/* === Floating Calculator Widget === */
/* Prefix: wcalc-  (isolated from project styles) */

/* ---------- Core ---------- */
.wcalc-panel,
.wcalc-restore,
.wcalc-fab,
.wcalc-sheet,
.wcalc-backdrop {
    font-family: var(--font-main, "Segoe UI", system-ui, sans-serif);
    box-sizing: border-box;
}

/* ---------- Desktop Panel ---------- */
.wcalc-panel {
    position: fixed;
    z-index: 9998;
    width: 260px;
    background: var(--bg-surface, rgba(255,255,255,0.72));
    border: 1px solid var(--border, rgba(90,82,224,0.10));
    border-radius: var(--radius, 14px);
    box-shadow: var(--shadow-lg, 0 12px 48px rgba(0,0,0,0.10));
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: top 0.3s cubic-bezier(0.25, 0.8, 0.25, 1),
                left 0.3s cubic-bezier(0.25, 0.8, 0.25, 1),
                right 0.3s cubic-bezier(0.25, 0.8, 0.25, 1),
                transform 0.3s cubic-bezier(0.25, 0.8, 0.25, 1),
                height 0.3s cubic-bezier(0.25, 0.8, 0.25, 1),
                opacity 0.25s ease,
                box-shadow 0.3s ease;
    will-change: transform, left, top;
    contain: layout style paint;
    /* Glassmorphism */
    backdrop-filter: blur(16px) saturate(1.2);
    -webkit-backdrop-filter: blur(16px) saturate(1.2);
}

.wcalc-panel:hover {
    box-shadow: var(--shadow-hover, 0 8px 32px rgba(0,0,0,0.12)),
                0 0 0 1px rgba(90,82,224,0.08);
}

.wcalc-panel--hidden {
    display: none !important;
}

.wcalc-panel--collapsed .wcalc-body {
    display: none;
}

.wcalc-panel--collapsed {
    height: auto;
}

.wcalc-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 10px;
    background: linear-gradient(135deg, var(--primary, #5a52e0) 0%, var(--primary-mid, #4840cc) 100%);
    color: #fff;
    cursor: grab;
    user-select: none;
    border-radius: var(--radius, 14px) var(--radius, 14px) 0 0;
    position: relative;
    overflow: hidden;
}

.wcalc-header::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(255,255,255,0.12) 0%, transparent 60%);
    pointer-events: none;
}

.wcalc-header:active {
    cursor: grabbing;
}

.wcalc-header__title {
    font-size: 0.9rem;
    font-weight: 600;
    pointer-events: none;
    position: relative;
    z-index: 1;
}

.wcalc-header__controls {
    display: flex;
    gap: 4px;
    position: relative;
    z-index: 1;
}

.wcalc-header__btn {
    width: 28px;
    height: 28px;
    border: none;
    border-radius: 6px;
    background: rgba(255,255,255,0.2);
    color: #fff;
    font-size: 16px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: background 0.2s, transform 0.15s;
    position: relative;
    overflow: hidden;
}

.wcalc-header__btn:hover {
    background: rgba(255,255,255,0.35);
    transform: scale(1.08);
}

.wcalc-header__btn:focus-visible {
    outline: 2px solid rgba(255,255,255,0.8);
    outline-offset: 2px;
}

.wcalc-header__btn:active {
    transform: scale(0.95);
}

.wcalc-body {
    display: flex;
    flex-direction: column;
    padding: 8px;
    gap: 6px;
}

.wcalc-display {
    background: rgba(0,0,0,0.04);
    border-radius: var(--radius-sm, 8px);
    padding: 8px 10px;
    font-size: 1.35rem;
    font-weight: 600;
    text-align: right;
    color: var(--text-main, #1a1a2e);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    min-height: 2.4rem;
    line-height: 1.2;
    font-variant-numeric: tabular-nums;
    letter-spacing: -0.02em;
    transition: color 0.2s ease, background 0.2s ease;
    cursor: pointer;
    user-select: text;
}

