/* =========================================================
   NAV10 — AI Chat
   Enterprise monochrome · No generic AI aesthetic
   ========================================================= */

.ai-body {
    margin: 0;
    background: var(--nav-white, #fff);
    color: var(--nav-black, #000);
    font-family: var(--font, Inter, system-ui, sans-serif);
}

.ai-app {
    min-height: 100vh;
    min-height: 100dvh;
    display: flex;
    flex-direction: column;
}

.ai-topbar {
    display: flex;
    align-items: center;
    gap: var(--nav-space-3, 0.75rem);
    padding: 0 var(--nav-space-5, 1.25rem);
    min-height: 60px;
    height: 60px;
    background: var(--nav-black, #000);
    color: var(--nav-white, #fff);
    position: sticky;
    top: 0;
    z-index: 40;
    border-bottom: 1px solid rgba(255, 255, 255, 0.14);
    flex-wrap: nowrap;
}

.ai-topbar__brand {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 0.75rem;
    min-width: 0;
    flex: 1;
}

.ai-topbar__brand-text {
    display: flex;
    flex-direction: column;
    gap: 2px;
    min-width: 0;
}

.ai-topbar__brand strong {
    font-size: 0.875rem;
    font-weight: 700;
    letter-spacing: 0.12em;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.ai-topbar__brand span {
    font-size: 0.625rem;
    color: rgba(255, 255, 255, 0.55);
    letter-spacing: 0.14em;
    text-transform: uppercase;
}

.site-logo--ai {
    height: 1.5rem;
    flex-shrink: 0;
}

.ai-topbar__actions {
    margin-left: auto;
    display: flex;
    flex-wrap: nowrap;
    gap: var(--nav-space-2, 0.5rem);
    flex-shrink: 0;
    align-items: center;
}

.ai-menu-toggle {
    display: none;
    width: 44px;
    height: 44px;
    border: 1px solid rgba(255, 255, 255, 0.25);
    border-radius: var(--nav-radius-xs, 4px);
    background: transparent;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 5px;
    cursor: pointer;
    flex-shrink: 0;
    position: relative;
    z-index: 5;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

.ai-menu-toggle span {
    display: block;
    width: 18px;
    height: 1.5px;
    background: var(--nav-white, #fff);
}

.ai-shell {
    flex: 1;
    display: grid;
    grid-template-columns: 272px 1fr;
    min-height: 0;
}

.ai-sidebar {
    border-right: 1px solid rgba(0, 0, 0, 0.11);
    background: rgba(0, 0, 0, 0.02);
    padding: var(--nav-space-4, 1rem);
    overflow-y: auto;
}

.ai-sidebar__head {
    display: none;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--nav-space-4, 1rem);
    font-weight: 700;
    font-size: 0.875rem;
    letter-spacing: 0.06em;
}

.ai-sidebar__close {
    border: 0;
    background: transparent;
    font-size: 1.5rem;
    cursor: pointer;
    line-height: 1;
    opacity: 0.55;
}

.ai-sidebar__label {
    margin: var(--nav-space-5, 1.25rem) 0 var(--nav-space-3, 0.65rem);
    font-size: 0.625rem;
    letter-spacing: 0.16em;
    text-transform: uppercase;
    color: rgba(0, 0, 0, 0.42);
}

.ai-sidebar__empty {
    color: rgba(0, 0, 0, 0.42);
    font-size: 0.875rem;
    margin: var(--nav-space-4, 1rem) 0;
    line-height: 1.55;
}

.ai-conversation-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.ai-conversation-item {
    display: block;
    padding: 0.75rem 0.85rem;
    border-radius: var(--nav-radius-xs, 4px);
    text-decoration: none;
    color: inherit;
    border: 1px solid transparent;
    transition: background-color 180ms ease, border-color 180ms ease;
}

.ai-conversation-item:hover,
.ai-conversation-item.is-active {
    background: var(--nav-white, #fff);
    border-color: rgba(0, 0, 0, 0.11);
}

.ai-conversation-item.is-active {
    border-color: var(--nav-black, #000);
}

.ai-conversation-item__title {
    display: block;
    font-size: 0.875rem;
    font-weight: 600;
    overflow-wrap: anywhere;
    line-height: 1.4;
}

.ai-conversation-item__date {
    display: block;
    margin-top: 0.25rem;
    font-size: 0.6875rem;
    letter-spacing: 0.06em;
    color: rgba(0, 0, 0, 0.42);
}

