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

body {
    font-family: Arial, sans-serif;
    background-color: #f0f8ff;
    color: #333;
    margin: 0;
    padding: 0;
}

/* Header Styles */
.header {
    background-color: #6200ea;
    color: white;
    text-align: center;
    padding: 20px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

header h1 {
    font-size: 3em;
    margin: 0;
    animation: fadeIn 2s ease-in-out;
}

/* Navigation Styles */
nav ul {
    list-style: none;
    display: flex;
    justify-content: center;
    padding: 10px;
    background-color: #3700b3;
}

nav ul li {
    margin: 0 15px;
}

nav ul li a {
    color: white;
    text-decoration: none;
    font-size: 1.2em;
    position: relative;
}

nav ul li a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background-color: #fff;
    left: 50%;
    bottom: -5px;
    transition: width 0.3s ease, left 0.3s ease;
}

nav ul li a:hover::after {
    width: 100%;
    left: 0;
}

/* Content Section Styles */
.content-section {
    padding: 20px;
    margin: 20px auto;
    max-width: 90%;
    text-align: center;
    animation: slideIn 1s ease-in-out;
}

.content-section h2 {
    font-size: 2em;
    margin-bottom: 20px;
    color: #6200ea;
}

.content-section p {
    font-size: 1.2em;
    color: #444;
}

/* Extra Lessons Section Styles */
.extra-lesson-video-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 15px;
    margin-top: 20px;
    
}

video {
    width: 320px;
    height: 180px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease;
}

video:hover {
    transform: scale(1.05);
}

/* Animation Styles */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

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

/* Notations Section Styles */
.notation-image {
    width: 80%;
    max-width: 600px;
    margin-top: 20px;
    border: 2px solid #6200ea;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.download-btn {
    background-color: #3700b3;
    color: white;
    border: none;
    padding: 10px 20px;
    font-size: 1.2em;
    cursor: pointer;
    margin-top: 20px;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

.download-btn:hover {
    background-color: #6200ea;
}

/* Footer Styles */
.footer {
    background-color: #3700b3;
    color: white;
    text-align: center;
    padding: 10px;
    position: fixed;
    bottom: 0;
    width: 100%;
}
.footer a:hover {
    color: #eee;
        width: 100%;
         left: 0;
}

.footer a {
    color: lightgray;
    text-decoration: none;
}
/* Tab Content Styles */
.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

/* Video Level Title */
.level-title {
    font-size: 1.7em;
    color: #6200ea;
    margin-top: 40px;
}
@media (max-width: 700px) {
    nav ul {
        flex-direction: column;
        align-items: center;
    }
    nav ul li {
        margin: 10px 0;
    }
    .content-section {
        padding: 10px;
        margin: 10px auto;
    }
    .level-title {
        font-size: 1.1em;
    }
    .notation-image {
        width: 100%;
        max-width: 100%;
    }
    video,
    .extra-lesson-video-container video,
    .video-container iframe {
        width: 100% !important;
        max-width: 100% !important;
        height: auto !important;
        aspect-ratio: 16/9;
    }
    .video-container,
    .extra-lesson-video-container {
        flex-direction: column;
        gap: 10px;
    }
    header h1 {
        font-size: 2em;
    }
}
.video-container iframe,
.extra-lesson-video-container iframe {
    width: 100%;
    max-width: 320px;
    height: auto;
    aspect-ratio: 16/9;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s ease;
}
.theme-switcher {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: 8px;
    margin-top: 10px;
}

#theme-select {
    padding: 4px 8px;
    border-radius: 5px;
    border: 1px solid #ccc;
    font-size: 1em;
}

/* Default Theme (base) */
body.theme-default {
    --bg: #f0f8ff;
    --header: #6200ea;
    --nav: #3700b3;
    --accent: #6200ea;
    --text: #333;
    --section-bg: #fff;
}

/* Midnight Theme */
body.theme-midnight {
    --bg: #181c2f;
    --header: #232946;
    --nav: #121629;
    --accent: #eebbc3;
    --text: #eaeaea;
    --section-bg: #232946;
}

/* Sunset Theme */
body.theme-sunset {
    --bg: #fff4e6;
    --header: #ff6f3c;
    --nav: #ff9a3c;
    --accent: #ff6f3c;
    --text: #3d2c29;
    --section-bg: #ffe0b2;
}

