/* ============================================
   Shaft Design & Analysis Tool CSS
   ============================================ */

html {
    scrollbar-gutter: stable;
}

/* Page Layout */
.shaft-app {
    min-height: 100vh;
    background: var(--color-bg-primary);
}

.shaft-app-header {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--color-border);
    padding: 0.75rem 1.5rem;
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.shaft-app-header .back-link {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--color-text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.2s ease;
    padding: 0.5rem 1rem;
    border-radius: 8px;
}

.shaft-app-header .back-link:hover {
    color: var(--color-accent);
    background: var(--color-bg-tertiary);
}

.shaft-app-header .back-link svg {
    width: 18px;
    height: 18px;
    transition: transform 0.2s ease;
}

.shaft-app-header .back-link:hover svg {
    transform: translateX(-3px);
}

.shaft-app-title {
    font-family: var(--font-heading);
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-text-primary);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.shaft-app-title .title-icon {
    font-size: 1.3rem;
}

.shaft-app-actions {
    display: flex;
    gap: 0.5rem;
}

/* Main Layout Container */
.shaft-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    width: 100%;
}

/* Main Grid Layout */
.shaft-main-grid {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    width: 100%;
}

.grid-col-left {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    width: 100%;
}

.grid-col-middle {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    width: 100%;
}

.grid-col-right {
    display: flex;
    flex-direction: column;
    gap: 1.2rem;
    width: 100%;
}

.panel-section {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 10px;
    padding: 1.25rem 1.5rem;
    box-shadow: var(--shadow-sm);
}

.panel-section-title {
    font-family: var(--font-heading);
    font-size: 0.8rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-text-muted);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.panel-section-title .section-icon {
    font-size: 1rem;
}

/* Add support/load buttons */
.add-btn {
    background: var(--color-bg-tertiary);
    border: 1.5px solid var(--color-border);
    color: var(--color-text-primary);
    border-radius: 6px;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-weight: 700;
    font-size: 1rem;
    line-height: 1;
    transition: all 0.2s ease;
}

.add-btn:hover {
    border-color: var(--color-accent);
    background: var(--color-accent);
    color: #ffffff;
}

/* Elements lists */
.elements-list-box {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.shaft-list-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0.75rem;
    background: var(--color-bg-tertiary);
    border: 1px solid var(--color-border-light);
    border-radius: 8px;
    font-size: 0.82rem;
}

.list-item-info {
    display: flex;
    flex-direction: column;
    gap: 0.15rem;
}

.list-item-title {
    font-weight: 600;
    color: var(--color-text-primary);
}

.list-item-subtitle {
    font-size: 0.7rem;
    color: var(--color-text-muted);
    font-family: var(--font-mono);
}

.list-item-actions {
    display: flex;
    gap: 0.35rem;
}

.list-btn {
    background: transparent;
    border: none;
    cursor: pointer;
    font-size: 0.9rem;
    padding: 0.2rem;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s ease;
}

.list-btn:hover {
    background: var(--color-bg-elevated);
}

.list-btn.delete:hover {
    color: var(--color-accent);
}

/* Form inputs & rows */
.prop-row {
    display: flex;
    gap: 0.75rem;
    margin-bottom: 0.75rem;
}

.prop-group {
    flex: 1;
}

.prop-label {
    display: block;
    font-size: 0.78rem;
    font-weight: 600;
    color: var(--color-text-secondary);
    margin-bottom: 0.3rem;
}

.prop-input {
    width: 100%;
    padding: 0.5rem 0.65rem;
    background: var(--color-bg-tertiary);
    border: 1.5px solid var(--color-border);
    border-radius: 8px;
    color: var(--color-text-primary);
    font-family: var(--font-mono);
    font-size: 0.88rem;
    transition: all 0.2s ease;
}

.prop-input:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.1);
    background: var(--color-bg-secondary);
}

.prop-select {
    width: 100%;
    padding: 0.5rem 0.65rem;
    background: var(--color-bg-tertiary);
    border: 1.5px solid var(--color-border);
    border-radius: 8px;
    color: var(--color-text-primary);
    font-family: var(--font-body);
    font-size: 0.88rem;
    cursor: pointer;
    transition: all 0.2s ease;
}

.prop-select:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(220, 38, 38, 0.1);
}

.shaft-btn-secondary {
    background: var(--color-bg-tertiary);
    border: 1.5px solid var(--color-border);
    color: var(--color-text-secondary);
    border-radius: 8px;
    cursor: pointer;
    font-family: var(--font-heading);
    font-weight: 600;
    transition: all 0.2s ease;
}

.shaft-btn-secondary:hover {
    border-color: var(--color-accent);
    background: var(--color-bg-elevated);
    color: var(--color-accent);
}

/* Range Slider */
input[type="range"] {
    -webkit-appearance: none;
    width: 100%;
    height: 6px;
    border-radius: 3px;
    background: var(--color-border);
    outline: none;
    cursor: pointer;
}

input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--color-accent);
    cursor: pointer;
    transition: transform 0.1s ease;
}

input[type="range"]::-webkit-slider-thumb:hover {
    transform: scale(1.2);
}

/* Reference Diagram Container */
.diagram-container {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 16px;
    padding: 1.5rem;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.05);
    transition: all 0.3s ease;
    margin-bottom: 1.2rem;
}

.diagram-container:hover {
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
}

.diagram-title {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--color-text-primary);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.diagram-title .dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    display: inline-block;
}

