:root {
    --mc-bg: #f2f4f7;
    --mc-panel: #ffffff;
    --mc-accent: #1b6ec2;
    --mc-accent-dark: #144f8a;
    --mc-border: #dfe3e8;
    --mc-text: #1f2933;
    --mc-muted: #6b7280;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    color: var(--mc-text);
    background: var(--mc-bg);
}

/* ---------- login ---------- */
.login-shell {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #1b6ec2 0%, #144f8a 100%);
}
.login-card {
    background: var(--mc-panel);
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0,0,0,.25);
    width: 100%;
    max-width: 380px;
    display: flex;
    flex-direction: column;
    gap: .75rem;
}
.login-card h1 { margin: 0 0 .25rem; font-size: 1.6rem; color: var(--mc-accent-dark); }
.login-card p { margin: 0 0 1rem; color: var(--mc-muted); font-size: .9rem; }
.login-card input {
    padding: .65rem .8rem;
    border: 1px solid var(--mc-border);
    border-radius: 8px;
    font-size: 1rem;
}
.login-card button {
    margin-top: .5rem;
    padding: .7rem;
    border: none;
    border-radius: 8px;
    background: var(--mc-accent);
    color: #fff;
    font-size: 1rem;
    cursor: pointer;
}
.login-card button:disabled { opacity: .6; cursor: default; }
.login-secondary {
    background: #fff !important;
    color: var(--mc-accent-dark) !important;
    border: 1px solid var(--mc-accent) !important;
}
.login-secondary:hover { background: #f4f8fc !important; }
.login-divider {
    display: flex;
    align-items: center;
    gap: .6rem;
    color: var(--mc-muted);
    font-size: .78rem;
    margin: .35rem 0;
}
.login-divider::before, .login-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: var(--mc-border);
}
.login-google {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: .6rem;
    padding: .65rem;
    border: 1px solid var(--mc-border) !important;
    border-radius: 8px;
    background: #fff !important;
    color: var(--mc-text) !important;
    font-size: .95rem;
    cursor: pointer;
}
.login-google:hover { background: #f7f9fb !important; }
.login-error {
    background: #fdecea;
    color: #b3261e;
    border-radius: 8px;
    padding: .6rem .8rem;
    font-size: .85rem;
}

/* ---------- chat layout ---------- */
.chat-loading { padding: 3rem; text-align: center; color: var(--mc-muted); }

.chat-shell {
    display: flex;
    height: 100vh;
    overflow: hidden;
}

.chat-sidebar {
    width: 300px;
    min-width: 240px;
    background: var(--mc-panel);
    border-right: 1px solid var(--mc-border);
    display: flex;
    flex-direction: column;
}
.chat-sidebar-header {
    padding: 1rem;
    border-bottom: 1px solid var(--mc-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: .5rem;
}
.chat-sidebar-header .brand { font-weight: 700; color: var(--mc-accent-dark); font-size: 1.1rem; }
.chat-sidebar-header .me { font-size: .8rem; color: var(--mc-muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.chat-logout {
    border: 1px solid var(--mc-border);
    background: transparent;
    border-radius: 6px;
    padding: .25rem .55rem;
    cursor: pointer;
    font-size: .8rem;
    color: var(--mc-muted);
}
.chat-section-title {
    padding: .75rem 1rem .25rem;
    font-size: .72rem;
    letter-spacing: .08em;
    text-transform: uppercase;
    color: var(--mc-muted);
}
.chat-convs, .chat-users { overflow-y: auto; }
.chat-convs { flex: 0 1 auto; max-height: 45%; }
.chat-users { flex: 1 1 auto; border-top: 1px solid var(--mc-border); }

.chat-item {
    padding: .6rem 1rem;
    cursor: pointer;
    display: flex;
    flex-direction: column;
    gap: .15rem;
    border-left: 3px solid transparent;
}
.chat-item:hover { background: #f4f8fc; }
.chat-item.active { background: #e8f1fa; border-left-color: var(--mc-accent); }
.chat-item-row { display: flex; align-items: center; justify-content: space-between; gap: .5rem; }
.chat-item-title { font-weight: 600; font-size: .92rem; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.chat-item-preview { font-size: .78rem; color: var(--mc-muted); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.chat-badge {
    background: var(--mc-accent);
    color: #fff;
    font-size: .7rem;
    border-radius: 999px;
    padding: .05rem .45rem;
    font-weight: 700;
}

