/* 
 * SimpleFeasibility v2 - Layout Styles
 * App Shell, Sidebar, Header, and Page Layouts
 */

/* ═══════════════════════════════════════════════════════════════
   APP SHELL
   ═══════════════════════════════════════════════════════════════ */

.app-shell {
    min-height: 100vh;
    background-color: var(--bg-secondary);
}

.main-app {
    display: flex;
    min-height: 100vh;
}

/* ═══════════════════════════════════════════════════════════════
   LOADING SCREEN
   ═══════════════════════════════════════════════════════════════ */

.loading-screen {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    z-index: var(--z-maximum);
    transition: opacity var(--duration-500) var(--ease-out);
}

.loading-screen.fade-out {
    opacity: 0;
    pointer-events: none;
}

.loading-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    animation: fadeIn var(--duration-500) var(--ease-out);
}

.loading-logo {
    width: 64px;
    height: 64px;
    margin-bottom: var(--space-6);
    animation: pulse 2s infinite;
}

.loading-logo svg {
    width: 100%;
    height: 100%;
}

.loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--border-primary);
    border-top-color: var(--color-primary-500);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: var(--space-4);
}

.loading-text {
    font-size: var(--text-sm);
    color: var(--text-tertiary);
    font-weight: var(--font-medium);
}

/* ═══════════════════════════════════════════════════════════════
   SIDEBAR
   ═══════════════════════════════════════════════════════════════ */

.sidebar {
    width: var(--sidebar-width);
    height: 100vh;
    position: fixed;
    left: 0;
    top: 0;
    display: flex;
    flex-direction: column;
    background-color: var(--surface-primary);
    border-right: var(--border-width-1) solid var(--border-primary);
    z-index: var(--z-fixed);
    transition: width var(--duration-300) var(--ease-premium),
                transform var(--duration-300) var(--ease-premium);
}

.sidebar.collapsed {
    width: var(--sidebar-width-collapsed);
}

.sidebar.collapsed .logo-text,
.sidebar.collapsed .nav-section-title,
.sidebar.collapsed .nav-item span,
.sidebar.collapsed .nav-badge,
.sidebar.collapsed .user-info {
    opacity: 0;
    visibility: hidden;
}

.sidebar.collapsed .sidebar-toggle svg {
    transform: rotate(180deg);
}

/* Sidebar Header */
.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-5);
    border-bottom: var(--border-width-1) solid var(--border-primary);
}

.logo {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.logo-icon {
    width: 36px;
    height: 36px;
    flex-shrink: 0;
}

.logo-text {
    font-size: var(--text-lg);
    font-weight: var(--font-bold);
    color: var(--text-primary);
    white-space: nowrap;
    transition: opacity var(--duration-200) var(--ease-out);
}

.sidebar-toggle {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    color: var(--text-tertiary);
    transition: all var(--duration-150) var(--ease-out);
}

.sidebar-toggle:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.sidebar-toggle svg {
    width: 18px;
    height: 18px;
    transition: transform var(--duration-300) var(--ease-out);
}

/* Sidebar Navigation */
.sidebar-nav {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-4);
}

.nav-section {
    margin-bottom: var(--space-6);
}

.nav-section-title {
    font-size: var(--text-xs);
    font-weight: var(--font-semibold);
    color: var(--text-muted);
    letter-spacing: var(--tracking-wider);
    padding: var(--space-2) var(--space-3);
    margin-bottom: var(--space-1);
    transition: opacity var(--duration-200) var(--ease-out);
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3);
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    font-weight: var(--font-medium);
    font-size: var(--text-sm);
    transition: all var(--duration-150) var(--ease-out);
    margin-bottom: var(--space-1);
    position: relative;
}

.nav-item svg {
    width: 20px;
    height: 20px;
    flex-shrink: 0;
    transition: stroke var(--duration-150) var(--ease-out);
}

.nav-item span {
    white-space: nowrap;
    transition: opacity var(--duration-200) var(--ease-out);
}

.nav-item:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.nav-item.active {
    background-color: var(--surface-selected);
    color: var(--color-accent-600);
}

[data-theme="dark"] .nav-item.active {
    color: var(--color-accent-400);
}

.nav-item.active::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 24px;
    background: var(--gradient-brand);
    border-radius: var(--radius-full);
}

.nav-badge {
    font-size: var(--text-xs);
    font-weight: var(--font-bold);
    padding: var(--space-0-5) var(--space-2);
    background: var(--gradient-brand);
    color: white;
    border-radius: var(--radius-full);
    margin-left: auto;
    transition: opacity var(--duration-200) var(--ease-out);
}

/* Sidebar Footer */
.sidebar-footer {
    padding: var(--space-4);
    border-top: var(--border-width-1) solid var(--border-primary);
    position: relative;
}

.user-profile {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-2);
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: background-color var(--duration-150) var(--ease-out);
}

.user-profile:hover {
    background-color: var(--surface-hover);
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    object-fit: cover;
    background-color: var(--surface-secondary);
    flex-shrink: 0;
}

