/* ============================================
   হিসাব (Hisab) - Responsive + Nav & Footer
   ============================================ */

/* --------------------------------------------
   1. HEADER / NAVIGATION
   -------------------------------------------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
    height: var(--nav-height);
    display: flex;
    align-items: center;
}

.navbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: var(--space-4);
}

/* Brand / Logo */
.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    text-decoration: none;
    font-weight: var(--font-weight-bold);
    font-size: var(--font-size-xl);
    color: var(--color-primary);
    white-space: nowrap;
}

.navbar-brand .brand-icon {
    font-size: var(--font-size-2xl);
}

.navbar-brand .brand-text {
    letter-spacing: -0.5px;
}

.navbar-brand .brand-dot {
    color: var(--color-text-muted);
    font-weight: var(--font-weight-normal);
    font-size: var(--font-size-sm);
}

/* Nav Links */
.navbar-nav {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    list-style: none;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    padding: 8px 14px;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
    text-decoration: none;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.nav-link:hover {
    color: var(--color-primary);
    background: var(--color-primary-light);
}

.nav-link.active {
    color: var(--color-primary);
    background: var(--color-primary-light);
    font-weight: var(--font-weight-semibold);
}

.nav-icon {
    font-size: var(--font-size-base);
}

/* Nav Actions */
.navbar-actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.btn-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    cursor: pointer;
    font-size: var(--font-size-base);
    transition: all var(--transition-fast);
    color: var(--color-text-secondary);
}

.btn-icon:hover {
    background: var(--color-divider);
    color: var(--color-text-primary);
    border-color: var(--color-border-hover);
}

/* Search Bar */
.search-bar {
    display: none;
    padding: var(--space-3) 0;
    border-top: 1px solid var(--color-border);
    animation: slideDown 0.2s ease forwards;
}

.search-bar.visible {
    display: block;
}

.search-form {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.search-input {
    flex: 1;
    padding: 10px 14px;
    font-size: var(--font-size-base);
    border: 2px solid var(--color-primary);
    border-radius: var(--radius-md);
    outline: none;
    background: var(--color-surface);
    color: var(--color-text-primary);
}

.search-input:focus {
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

.search-submit,
.search-close {
    padding: 10px 16px;
    border-radius: var(--radius-md);
    border: none;
    cursor: pointer;
    font-size: var(--font-size-base);
}

.search-submit {
    background: var(--color-primary);
    color: #fff;
}

.search-close {
    background: var(--color-divider);
    color: var(--color-text-secondary);
}

.search-suggestions {
    padding: var(--space-3) 0;
}

.suggestion-group {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--space-2);
}

.suggestion-label {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
}

.suggestion-tag {
    font-size: var(--font-size-xs);
    padding: 4px 10px;
    background: var(--color-divider);
    border-radius: var(--radius-full);
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.suggestion-tag:hover {
    background: var(--color-primary-light);
    color: var(--color-primary);
}

/* Theme Toggle Icons */
[data-theme="light"] .theme-icon-dark { display: none; }
[data-theme="dark"] .theme-icon-light { display: none; }

/* Menu Toggle */
.menu-toggle .menu-icon-close { display: none; }
.menu-toggle.open .menu-icon-open { display: none; }
.menu-toggle.open .menu-icon-close { display: inline; }

/* --------------------------------------------
   2. MOBILE MENU
   -------------------------------------------- */
.mobile-menu-overlay {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: var(--z-overlay);
}

.mobile-menu-overlay.visible {
    display: block;
}

.mobile-menu {
    position: fixed;
    top: 0;
    right: -100%;
    width: 300px;
    max-width: 85vw;
    height: 100vh;
    background: var(--color-surface);
    z-index: var(--z-modal);
    transition: right var(--transition-normal);
    overflow-y: auto;
    box-shadow: var(--shadow-xl);
}

.mobile-menu.visible {
    right: 0;
}

.mobile-menu-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4) var(--space-5);
    border-bottom: 1px solid var(--color-border);
    position: sticky;
    top: 0;
    background: var(--color-surface);
    z-index: 1;
}

.mobile-menu-title {
    font-weight: var(--font-weight-semibold);
    font-size: var(--font-size-base);
}

.mobile-menu-nav {
    list-style: none;
    padding: var(--space-3) 0;
}

.mobile-nav-link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 12px var(--space-5);
    font-size: var(--font-size-base);
    color: var(--color-text-primary);
    text-decoration: none;
    transition: background var(--transition-fast);
}

.mobile-nav-link:hover,
.mobile-nav-link.active {
    background: var(--color-primary-light);
    color: var(--color-primary);
}