.diagram-title .dot.red { background: #dc2626; }

.diagram-svg-wrap {
    width: 100%;
    display: block;
    border-radius: 8px;
    background: var(--color-bg-primary);
    border: 1px solid var(--color-border-light);
    overflow: hidden;
}

/* Interactive SVG Cursors */
.draggable {
    cursor: grab;
    pointer-events: all;
}
.draggable:hover {
    filter: brightness(1.2);
}
.dragging {
    cursor: grabbing;
}

/* Status/Info Bar */
.status-bar {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0.5rem 1rem;
    background: var(--color-bg-tertiary);
    border-radius: 8px;
    font-size: 0.78rem;
    color: var(--color-text-muted);
}

.status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #059669;
    animation: pulse-dot 2s ease-in-out infinite;
}

@keyframes pulse-dot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.4; }
}

.status-info {
    display: flex;
    gap: 1rem;
    margin-left: auto;
}

.status-info span {
    font-family: var(--font-mono);
    font-size: 0.72rem;
}

/* Strength calculations cards */
.results-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.6rem;
}

.result-card {
    padding: 0.75rem;
    background: linear-gradient(135deg, var(--color-bg-tertiary), var(--color-bg-primary));
    border: 1.5px solid var(--color-border-light);
    border-radius: 10px;
    text-align: center;
    transition: all 0.3s ease;
}

.result-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.result-title {
    font-size: 0.72rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    margin-bottom: 0.25rem;
}

.result-value {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--color-accent);
    font-family: var(--font-mono);
}

.result-subtitle {
    font-size: 0.68rem;
    color: var(--color-text-muted);
    margin-top: 0.15rem;
}

/* Popover editor */
.shaft-popover {
    position: absolute;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(16px);
    border: 1px solid rgba(0, 0, 0, 0.15);
    border-radius: 12px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
    width: 250px;
    padding: 0.75rem 1rem;
    color: #374151;
    font-family: var(--font-body);
}

.popover-arrow {
    position: absolute;
    width: 0;
    height: 0;
    border-style: solid;
}

/* Arrow facing down */
.shaft-popover[data-popper-placement^='top'] .popover-arrow {
    bottom: -8px;
    left: calc(50% - 8px);
    border-width: 8px 8px 0 8px;
    border-color: rgba(255, 255, 255, 0.9) transparent transparent transparent;
}

/* Arrow facing up */
.shaft-popover[data-popper-placement^='bottom'] .popover-arrow {
    top: -8px;
    left: calc(50% - 8px);
    border-width: 0 8px 8px 8px;
    border-color: transparent transparent rgba(255, 255, 255, 0.9) transparent;
}

.popover-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
    padding-bottom: 0.35rem;
    margin-bottom: 0.5rem;
}

.popover-title {
    font-size: 0.82rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.popover-close {
    background: transparent;
    border: none;
    font-size: 1.1rem;
    cursor: pointer;
    color: #9ca3af;
    line-height: 1;
}

.popover-close:hover {
    color: var(--color-accent);
}

.popover-body {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

/* Dark Mode Popover Overrides */
body.dark-mode .shaft-popover {
    background: rgba(30, 41, 59, 0.9);
    border-color: rgba(255, 255, 255, 0.1);
    color: #f3f4f6;
}

body.dark-mode .shaft-popover[data-popper-placement^='top'] .popover-arrow {
    border-color: rgba(30, 41, 59, 0.9) transparent transparent transparent;
}

body.dark-mode .shaft-popover[data-popper-placement^='bottom'] .popover-arrow {
    border-color: transparent transparent rgba(30, 41, 59, 0.9) transparent;
}

/* Engineering Theory Card */
.info-card {
    background: var(--color-bg-secondary);
    border: 1px solid var(--color-border);
    border-radius: 10px;
    padding: 1.25rem 1.5rem;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    gap: 0.6rem;
    margin-top: 1rem;
}

.info-card-title {
    font-family: var(--font-heading);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--color-text-primary);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-bottom: 1.5px solid var(--color-border-light);
    padding-bottom: 0.5rem;
    margin-bottom: 0.25rem;
}

.info-card-text {
    font-size: 0.74rem;
    color: var(--color-text-secondary);
    line-height: 1.4;
}

.info-formula {
    background: var(--color-bg-tertiary);
    padding: 0.4rem;
    border-radius: 5px;
    text-align: center;
    border-left: 3px solid var(--color-accent);
    overflow-x: auto;
    color: var(--color-accent);
}

.info-formula .katex-display {
    margin: 0.2rem 0;
}

/* Symmetrical Columns Desktop Layout */
@media (min-width: 1280px) {
    .shaft-container {
        max-width: 1600px;
    }
    .shaft-main-grid {
        display: grid;
        grid-template-columns: 1fr 820px 1fr;
        gap: 1.5rem;
    }
    .grid-col-left {
        display: flex;
        order: 0;
    }
    .grid-col-middle {
        order: 0;
    }
    .grid-col-right {
        display: flex;
        order: 0;
    }
}

/* Mobile/Tablet Column Stacking Order */
@media (max-width: 1279px) {
    .grid-col-middle {
        order: 1;
    }
    .grid-col-left {
        order: 2;
    }
    .grid-col-right {
        order: 3;
    }
}

/* Dark Mode Overrides */
body.dark-mode .shaft-app-header {
    background: rgba(15, 15, 20, 0.9);
}

body.dark-mode .result-card {
    background: linear-gradient(135deg, var(--color-bg-tertiary), var(--color-bg-secondary));
}

/* Force KaTeX formulas to render in theme's red accent color */
.katex, .katex-display {
    color: var(--color-accent) !important;
}