:root {
        --bg:#FFFFFF;
        --bgc:#3399FF;
        --text:#262626;
        --border:#262626;
        --border_w:3px;
        --radius:5px;
        --danger:#F44336;
    }

    *, *::before, *::after {
        box-sizing: border-box;
    }

    body {
        font-family: Arial, sans-serif;
        background-color: #f4f4f4;
        margin: 0;
        padding: 20px;
    }

    button {
        display: block;
        width: 100%;
        padding: 10px;
        margin: 5px 0;
        background-color: #ffffff;
        border: 3px solid #262626;
        color: #262626;
        border-radius: 5px;
        cursor: pointer;
        font-size: 1em;
        transition: background-color 0.3s ease;
    }

    button:hover {
        background-color: #262626;
        border: 3px solid #262626;
        color: white;
    }

    .container {
        max-width:1000px;
        width:min(1000px, calc(100% - 24px));
        margin:20px auto;
        background:#F1F1F1;
        padding:20px;
        border:var(--border_w) solid var(--border);
        border-radius:var(--radius);
        text-align:center;
        box-shadow:0 4px 12px rgba(0,0,0,0.3);
    }

    .custom-file-container {
        width: 100%;
        padding: 10px;
        border: 3px dashed #262626;
        border-radius: 5px;
        text-align: center;
        background-color: #ffffff;
        margin: 5px 0;
        position: relative;
        box-sizing: border-box;
    }

    .custom-file-container.hover {
        border-color: #3399FF; 
        background-color: #DDEEFF; 
    }

    .custom-file-container .file-input {
        display: none;
    }

    .custom-file-container .file-btn {
        background-color: #ffffff;
        border: 3px solid #262626;
        width: auto; 
        display: inline-block;
        color: #262626;
        padding: 10px 20px;
        border-radius: 5px;
        cursor: pointer;
        transition: background-color 0.3s;
    }

    .custom-file-container .file-btn:hover {
        background-color: #262626;
        border: 3px solid #262626;
        color: white;
    }

    .custom-file-container .file-btn.delete-sentence-btn {
        border-color: #f44336;
        color: #f44336;
        background-color: #ffffff;
    }
    .custom-file-container .file-btn.delete-sentence-btn:hover {
        background-color: #f44336;
        border-color: #f44336;
        color: #ffffff;
    }

    .color-picker-btn {
        display: inline-block;
        padding: 10px 20px;
        border: 3px solid #262626;
        border-radius: 5px;
        background: #ffffff;
        color: #262626;
        font-size: 1em;
        cursor: pointer;
        transition: background-color 0.3s, color 0.3s;
        width: auto; 
    }
    .color-picker-btn:hover {
        background-color: #262626;
        color: #ffffff;
    }

    .color-picker-info {
        margin-top: 1px; 
        font-size: 0.8em;
        line-height: 1; 
        color: #262626;
    }

    .sentence-container button.delete-sentence-btn {
        display: inline-block;
        width: auto;
        min-width: 0;
        padding: 10px 20px;
        margin: 10px auto 5px auto;
        background-color: transparent;
        border: 3px solid #f44336;
        color: #f44336;
        border-radius: 4px;
        cursor: pointer;
        font-size: 0.9em;
        transition: background-color 0.2s ease;
    }

    .sentence-container button.delete-sentence-btn:hover {
        background-color: #f44336;
        color: #ffffff;
    }

    .custom-file-container .file-status {
        display: block;
        margin-top: 1px;
        font-size: 0.8em;
        color: #262626;
        text-align: center;
    }

    .custom-file-container .btn-input {
        display: none; 
    }

    .custom-file-container .btn-input {
        display: inline-block;
        width: auto;
        padding: 10px 20px;
        margin-left: 10px;
        border: 3px solid #262626;
        border-radius: 5px;
        font-size: 1em;
        background-color: #ffffff;
        cursor: pointer;
        transition: background-color 0.3s;
    }

    .custom-file-container .btn-input:hover {
        background-color: #262626;
        color: white;
    }

    .duration-block {
        display: flex;
        flex-direction: column;
        align-items: center; 
        margin: 10px auto;
    }

    .duration-block label {
        display: block;
        margin-top: 1px;
        font-size: 0.8em;
        color: #262626;
        text-align: center;
    }

    .duration-input {
        display: block;
        width: 60px !important; 
        padding: 10px 20px;
        border: 3px solid #262626;
        border-radius: 4px;
        box-sizing: border-box;
        align-items: center;
    }