.ai-main {
    min-width: 0;
    display: flex;
    flex-direction: column;
    background: var(--nav-white, #fff);
}

.ai-gate {
    margin: auto;
    max-width: 440px;
    padding: var(--nav-space-8, 3rem) var(--nav-space-5, 1.5rem);
    text-align: center;
}

.ai-gate h1 {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: 800;
    letter-spacing: -0.03em;
    margin: 0 0 var(--nav-space-4, 0.85rem);
}

.ai-gate p {
    color: rgba(0, 0, 0, 0.52);
    margin: 0 0 var(--nav-space-5, 1.5rem);
    line-height: 1.65;
    font-size: 0.9375rem;
}

.ai-chat {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-height: 0;
    max-width: 820px;
    width: 100%;
    margin: 0 auto;
}

.ai-messages {
    flex: 1;
    overflow-y: auto;
    padding: var(--nav-space-6, 1.5rem) var(--nav-space-5, 1.25rem) var(--nav-space-4, 1rem);
    display: flex;
    flex-direction: column;
    gap: var(--nav-space-5, 1.25rem);
}

.ai-welcome {
    margin: auto;
    text-align: center;
    max-width: 540px;
    padding: var(--nav-space-7, 2rem) var(--nav-space-3, 0.5rem);
}

.ai-welcome h1 {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 800;
    letter-spacing: -0.04em;
    line-height: 0.95;
    margin: 0 0 var(--nav-space-4, 0.75rem);
}

.ai-welcome__lead {
    font-size: 1rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    margin: 0 0 var(--nav-space-2, 0.5rem);
}

.ai-welcome__sub {
    color: rgba(0, 0, 0, 0.52);
    margin: 0 0 var(--nav-space-6, 1.5rem);
    font-size: 0.9375rem;
    line-height: 1.65;
}

.ai-chips {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: var(--nav-space-2, 0.55rem);
}

.ai-chip {
    border: 1px solid rgba(0, 0, 0, 0.14);
    background: var(--nav-white, #fff);
    border-radius: var(--nav-radius-xs, 4px);
    padding: 0.6rem 0.95rem;
    font-size: 0.8125rem;
    cursor: pointer;
    max-width: 100%;
    overflow-wrap: anywhere;
    transition: border-color 180ms ease, background-color 180ms ease;
}

.ai-chip:hover {
    border-color: var(--nav-black, #000);
    background: rgba(0, 0, 0, 0.02);
}

.ai-msg {
    max-width: min(720px, 92%);
    overflow-wrap: anywhere;
}

.ai-msg--user {
    align-self: flex-end;
}

.ai-msg--assistant {
    align-self: flex-start;
}

.ai-msg__role {
    font-size: 0.625rem;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: rgba(0, 0, 0, 0.42);
    margin-bottom: var(--nav-space-2, 0.35rem);
}

.ai-msg--user .ai-msg__content {
    background: var(--nav-black, #000);
    color: var(--nav-white, #fff);
    padding: 0.9rem 1.1rem;
    border-radius: var(--nav-radius-md, 12px) var(--nav-radius-md, 12px) var(--nav-radius-xs, 4px) var(--nav-radius-md, 12px);
    line-height: 1.6;
    white-space: pre-wrap;
    font-size: 0.9375rem;
}

.ai-msg--assistant .ai-msg__content {
    background: rgba(0, 0, 0, 0.04);
    color: var(--nav-black, #000);
    padding: 0.9rem 1.1rem;
    border-radius: var(--nav-radius-md, 12px) var(--nav-radius-md, 12px) var(--nav-radius-md, 12px) var(--nav-radius-xs, 4px);
    line-height: 1.65;
    white-space: pre-wrap;
    border: 1px solid rgba(0, 0, 0, 0.08);
    font-size: 0.9375rem;
}

.ai-msg--loading .ai-msg__content {
    color: rgba(0, 0, 0, 0.42);
    font-style: italic;
}

.ai-msg--error .ai-msg__content {
    border-color: rgba(0, 0, 0, 0.2);
    border-style: dashed;
}

.ai-composer {
    display: flex;
    gap: var(--nav-space-3, 0.65rem);
    align-items: flex-end;
    padding: var(--nav-space-4, 0.85rem) var(--nav-space-5, 1.25rem) var(--nav-space-2, 0.35rem);
    border-top: 1px solid rgba(0, 0, 0, 0.11);
    background: var(--nav-white, #fff);
    position: sticky;
    bottom: 0;
}