.user-info {
    flex: 1;
    min-width: 0;
    transition: opacity var(--duration-200) var(--ease-out);
}

.user-name {
    display: block;
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.user-plan {
    display: block;
    font-size: var(--text-xs);
    color: var(--text-tertiary);
}

.user-menu-btn {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-md);
    color: var(--text-tertiary);
    transition: all var(--duration-150) var(--ease-out);
}

.user-menu-btn:hover {
    background-color: var(--surface-active);
    color: var(--text-primary);
}

.user-menu-btn svg {
    width: 18px;
    height: 18px;
}

/* User Dropdown */
.user-dropdown {
    position: absolute;
    bottom: calc(100% + 8px);
    left: var(--space-4);
    right: var(--space-4);
    background-color: var(--surface-primary);
    border: var(--border-width-1) solid var(--border-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: var(--space-2);
    z-index: var(--z-dropdown);
    animation: slideUp var(--duration-200) var(--ease-out);
}

.user-dropdown.hidden {
    display: none;
}

/* Dropdown Header */
.dropdown-header {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3);
    margin-bottom: var(--space-1);
}

.dropdown-avatar {
    width: 48px;
    height: 48px;
    border-radius: var(--radius-full);
    object-fit: cover;
    border: 2px solid var(--border-primary);
}

.dropdown-user-info {
    flex: 1;
    min-width: 0;
}

.dropdown-name {
    display: block;
    font-size: var(--text-sm);
    font-weight: var(--font-semibold);
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.dropdown-email {
    display: block;
    font-size: var(--text-xs);
    color: var(--text-tertiary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

/* User Email */
.user-email {
    display: none;
}

/* User Plan Premium */
.user-plan-premium {
    color: var(--color-accent-500) !important;
    font-weight: var(--font-semibold);
}

.logout-btn {
    color: var(--color-error-500) !important;
}

.logout-btn:hover {
    background-color: var(--color-error-50) !important;
}

[data-theme="dark"] .logout-btn:hover {
    background-color: rgba(244, 63, 94, 0.1) !important;
}

/* Login Button (for guests) */
.login-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-3);
    width: 100%;
    padding: var(--space-3) var(--space-4);
    background: var(--surface-primary);
    border: var(--border-width-1) solid var(--border-primary);
    border-radius: var(--radius-lg);
    color: var(--text-primary);
    font-size: var(--text-sm);
    font-weight: var(--font-medium);
    cursor: pointer;
    transition: all var(--duration-200) var(--ease-out);
}

.login-btn:hover {
    background: var(--surface-hover);
    border-color: var(--border-secondary);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.login-btn .google-icon {
    flex-shrink: 0;
}

/* Hidden utility */
.hidden {
    display: none !important;
}

/* ═══════════════════════════════════════════════════════════════
   MAIN CONTENT
   ═══════════════════════════════════════════════════════════════ */

.main-content {
    flex: 1;
    margin-left: var(--sidebar-width);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: margin-left var(--duration-300) var(--ease-premium);
}

.sidebar.collapsed ~ .main-content {
    margin-left: var(--sidebar-width-collapsed);
}

/* Content Header */
.content-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-height);
    padding: 0 var(--space-6);
    background-color: var(--surface-primary);
    border-bottom: var(--border-width-1) solid var(--border-primary);
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

.mobile-menu-btn {
    display: none;
    width: 40px;
    height: 40px;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    transition: all var(--duration-150) var(--ease-out);
}

.mobile-menu-btn:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.mobile-menu-btn svg {
    width: 24px;
    height: 24px;
}

.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-size: var(--text-sm);
    color: var(--text-tertiary);
}

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

.header-right {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

/* Search */
.search-container {
    position: relative;
    width: 320px;
}

.search-icon {
    position: absolute;
    left: var(--space-3);
    top: 50%;
    transform: translateY(-50%);
    width: 18px;
    height: 18px;
    color: var(--text-muted);
    pointer-events: none;
}

.search-input {
    width: 100%;
    padding: var(--space-2-5) var(--space-10);
    padding-right: var(--space-12);
    background-color: var(--surface-secondary);
    border: var(--border-width-1) solid transparent;
    border-radius: var(--radius-lg);
    font-size: var(--text-sm);
    transition: all var(--duration-150) var(--ease-out);
}

.search-input:focus {
    background-color: var(--surface-primary);
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.search-shortcut {
    position: absolute;
    right: var(--space-3);
    top: 50%;
    transform: translateY(-50%);
    font-size: var(--text-xs);
    font-family: var(--font-sans);
    padding: var(--space-1) var(--space-2);
    background-color: var(--surface-primary);
    border: var(--border-width-1) solid var(--border-primary);
    border-radius: var(--radius-md);
    color: var(--text-muted);
}

/* Header Buttons */
.header-btn {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-lg);
    color: var(--text-secondary);
    position: relative;
    transition: all var(--duration-150) var(--ease-out);
}