    #download-video-btn {
        display: inline-block;
        width: auto; 
        padding: 10px 20px;
        background-color: #ffffff;
        border: 3px solid #262626;
        color: #262626;
        border-radius: 5px;
        cursor: pointer;
        font-size: 1em;
        transition: background-color 0.3s ease;
        margin: 10px auto;
    }
    #download-video-btn:hover {
        background-color: #262626;
        border: 3px solid #262626;
        color: #ffffff;
    }

    h1, h2 {
        text-align: center;
        color: #262626;
    }

    .form-section label {
        display: block;
        margin: 10px 0 5px;
    }

    input[type="text"],
    input[type="number"],
    select,
    input[type="color"] {
        width: 100%;
        padding: 10px;
        margin-bottom: 10px;
        border: 3px solid #262626;
        border-radius: 5px;
        box-sizing: border-box;
        display: inline-block;
        font-family: Arial, sans-serif;
    }

    #voice-select,
    #voice-select optgroup,
    #voice-select option {
        font-style: normal;
    }

    #voice-select option {
        font-weight: 400;
    }

    #voice-select option.voice-disabled-option,
    #voice-select option[value="none"] {
        font-weight: 700;
    }

    .spinner {
        border: 8px solid #262626;
        border-top: 8px solid #3399FF;
        border-radius: 50%;
        width: 50px;
        height: 50px;
        animation: spin 1s linear infinite;
        margin: 20px auto;
    }

    .sentence-container {
        border: 3px solid #262626;
        border-radius: 5px;
        margin-bottom: 10px;
        background: #fff;
        overflow: hidden;
    }

    .sentence-container > summary {
        padding: 10px;
        cursor: pointer;
        font-weight: bold;
        list-style: none;
        display: flex;
        align-items: center;
        justify-content: center;
        gap: 10px;
    }

    .sentence-drag-handle {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 32px;
        height: 32px;
        cursor: grab;
        user-select: none;
        color: inherit;
        background-color: currentColor;
        -webkit-mask: url('/static/icons/move-vertical.svg') center / 24px 24px no-repeat;
        mask: url('/static/icons/move-vertical.svg') center / 24px 24px no-repeat;
    }

    .sentence-drag-handle:active {
        cursor: grabbing;
    }

    .sentence-ghost {
        opacity: .55;
        background: #DDEEFF;
    }

    .sentence-chosen > summary {
        background: #DDEEFF;
        color: #262626;
    }

    .sentence-container[open] > summary {
        background-color: #262626;
        color: #fff;
    }

    .sentence-body {
        padding: 10px;
        border-top: 1px solid #ccc;
    }

    @keyframes spin {
      0% { transform: rotate(0deg); }
      100% { transform: rotate(360deg); }
    }

    #sentences .sentence-container {
        margin-bottom: 10px;
        padding: 10px;
        border: 3px solid #262626;
        border-radius: 5px;
    }

    #sentences textarea {
        width: 100%;
        padding: 8px;
        margin: 5px 0;
        box-sizing: border-box;
        font-family: Arial, sans-serif;
        resize: none;
        border: 3px solid #262626;
        border-radius: 5px
    }

    #sentences .image-input {
        display: block;
        width: 100%;
        padding: 20px;
        margin: 5px 0;
        border: 3px dashed #262626;
        border-radius: 5px;
        text-align: center;
        cursor: pointer;
        background-color: #ffffff;
        transition: background-color 0.3s, border-color 0.3s;
    }

    #sentences .file-hint {
        display: block;
        margin-top: 1px;
        font-size: 0.9em;
        color: #262626;
    }

    #sentences .image-input.hover {
        border-color: #054b7a;
        background-color: #e0f7ff;
    }

    #sentences .image-input::file-selector-button {
        background-color: #2980b9;
        color: white;
        border: none;
        padding: 10px 20px;
        margin-right: 10px;
        border-radius: 5px;
        cursor: pointer;
        transition: background-color 0.3s ease;
    }

    #sentences .image-input::file-selector-button:hover {
        background-color: #054b7a;
    }

    #sentences .color-picker-wrapper {
        margin: 12px 0 18px 0 !important;
    }

    #sentences .sentence-media-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
        gap: 16px;
        align-items: start;
        margin: 6px 0 14px 0;
    }