.wcalc-display:active,
.wcalc-display:focus-visible {
    background: rgba(90,82,224,0.06);
}

.wcalc-display--copied {
    background: rgba(var(--accent-rgb), 0.12) !important;
    color: var(--accent, #00b8d4);
}

.wcalc-subdisplay {
    font-size: 1.05rem;
    font-weight: 500;
    color: var(--text-muted, #6a6a88);
    text-align: right;
    min-height: 1.2rem;
    padding: 0 4px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    transition: color 0.2s ease;
}

.wcalc-history-toggle {
    display: flex;
    align-items: center;
    justify-content: space-between;
    font-size: 0.75rem;
    color: var(--text-muted, #6a6a88);
    cursor: pointer;
    padding: 2px 4px;
    border-radius: 4px;
    transition: background 0.2s, color 0.2s;
}

.wcalc-history-toggle__controls {
    display: flex;
    align-items: center;
    gap: 8px;
}

.wcalc-history-clear {
    width: 28px;
    height: 28px;
    border: none;
    border-radius: 4px;
    background: transparent;
    color: var(--text-muted, #6a6a88);
    font-size: 14px;
    line-height: 1;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 0;
    transition: background 0.15s, color 0.15s;
}

.wcalc-history-clear:hover {
    background: rgba(90,82,224,0.08);
    color: var(--primary, #5a52e0);
}

.wcalc-history-clear:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 1px;
    border-radius: 4px;
}

.wcalc-history-toggle:hover {
    background: rgba(0,0,0,0.03);
    color: var(--text-secondary, #4a4a68);
}

.wcalc-history-toggle:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 2px;
    border-radius: 4px;
}

.wcalc-history {
    display: none;
    max-height: 90px;
    overflow-y: auto;
    font-size: 0.72rem;
    color: var(--text-secondary, #4a4a68);
    line-height: 1.4;
    padding: 4px 6px;
    background: rgba(0,0,0,0.02);
    border-radius: var(--radius-sm, 8px);
    scrollbar-width: thin;
}

.wcalc-history::-webkit-scrollbar {
    width: 4px;
}

.wcalc-history::-webkit-scrollbar-thumb {
    background: var(--border, rgba(90,82,224,0.15));
    border-radius: 2px;
}

.wcalc-history--visible {
    display: block;
}

.wcalc-history__item {
    display: flex;
    justify-content: space-between;
    gap: 6px;
}

.wcalc-history__expr {
    opacity: 0.8;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.wcalc-history__res {
    font-weight: 600;
    white-space: nowrap;
}

/* ---------- Keypad ---------- */
.wcalc-keypad {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 5px;
}

.wcalc-btn {
    border: none;
    border-radius: var(--radius-sm, 8px);
    padding: 10px 0;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    background: var(--bg-surface, rgba(255,255,255,0.72));
    color: var(--text-main, #1a1a2e);
    transition: background 0.15s, transform 0.08s, box-shadow 0.15s;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
    position: relative;
    overflow: hidden;
}

/* Ripple effect */
.wcalc-btn::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(90,82,224,0.12);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: width 0.3s ease, height 0.3s ease, opacity 0.3s ease;
    opacity: 0;
    pointer-events: none;
}

.wcalc-btn:active::after {
    width: 120%;
    height: 120%;
    opacity: 1;
    transition: width 0.1s ease, height 0.1s ease, opacity 0.1s ease;
}

.wcalc-btn:hover {
    background: var(--bg-surface-hover, rgba(255,255,255,0.88));
    box-shadow: 0 2px 8px rgba(0,0,0,0.06);
}

.wcalc-btn:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 2px;
    box-shadow: 0 0 0 4px rgba(90,82,224,0.12);
}

.wcalc-btn:active {
    transform: scale(0.94);
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.08);
}

.wcalc-btn--op {
    background: var(--primary, #5a52e0);
    color: #fff;
}

.wcalc-btn--op::after {
    background: rgba(255,255,255,0.18);
}

.wcalc-btn--op:hover {
    background: var(--primary-mid, #4840cc);
    box-shadow: 0 2px 12px rgba(90,82,224,0.25);
}

