.tool-fullwidth {
    width: 100%;
    max-width: 100%;
    margin: 0;
    padding: 0;
}

/* Tool shell */
.text-tool {
    max-width: 100%;
    margin: 0 auto;
}

.text-tool.editor-section,
.editor-section.text-tool {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.text-tool .card:not(.result-card) {
    border: 1px solid var(--color-border, #e5e7eb);
    box-shadow: var(--shadow-sm, 0 1px 3px rgba(0, 0, 0, 0.06));
    border-radius: var(--radius, 12px);
    background: var(--color-surface, #fff);
}

.text-tool .card-body {
    padding: 1.25rem 1.35rem;
}

.text-tool .card-title {
    color: var(--color-text, #1f2937);
    font-weight: 700;
    font-size: 1.05rem;
}

.text-tool .form-control,
.text-tool .form-select,
.text-tool .select-input,
.text-tool textarea {
    border-radius: 8px;
    border: 1px solid var(--color-border, #e5e7eb);
}

.text-tool .form-control:focus,
.text-tool .form-select:focus,
.text-tool textarea:focus {
    border-color: var(--color-primary, #0d9488);
    box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
}

.text-tool .btn-primary {
    background: var(--color-primary, #0d9488);
    border-color: var(--color-primary, #0d9488);
}

.text-tool .btn-primary:hover {
    background: var(--color-primary-hover, #0f766e);
    border-color: var(--color-primary-hover, #0f766e);
}

.text-tool .alert {
    border-radius: 10px;
}

[data-theme="dark"] .text-tool .card:not(.result-card) {
    background: var(--color-surface, #1f2937);
    border-color: var(--color-border, #374151);
}

[data-theme="dark"] .text-tool .card-title,
[data-theme="dark"] .text-tool .form-label,
[data-theme="dark"] .text-tool {
    color: var(--color-text, #f9fafb);
}

[data-theme="dark"] .text-tool .text-muted,
[data-theme="dark"] .text-tool .form-text {
    color: var(--color-text-secondary, #9ca3af) !important;
}

[data-theme="dark"] .text-tool .form-control,
[data-theme="dark"] .text-tool .form-select,
[data-theme="dark"] .text-tool textarea {
    background: #111827;
    color: var(--color-text, #f9fafb);
    border-color: var(--color-border, #374151);
}

/* --- tool: utf8-conversion --- */
.utf8-converter {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.utf8-converter .btn-primary {
    background: #6c63ff;
    border: none;
}

.utf8-converter .btn-primary:hover {
    background: #2574e6;
}

.utf8-converter .btn-outline-secondary {
    border-color: #6c63ff;
    color: #6c63ff;
}

.utf8-converter .btn-outline-secondary:hover {
    background: #6c63ff;
    color: #fff;
}

.utf8-converter .form-label {
    font-weight: 500;
    color: #555;
    margin-bottom: 0.5rem;
}

.utf8-converter .form-control {
    border: 1px solid #e9ecef;
    border-radius: 6px;
}

.utf8-converter .form-control:focus {
    border-color: #6c63ff;
    box-shadow: 0 0 0 0.2rem rgba(108, 99, 255, 0.25);
}

.utf8-converter .nav-tabs .nav-link {
    color: #6c63ff;
    border: none;
    border-bottom: 2px solid transparent;
}

.utf8-converter .nav-tabs .nav-link.active {
    color: #6c63ff;
    background: none;
    border-bottom: 2px solid #6c63ff;
}

.utf8-converter .nav-tabs .nav-link:hover {
    border-color: transparent;
    border-bottom: 2px solid #6c63ff;
}

.utf8-converter .result-box {
    background: #f8f9fa;
    border: 1px solid #e9ecef;
    border-radius: 8px;
    padding: 1.5rem;
    margin-top: 1rem;
}

.utf8-converter .result-box .form-control {
    background: #fff;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

.utf8-converter .encoding-info {
    background: #e3f2fd;
    border-left: 4px solid #2196f3;
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1rem;
}

.utf8-converter .copy-btn {
    position: absolute;
    top: 0.5rem;
    right: 0.5rem;
    z-index: 10;
}

.utf8-converter .input-group {
    position: relative;
}

.utf8-converter .alert {
    border-radius: 6px;
    border: none;
}

.utf8-converter .alert-danger {
    background: #f8d7da;
    color: #721c24;
}

.utf8-converter .alert-success {
    background: #d4edda;
    color: #155724;
}