/* Forest Theme */
body.theme-forest {
    --bg: #e8f5e9;
    --header: #388e3c;
    --nav: #2e7d32;
    --accent: #43a047;
    --text: #1b5e20;
    --section-bg: #c8e6c9;
}

/* Aqua Theme */
body.theme-aqua {
    --bg: #e0f7fa;
    --header: #00bcd4;
    --nav: #00838f;
    --accent: #00acc1;
    --text: #004d40;
    --section-bg: #b2ebf2;
}
/* Matrix Theme */
body.theme-matrix {
    --bg: #0f2027;
    --header: #1a3c1a;
    --nav: #162c16;
    --accent: #39ff14;
    --text: #39ff14;
    --section-bg: #162c16;
}

/* Pastel Theme */
body.theme-pastel {
    --bg: #fdf6fd;
    --header: #b5ead7;
    --nav: #ffdac1;
    --accent: #ffb7b2;
    --text: #444;
    --section-bg: #c7ceea;
}

/* Lava Theme */
body.theme-lava {
    --bg: #2d0606;
    --header: #ff4500;
    --nav: #b22222;
    --accent: #ff6347;
    --text: #fff3e0;
    --section-bg: #7c0a02;
}

/* Ice Theme */
body.theme-ice {
    --bg: #e0f7fa;
    --header: #81d4fa;
    --nav: #0288d1;
    --accent: #00bcd4;
    --text: #01579b;
    --section-bg: #b3e5fc;
}

/* Galaxy Theme */
body.theme-galaxy {
    --bg: #1a0033;
    --header: #3d0066;
    --nav: #29004d;
    --accent: #ffb347;
    --text: #e0e0ff;
    --section-bg: #3d0066;
}

/* Retro Theme */
body.theme-retro {
    --bg:rgb(250, 255, 183);
    --header: #b2ff47;
    --nav: #61edff;
    --accent: #96abfd;
    --text: #333;
    --section-bg: #fde3f1;
}

body {
    background-color: var(--bg);
    color: var(--text);
}
.header {
    background-color: var(--header);
    color: var(--text);
}
nav ul {
    background-color: var(--nav);
}
.level-title,
.content-section h2 {
    color: var(--accent);
}
.content-section {
    background: var(--section-bg);
    border-radius: 10px;
}
.download-btn {
    background-color: var(--nav);
}
.download-btn:hover {
    background-color: var(--accent);
}
.footer {
    background-color: var(--nav);
    color: var(--text);
}
.notation-image {
    border-color: var(--accent);
}
a, .nav-link {
    color: var(--accent);
}
a:hover, .nav-link:hover {
    color: var(--header);
}
.hidden {
    display: none;
}
.theme-switcher select {
    transition: opacity 0.2s;
}
.theme-switcher select.show {
    display: inline-block;
    opacity: 1;
}
@media (min-width: 700px) {
    html, body {
        height: 100%;
    }
    body {
        min-height: 100vh;
        display: flex;
        flex-direction: column;
    }
    main {
        flex: 1 0 auto;
    }
    .footer {
        flex-shrink: 0;
        position: sticky;
        bottom: 0;
        left: 0;
        width: 100%;
        background-color: var(--nav);
        color: var(--text);
        text-align: center;
        padding: 10px;
        box-sizing: border-box;
    }
}

/* On small screens, footer is just static */
@media (max-width: 699px) {
    .footer {
        position: static;
    }
}
body {
    transition: background-color 0.4s, color 0.4s;
}
.header, nav ul, .content-section, .footer {
    transition: background-color 0.4s, color 0.4s;
}
.nav-link.active, nav ul li a.active {
    font-weight: bold;
    border-bottom: 2px solid var(--accent);
    color: var(--accent);
}
body::-webkit-scrollbar {
    width: 8px;
    background: var(--section-bg);
}
body::-webkit-scrollbar-thumb {
    background: var(--accent);
    border-radius: 4px;
}
.enlarge {
    font-size: 1.2em;
}
.timer-stats {
    background: var(--section-bg, #f9f9f9);
    border-radius: 10px;
    padding: 15px;
    margin-top: 20px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
    text-align: center;
}
.timer-stats h3 {
    margin-top: 0;
}
.timer-stats button {
    margin: 0 5px;
    padding: 6px 14px;
    border-radius: 5px;
    border: none;
    background: var(--accent, #39ff14);
    color: #222;
    cursor: pointer;
    font-weight: bold;
}
.timer-stats button:hover {
    background: var(--header, #232946);
    color: #fff;
}