.wcalc-btn--eq {
    background: var(--accent, #00b8d4);
    color: var(--text-on-accent, #0b0b1a);
}

.wcalc-btn--eq::after {
    background: rgba(255,255,255,0.22);
}

.wcalc-btn--eq:hover {
    background: var(--accent-hover, #009db5);
    box-shadow: 0 2px 12px rgba(var(--accent-rgb), 0.25);
}

.wcalc-btn--fn {
    background: var(--bg-card-hover, #eef0fa);
    color: var(--text-secondary, #4a4a68);
    font-size: 0.85rem;
}

.wcalc-btn--fn::after {
    background: rgba(90,82,224,0.06);
}

.wcalc-btn--fn:hover {
    background: var(--bg-base, #e4e6f4);
}

.wcalc-btn--wide {
    grid-column: span 2;
}

/* ---------- Memory indicator ---------- */
.wcalc-memory-badge {
    font-size: 0.65rem;
    color: var(--primary, #5a52e0);
    font-weight: 700;
    opacity: 0;
    transition: opacity 0.2s, transform 0.2s;
    margin-left: 4px;
    transform: scale(0.8);
}

.wcalc-memory-badge--active {
    opacity: 1;
    transform: scale(1);
}

/* ---------- Desktop Restore Tab ---------- */
.wcalc-restore {
    position: fixed;
    z-index: 9999;
    top: 50%;
    transform: translateY(-50%) translateX(-100%);
    width: 36px;
    height: 44px;
    background: linear-gradient(135deg, var(--primary, #5a52e0) 0%, var(--primary-mid, #4840cc) 100%);
    color: #fff;
    border-radius: 0 var(--radius, 14px) var(--radius, 14px) 0;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    cursor: pointer;
    box-shadow: var(--shadow-md, 0 4px 24px rgba(0,0,0,0.08));
    transition: background 0.2s, transform 0.35s cubic-bezier(0.25, 0.8, 0.25, 1), opacity 0.3s ease;
    opacity: 0;
    overflow: hidden;
}

.wcalc-restore::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(255,255,255,0.12) 0%, transparent 60%);
    pointer-events: none;
}

.wcalc-restore:hover {
    background: linear-gradient(135deg, var(--primary-light, #6c63ff) 0%, var(--primary, #5a52e0) 100%);
    transform: translateY(-50%) translateX(0) scale(1.05);
}

.wcalc-restore:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 3px;
}

.wcalc-restore--visible {
    display: flex;
    opacity: 1;
    transform: translateY(-50%) translateX(0);
}

.wcalc-restore--left {
    left: 0;
    border-radius: 0 var(--radius, 14px) var(--radius, 14px) 0;
}

.wcalc-restore--right {
    right: 0;
    border-radius: var(--radius, 14px) 0 0 var(--radius, 14px);
    transform: translateY(-50%) translateX(100%);
}

.wcalc-restore--right.wcalc-restore--visible {
    transform: translateY(-50%) translateX(0);
}

.wcalc-restore--center {
    left: 50%;
    transform: translate(-50%, -50%) scale(0.8);
    border-radius: var(--radius, 14px);
}

.wcalc-restore--center.wcalc-restore--visible {
    transform: translate(-50%, -50%) scale(1);
}

.wcalc-restore--center:hover {
    transform: translate(-50%, -50%) scale(1.08);
}

/* ---------- Mobile FAB ---------- */
.wcalc-fab {
    position: fixed;
    z-index: 9999;
    bottom: max(20px, env(safe-area-inset-bottom));
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary, #5a52e0) 0%, var(--primary-mid, #4840cc) 100%);
    color: #fff;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.6rem;
    cursor: pointer;
    box-shadow: 0 4px 20px rgba(90,82,224,0.35), 0 0 0 1px rgba(255,255,255,0.1);
    border: 2px solid rgba(255,255,255,0.25);
    transition: transform 0.2s cubic-bezier(0.25, 0.8, 0.25, 1),
                box-shadow 0.3s ease,
                background 0.2s;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
    overflow: hidden;
}

