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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: #0a0f1e;
    min-height: 100vh;
    color: #e2e8f0;
    line-height: 1.6;
    padding: 48px 24px;
}

.container {
    max-width: 1600px;
    margin: 0 auto;
    transition: max-width 0.3s ease, padding 0.3s ease;
}

/* Header */
h1 {
    font-size: 2.5em;
    font-weight: 700;
    color: #fff;
    margin-bottom: 8px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    animation: fadeInUp 0.6s ease-out;
}

h1:hover {
    color: #6495ed;
    text-shadow: 0 0 20px rgba(100, 149, 237, 0.5);
    transform: translateX(5px);
}

.subtitle {
    color: #94a3b8;
    font-size: 1em;
    margin-bottom: 32px;
    transition: color 0.3s ease;
    animation: fadeInUp 0.6s ease-out 0.1s both;
}

/* Main Layout */
.main-layout {
    display: grid;
    grid-template-columns: 460px 1fr;
    gap: 28px;
    transition: grid-template-columns 0.4s cubic-bezier(0.4, 0, 0.2, 1), gap 0.3s ease;
}

/* Sections */
.section {
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid rgba(100, 149, 237, 0.1);
    border-radius: 12px;
    padding: 36px;
    margin-bottom: 28px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    animation: fadeInUp 0.6s ease-out backwards;
}

.section:nth-child(1) { animation-delay: 0.2s; }
.section:nth-child(2) { animation-delay: 0.26s; }
.section:nth-child(3) { animation-delay: 0.32s; }
.section:nth-child(4) { animation-delay: 0.38s; }
.section:nth-child(5) { animation-delay: 0.44s; }
.section:nth-child(6) { animation-delay: 0.5s; }

/* Sidebar tab navigation — each tab shows a stacked icon + label. An animated
   gradient pill (.tab-indicator) slides to the active tab; panels cross-fade. */
.config-sidebar {
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid rgba(100, 149, 237, 0.1);
    border-radius: 14px;
    padding: 20px 20px 24px;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.config-sidebar:hover {
    border-color: rgba(100, 149, 237, 0.28);
    box-shadow: 0 16px 44px rgba(100, 149, 237, 0.14);
}

.sidebar-tabs {
    position: relative;
    display: flex;
    gap: 4px;
    background: rgba(0, 0, 0, 0.28);
    border: 1px solid rgba(100, 149, 237, 0.08);
    border-radius: 14px;
    padding: 6px;
    margin-bottom: 22px;
}

.sidebar-tabs .tab {
    flex: 1 1 0;
    min-width: 0;
    position: relative;
    z-index: 1;
    background: transparent;
    border: none;
    color: #94a3b8;
    padding: 12px 4px 10px;
    font-size: 0.78em;
    font-weight: 600;
    letter-spacing: 0.35px;
    cursor: pointer;
    border-radius: 10px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 6px;
    transition: color 0.25s ease, transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.sidebar-tabs .tab-icon {
    width: 22px;
    height: 22px;
    color: inherit;
    transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), color 0.25s ease;
}

.sidebar-tabs .tab-label {
    line-height: 1;
    white-space: nowrap;
}

.sidebar-tabs .tab:hover {
    color: #cbd5e1;
}

.sidebar-tabs .tab:hover .tab-icon {
    transform: translateY(-1px) scale(1.05);
}

.sidebar-tabs .tab:focus-visible {
    outline: 2px solid rgba(100, 149, 237, 0.55);
    outline-offset: 2px;
}

.sidebar-tabs .tab.active {
    color: #fff;
}

.sidebar-tabs .tab.active .tab-icon {
    color: #fff;
    transform: translateY(-1px) scale(1.08);
}

.sidebar-tabs .tab-indicator {
    position: absolute;
    top: 6px;
    bottom: 6px;
    left: 0;
    width: 0;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.95), rgba(118, 75, 162, 0.9));
    border-radius: 10px;
    box-shadow: 0 6px 18px rgba(102, 126, 234, 0.38), inset 0 1px 0 rgba(255, 255, 255, 0.08);
    transition: left 0.38s cubic-bezier(0.4, 0, 0.2, 1), width 0.38s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 0;
    pointer-events: none;
}