/* ---------- main pane ---------- */
.chat-main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.chat-main-header {
    padding: .9rem 1.25rem;
    background: var(--mc-panel);
    border-bottom: 1px solid var(--mc-border);
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: .6rem;
}
.chat-main-title { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* Sidebar toggle — hidden on desktop, shown on mobile via the media query below. */
.chat-menu-btn,
.chat-close-btn { display: none; }
.chat-menu-btn {
    border: none;
    background: transparent;
    font-size: 1.35rem;
    line-height: 1;
    cursor: pointer;
    color: var(--mc-accent-dark);
    padding: 0 .2rem;
}
.chat-sidebar-header { gap: .5rem; }
.chat-sidebar-id { min-width: 0; }
.chat-sidebar-actions { display: flex; align-items: center; gap: .5rem; flex-shrink: 0; }
.chat-close-btn {
    border: none;
    background: transparent;
    cursor: pointer;
    font-size: 1.1rem;
    line-height: 1;
    color: var(--mc-muted);
    padding: 0 .2rem;
}
.chat-backdrop { display: none; }
.chat-empty {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--mc-muted);
}
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 1.25rem;
    display: flex;
    flex-direction: column;
    gap: .5rem;
}
.chat-load-more {
    align-self: center;
    border: 1px solid var(--mc-border);
    background: var(--mc-panel);
    border-radius: 999px;
    padding: .3rem .9rem;
    font-size: .8rem;
    cursor: pointer;
    color: var(--mc-muted);
}
.chat-msg {
    max-width: 70%;
    align-self: flex-start;
    background: var(--mc-panel);
    border: 1px solid var(--mc-border);
    border-radius: 12px 12px 12px 4px;
    padding: .5rem .75rem;
    position: relative;
}
/* Tap target to open the delete menu — reliable on every device incl. iPhone,
   where long-press is intercepted by the OS. Shown only on your own messages. */
.chat-msg-menu-btn {
    position: absolute;
    top: 1px;
    right: 4px;
    border: none;
    background: transparent;
    color: var(--mc-muted);
    font-size: 1.05rem;
    line-height: 1;
    cursor: pointer;
    padding: 2px 5px;
    border-radius: 5px;
    opacity: .5;
}
.chat-msg-menu-btn:hover { opacity: 1; background: rgba(0, 0, 0, .07); }
.chat-msg.mine { padding-right: 1.6rem; }
@media (max-width: 768px) {
    .chat-msg-menu-btn { opacity: .8; font-size: 1.2rem; padding: 3px 7px; } /* easier tap target */
}
.chat-msg.mine {
    align-self: flex-end;
    background: #dcebfa;
    border-color: #c4ddf5;
    border-radius: 12px 12px 4px 12px;
}
.chat-msg-meta { font-size: .72rem; color: var(--mc-muted); margin-bottom: .15rem; }
.chat-msg-text { font-size: .93rem; white-space: pre-wrap; word-break: break-word; }
.chat-img { max-width: 320px; max-height: 260px; border-radius: 8px; display: block; margin-top: .35rem; }
.chat-video { max-width: 320px; max-height: 280px; border-radius: 8px; display: block; margin-top: .35rem; background: #000; }

/* clickable thumbnail (image/video) that opens the original in a lightbox */
.chat-thumb { position: relative; display: inline-block; cursor: pointer; margin-top: .35rem; line-height: 0; }
.chat-thumb .chat-img { margin-top: 0; }
.chat-thumb-video .chat-img { background: #000; }
.chat-play {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: rgba(0, 0, 0, .55);
    color: #fff;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    padding-left: 4px;
    pointer-events: none;
}

/* fullscreen lightbox showing the original image/video */
.chat-lightbox {
    position: fixed;
    inset: 0;
    z-index: 60;
    background: rgba(0, 0, 0, .85);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}
.chat-lightbox-media {
    max-width: 96vw;
    max-height: 92vh;
    border-radius: 6px;
    box-shadow: 0 10px 50px rgba(0, 0, 0, .6);
}
.chat-lightbox-close {
    position: fixed;
    top: 1rem;
    right: 1.1rem;
    width: 40px;
    height: 40px;
    border: none;
    border-radius: 50%;
    background: rgba(255, 255, 255, .15);
    color: #fff;
    font-size: 1.1rem;
    cursor: pointer;
}
.chat-lightbox-close:hover { background: rgba(255, 255, 255, .3); }
.chat-file {
    display: inline-flex;
    align-items: center;
    gap: .35rem;
    margin-top: .35rem;
    font-size: .85rem;
    color: var(--mc-accent-dark);
    text-decoration: none;
    background: #eef4fb;
    border-radius: 8px;
    padding: .35rem .6rem;
}
.chat-typing { padding: 0 1.25rem .25rem; font-size: .78rem; color: var(--mc-muted); font-style: italic; }
.chat-att-wrap { display: inline-block; }

/* Long-press → delete menu on touch: suppress the native selection/callout on own
   messages and on media, so the long-press opens our menu instead of the OS popup. */
.chat-msg.mine {
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
}
.chat-thumb, .chat-img, .chat-video { -webkit-touch-callout: none; }

