:root {
    --panel-bg: #f8f9fa;
    --border-color: #dee2e6;
    --text-color: #212529;
    --primary-color: #007bff;
    --secondary-color: #6c757d;
    --white: #fff;
    --transparent-bg-color: #eee;
    --danger-color: #C12C21;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: var(--white);
    color: var(--text-color);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    display: flex;
    width: 100%;
    max-width: 1600px;
    min-height: 90vh;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    overflow: hidden;
}

#settings-panel {
    width: 400px;
    min-width: 380px;
    background-color: var(--panel-bg);
    padding: 25px;
    overflow-y: auto;
    border-right: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
}

#settings-panel h2 {
    text-align: center;
    margin-bottom: 24px;
    font-weight: 600;
    color: #343a40;
}

fieldset {
    border: 1px solid var(--border-color);
    padding: 15px 20px;
    border-radius: 6px;
    margin-bottom: 20px;
}

legend {
    font-weight: 500;
    padding: 0 10px;
    font-size: 15px;
}

.control-group {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    margin-bottom: 15px;
    gap: 15px;
}
.control-group.stacked {
    grid-template-columns: 1fr;
    gap: 8px;
}
.control-group.stacked input {
    grid-column: 1 / 2;
}

.control-group label {
    font-size: 14px;
    color: #495057;
}

.control-group input[type="text"],
#trademark-desc {
    padding: 8px 10px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 14px;
    transition: border-color 0.2s, box-shadow 0.2s;
}
.control-group.stacked input[type="text"] {
    grid-column: auto;
}

.control-group input[type="text"]:focus,
#trademark-desc:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 2px rgba(0, 123, 255, 0.25);
}

.control-group input[type="color"] {
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
    width: 36px;
    height: 36px;
    background-color: transparent;
    border: 1px solid var(--border-color);
    cursor: pointer;
    border-radius: 50%;
    padding: 0;
}

.control-group input[type="color"]::-webkit-color-swatch {
    border-radius: 50%;
    border: none;
}

.control-group input[type="range"] {
    grid-column: 1 / 3;
    width: 100%;
}

.control-group span {
    text-align: right;
    font-size: 14px;
    min-width: 35px;
    font-family: monospace;
}

.selected-display {
    background-color: #e9ecef;
    padding: 10px;
    border-radius: 4px;
    font-size: 13px;
    margin-bottom: 10px;
    line-height: 1.6;
    color: #495057;
    min-height: 40px;
}

#trademark-desc {
    width: 100%;
    font-size: 13px;
    line-height: 1.6;
    resize: vertical;
}

.checklist-item {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    margin-bottom: 12px;
}
.checklist-item:last-child {
    margin-bottom: 0;
}
.checklist-item input[type="checkbox"] {
    margin-top: 3px;
    flex-shrink: 0;
}
.checklist-item label {
    font-size: 13px;
    line-height: 1.5;
    color: #495057;
    cursor: pointer;
}


.export-note {
    padding: 12px;
    background-color: #e9ecef;
    border-radius: 6px;
    margin-bottom: 15px;
    font-size: 14px;
    text-align: center;
    line-height: 1.5;
}

#generate-btn {
    padding: 12px 20px;
    font-size: 16px;
    font-weight: 600;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.2s ease, opacity 0.2s ease, transform 0.1s ease;
    background-color: var(--danger-color);
    color: var(--white);
    margin-top: auto;
}

#generate-btn:hover {
    background-color: #a5251c;
}

#generate-btn:active {
    transform: translateY(1px);
}

#generate-btn:disabled {
    background-color: var(--secondary-color);
    cursor: not-allowed;
    opacity: 0.7;
}

.secondary-btn {
    width: 100%;
    padding: 10px;
    font-size: 14px;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.1s ease;
    background-color: var(--white);
    color: var(--text-color);
    border: 1px solid var(--border-color);
}

.secondary-btn:hover {
    background-color: #e9ecef;
}

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

#reset-btn {
    margin-top: 10px;
}

/* Preview Area */
#preview-area {
    flex-grow: 1;
    display: grid;
    place-items: center;
    padding: 20px;
    background-color: var(--white);
    background-image:
        linear-gradient(45deg, var(--transparent-bg-color) 25%, transparent 25%),
        linear-gradient(-45deg, var(--transparent-bg-color) 25%, transparent 25%),
        linear-gradient(45deg, transparent 75%, var(--transparent-bg-color) 75%),
        linear-gradient(-45deg, transparent 75%, var(--transparent-bg-color) 75%);
    background-size: 24px 24px;
    background-position: 0 0, 0 12px, 12px -12px, -12px 0px;
}

#logo-text {
    font-family: "阿里妈妈东方大楷 Regular", sans-serif;
    line-height: 1;
}

/* Modal Styles */
.modal-backdrop {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
}

.modal-backdrop.visible {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--white);
    border-radius: 8px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
    width: 90%;
    max-width: 700px;
    display: flex;
    flex-direction: column;
    max-height: 85vh;
    transform: scale(0.95);
    transition: transform 0.3s;
}
.modal-content.wide {
    max-width: 1200px;
}

.modal-backdrop.visible .modal-content {
    transform: scale(1);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    border-bottom: 1px solid var(--border-color);
}

.close-btn {
    background: none;
    border: none;
    font-size: 28px;
    cursor: pointer;
    line-height: 1;
}

.modal-body {
    padding: 20px;
    overflow-y: auto;
}

#class-search-input {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 15px;
}

#class-list-container {
    display: flex;
    flex-direction: column;
    gap: 5px;
}

.class-group details {
    border: 1px solid #e0e0e0;
    border-radius: 4px;
    margin-bottom: 5px;
}

.class-group summary {
    padding: 12px 15px;
    font-weight: 500;
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
    background-color: #f7f7f7;
}

.class-group summary::-webkit-details-marker {
    display: none;
}

.class-group summary:after {
    content: '▼';
    font-size: 12px;
    transition: transform 0.2s;
}

.class-group details[open] summary:after {
    transform: rotate(180deg);
}

.subgroup-list {
    padding: 10px 15px 15px 35px;
    border-top: 1px solid #e0e0e0;
    background-color: #fff;
}

.subgroup-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 0;
}

.subgroup-item label {
    font-size: 14px;
    cursor: pointer;
}

.modal-footer {
    padding: 15px 20px;
    border-top: 1px solid var(--border-color);
    text-align: right;
    background-color: #f8f9fa;
}

#modal-confirm-btn, #modal-download-btn {
    padding: 10px 20px;
    font-weight: 500;
    background-color: var(--primary-color);
    color: var(--white);
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.2s;
}

#modal-confirm-btn:hover, #modal-download-btn:hover {
    background-color: #0056b3;
}

#preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
}
.preview-item {
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 15px;
    display: flex;
    flex-direction: column;
}
.preview-item h4 {
    margin-bottom: 10px;
    text-align: center;
    font-weight: 500;
}
.preview-box {
    flex-grow: 1;
    background-color: #f1f3f5;
    border-radius: 4px;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 10px;
    min-height: 200px;
    overflow: hidden;
}
.preview-box img, .preview-box iframe {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    border: none;
}


@media (max-width: 900px) {
    .container {
        flex-direction: column;
        min-height: 95vh;
        height: auto;
    }
    #settings-panel {
        width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--border-color);
        height: auto;
        min-width: unset;
    }
    .modal-content.wide {
        max-width: 95vw;
    }
}