    #sentences .sentence-media-field {
        min-width: 0;
    }

    #sentences .sentence-media-field .custom-file-container {
        min-height: 112px;
        height: auto;
        margin: 0;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    }

    #sentences .sentence-media-label {
        display: block;
        margin: 0 0 8px 0;
        font-weight: 600;
        color: #262626;
    }

    #sentences .sentence-audio-upload {
        display: none;
    }

    #sentences .sentence-audio-upload.is-visible {
        display: block;
    }

    #sentences .audio-file-hint {
        display: block;
        margin: 6px 0 0 0;
        font-size: 0.9em;
        color: #262626;
    }

    #result-container {
        text-align: center;
    }

    pre {
        background: #ffffff;
        padding: 10px;
        overflow-x: auto;
    }

    .video-config-row {
        display: flex;
        gap: 15px;
        flex-wrap: wrap;
        margin-bottom: 22px;
        justify-content: space-between;
        align-items: flex-start;
    }

    .video-config-row-main {
        margin-top: 8px;
    }

    .video-config-item {
        flex: 1 1 140px;
        display: flex;
        flex-direction: column;
        min-width: 140px;
    }

    .video-config-item-voice {
        flex-basis: 160px;
    }

    .video-config-item-didactic-style {
        flex: 0 1 160px;
        min-width: 150px;
    }

    .video-config-item-duration {
        flex: 0 1 120px;
        min-width: 115px;
    }

    .video-config-item-topic {
        flex: 2 1 240px;
        min-width: 220px;
    }

    .video-config-item-topic input[type="text"] {
        margin: 0;
        min-height: 41px;
    }

    .video-config-item-fps {
        flex: 0 0 80px;
        min-width: 80px;
        align-items: center;
    }

    .video-config-item-fps > label {
        width: 100%;
        text-align: center;
    }

    .video-config-item-fps .duration-input {
        margin-left: auto;
        margin-right: auto;
        text-align: center;
    }

    .video-config-item-wide {
        flex: 1 1 100%;
    }

    .video-config-item > label {
        margin-bottom: 8px;
        color: #262626;
        font-weight: 600;
    }

    .upload-fields-row {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 16px;
        align-items: start;
        margin: 18px 0 24px 0;
    }

    .upload-fields-row .process-field {
        margin: 0;
        display: flex;
        flex-direction: column;
        align-items: stretch;
        min-width: 0;
    }

    .upload-fields-row .custom-file-container {
        min-height: 102px;
        height: auto;
        box-sizing: border-box;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    }

    .upload-fields-row + .process-field {
        margin-top: 0;
    }

    .process-field {
        margin: 18px 0 0 0;
        text-align: center;
    }

    .process-field-label {
        display: block;
        margin: 0 0 10px 0;
        color: #262626;
        font-weight: 600;
        line-height: 1.3;
    }

    .upload-format-hint {
        display: block;
        margin-top: 3px;
        font-size: 0.78em;
        font-weight: 400;
        line-height: 1.2;
        color: #555;
    }

    .process-field .custom-file-container,
    .process-field input[type="text"],
    .process-field input[type="number"],
    .process-field select {
        margin-top: 0;
        margin-bottom: 0;
    }

    .subtitle-options-panel,
    .audio-options-panel {
        margin: 18px 0 22px 0;
        padding: 16px;
        background: #ffffff;
        border: 3px solid #262626;
        border-radius: 5px;
        text-align: left;
        box-shadow: 0 2px 6px rgba(0, 0, 0, 0.12);
    }

    .subtitle-panel-header,
    .audio-panel-header {
        display: flex;
        justify-content: space-between;
        align-items: center;
        margin: 0 0 12px 0;
        padding: 0;
    }

    .subtitle-panel-header h3,
    .audio-panel-header h3 {
        margin: 0;
        color: #262626;
        font-size: 1.05em;
        line-height: 1.2;
    }

    .subtitle-settings-row,
    .audio-settings-row {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(145px, 1fr));
        gap: 12px;
        align-items: end;
        margin-top: 0;
    }

    .subtitle-config-item,
    .audio-config-item {
        display: flex;
        flex-direction: column;
        min-width: 0;
    }

    .subtitle-config-item label,
    .audio-config-item label {
        color: #262626;
        font-weight: 600;
        font-size: 0.92em;
        line-height: 1.25;
    }

    .subtitle-config-item label,
    .audio-config-item label {
        margin: 0 0 8px 0;
    }

