/**
 * CS AI Platform - App Layout Styles
 *
 * Styles for authenticated app pages:
 * - Minimal header with hamburger
 * - Slide-out nav shelf (left)
 * - Content area
 * - Minimal footer
 */

/* ========================================
   APP BODY STATE
   ======================================== */

body.cs-ai-app {
    background-color: var(--color-bg-alt);
    overflow-x: hidden;
}

body.nav-open {
    overflow: hidden;
}

/* ========================================
   APP HEADER
   ======================================== */

.app-header {
    position: sticky;
    top: 0;
    z-index: var(--z-sticky);
    background-color: var(--color-white);
    border-bottom: 1px solid var(--border-color-light);
    height: var(--header-height-app);
}

.app-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    padding: 0 var(--space-4);
    max-width: var(--container-max);
    margin: 0 auto;
}

/* Hamburger trigger */
.app-header__menu-trigger {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    border-radius: var(--radius-md);
    transition: background-color var(--transition-fast);
}

.app-header__menu-trigger:hover {
    background-color: var(--color-bg-alt);
}

.app-header__menu-trigger:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Hamburger icon */
.hamburger-icon {
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 24px;
    height: 24px;
}

.hamburger-icon span {
    display: block;
    height: 2px;
    background-color: var(--color-text);
    border-radius: 1px;
    transition: all var(--transition-fast);
}

.hamburger-icon span:nth-child(1) { width: 24px; }
.hamburger-icon span:nth-child(2) { width: 18px; }
.hamburger-icon span:nth-child(3) { width: 24px; }

/* Logo */
.app-header__logo {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-bold);
    color: var(--color-secondary);
    text-decoration: none;
}

.app-header__logo:hover {
    color: var(--color-primary);
}

/* User area */
.app-header__user {
    display: flex;
    align-items: center;
    gap: var(--space-3);
}

.app-header__user-name {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
}

/* ========================================
   NAV SHELF (Slide-out)
   ======================================== */

.nav-shelf {
    position: fixed;
    top: 0;
    left: 0;
    z-index: var(--z-nav-shelf);
    width: var(--nav-shelf-width);
    height: 100vh;
    background-color: var(--color-white);
    box-shadow: var(--shadow-xl);
    transform: translateX(-100%);
    transition: transform var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.nav-shelf.is-open {
    transform: translateX(0);
}

/* Shelf header */
.nav-shelf__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4) var(--space-5);
    border-bottom: 1px solid var(--border-color-light);
}

.nav-shelf__title {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.nav-shelf__close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    border-radius: var(--radius-md);
    color: var(--color-text-muted);
    transition: all var(--transition-fast);
}

.nav-shelf__close:hover {
    background-color: var(--color-bg-alt);
    color: var(--color-text);
}

/* Nav list */
.nav-shelf__list {
    flex: 1;
    list-style: none;
    margin: 0;
    padding: var(--space-4) 0;
    overflow-y: auto;
}

.nav-shelf__item {
    margin: 0;
}

.nav-shelf__link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-5);
    color: var(--color-text);
    text-decoration: none;
    font-weight: var(--font-weight-medium);
    transition: all var(--transition-fast);
}

.nav-shelf__link:hover {
    background-color: var(--color-bg-alt);
    color: var(--color-primary);
}

.nav-shelf__link.is-active {
    background-color: rgba(0, 171, 200, 0.1);
    color: var(--color-primary);
    border-left: 3px solid var(--color-primary);
    padding-left: calc(var(--space-5) - 3px);
}

/* Icon placeholder */
.nav-shelf__icon {
    width: 20px;
    height: 20px;
    background-color: var(--color-light-slate);
    border-radius: var(--radius-sm);
}

.nav-shelf__label {
    flex: 1;
}

/* Arrow for items with children */
.nav-shelf__arrow {
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    border-top: 5px solid currentColor;
    transition: transform var(--transition-fast);
}

.nav-shelf__item.is-expanded .nav-shelf__arrow {
    transform: rotate(180deg);
}

/* Submenu */
.nav-shelf__submenu {
    list-style: none;
    margin: 0;
    padding: 0;
    max-height: 0;
    overflow: hidden;
    transition: max-height var(--transition-normal);
    background-color: var(--color-bg-alt);
}

.nav-shelf__item.is-expanded .nav-shelf__submenu {
    max-height: 200px;
}

.nav-shelf__subitem {
    margin: 0;
}

.nav-shelf__sublink {
    display: block;
    padding: var(--space-2) var(--space-5) var(--space-2) var(--space-12);
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: var(--font-size-sm);
    transition: all var(--transition-fast);
}