.mobile-nav-sub {
    padding-left: var(--space-12);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
}

.mobile-nav-divider {
    height: 1px;
    background: var(--color-border);
    margin: var(--space-2) var(--space-5);
    border: none;
}

/* --------------------------------------------
   3. FOOTER
   -------------------------------------------- */
.site-footer {
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    padding-top: var(--space-12);
    padding-bottom: var(--space-6);
    margin-top: var(--space-12);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-8);
}

@media (min-width: 768px) {
    .footer-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.footer-heading {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-3);
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.footer-links a {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    text-decoration: none;
    transition: color var(--transition-fast);
    display: inline-block;
    padding: 2px 0;
}

.footer-links a:hover {
    color: var(--color-primary);
}

/* Social Share */
.footer-social {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.footer-social-label {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
}

.social-buttons {
    display: flex;
    gap: var(--space-2);
}

.social-btn {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    border: 1px solid var(--color-border);
    background: var(--color-surface);
    cursor: pointer;
    font-size: var(--font-size-base);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
}

.social-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* Footer Bottom */
.footer-bottom {
    margin-top: var(--space-8);
    padding-top: var(--space-6);
}

.footer-disclaimer {
    margin-bottom: var(--space-6);
}

.disclaimer-text {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
    line-height: var(--line-height-relaxed);
}

.footer-divider {
    border: 0;
    border-top: 1px solid var(--color-border);
    margin: var(--space-4) 0;
}

.copyright-text {
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
}

.copyright-subtext {
    font-size: var(--font-size-xs);
    color: var(--color-text-muted);
}

/* Footer Ad */
.footer-ad-slot {
    text-align: center;
}

.ad-label {
    font-size: 10px;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--space-2);
}

.ad-container {
    min-height: 90px;
    background: var(--color-divider);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
}

/* --------------------------------------------
   4. BACK TO TOP BUTTON
   -------------------------------------------- */
.back-to-top {
    position: fixed;
    bottom: 24px;
    right: 24px;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-full);
    background: var(--color-primary);
    color: #ffffff;
    border: none;
    cursor: pointer;
    font-size: var(--font-size-lg);
    box-shadow: var(--shadow-lg);
    z-index: var(--z-sticky);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transform: translateY(100px);
    transition: all var(--transition-normal);
    pointer-events: none;
}

.back-to-top.visible {
    opacity: 1;
    transform: translateY(0);
    pointer-events: all;
}

.back-to-top:hover {
    background: var(--color-primary-hover);
    transform: translateY(-3px) scale(1.05);
}

/* --------------------------------------------
   5. BREADCRUMB
   -------------------------------------------- */
.breadcrumb-wrapper {
    padding: var(--space-3) 0;
    margin-top: var(--nav-height);
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-border);
}

.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    list-style: none;
    gap: var(--space-1);
    align-items: center;
    font-size: var(--font-size-sm);
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    color: var(--color-text-muted);
}

.breadcrumb-item + .breadcrumb-item::before {
    content: '›';
    font-size: var(--font-size-lg);
    color: var(--color-border-hover);
    margin-right: var(--space-1);
}

.breadcrumb-item a {
    color: var(--color-primary);
    text-decoration: none;
}

.breadcrumb-item a:hover {
    text-decoration: underline;
}

.breadcrumb-item.active {
    color: var(--color-text-primary);
    font-weight: var(--font-weight-medium);
}

/* --------------------------------------------
   6. RESPONSIVE BREAKPOINTS
   -------------------------------------------- */
@media (max-width: 767px) {
    .navbar-nav { display: none; }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-6);
    }
    
    .navbar-brand .brand-dot {
        display: none;
    }
    
    .navbar-brand {
        font-size: var(--font-size-lg);
    }
}

@media (min-width: 768px) {
    .navbar-nav {
        display: flex;
    }
    
    .menu-toggle {
        display: none;
    }
}

@media (max-width: 1023px) {
    .calculator-layout {
        grid-template-columns: 1fr !important;
    }
}

/* --------------------------------------------
   7. DARK MODE
   -------------------------------------------- */
[data-theme="dark"] .site-header,
[data-theme="dark"] .site-footer,
[data-theme="dark"] .mobile-menu {
    background: var(--color-surface);
}

[data-theme="dark"] .btn-icon {
    background: var(--color-surface);
}

[data-theme="dark"] .search-input {
    background: var(--color-surface);
}

[data-theme="dark"] .mobile-menu-overlay {
    background: rgba(0, 0, 0, 0.7);
}

/* --------------------------------------------
   RESPONSIVE CSS LOADED
   -------------------------------------------- */