    .subtitle-config-item input,
    .subtitle-config-item select,
    .audio-config-item input,
    .audio-config-item select {
        margin: 0;
        width: 100%;
        min-height: 44px;
    }


    @media (max-width: 900px) {
        .subtitle-settings-row,
        .audio-settings-row {
            grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
        }

    }

    .form-section label,
    #script-container {
        margin-bottom: 10px;
    }

    .script-action-row {
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 12px;
        align-items: stretch;
        margin: 12px 0 10px 0;
    }

    .script-action-row button {
        width: 100%;
        margin: 0;
    }

    @media (max-width: 640px) {
        .script-action-row {
            grid-template-columns: 1fr;
        }
    }

    .intro-outro-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 16px;
        align-items: stretch;
        margin: 0 0 18px 0;
    }

    .intro-outro-card {
        margin: 0;
        min-width: 0;
        display: flex;
        flex-direction: column;
        align-items: stretch;
    }

    .intro-outro-card > label {
        display: block;
        margin: 0 0 10px 0;
        color: #262626;
        font-weight: 600;
    }

    .intro-outro-card .custom-file-container {
        flex: 1;
        min-height: 124px;
        margin: 0;
        display: flex;
        flex-direction: column;
        justify-content: center;
        align-items: center;
    }

    #intro-config,
    #outro-config {
        margin-bottom: 0;
    }

    input[type="text"],
    select,
    input[type="color"] {
        transition: border-color .2s ease, box-shadow .2s ease;
    }

    input[type="text"]:focus,
    input[type="number"]:focus,
    select:focus,
    input[type="color"]:focus {
        outline: none; 
        border: 3px solid #3399FF;  
        box-shadow: 0 0 0 3px rgba(51, 153, 255, .35);
    }

    #generateBtn {
        margin-top: 1rem; 
    }

    .error-message {
        display: block;
        color: #f44336;
        font-weight: bold;
        background-color: #ffffff; 
        padding: 10px; 
        border-radius: 5px; 
        border: 3px solid #f44336;
        text-align: center; 
        margin-top: 10px;
        margin-bottom: 10px;
        opacity: 1;
        transition: opacity 0.5s ease;
    }

    .error-message.hide {
        opacity: 0;
    }

    .hidden { display: none; }

    .job-progress {
        margin-top: 10px;
        background: #fff;
        border: 3px solid #262626;
        border-radius: 6px;
        padding: 12px;
    }

    .job-progress-text {
        margin-bottom: 8px;
        font-weight: 600;
        color: #262626;
    }

    .progress-outer {
        border: 3px solid #262626;  
        border-radius: 0;    
        background-color: #262626;  
        height: 20px;
        width: 100%;
        padding: 0;
    }

    .progress-inner {
        background-color: #3399FF; 
        height: 100%;
        width: 0%;
        border-radius: 0;
        transition: width 0.3s ease;
    }

    .container.is-processing .video-config-row,
    .container.is-processing .upload-fields-row,
    .container.is-processing > .process-field,
    .container.is-processing #generateBtn,
    .container.is-processing #script-container > h2,
    .container.is-processing .intro-outro-grid,
    .container.is-processing #sentences,
    .container.is-processing #add-sentence-btn,
    .container.is-processing #generate-video-btn,
    .container.is-processing .api-key-config-hint {
        opacity: .42;
        filter: grayscale(.35);
        pointer-events: none;
        user-select: none;
    }

    .container.is-processing #job-progress,
    .container.is-processing #job-progress * {
        opacity: 1;
        filter: none;
        pointer-events: auto;
    }



    .modal-overlay {
        position:fixed;
        inset:0;
        background:rgba(0,0,0,.45);
        display:flex;
        align-items:center;
        justify-content:center;
        padding:16px;
        z-index:9999;
    }

    .modal-overlay[hidden] { display:none; }

    .modal {
        width:min(620px, 100%);
        background:#FFFFFF;
        border:var(--border_w) solid var(--border);
        border-radius:var(--radius);
        padding:18px;
        box-shadow:0 4px 16px rgba(0,0,0,.35);
        text-align:left;
    }

    .modal-title {
        font-weight:600;
        font-size:16px;
        margin:0 0 8px 0;
    }

    .modal-text {
        font-size:14px;
        color:#444;
        line-height:1.35;
        margin:0 0 14px 0;
    }

    .modal-actions {
        display:flex;
        gap:10px;
        justify-content:flex-end;
        flex-wrap:wrap;
        margin-top:14px;
    }