.wcalc-fab::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(255,255,255,0.15) 0%, transparent 60%);
    pointer-events: none;
}

.wcalc-fab:hover {
    box-shadow: 0 6px 28px rgba(90,82,224,0.45), 0 0 0 2px rgba(255,255,255,0.15);
    transform: scale(1.06);
}

.wcalc-fab:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 3px;
    box-shadow: 0 0 0 6px rgba(90,82,224,0.15);
}

.wcalc-fab:active {
    transform: scale(0.92);
    box-shadow: 0 2px 12px rgba(90,82,224,0.25);
}

.wcalc-fab--left {
    left: 20px;
}

.wcalc-fab--center {
    left: 50%;
    transform: translateX(-50%);
}

.wcalc-fab--center:hover {
    transform: translateX(-50%) scale(1.06);
}

.wcalc-fab--right {
    right: 20px;
}

/* ---------- Backdrop (behind mobile sheet) ---------- */
.wcalc-backdrop {
    position: fixed;
    z-index: 9997;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0);
    pointer-events: none;
    transition: background 0.4s ease;
    touch-action: none;
}

.wcalc-backdrop--visible {
    background: rgba(0,0,0,0.35);
    pointer-events: auto;
    backdrop-filter: blur(2px);
    -webkit-backdrop-filter: blur(2px);
}

/* ---------- Mobile Bottom Sheet ---------- */
.wcalc-sheet {
    position: fixed;
    z-index: 10000;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 75vh;
    max-height: 560px;
    background: var(--bg-card, #f6f7fc);
    border-radius: var(--radius-lg, 20px) var(--radius-lg, 20px) 0 0;
    box-shadow: 0 -8px 40px rgba(0,0,0,0.15);
    display: flex;
    flex-direction: column;
    transform: translateY(100%);
    transition: transform 0.4s cubic-bezier(0.25, 0.8, 0.25, 1);
    overflow: hidden;
    will-change: transform;
    contain: layout style paint;
}

.wcalc-sheet--open {
    transform: translateY(0);
}

.wcalc-sheet__handle {
    width: 44px;
    height: 6px;
    background: var(--border, rgba(90,82,224,0.15));
    border-radius: 3px;
    margin: 8px auto 2px;
    flex-shrink: 0;
    cursor: grab;
    transition: background 0.2s, width 0.2s;
}

.wcalc-sheet__handle:active {
    cursor: grabbing;
    background: var(--primary, #5a52e0);
    width: 48px;
}

.wcalc-sheet__handle:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 4px;
    border-radius: 2px;
}

.wcalc-sheet__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 16px 4px;
    font-weight: 600;
    color: var(--text-main, #1a1a2e);
    flex-shrink: 0;
}

.wcalc-sheet__close {
    width: 32px;
    height: 32px;
    border: none;
    border-radius: 50%;
    background: var(--bg-surface, rgba(255,255,255,0.72));
    color: var(--text-main, #1a1a2e);
    font-size: 1rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s, transform 0.15s;
}

.wcalc-sheet__close:hover {
    background: var(--bg-surface-hover, rgba(255,255,255,0.88));
    transform: scale(1.08);
}

.wcalc-sheet__close:focus-visible {
    outline: 2px solid var(--primary, #5a52e0);
    outline-offset: 2px;
}

.wcalc-sheet__close:active {
    transform: scale(0.92);
}

.wcalc-sheet__body {
    display: flex;
    flex-direction: column;
    padding: 8px 12px calc(16px + env(safe-area-inset-bottom, 0px));
    gap: 6px;
    overflow-y: auto;
    flex: 1;
    scrollbar-width: thin;
}

.wcalc-sheet__body::-webkit-scrollbar {
    width: 4px;
}

.wcalc-sheet__body::-webkit-scrollbar-thumb {
    background: var(--border, rgba(90,82,224,0.15));
    border-radius: 2px;
}