.tab-panels {
    position: relative;
    padding: 4px 4px 4px;
    min-height: 220px;
}

.tab-panel {
    display: none;
}

.tab-panel.active {
    display: block;
    animation: tabFadeIn 0.32s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes tabFadeIn {
    from { opacity: 0; transform: translateY(-6px); }
    to   { opacity: 1; transform: translateY(0); }
}

.tab-panel .form-group:last-child { margin-bottom: 0; }

.field-hint {
    display: block;
    margin-top: 6px;
    color: #64748b;
    font-size: 0.8em;
    letter-spacing: 0.1px;
}

.pack-summary {
    margin-top: 18px;
    padding: 12px 16px;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.1), rgba(118, 75, 162, 0.08));
    border: 1px solid rgba(100, 149, 237, 0.25);
    border-radius: 10px;
    color: #cbd5e1;
    font-size: 0.9em;
    line-height: 1.5;
}

.pack-summary strong {
    color: #fff;
    font-weight: 700;
    font-size: 1.05em;
    letter-spacing: 0.3px;
}

.pack-summary .muted {
    color: #94a3b8;
    font-size: 0.92em;
}

.config-sidebar > .btn {
    margin-top: 20px;
    padding: 16px 24px;
    font-size: 1.05em;
    letter-spacing: 0.3px;
}

/* Segmented toggle (SP vs mm). Animated gradient pill slides to the active segment. */
.seg-toggle {
    position: relative;
    display: inline-flex;
    background: rgba(0, 0, 0, 0.28);
    border: 1px solid rgba(100, 149, 237, 0.1);
    border-radius: 10px;
    padding: 4px;
    margin-bottom: 18px;
    width: 100%;
}

.seg-toggle .seg {
    position: relative;
    z-index: 1;
    flex: 1 1 0;
    background: transparent;
    border: none;
    color: #94a3b8;
    padding: 9px 14px;
    font-size: 0.85em;
    font-weight: 600;
    letter-spacing: 0.25px;
    cursor: pointer;
    border-radius: 7px;
    transition: color 0.25s ease;
    white-space: nowrap;
}

.seg-toggle .seg:hover {
    color: #cbd5e1;
}

.seg-toggle .seg.active {
    color: #fff;
}

.seg-toggle .seg-indicator {
    position: absolute;
    top: 4px;
    bottom: 4px;
    left: 0;
    width: 0;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.92), rgba(118, 75, 162, 0.88));
    border-radius: 7px;
    box-shadow: 0 4px 14px rgba(102, 126, 234, 0.32);
    transition: left 0.32s cubic-bezier(0.4, 0, 0.2, 1), width 0.32s cubic-bezier(0.4, 0, 0.2, 1);
    z-index: 0;
    pointer-events: none;
}

/* Subtle divider between the cells group and the housing group inside the Cells tab. */
.panel-divider {
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(100, 149, 237, 0.22), transparent);
    margin: 18px 0 20px;
}

.preview-container {
    padding: 28px;
}

.section:hover {
    border-color: rgba(100, 149, 237, 0.4);
    box-shadow: 0 12px 40px rgba(100, 149, 237, 0.2);
    filter: brightness(1.02);
    transform: translateY(-3px);
}

.section h2 {
    color: #fff;
    font-size: 1.3em;
    margin-bottom: 20px;
    font-weight: 600;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.section:hover h2 {
    color: #6495ed;
    transform: translateX(4px) scale(1.02);
    text-shadow: 0 0 15px rgba(100, 149, 237, 0.3);
}

.section h3 {
    color: #94a3b8;
    font-size: 0.9em;
    margin-bottom: 12px;
    margin-top: 20px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    transition: color 0.2s ease;
}

.section:hover h3 {
    color: #cbd5e1;
}

/* Form Elements */
.form-group {
    margin-bottom: 20px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}

.form-group:hover {
    transform: translateX(2px) scale(1.005);
    background: rgba(100, 149, 237, 0.02);
    border-radius: 8px;
}