.header-btn:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.header-btn svg {
    width: 20px;
    height: 20px;
}

.notification-badge {
    position: absolute;
    top: 6px;
    right: 6px;
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 10px;
    font-weight: var(--font-bold);
    background: var(--gradient-brand);
    color: white;
    border-radius: var(--radius-full);
}

/* Theme Toggle */
.theme-toggle .moon-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .sun-icon {
    display: none;
}

[data-theme="dark"] .theme-toggle .moon-icon {
    display: block;
}

/* ═══════════════════════════════════════════════════════════════
   PAGE CONTAINER
   ═══════════════════════════════════════════════════════════════ */

.page-container {
    flex: 1;
    padding: var(--space-6);
    max-width: var(--content-max-width);
    margin: 0 auto;
    width: 100%;
}

.page {
    display: none;
    animation: fadeIn var(--duration-300) var(--ease-out);
}

.page.active {
    display: block;
}

/* Page Header */
.page-header {
    margin-bottom: var(--space-8);
}

.page-title {
    font-size: var(--text-3xl);
    font-weight: var(--font-bold);
    color: var(--text-primary);
    margin-bottom: var(--space-2);
}

.page-subtitle {
    font-size: var(--text-base);
    color: var(--text-tertiary);
}

/* ═══════════════════════════════════════════════════════════════
   GRID LAYOUTS
   ═══════════════════════════════════════════════════════════════ */

.grid {
    display: grid;
    gap: var(--space-6);
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

.grid-4 {
    grid-template-columns: repeat(4, 1fr);
}

.grid-auto {
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
}

/* ═══════════════════════════════════════════════════════════════
   TOAST CONTAINER
   ═══════════════════════════════════════════════════════════════ */

.toast-container {
    position: fixed;
    bottom: var(--space-6);
    right: var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    z-index: var(--z-toast);
    pointer-events: none;
}

.toast {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-4);
    background-color: var(--surface-primary);
    border: var(--border-width-1) solid var(--border-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    min-width: 320px;
    max-width: 480px;
    pointer-events: auto;
    animation: slideInRight var(--duration-300) var(--ease-out);
}

.toast-icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.toast-content {
    flex: 1;
}

.toast-title {
    font-weight: var(--font-semibold);
    color: var(--text-primary);
    margin-bottom: var(--space-0-5);
}

.toast-message {
    font-size: var(--text-sm);
    color: var(--text-secondary);
}

.toast-close {
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-muted);
    border-radius: var(--radius-md);
    transition: all var(--duration-150) var(--ease-out);
}

.toast-close:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.toast-success .toast-icon { color: var(--color-success-500); }
.toast-error .toast-icon { color: var(--color-error-500); }
.toast-warning .toast-icon { color: var(--color-warning-500); }
.toast-info .toast-icon { color: var(--color-primary-500); }

/* ═══════════════════════════════════════════════════════════════
   MODAL
   ═══════════════════════════════════════════════════════════════ */

.modal-container {
    position: fixed;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: var(--bg-overlay);
    z-index: var(--z-modal);
    padding: var(--space-6);
    animation: fadeIn var(--duration-200) var(--ease-out);
}

.modal-container.hidden {
    display: none;
}

.modal {
    background-color: var(--surface-primary);
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-2xl);
    max-width: 560px;
    width: 100%;
    max-height: 90vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    animation: scaleIn var(--duration-300) var(--ease-out);
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-5) var(--space-6);
    border-bottom: var(--border-width-1) solid var(--border-primary);
}

.modal-title {
    font-size: var(--text-xl);
    font-weight: var(--font-semibold);
    color: var(--text-primary);
}

.modal-close {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-lg);
    color: var(--text-tertiary);
    transition: all var(--duration-150) var(--ease-out);
}

.modal-close:hover {
    background-color: var(--surface-hover);
    color: var(--text-primary);
}

.modal-close svg {
    width: 20px;
    height: 20px;
}

.modal-body {
    padding: var(--space-6);
    overflow-y: auto;
    flex: 1;
}

.modal-footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: var(--space-3);
    padding: var(--space-4) var(--space-6);
    border-top: var(--border-width-1) solid var(--border-primary);
    background-color: var(--surface-secondary);
}

/* ═══════════════════════════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════════════════════════ */

@media (max-width: 1024px) {
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .search-container {
        width: 240px;
    }
}

@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
    }
    
    .sidebar.open {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .mobile-menu-btn {
        display: flex;
    }
    
    .search-container {
        display: none;
    }
    
    .grid-2, .grid-3, .grid-4 {
        grid-template-columns: 1fr;
    }
    
    .page-container {
        padding: var(--space-4);
    }
    
    .content-header {
        padding: 0 var(--space-4);
    }
}

@media (max-width: 480px) {
    .toast-container {
        left: var(--space-4);
        right: var(--space-4);
        bottom: var(--space-4);
    }
    
    .toast {
        min-width: 100%;
    }
    
    .header-btn:not(.mobile-menu-btn) {
        display: none;
    }
}