.wcalc-keypad--mobile {
    gap: 8px;
}

.wcalc-keypad--mobile .wcalc-btn {
    padding: 14px 0;
    font-size: 1.15rem;
    border-radius: var(--radius, 14px);
}

.wcalc-keypad--mobile .wcalc-btn--fn {
    font-size: 0.95rem;
}

/* ---------- Media: Mobile vs Desktop ---------- */
@media (max-width: 768px) {
    .wcalc-panel,
    .wcalc-restore {
        display: none !important;
    }
    .wcalc-fab {
        display: flex;
    }
}

@media (min-width: 769px) {
    .wcalc-fab,
    .wcalc-sheet,
    .wcalc-backdrop {
        display: none !important;
    }
}

/* ---------- Dark Theme ---------- */
[data-theme="dark"] .wcalc-panel {
    background: rgba(26,26,46,0.65);
    border-color: rgba(90,82,224,0.18);
    box-shadow: 0 12px 48px rgba(0,0,0,0.25),
                0 0 0 1px rgba(90,82,224,0.1),
                0 0 30px rgba(90,82,224,0.08);
}

[data-theme="dark"] .wcalc-panel:hover {
    box-shadow: 0 16px 56px rgba(0,0,0,0.30),
                0 0 0 1px rgba(90,82,224,0.15),
                0 0 40px rgba(90,82,224,0.12);
}

[data-theme="dark"] .wcalc-display {
    background: rgba(255,255,255,0.04);
    color: var(--text-main, #e4e4f0);
}

[data-theme="dark"] .wcalc-subdisplay {
    color: var(--text-muted, #8a8aa8);
}

[data-theme="dark"] .wcalc-history {
    background: rgba(255,255,255,0.03);
    color: var(--text-secondary, #a0a0c0);
}

[data-theme="dark"] .wcalc-btn {
    background: rgba(255,255,255,0.06);
    color: var(--text-main, #e4e4f0);
}

[data-theme="dark"] .wcalc-btn::after {
    background: rgba(140,131,255,0.15);
}

[data-theme="dark"] .wcalc-btn:hover {
    background: rgba(255,255,255,0.10);
    box-shadow: 0 2px 8px rgba(0,0,0,0.15);
}

[data-theme="dark"] .wcalc-btn--op {
    background: linear-gradient(135deg, var(--primary, #5a52e0) 0%, var(--primary-mid, #4840cc) 100%);
    box-shadow: 0 2px 12px rgba(90,82,224,0.3);
}

[data-theme="dark"] .wcalc-btn--op:hover {
    box-shadow: 0 4px 20px rgba(90,82,224,0.4);
}

[data-theme="dark"] .wcalc-btn--eq {
    background: linear-gradient(135deg, var(--accent, #00b8d4) 0%, #0097a7 100%);
    box-shadow: 0 2px 12px rgba(var(--accent-rgb), 0.25);
}

[data-theme="dark"] .wcalc-btn--eq:hover {
    box-shadow: 0 4px 20px rgba(var(--accent-rgb), 0.35);
}

[data-theme="dark"] .wcalc-btn--fn {
    background: rgba(255,255,255,0.06);
    color: var(--text-secondary, #a0a0c0);
}

[data-theme="dark"] .wcalc-btn--fn::after {
    background: rgba(140,131,255,0.1);
}

[data-theme="dark"] .wcalc-sheet {
    background: #151525;
    border-top: 1px solid rgba(90,82,224,0.15);
    box-shadow: 0 -8px 40px rgba(0,0,0,0.35),
                0 0 0 1px rgba(90,82,224,0.08);
}

[data-theme="dark"] .wcalc-sheet__header {
    color: var(--text-main, #e4e4f0);
}

[data-theme="dark"] .wcalc-sheet__close {
    background: rgba(255,255,255,0.06);
    color: var(--text-main, #e4e4f0);
}

[data-theme="dark"] .wcalc-sheet__close:hover {
    background: rgba(255,255,255,0.10);
}

