    font-size: 1.5rem;
}

.status-badge {
    position: absolute;
    top: -10px;
    right: -10px;
    background: #27ae60;
    color: white;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    box-shadow: 0 4px 10px rgba(39, 174, 96, 0.4);
    opacity: 0;
    transform: scale(0);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.week-card.completed .status-badge {
    opacity: 1;
    transform: scale(1);
}

/* Modals */
.modal {
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0, 0, 0, 0.85);
    backdrop-filter: blur(10px);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    opacity: 0;
    visibility: hidden;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.modal:not(.hidden) {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--bg-color); /* solid for better image viewing */
    width: 100%;
    display: flex;
    flex-direction: column;
    position: relative;
    border: 1px solid var(--card-border);
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.5);
    border-radius: 20px;
    overflow: hidden;
    transform: scale(0.95) translateY(20px);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.small-modal {
    max-width: 500px;
    min-height: 400px;
}

.full-screen-modal {
    max-width: 100vw;
    height: 100vh;
    border-radius: 0;
    border: none;
    background: #000; /* Pure black for deep zoom */
}

.modal:not(.hidden) .modal-content {
    transform: scale(1) translateY(0);
}

.close-btn {
    position: absolute;
    top: 15px;
    right: 15px;
    background: rgba(0,0,0,0.5);
    color: white;
    border: 2px solid rgba(255,255,255,0.2);
    width: 40px; height: 40px;
    border-radius: 50%;
    font-size: 1.5rem;
    cursor: pointer;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition-speed);
}
.close-btn:hover {
    background: var(--accent-color);
    transform: rotate(90deg);
}

.glow-close-btn {
    background: rgba(255, 0, 0, 0.6);
    border: 1px solid rgba(255, 100, 100, 0.5);
    top: 25px;
    right: 30px;
}

.glow-close-btn:hover {
    background: red;
    box-shadow: 0 0 15px red;
}

.modal-title {
    padding: 1.5rem;
    font-size: 1.5rem;
    border-bottom: 1px solid var(--card-border);
    color: var(--heading-color);
    font-weight: 600;
}

.modal-body-content {
    padding: 2rem;
    text-align: center;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.view-btn {
    margin-top: 2rem;
}

.glow-pulse {
    animation: glowPulse 1.5s infinite alternate;
}

@keyframes glowPulse {
    from { box-shadow: 0 0 10px var(--accent-color); }
    to { box-shadow: 0 0 30px var(--primary-glow); border-color: var(--primary-glow); }
}

.image-scroll-container {
    flex-grow: 1;
    position: relative;
    overflow-y: auto;
    overflow-x: hidden;
    background: #000;
    display: flex;
    flex-direction: column;
    align-items: center;
    width: 100%;
    height: 100vh;
    padding: 2rem 0;
}

.image-scroll-container img {
    max-width: 100%;
    height: auto;
}

.modal-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--card-border);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.hint-text {
    font-size: 0.85rem;
    color: var(--accent-color);
    opacity: 0.8;
}

/* Celebration Popup */
.celebration-popup {
    position: fixed;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.5);
    background: var(--card-bg);
    backdrop-filter: blur(20px);
    padding: 3rem 4rem;
    border-radius: 20px;
    border: 2px solid var(--accent-color);
    box-shadow: 0 0 50px var(--primary-glow-alpha);
    z-index: 3000;
    text-align: center;
    opacity: 0;
    transition: all 0.5s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.celebration-popup:not(.hidden) {
    transform: translate(-50%, -50%) scale(1);
    opacity: 1;
}

.celebration-text {
    font-size: 4rem;
    font-weight: 800;
    color: var(--heading-color);
    text-shadow: 0 0 20px var(--accent-color);
}

/* Responsive */
@media (max-width: 768px) {
    .greeting { font-size: 2.2rem; }
    .grid-container {
        grid-template-columns: 1fr;
    }
    .celebration-text {
        font-size: 2.5rem;
    }
    .small-modal {
        height: 100vh;
        max-width: 100vw;
        border-radius: 0;
        border: none;
    }
}

/* Floating Timer CSS */
.timer-widget {
    position: fixed;
    bottom: 30px;
    right: 30px;
    z-index: 1000;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 15px;
}

.floating-toggle {
    background: var(--card-bg);
    border: 1px solid var(--primary-glow);
    border-radius: 50%;
    width: 60px;
    height: 60px;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(0,240,255,0.4);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    color: white;
}

.floating-toggle:hover {
    transform: scale(1.1);
}

.timer-panel {
    padding: 20px;
    border-radius: 15px;
    width: 250px;
    text-align: center;
    position: relative;
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
    transition: all 0.3s ease;
    border: 1px solid var(--card-border);
}

.invisible-panel {
    transform: translateY(20px);
    opacity: 0;
    pointer-events: none;
}

.timer-btn {
    border: none;
    border-radius: 8px;
    padding: 8px 15px;
    cursor: pointer;
    font-weight: 600;
    transition: 0.2s;
    background: rgba(255,255,255,0.1);
    color: var(--text-color);
}
.timer-btn.play-btn:hover { background: #27ae60; color: white; }
.timer-btn.stop-btn:hover { background: #e67e22; color: white; }
.timer-btn.reset-btn:hover { background: #c0392b; color: white; }

/* Hub Cards specific */
.hub-card {
    min-height: 250px;
    justify-content: center;
}