.form-group:has(select) {
    z-index: 100;
}

.form-group:hover {
    opacity: 1;
}

label {
    display: block;
    color: #cbd5e1;
    font-size: 0.9em;
    margin-bottom: 6px;
    font-weight: 500;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.form-group:hover label {
    color: #e2e8f0;
    filter: brightness(1.1);
    transform: scale(1.02) translateX(2px);
}

select, input[type="number"] {
    width: 100%;
    padding: 10px 12px;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(100, 149, 237, 0.2);
    border-radius: 6px;
    color: #e2e8f0;
    font-size: 0.95em;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

input[type="number"] {
    -moz-appearance: textfield;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    isolation: isolate;
}

input[type="number"]:hover {
    border-color: rgba(100, 149, 237, 0.5);
    box-shadow: 0 4px 12px rgba(100, 149, 237, 0.2);
    filter: brightness(1.05);
    transform: translateY(-1px);
}

input[type="number"]:focus {
    outline: none;
    border-color: rgba(100, 149, 237, 0.6);
    background: rgba(0, 0, 0, 0.4);
    box-shadow: 0 0 0 3px rgba(100, 149, 237, 0.1);
}

select {
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2394a3b8' d='M6 9L1 4h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 36px;
    cursor: pointer;
}

select:hover {
    border-color: rgba(100, 149, 237, 0.4);
}

select:focus {
    outline: none;
    border-color: rgba(100, 149, 237, 0.6);
    background: rgba(0, 0, 0, 0.4);
}

select option {
    background: #1e293b;
    color: #e2e8f0;
    padding: 10px;
}

.custom-select{position:relative;width:100%;isolation:isolate}
.custom-select select{display:none}
.select-selected{background:rgba(0,0,0,.3);border:1px solid rgba(100,149,237,.2);border-radius:6px;padding:10px 36px 10px 12px;color:#e2e8f0;cursor:pointer;transition:all .3s cubic-bezier(.4,0,.2,1);position:relative;user-select:none;font-size:.95em;z-index:1;isolation:isolate}
.select-selected:after{content:'';position:absolute;top:50%;right:12px;width:0;height:0;border:5px solid transparent;border-top-color:#94a3b8;transform:translateY(-30%);transition:transform .3s ease}
.select-selected.select-arrow-active:after{transform:translateY(-50%) rotate(180deg);border-top-color:#6495ed}
.select-selected:hover{border-color:rgba(100,149,237,.6);background:rgba(0,0,0,.4);box-shadow:0 4px 12px rgba(100,149,237,.2);filter:brightness(1.05);transform:translateY(-1px)}
.select-items{position:absolute;background:#1e293b;backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);border:1px solid rgba(100,149,237,.3);border-radius:8px;top:calc(100% + 4px);left:0;right:0;z-index:10000;max-height:0;overflow:hidden;opacity:0;visibility:hidden;transform:translateY(-15px) scale(0.95);transform-origin:top center;transition:max-height 0.4s cubic-bezier(0.34, 1.56, 0.64, 1),opacity 0.3s ease,transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1),visibility 0s 0.4s;box-shadow:0 10px 40px rgba(0,0,0,.5);pointer-events:none}
.select-items.show{max-height:300px;opacity:1;visibility:visible;transform:translateY(0) scale(1);overflow-y:auto;transition-delay:0s;pointer-events:auto}
.select-items div{padding:12px 16px;color:#cbd5e1;cursor:pointer;transition:all .2s ease;border-left:3px solid transparent;font-size:.95em;opacity:0;transform:translateX(-10px)}
.select-items.show div{opacity:1;transform:translateX(0)}
.select-items.show div:nth-child(1){transition-delay:.05s}
.select-items.show div:nth-child(2){transition-delay:.08s}
.select-items.show div:nth-child(3){transition-delay:.11s}
.select-items.show div:nth-child(4){transition-delay:.14s}
.select-items.show div:nth-child(5){transition-delay:.17s}
.select-items div:hover{background:rgba(100,149,237,.15);color:#fff;border-left-color:#6495ed;padding-left:20px}
.select-items div.same-as-selected{background:rgba(100,149,237,.2);color:#6495ed;font-weight:600;border-left-color:#6495ed}
.select-items::-webkit-scrollbar{width:6px}
.select-items::-webkit-scrollbar-track{background:rgba(0,0,0,.2);border-radius:3px}
.select-items::-webkit-scrollbar-thumb{background:rgba(100,149,237,.4);border-radius:3px}
.select-items::-webkit-scrollbar-thumb:hover{background:rgba(100,149,237,.6)}
.select-hide{display:none}