[data-theme="dark"] .wcalc-fab {
    box-shadow: 0 4px 20px rgba(90,82,224,0.4),
                0 0 0 1px rgba(255,255,255,0.1);
    border-color: rgba(255,255,255,0.2);
}

[data-theme="dark"] .wcalc-fab:hover {
    box-shadow: 0 6px 28px rgba(90,82,224,0.5),
                0 0 0 2px rgba(255,255,255,0.15);
}

[data-theme="dark"] .wcalc-restore {
    box-shadow: 0 4px 24px rgba(0,0,0,0.2),
                0 0 15px rgba(90,82,224,0.2);
}

[data-theme="dark"] .wcalc-backdrop--visible {
    background: rgba(0,0,0,0.5);
}

[data-theme="dark"] .wcalc-history-toggle {
    color: var(--text-muted, #8a8aa8);
}

[data-theme="dark"] .wcalc-history-toggle:hover {
    background: rgba(255,255,255,0.03);
    color: var(--text-secondary, #a0a0c0);
}

[data-theme="dark"] .wcalc-btn:focus-visible,
[data-theme="dark"] .wcalc-fab:focus-visible,
[data-theme="dark"] .wcalc-restore:focus-visible,
[data-theme="dark"] .wcalc-sheet__close:focus-visible,
[data-theme="dark"] .wcalc-history-toggle:focus-visible,
[data-theme="dark"] .wcalc-sheet__handle:focus-visible {
    outline-color: var(--primary-light, #6c63ff);
    box-shadow: 0 0 0 4px rgba(140,131,255,0.25);
}

/* ---------- Dark theme: OS fallback (when site has no data-theme) ---------- */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme]) .wcalc-panel {
        background: rgba(26,26,46,0.65);
        border-color: rgba(90,82,224,0.18);
        box-shadow: 0 12px 48px rgba(0,0,0,0.25),
                    0 0 0 1px rgba(90,82,224,0.1),
                    0 0 30px rgba(90,82,224,0.08);
    }
    :root:not([data-theme]) .wcalc-panel:hover {
        box-shadow: 0 16px 56px rgba(0,0,0,0.30),
                    0 0 0 1px rgba(90,82,224,0.15),
                    0 0 40px rgba(90,82,224,0.12);
    }
    :root:not([data-theme]) .wcalc-display {
        background: rgba(255,255,255,0.04);
        color: var(--text-main, #e4e4f0);
    }
    :root:not([data-theme]) .wcalc-subdisplay {
        color: var(--text-muted, #8a8aa8);
    }
    :root:not([data-theme]) .wcalc-history {
        background: rgba(255,255,255,0.03);
        color: var(--text-secondary, #a0a0c0);
    }
    :root:not([data-theme]) .wcalc-btn {
        background: rgba(255,255,255,0.06);
        color: var(--text-main, #e4e4f0);
    }
    :root:not([data-theme]) .wcalc-btn::after {
        background: rgba(140,131,255,0.15);
    }
    :root:not([data-theme]) .wcalc-btn:hover {
        background: rgba(255,255,255,0.10);
        box-shadow: 0 2px 8px rgba(0,0,0,0.15);
    }
    :root:not([data-theme]) .wcalc-btn--op {
        background: linear-gradient(135deg, var(--primary, #5a52e0) 0%, var(--primary-mid, #4840cc) 100%);
        box-shadow: 0 2px 12px rgba(90,82,224,0.3);
    }
    :root:not([data-theme]) .wcalc-btn--op:hover {
        box-shadow: 0 4px 20px rgba(90,82,224,0.4);
    }
    :root:not([data-theme]) .wcalc-btn--eq {
        background: linear-gradient(135deg, var(--accent, #00b8d4) 0%, #0097a7 100%);
        box-shadow: 0 2px 12px rgba(var(--accent-rgb), 0.25);
    }
    :root:not([data-theme]) .wcalc-btn--eq:hover {
        box-shadow: 0 4px 20px rgba(var(--accent-rgb), 0.35);
    }
    :root:not([data-theme]) .wcalc-btn--fn {
        background: rgba(255,255,255,0.06);
        color: var(--text-secondary, #a0a0c0);
    }
    :root:not([data-theme]) .wcalc-btn--fn::after {
        background: rgba(140,131,255,0.1);
    }
    :root:not([data-theme]) .wcalc-sheet {
        background: #151525;
        border-top: 1px solid rgba(90,82,224,0.15);
        box-shadow: 0 -8px 40px rgba(0,0,0,0.35),
                    0 0 0 1px rgba(90,82,224,0.08);
    }
    :root:not([data-theme]) .wcalc-sheet__header {
        color: var(--text-main, #e4e4f0);
    }
    :root:not([data-theme]) .wcalc-sheet__close {
        background: rgba(255,255,255,0.06);
        color: var(--text-main, #e4e4f0);
    }
    :root:not([data-theme]) .wcalc-sheet__close:hover {
        background: rgba(255,255,255,0.10);
    }
    :root:not([data-theme]) .wcalc-fab {
        box-shadow: 0 4px 20px rgba(90,82,224,0.4),
                    0 0 0 1px rgba(255,255,255,0.1);
        border-color: rgba(255,255,255,0.2);
    }
    :root:not([data-theme]) .wcalc-fab:hover {
        box-shadow: 0 6px 28px rgba(90,82,224,0.5),
                    0 0 0 2px rgba(255,255,255,0.15);
    }
    :root:not([data-theme]) .wcalc-restore {
        box-shadow: 0 4px 24px rgba(0,0,0,0.2),
                    0 0 15px rgba(90,82,224,0.2);
    }
    :root:not([data-theme]) .wcalc-backdrop--visible {
        background: rgba(0,0,0,0.5);
    }
    :root:not([data-theme]) .wcalc-history-toggle {
        color: var(--text-muted, #8a8aa8);
    }
    :root:not([data-theme]) .wcalc-history-toggle:hover {
        background: rgba(255,255,255,0.03);
        color: var(--text-secondary, #a0a0c0);
    }
    :root:not([data-theme]) .wcalc-btn:focus-visible,
    :root:not([data-theme]) .wcalc-fab:focus-visible,
    :root:not([data-theme]) .wcalc-restore:focus-visible,
    :root:not([data-theme]) .wcalc-sheet__close:focus-visible,
    :root:not([data-theme]) .wcalc-history-toggle:focus-visible,
    :root:not([data-theme]) .wcalc-sheet__handle:focus-visible {
        outline-color: var(--primary-light, #6c63ff);
        box-shadow: 0 0 0 4px rgba(140,131,255,0.25);
    }
}