    .btn {
        background:#FFFFFF;
        color:#262626;
        border:3px solid #262626;
        padding:10px 14px;
        border-radius:5px;
        font-size:15px;
        cursor:pointer;
        transition:background-color .12s ease, color .12s ease, transform .05s ease;
        display:inline-flex;
        align-items:center;
        gap:8px;
        text-decoration:none;
        justify-content:center;
        width:auto;
        margin:0;
        box-sizing:border-box;
    }

    .btn:hover {
        background:#262626;
        color:#FFFFFF;
    }

    .btn:active {
        transform:translateY(1px);
    }

    .btn-danger {
        border-color:#F44336;
        color:#F44336;
    }

    .btn-danger:hover {
        background:#F44336;
        color:#FFFFFF;
        border-color:#F44336;
    }

    .sr-only {
        position:absolute;
        width:1px;
        height:1px;
        padding:0;
        margin:-1px;
        overflow:hidden;
        clip:rect(0,0,0,0);
        white-space:nowrap;
        border:0;
    }

    .flvm-topbar {
        position:relative;
        display:flex;
        align-items:flex-start;
        justify-content:center;
        gap:12px;
        margin-bottom:24px;
        min-height:56px;
    }

    .flvm-title-block {
        flex:1 1 auto;
        text-align:center;
        padding:0 68px;
    }

    .flvm-topbar h1 {
        margin:0;
    }

    .flvm-process-id {
        margin-top:8px;
        color:var(--bgc);
        font-size:14px;
        font-weight:700;
        letter-spacing:.04em;
        text-align:center;
        overflow-wrap:anywhere;
    }

    .flvm-actions {
        position:absolute;
        top:0;
        right:0;
        display:flex;
        align-items:center;
        gap:12px;
        flex-wrap:wrap;
        justify-content:flex-end;
    }

    .flvm-icon-btn {
        width:48px;
        height:48px;
        display:inline-flex;
        align-items:center;
        justify-content:center;
        background:#FFFFFF;
        border:3px solid #262626;
        border-radius:8px;
        text-decoration:none;
        transition:background-color .2s ease, border-color .2s ease;
        position:relative;
        padding:0;
        margin:0;
        box-sizing:border-box;
        appearance:none;
        -webkit-appearance:none;
        line-height:1;
        cursor:pointer;
        flex:0 0 48px;
    }

    .flvm-icon-btn:hover {
        background:#3399FF;
        border-color:#262626;
        color:#262626;
    }

    .flvm-icon {
        width:24px;
        height:24px;
        display:inline-block;
        background-color:#262626;
        transition:background-color .2s ease;
        mask-repeat:no-repeat;
        -webkit-mask-repeat:no-repeat;
        mask-position:center;
        -webkit-mask-position:center;
        mask-size:contain;
        -webkit-mask-size:contain;
    }

    .flvm-icon-btn:hover .flvm-icon {
        background-color:#262626;
    }

    .flvm-icon-back {
        mask-image:url('/static/icons/arrow-left-to-line.svg');
        -webkit-mask-image:url('/static/icons/arrow-left-to-line.svg');
    }

    .api-key-config-hint {
        width:100%;
        padding:10px;
        margin-bottom:10px;
        border:3px solid #262626;
        border-radius:5px;
        background:#FFFFFF;
        color:#262626;
        font-size:13px;
        line-height:1.35;
    }

    .tts-status-message {
        width:100%;
        padding:12px 14px;
        margin:0 0 18px 0;
        border:3px solid #262626;
        border-radius:5px;
        background:#FFFFFF;
        color:#262626;
        font-size:14px;
        line-height:1.4;
        text-align:center;
    }

    @media (max-width: 640px) {
        .flvm-topbar {
            flex-direction:column;
            align-items:center;
            justify-content:flex-start;
            gap:10px;
            min-height:0;
        }

        .flvm-title-block {
            flex:none;
            width:100%;
            padding:0;
            text-align:center;
        }

        .flvm-topbar h1,
        .flvm-process-id {
            text-align:center;
            margin-left:auto;
            margin-right:auto;
        }

        .flvm-actions {
            position:static;
            width:100%;
            justify-content:center;
            margin-top:0;
        }

        .video-config-row-main {
            justify-content:stretch;
        }

        .video-config-item-didactic-style,
        .video-config-item-duration {
            flex:1 1 calc(50% - 8px);
            min-width:0;
        }
    }