/* Checkbox */
.checkbox-group {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 16px;
    transition: all 0.2s ease;
}

.checkbox-group:hover {
    filter: brightness(1.1);
    transform: translateX(3px);
}

input[type="checkbox"] {
    width: 22px;
    height: 22px;
    cursor: pointer;
    position: relative;
    appearance: none;
    background: rgba(0, 0, 0, 0.3);
    border: 2px solid rgba(100, 149, 237, 0.3);
    border-radius: 6px;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    outline: none;
    overflow: hidden;
}

input[type="checkbox"]::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    transform: translate(-50%, -50%);
    transition: width 0.4s cubic-bezier(0.34, 1.56, 0.64, 1),
                height 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

input[type="checkbox"]:checked::before {
    width: 150%;
    height: 150%;
}

input[type="checkbox"]:hover {
    border-color: rgba(100, 149, 237, 0.6);
    background: rgba(100, 149, 237, 0.1);
    transform: scale(1.05);
}

input[type="checkbox"]:active {
    transform: scale(0.95);
}

input[type="checkbox"]:checked {
    border-color: #667eea;
    background: transparent;
}

input[type="checkbox"]:checked::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0);
    color: white;
    font-size: 14px;
    font-weight: bold;
    z-index: 1;
    animation: checkmarkPop 0.5s cubic-bezier(0.34, 1.56, 0.64, 1) 0.1s forwards;
}

@keyframes checkmarkPop {
    0% {
        opacity: 0;
        transform: translate(-50%, -50%) scale(0) rotate(-45deg);
    }
    50% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1.3) rotate(10deg);
    }
    100% {
        opacity: 1;
        transform: translate(-50%, -50%) scale(1) rotate(0deg);
    }
}

input[type="checkbox"]:focus {
    box-shadow: 0 0 0 3px rgba(100, 149, 237, 0.2);
}

.checkbox-group label {
    margin-bottom: 0;
    cursor: pointer;
    transition: color 0.2s ease;
}

.checkbox-group:hover label {
    color: #fff;
}

/* Button */
.btn {
    width: 100%;
    padding: 14px 24px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
    border: none;
    border-radius: 8px;
    font-size: 1em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    margin-top: 8px;
    position: relative;
    overflow: hidden;
    isolation: isolate;
}

.btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s ease;
}

.btn:hover::before {
    left: 100%;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 24px rgba(102, 126, 234, 0.4);
    filter: brightness(1.1);
    animation: pulse 2s ease-in-out infinite;
}

.btn:active {
    transform: translateY(0) scale(0.98);
    box-shadow: 0 5px 10px rgba(102, 126, 234, 0.2);
    filter: brightness(0.95);
    animation: none;
}

/* Grid Layout */
.row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin-bottom: 20px;
    transition: grid-template-columns 0.3s ease, gap 0.3s ease;
}

.row .form-group {
    margin-bottom: 0;
}

/* Preview */
.preview-container {
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid rgba(100, 149, 237, 0.1);
    border-radius: 12px;
    padding: 36px;
    height: fit-content;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    animation: fadeInUp 0.6s ease-out 0.3s backwards;
}

.preview-container:hover {
    border-color: rgba(100, 149, 237, 0.4);
    box-shadow: 0 12px 40px rgba(100, 149, 237, 0.2);
    filter: brightness(1.02);
    transform: translateY(-3px);
}

.preview-container h2 {
    margin-bottom: 20px;
    color: #fff;
    font-size: 1.3em;
    font-weight: 600;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

.preview-container:hover h2 {
    color: #6495ed;
    transform: translateX(4px) scale(1.02);
    text-shadow: 0 0 15px rgba(100, 149, 237, 0.3);
}

.preview-container.updating {
    border-color: rgba(100, 149, 237, 0.4);
}

#preview {
    width: 100%;
    height: 720px;
    border: 1px solid rgba(100, 149, 237, 0.2);
    border-radius: 10px;
    background: #1e293b;
    display: block;
    cursor: grab;
    transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