/* ---------- Accessibility: reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
    .wcalc-panel,
    .wcalc-restore,
    .wcalc-restore::before,
    .wcalc-fab,
    .wcalc-fab::before,
    .wcalc-sheet,
    .wcalc-backdrop,
    .wcalc-btn,
    .wcalc-btn::after,
    .wcalc-sheet__handle,
    .wcalc-sheet__handle::after,
    .wcalc-header__btn,
    .wcalc-sheet__close,
    .wcalc-memory-badge,
    .wcalc-body,
    .wcalc-history,
    .wcalc-display,
    .wcalc-subdisplay,
    .wcalc-history-toggle,
    .wcalc-history-clear {
        transition: none !important;
        animation: none !important;
    }
}

/* ---------- Accessibility: high contrast / forced colors ---------- */
@media (forced-colors: active) {
    .wcalc-panel,
    .wcalc-sheet,
    .wcalc-fab,
    .wcalc-restore {
        border: 2px solid CanvasText;
    }
    .wcalc-btn {
        border: 1px solid CanvasText;
    }
    .wcalc-btn--op,
    .wcalc-btn--eq {
        border: 2px solid CanvasText;
    }
    .wcalc-display {
        border: 1px solid CanvasText;
    }
}

/* ---------- Print: hide widget ---------- */
@media print {
    .wcalc-panel,
    .wcalc-restore,
    .wcalc-fab,
    .wcalc-sheet,
    .wcalc-backdrop {
        display: none !important;
    }
}