.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    max-width: 100%;
    background: #000;
    margin-bottom: 20px;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* Theme Container */
#video-content {
    padding: 40px;
    margin: 20px auto;
    max-width: 800px;
    border-radius: 8px;
    line-height: 1.8;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    transition: background-color 0.3s, color 0.3s;
}

/* Theme Trigger Button */
#theme-trigger {
    position: absolute;
    top: 0;
    right: 0;
    background: transparent;
    border: 1px solid #ccc;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    font-weight: bold;
    cursor: pointer;
    font-family: serif;
    font-size: 1.2em;
    color: #666;
    border-color: #666;
    z-index: 10;
    transition: all 0.2s;
}

#theme-trigger:hover {
    background: rgba(0, 0, 0, 0.1);
    border-color: #333;
    color: #333;
}

/* Dialog Styling */
#theme-dialog {
    border: none;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    padding: 20px;
    max-width: 300px;
    width: 100%;
}

#theme-dialog::backdrop {
    background: rgba(0, 0, 0, 0.3);
}

#theme-dialog h3 {
    margin-top: 0;
    margin-bottom: 15px;
    font-size: 1.1em;
    color: #333;
}

.theme-options {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.theme-options button {
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9em;
    transition: transform 0.1s;
}

.theme-options button:hover {
    transform: scale(1.05);
}

.btn-close {
    background: none;
    border: none;
    color: #666;
    cursor: pointer;
    font-size: 0.9em;
    text-decoration: underline;
}

/* Theme: Light (Default) - Black text on White background */
.theme-light {
    background-color: #ffffff;
    color: #222222;
    border: 1px solid #eee;
}

.theme-light h1 { color: #333; }
.theme-light .tauthor, .theme-light .tdate { color: #666; }
.theme-light p { color: #444; }

/* Theme: Dark - White text on Black background */
.theme-dark {
    background-color: #252525;
    color: #e0e0e0;
    border: 1px solid #444;
}

.theme-dark h1 { color: #fff; }
.theme-dark .tauthor, .theme-dark .tdate { color: #aaa; }
.theme-dark p { color: #ccc; }
.theme-dark #theme-trigger { color: #e0e0e0; border-color: #aaa; }

/* Theme: Grey - Dark text on Grey background (Low Contrast/Easy on eyes) */
.theme-grey {
    background-color: #f4f4f4;
    color: #333333;
    border: 1px solid #ddd;
}

.theme-grey h1 { color: #222; }
.theme-grey .tauthor, .theme-grey .tdate { color: #555; }
.theme-grey p { color: #333; }

/* Button Styles for Dialog */
.btn-theme-light { background: #fff; color: #000; }
.btn-theme-dark { background: #333; color: #fff; }
.btn-theme-grey { background: #eee; color: #333; }

h1 {
    font-size: clamp(1.5rem, 5vw + 1rem, 2.5rem);
    margin-bottom: 10px;
}