#preview:hover {
    border-color: rgba(100, 149, 237, 0.5);
}

#preview:active {
    cursor: grabbing;
}

#previewStats {
    margin-top: 12px;
    padding: 12px;
    background: rgba(0, 0, 0, 0.2);
    border-radius: 6px;
    text-align: center;
    font-size: 0.95em;
    color: #94a3b8;
    transition: all 0.3s ease;
}

#previewStats:hover {
    background: rgba(0, 0, 0, 0.3);
    color: #e2e8f0;
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(10, 15, 30, 0.95);
    backdrop-filter: blur(8px);
    display: none;
    justify-content: center;
    align-items: center;
    z-index: 9999;
    animation: fadeIn 0.3s ease;
}

.loading-overlay.active {
    display: flex;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.loading-content {
    text-align: center;
    animation: slideUp 0.4s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.spinner {
    width: 60px;
    height: 60px;
    border: 4px solid rgba(100, 149, 237, 0.2);
    border-top-color: #6495ed;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 24px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-text {
    font-size: 1.2em;
    color: #fff;
    font-weight: 600;
    margin-bottom: 8px;
}

.loading-subtext {
    font-size: 0.95em;
    color: #94a3b8;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes pulse {
    0%, 100% {
        box-shadow: 0 4px 24px rgba(100, 149, 237, 0.3);
    }
    50% {
        box-shadow: 0 4px 32px rgba(100, 149, 237, 0.5);
    }
}

@keyframes ripple {
    0% {
        transform: scale(0);
        opacity: 0.5;
    }
    100% {
        transform: scale(2);
        opacity: 0;
    }
}

/* Responsive Design */
@media (max-width: 1500px) {
    .main-layout {
        grid-template-columns: 420px 1fr;
    }
    #preview { height: 640px; }
}

@media (max-width: 1200px) {
    .main-layout {
        grid-template-columns: 1fr;
    }

    .config-sidebar {
        order: 2;
    }

    .preview-container {
        order: 1;
    }

    #preview {
        height: 520px;
    }
}

@media (max-width: 768px) {
    body {
        padding: 20px 16px;
    }

    h1 {
        font-size: 2em;
        margin-bottom: 12px;
    }

    .subtitle {
        font-size: 0.95em;
        margin-bottom: 28px;
    }

    .section {
        padding: 24px;
        margin-bottom: 20px;
    }

    .preview-container {
        padding: 24px;
    }

    .row {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    #preview {
        height: 400px;
        cursor: default;
    }

    .form-group {
        margin-bottom: 16px;
    }

    label {
        font-size: 0.9em;
        margin-bottom: 8px;
    }

    select, input[type="number"] {
        font-size: 16px;
        padding: 12px 14px;
    }

    .btn {
        padding: 14px 24px;
        font-size: 1em;
    }

    .loading-text {
        font-size: 1.1em;
    }

    .loading-subtext {
        font-size: 0.9em;
    }
}

@media (max-width: 480px) {
    body {
        padding: 16px 12px;
    }

    h1 {
        font-size: 1.75em;
    }

    .section {
        padding: 20px;
        border-radius: 10px;
    }

    .preview-container {
        padding: 20px;
    }

    .section h2 {
        font-size: 1.2em;
        margin-bottom: 20px;
    }

    .section h3 {
        font-size: 0.85em;
    }

    #preview {
        height: 350px;
    }

    .spinner {
        width: 50px;
        height: 50px;
    }
}

/* Landscape orientation for mobile */
@media (max-width: 768px) and (orientation: landscape) {
    .main-layout {
        grid-template-columns: 300px 1fr;
    }

    .config-sidebar {
        order: 1;
    }

    .preview-container {
        order: 2;
    }

    #preview {
        height: 350px;
    }
}

/* Touch device optimizations */
@media (hover: none) and (pointer: coarse) {
    select, input[type="number"], .btn {
        min-height: 48px;
        font-size: 16px;
    }

    .checkbox-group input[type="checkbox"] {
        width: 28px;
        height: 28px;
    }

    .checkbox-group label {
        padding-left: 12px;
    }

    .form-group:hover {
        transform: none;
        background: transparent;
    }

    input[type="number"]:hover,
    select:hover,
    .btn:hover {
        transform: none;
        filter: none;
    }