.ai-composer textarea {
    flex: 1;
    resize: none;
    min-height: 52px;
    max-height: 160px;
    border: 1px solid rgba(0, 0, 0, 0.14);
    border-radius: var(--nav-radius-sm, 8px);
    padding: 0.85rem 1rem;
    font: inherit;
    line-height: 1.45;
    overflow-y: auto;
    font-size: 15px;
}

.ai-composer textarea:focus {
    outline: none;
    border-color: var(--nav-black, #000);
}

.ai-composer__hint {
    margin: 0;
    padding: 0 var(--nav-space-5, 1.25rem) var(--nav-space-4, 0.85rem);
    font-size: 0.6875rem;
    letter-spacing: 0.06em;
    color: rgba(0, 0, 0, 0.35);
}

.ai-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--nav-radius-xs, 4px);
    padding: 0.6rem 1rem;
    font-size: 0.8125rem;
    font-weight: 600;
    letter-spacing: 0.04em;
    text-decoration: none;
    border: 1px solid transparent;
    cursor: pointer;
    white-space: nowrap;
    transition: opacity 180ms ease, background-color 180ms ease;
}

.ai-btn--primary {
    background: var(--nav-black, #000);
    color: var(--nav-white, #fff);
    border-color: var(--nav-black, #000);
}

.ai-btn--primary:hover {
    opacity: 0.88;
}

.ai-btn--primary:disabled {
    opacity: 0.45;
    cursor: not-allowed;
}

.ai-btn--ghost {
    background: transparent;
    color: var(--nav-white, #fff);
    border-color: rgba(255, 255, 255, 0.3);
}

.ai-btn--ghost:hover {
    background: rgba(255, 255, 255, 0.08);
}

.ai-btn--block {
    width: 100%;
    margin-bottom: 0.25rem;
}

.ai-overlay {
    display: none;
}

.ai-overlay.is-visible {
    display: block;
}

.visually-hidden {
    position: absolute !important;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    border: 0;
}

@media (max-width: 991.98px) {
    .ai-menu-toggle {
        display: inline-flex;
    }

    .ai-shell {
        display: block;
        position: relative;
        grid-template-columns: none;
    }

    .ai-sidebar {
        position: fixed;
        inset: 0 auto 0 0;
        width: min(86vw, 320px);
        height: 100vh;
        height: 100dvh;
        z-index: 60;
        transform: translateX(-105%);
        transition: transform 280ms cubic-bezier(0.22, 1, 0.36, 1);
        background: var(--nav-white, #fff);
        border-right: 1px solid rgba(0, 0, 0, 0.11);
        overflow-y: auto;
        -webkit-overflow-scrolling: touch;
    }

    .ai-app.sidebar-open .ai-sidebar {
        transform: translateX(0);
        box-shadow: 12px 0 40px rgba(0, 0, 0, 0.28);
    }

    .ai-sidebar__head {
        display: flex;
    }

    .ai-overlay {
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.45);
        z-index: 55;
    }

    .ai-app.sidebar-open .ai-overlay,
    .ai-overlay.is-visible {
        display: block;
    }

    .ai-topbar {
        padding-inline: 0.75rem;
        gap: 0.5rem;
        height: 56px;
        min-height: 56px;
    }

    .ai-topbar__brand-text {
        display: none;
    }

    .ai-topbar__actions .ai-btn {
        padding: 0.45rem 0.65rem;
        font-size: 0.7rem;
        white-space: nowrap;
        line-height: 1.2;
    }

    .ai-topbar__actions #ai-new-chat {
        display: none;
    }

    .site-logo--ai {
        height: 1.35rem;
    }

    body.ai-body {
        overflow-x: hidden;
    }

    body.ai-body:has(.ai-app.sidebar-open) {
        overflow: hidden;
    }
}

@media (max-width: 430px) {
    .ai-composer {
        padding: var(--nav-space-3, 0.75rem) var(--nav-space-4, 0.85rem) var(--nav-space-2, 0.25rem);
    }

    .ai-composer__hint {
        padding: 0 var(--nav-space-4, 0.85rem) var(--nav-space-3, 0.75rem);
    }

    .ai-messages {
        padding: var(--nav-space-4, 1rem) var(--nav-space-4, 0.85rem);
    }

    .ai-topbar__actions .ai-btn {
        padding-inline: 0.55rem;
        font-size: 0.65rem;
    }
}