/* XO Game Board */
.xo-board {
    display: grid;
    grid-template-columns: repeat(3, 100px);
    grid-template-rows: repeat(3, 100px);
    gap: 10px;
    justify-content: center;
    margin: 0 auto;
}

.xo-cell {
    background: var(--card-bg);
    border: 2px solid var(--accent-color);
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 3.5rem;
    font-weight: bold;
    cursor: pointer;
    box-shadow: 0 0 10px var(--primary-glow-alpha);
    transition: all 0.3s;
}

.xo-cell:hover:not(.taken) {
    background: rgba(0, 240, 255, 0.1);
}

.xo-cell.taken {
    cursor: not-allowed;
}

.mcq-chapter-card {
    padding: 20px;
    font-size: 1.2rem;
    cursor: pointer;
    text-align: center;
    transition: all 0.3s;
}

.mcq-chapter-card:hover {
    transform: scale(1.02);
    box-shadow: 0 0 15px var(--secondary-glow);
}

.game-menu-card:hover {
    transform: scale(1.02);
    box-shadow: 0 0 15px #27ae60;
}

.quiz-option {
    width: 100%;
    padding: 15px 20px;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--card-border);
    border-radius: 12px;
    color: var(--text-color);
    font-size: 1.1rem;
    cursor: pointer;
    text-align: right;
    direction: rtl;
    unicode-bidi: isolate;
    transition: all 0.2s;
}

.quiz-option:hover {
    background: rgba(0, 240, 255, 0.1);
    transform: translateX(-5px);
}

.quiz-option.correct {
    background: rgba(39, 174, 96, 0.3) !important;
    border-color: #27ae60 !important;
}

.quiz-option.incorrect {
    background: rgba(192, 57, 43, 0.3) !important;
    border-color: #c0392b !important;
}

@keyframes floatAnimation {
    0% { transform: translateY(0); }
    50% { transform: translateY(-10px); }
    100% { transform: translateY(0); }
}

.floating-animation {
    animation: floatAnimation 4s ease-in-out infinite;
}

/* Tic-Tac-Toe Difficulty Buttons */
.diff-btn {
    padding: 8px 20px;
    border: 1px solid var(--card-border);
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-color);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    font-weight: 600;
}

.diff-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

.diff-btn.active {
    background: var(--primary-glow);
    color: #111;
    border-color: var(--primary-glow);
    box-shadow: 0 0 10px var(--primary-glow-alpha);
}

/* Snake Game adjustments */
#snakeCanvas {
    display: block;
    box-shadow: 0 0 20px rgba(230, 126, 34, 0.2);
}

.game-menu-card:hover {
    transform: scale(1.02);
    box-shadow: 0 0 15px var(--primary-glow);
}

/* Toggle Switch Styling for Admin */
.switch {
    display: inline-block;
    height: 26px;
    position: relative;
    width: 50px;
}

.switch input {
    display: none;
}

.slider {
    background-color: rgba(255, 255, 255, 0.1);
    bottom: 0;
    cursor: pointer;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    transition: .4s;
    border-radius: 34px;
}

.slider:before {
    background-color: white;
    bottom: 4px;
    content: "";
    height: 18px;
    left: 4px;
    position: absolute;
    transition: .4s;
    width: 18px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    border-radius: 50%;
}

input:checked + .slider {
    background-color: #27ae60;
    box-shadow: 0 0 15px rgba(39, 174, 96, 0.4);
}

input:focus + .slider {
    box-shadow: 0 0 1px #27ae60;
}

input:checked + .slider:before {
    transform: translateX(24px);
}

/* =========================================
   Updates Notification Button Styles
========================================= */
.notification-pulse-btn {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
    color: white;
    padding: 12px 30px;
    font-size: 1.3rem;
    font-weight: bold;
    font-family: 'Outfit', sans-serif;
    border-radius: 30px;
    border: 2px solid #ff7675;
    box-shadow: 0 0 20px rgba(231, 76, 60, 0.6);
    cursor: pointer;
    position: relative;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    animation: heartBeat 2s infinite;
}

.notification-pulse-btn:hover {
    transform: scale(1.05);
    box-shadow: 0 0 30px rgba(231, 76, 60, 0.9);
}

.bell-icon {
    display: inline-block;
    margin-right: 8px;
    animation: ring 2s infinite;
    transform-origin: top center;
}

.badge-new {
    position: absolute;
    top: -10px;
    right: -10px;
    background: #f1c40f;
    color: #333;
    font-size: 0.8rem;
    font-weight: 800;
    padding: 4px 8px;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.3);
    animation: bounce 2s infinite;
}

@keyframes ring {
    0% { transform: rotate(0); }
    10% { transform: rotate(15deg); }
    20% { transform: rotate(-10deg); }
    30% { transform: rotate(5deg); }
    40% { transform: rotate(-5deg); }
    50% { transform: rotate(0); }
    100% { transform: rotate(0); }
}

@keyframes heartBeat {
    0% { transform: scale(1); }
    14% { transform: scale(1.05); }
    28% { transform: scale(1); }
    42% { transform: scale(1.05); }
    70% { transform: scale(1); }
}

@keyframes bounce {
    0%, 20%, 50%, 80%, 100% {transform: translateY(0);}
    40% {transform: translateY(-5px);}
    60% {transform: translateY(-3px);}
}

@keyframes floatPop {
    0% { transform: translateY(0px) scale(1); }
    100% { transform: translateY(-8px) scale(1.02); }
}