    .btn:active {
        transform: scale(0.97);
    }

    #preview {
        cursor: default;
        touch-action: pan-x pan-y pinch-zoom;
    }
}

/* Axis diagram — resolves width/depth confusion by showing which input maps to which
   on-screen dimension. Mirrors the canvas orientation: X horizontal, Y vertical, Z depth. */
.axis-diagram {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 8px 12px 4px;
    margin: -4px -4px 16px;
    background: rgba(0, 0, 0, 0.18);
    border: 1px solid rgba(100, 149, 237, 0.12);
    border-radius: 10px;
}

.axis-diagram svg {
    width: 100%;
    max-width: 260px;
    height: auto;
    display: block;
}

/* Busbars */
#busbarList {
    margin-bottom: 8px;
}

.busbar-empty {
    color: #94a3b8;
    font-size: 0.85em;
    font-style: italic;
    text-align: center;
    padding: 12px 8px;
    border: 1px dashed rgba(100, 149, 237, 0.2);
    border-radius: 6px;
}

.busbar-row {
    padding: 8px 10px;
    border: 1px solid rgba(100, 149, 237, 0.15);
    border-radius: 8px;
    margin-bottom: 6px;
    cursor: pointer;
    transition: all 0.2s ease;
    background: rgba(0, 0, 0, 0.2);
}

.busbar-row:hover {
    border-color: rgba(100, 149, 237, 0.35);
    background: rgba(0, 0, 0, 0.3);
}

.busbar-row.active {
    border-color: #6495ed;
    box-shadow: 0 0 0 1px rgba(100, 149, 237, 0.4), 0 4px 12px rgba(100, 149, 237, 0.15);
    background: rgba(100, 149, 237, 0.08);
}

.busbar-header {
    display: flex;
    align-items: center;
    gap: 8px;
}

.busbar-swatch {
    width: 16px;
    height: 16px;
    border-radius: 4px;
    flex-shrink: 0;
    box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.15);
}

.busbar-name {
    flex: 1;
    min-width: 0;
    padding: 4px 6px;
    background: transparent;
    border: 1px solid transparent;
    color: #e2e8f0;
    font-size: 0.9em;
    border-radius: 4px;
}

.busbar-name:hover {
    border-color: rgba(100, 149, 237, 0.25);
}

.busbar-name:focus {
    outline: none;
    border-color: rgba(100, 149, 237, 0.6);
    background: rgba(0, 0, 0, 0.3);
}

.busbar-del {
    background: none;
    border: none;
    color: #94a3b8;
    cursor: pointer;
    font-size: 1.25em;
    padding: 0 6px;
    line-height: 1;
    border-radius: 4px;
    transition: all 0.15s ease;
}

.busbar-del:hover {
    color: #ef4444;
    background: rgba(239, 68, 68, 0.15);
}

.busbar-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    margin-top: 6px;
    padding-left: 24px;
    font-size: 0.8em;
    color: #94a3b8;
}

.busbar-thickness-label {
    display: flex;
    align-items: center;
    gap: 6px;
    color: #94a3b8;
    font-size: 0.95em;
    cursor: text;
}

.busbar-thickness {
    width: 64px;
    padding: 3px 6px;
    font-size: 0.9em;
    background: rgba(0, 0, 0, 0.3);
    border: 1px solid rgba(100, 149, 237, 0.2);
    border-radius: 4px;
    color: #e2e8f0;
}

.busbar-thickness:focus {
    outline: none;
    border-color: rgba(100, 149, 237, 0.6);
}

.busbar-blocked {
    margin-top: 6px;
    padding: 6px 8px;
    font-size: 0.8em;
    color: #ef4444;
    background: rgba(239, 68, 68, 0.08);
    border-radius: 4px;
}

.btn-secondary {
    width: 100%;
    padding: 10px 16px;
    background: rgba(100, 149, 237, 0.12);
    border: 1px solid rgba(100, 149, 237, 0.3);
    color: #e2e8f0;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.9em;
    font-weight: 500;
    transition: all 0.2s ease;
    margin-bottom: 12px;
}

.btn-secondary:hover {
    background: rgba(100, 149, 237, 0.22);
    border-color: rgba(100, 149, 237, 0.5);
    transform: translateY(-1px);
}

.btn-secondary:active {
    transform: translateY(0);
}