/* right-click delete menu */
.chat-ctx-backdrop { position: fixed; inset: 0; z-index: 50; }
.chat-ctx-menu {
    position: fixed;
    z-index: 51;
    background: var(--mc-panel);
    border: 1px solid var(--mc-border);
    border-radius: 8px;
    box-shadow: 0 6px 24px rgba(0, 0, 0, .2);
    padding: .25rem;
    min-width: 180px;
    max-width: calc(100vw - 16px);
}
.chat-ctx-menu button {
    display: block;
    width: 100%;
    text-align: left;
    border: none;
    background: transparent;
    padding: .5rem .7rem;
    font-size: .9rem;
    cursor: pointer;
    border-radius: 6px;
    color: #b3261e;
}
.chat-ctx-menu button:hover { background: #fdecea; }

/* ---------- composer ---------- */
.chat-compose {
    display: flex;
    flex-direction: column;
    gap: .5rem;
    padding: .75rem 1.25rem;
    background: var(--mc-panel);
    border-top: 1px solid var(--mc-border);
}
.chat-compose-row {
    display: flex;
    gap: .5rem;
    align-items: flex-end;
}
.chat-compose textarea {
    flex: 1;
    resize: none;
    height: 60px;
    padding: .55rem .75rem;
    border: 1px solid var(--mc-border);
    border-radius: 10px;
    font-family: inherit;
    font-size: .95rem;
}
.chat-send {
    border: none;
    background: var(--mc-accent);
    color: #fff;
    border-radius: 10px;
    padding: .6rem 1.2rem;
    font-size: .95rem;
    cursor: pointer;
    height: 44px;
}
.chat-send:disabled { opacity: .6; cursor: default; }
.chat-attach { display: flex; gap: .5rem; align-items: center; flex-wrap: wrap; }
.chat-attach-btn {
    display: inline-flex;
    align-items: center;
    gap: .3rem;
    font-size: .82rem;
    color: var(--mc-accent-dark);
    background: #eef4fb;
    border: 1px solid #c4ddf5;
    border-radius: 999px;
    padding: .3rem .75rem;
    cursor: pointer;
    user-select: none;
}
.chat-attach-btn:hover { background: #e2eefb; }
.chat-attach-btn input[type=file] {
    /* the label is the visible control; keep the real input reachable but hidden */
    position: absolute;
    width: 1px;
    height: 1px;
    opacity: 0;
    overflow: hidden;
    clip: rect(0 0 0 0);
}
/* Camera/video capture is only meaningful on touch devices — shown via the mobile media query. */
.chat-attach-capture { display: none; }
.chat-pending {
    padding: .35rem 1.25rem;
    background: var(--mc-panel);
    display: flex;
    flex-wrap: wrap;
    gap: .4rem;
    font-size: .8rem;
}
.chat-pending-chip {
    background: #eef4fb;
    border: 1px solid #c4ddf5;
    border-radius: 999px;
    padding: .15rem .6rem;
    display: inline-flex;
    align-items: center;
    gap: .35rem;
}
.chat-pending-chip button { border: none; background: transparent; cursor: pointer; color: var(--mc-muted); }
.chat-error {
    margin: 0 1.25rem .5rem;
    background: #fdecea;
    color: #b3261e;
    border-radius: 8px;
    padding: .45rem .7rem;
    font-size: .82rem;
}

/* ---------- mobile: off-canvas sidebar with show/hide ---------- */
@media (max-width: 768px) {
    .chat-menu-btn { display: inline-flex; align-items: center; }
    .chat-close-btn { display: inline-flex; align-items: center; }

    /* The conversations/users panel slides in from the left as an overlay. */
    .chat-sidebar {
        position: fixed;
        top: 0;
        left: 0;
        height: 100vh;
        width: min(86vw, 330px);
        z-index: 40;
        transform: translateX(-100%);
        transition: transform .25s ease;
        box-shadow: 0 0 40px rgba(0, 0, 0, .35);
    }
    .chat-shell.sidebar-open .chat-sidebar { transform: translateX(0); }

    .chat-convs { max-height: 50%; }

    /* Dimmed backdrop behind the open panel; tap to close. */
    .chat-shell.sidebar-open .chat-backdrop {
        display: block;
        position: fixed;
        inset: 0;
        z-index: 30;
        background: rgba(0, 0, 0, .45);
    }

    .chat-msg { max-width: 85%; }
    .chat-img { max-width: 78vw; }
    .chat-compose { padding: .6rem .75rem; }
    .chat-messages { padding: .75rem .85rem; }

    /* Camera + video capture buttons appear on mobile. */
    .chat-attach-capture { display: inline-flex; }
}