body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #1e1e1e;
    color: #d4d4d4;
    margin: 0;
    padding: 0;
}

header {
    background-color: #333;
    padding: 10px 20px;
    text-align: center;
    border-bottom: 2px solid #555;
}

header h1 {
    margin: 0;
    font-size: 1.8em;
    color: #f0f0f0;
    text-shadow: 2px 2px 4px #000;
}

.container {
    display: flex;
    padding: 20px;
    gap: 20px;
}

.column {
    background-color: #2a2a2a;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0,0,0,0.5);
    flex: 1;
}

#upload-group {
    padding: 15px;
    margin-bottom: 20px;
    background-color: #333;
    border-radius: 5px;
    display: flex;
    align-items: center;
}

#upload-group label {
    width: auto;
    margin-right: 15px;
    font-weight: bold;
}

#upload-group input[type="file"] {
    color: #d4d4d4;
}

#upload-group input[type="file"]::file-selector-button {
    background-color: #4da6ff;
    color: white;
    border: none;
    padding: 8px 12px;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
    margin-right: 10px;
}

#upload-group input[type="file"]::file-selector-button:hover {
    background-color: #66b3ff;
}

#source-column {
    flex-basis: 40%;
}

#preview-column {
    flex-basis: 60%;
}

h2 {
    color: #4da6ff;
    border-bottom: 1px solid #444;
    padding-bottom: 5px;
    margin-top: 0;
}

video, canvas {
    width: 100%;
    background-color: #000;
    border-radius: 4px;
    border: 1px solid #444;
}

.controls-group {
    background-color: #333;
    padding: 15px;
    border-radius: 5px;
    margin-top: 20px;
}

.controls-group h3 {
    margin-top: 0;
    color: #ccc;
}

.time-inputs {
    display: flex;
    align-items: center;
    margin-bottom: 10px;
}

label {
    margin-right: 10px;
    width: 50px;
}

input[type="number"], input[type="range"], input[type="checkbox"] {
    margin-right: 10px;
}
input[type="number"] {
    width: 70px;
    padding: 5px;
    background-color: #1e1e1e;
    color: #d4d4d4;
    border: 1px solid #555;
    border-radius: 3px;
}

button {
    background-color: #4da6ff;
    color: white;
    border: none;
    padding: 8px 12px;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s;
}

button:hover {
    background-color: #66b3ff;
}

button:active {
    background-color: #3385d6;
}

#setStartBtn, #setEndBtn {
    padding: 5px 10px;
}


.preview-controls {
    margin: 10px 0;
    display: flex;
    gap: 10px;
}

#clearTimelineBtn {
    background-color: #ff4d4d;
}
#clearTimelineBtn:hover {
    background-color: #ff6666;
}
#clearTimelineBtn:active {
    background-color: #d63333;
}


#timeline {
    background-color: #1e1e1e;
    border: 1px solid #444;
    padding: 10px;
    min-height: 100px;
    max-height: 300px;
    overflow-y: auto;
    border-radius: 4px;
}

.timeline-clip {
    background-color: #333;
    padding: 8px;
    margin-bottom: 5px;
    border-radius: 3px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-left: 4px solid #4da6ff;
}

.timeline-clip.reversed {
    border-left-color: #ff9a4d;
}

.timeline-clip span {
    font-size: 0.9em;
}

.clip-delete-btn {
    background-color: #ff6666;
    color: white;
    border: none;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    cursor: pointer;
    font-weight: bold;
    line-height: 20px;
    text-align: center;
    padding: 0;
}