.nav-shelf__sublink:hover {
    color: var(--color-primary);
}

/* Shelf footer */
.nav-shelf__footer {
    padding: var(--space-4) var(--space-5);
    border-top: 1px solid var(--border-color-light);
}

.nav-shelf__admin-link,
.nav-shelf__logout {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3);
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: var(--font-size-sm);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
}

.nav-shelf__admin-link:hover {
    background-color: rgba(0, 171, 200, 0.1);
    color: var(--color-primary);
}

.nav-shelf__logout:hover {
    background-color: rgba(235, 91, 80, 0.1);
    color: var(--color-danger);
}

/* ========================================
   LIBRARY SHELF (Slide-out, right side)
   ======================================== */

.library-shelf {
    position: fixed;
    top: 0;
    right: 0;
    z-index: var(--z-nav-shelf);
    width: var(--library-shelf-width);
    height: 100vh;
    background-color: var(--color-white);
    box-shadow: var(--shadow-xl);
    transform: translateX(100%);
    transition: transform var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.library-shelf.is-open {
    transform: translateX(0);
}

/* Shelf header */
.library-shelf__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-4) var(--space-5);
    border-bottom: 1px solid var(--border-color-light);
    flex-shrink: 0;
}

.library-shelf__title {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.library-shelf__close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    padding: 0;
    background: transparent;
    border: none;
    cursor: pointer;
    border-radius: var(--radius-md);
    color: var(--color-text-muted);
    transition: all var(--transition-fast);
}

.library-shelf__close:hover {
    background-color: var(--color-bg-alt);
    color: var(--color-text);
}

/* Content area — scrollable */
.library-shelf__content {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-4) var(--space-5);
}

/* Header trigger button — gold pill with label on wide screens */
.app-header__library-trigger {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    height: 40px;
    padding: 0 var(--space-3);
    background: rgba(255, 184, 0, 0.22);
    border: 1px solid rgba(255, 184, 0, 0.45);
    cursor: pointer;
    border-radius: var(--radius-full);
    color: #7a5800;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: all var(--transition-normal);
}

.app-header__library-trigger:hover {
    background: rgba(255, 184, 0, 0.35);
    border-color: rgba(255, 184, 0, 0.6);
    color: #5c4200;
    animation: library-pulse 1.5s ease-in-out infinite;
}

.app-header__library-trigger:focus {
    outline: 2px solid var(--color-accent);
    outline-offset: 2px;
}

/* Label text — hidden on small screens, visible on wide */
.app-header__library-label {
    display: none;
}

@media (min-width: 640px) {
    .app-header__library-label {
        display: inline;
    }
}

@keyframes library-pulse {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(255, 184, 0, 0.3);
    }
    50% {
        box-shadow: 0 0 0 6px rgba(255, 184, 0, 0);
    }
}

/* Library-open body state */
body.library-open {
    overflow: hidden;
}

/* ========================================
   NAV OVERLAY
   ======================================== */

.nav-overlay {
    position: fixed;
    top: 0;
    left: 0;
    z-index: calc(var(--z-nav-shelf) - 1);
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.4);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-normal), visibility var(--transition-normal);
}

.nav-overlay.is-visible {
    opacity: 1;
    visibility: visible;
}

/* ========================================
   APP MAIN CONTENT
   ======================================== */

.app-main {
    min-height: calc(100vh - var(--header-height-app) - 60px);
    padding: var(--space-6) var(--space-4);
}

.app-main > .container {
    background-color: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    padding: var(--space-6);
}

/* ========================================
   APP FOOTER
   ======================================== */

.app-footer {
    background-color: var(--color-white);
    border-top: 1px solid var(--border-color-light);
    padding: var(--space-4) 0;
}

.app-footer__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--space-4);
}

.app-footer__copyright {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
}

.app-footer__links {
    display: flex;
    gap: var(--space-6);
}

.app-footer__links a {
    font-size: var(--font-size-sm);
    color: var(--color-text-muted);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.app-footer__links a:hover {
    color: var(--color-primary);
}

/* ========================================
   RESPONSIVE
   ======================================== */

@media (max-width: 640px) {
    .app-header__user-name {
        display: none;
    }

    .app-footer__inner {
        flex-direction: column;
        gap: var(--space-3);
        text-align: center;
    }
}