/* ============================================================
   AITS NEXUS — Cyberpunk Terminal Aesthetic v2
   Clean, spacious layout with premium messaging feel.
   ============================================================ */

:root {
    /* --- Core palette --- */
    --bg-void:        #06080d;
    --bg-primary:     #0a0e18;
    --bg-secondary:   #0f1420;
    --bg-tertiary:    #151b2b;
    --bg-elevated:    #1a2236;

    /* --- Glass --- */
    --glass:          rgba(12, 18, 32, 0.72);
    --glass-heavy:    rgba(8, 12, 22, 0.88);
    --glass-border:   rgba(0, 224, 255, 0.08);

    /* --- Neon accents --- */
    --cyan:           #00e0ff;
    --cyan-mid:       #00b8d4;
    --cyan-dim:       rgba(0, 224, 255, 0.12);
    --cyan-glow:      rgba(0, 224, 255, 0.25);
    --cyan-bright:    #80f0ff;

    --magenta:        #e040fb;
    --magenta-dim:    rgba(224, 64, 251, 0.12);
    --magenta-glow:   rgba(224, 64, 251, 0.25);

    --amber:          #ffab00;
    --amber-dim:      rgba(255, 171, 0, 0.1);

    --green:          #00e676;
    --green-dim:      rgba(0, 230, 118, 0.12);

    --red:            #ff1744;
    --red-dim:        rgba(255, 23, 68, 0.12);

    /* --- Text --- */
    --text:           #c8d6e5;
    --text-dim:       #5a6a80;
    --text-bright:    #ecf0f5;
    --text-muted:     #3a4a60;

    /* --- Structural --- */
    --border:         rgba(0, 224, 255, 0.07);
    --border-hover:   rgba(0, 224, 255, 0.18);
    --radius-sm:      8px;
    --radius:         12px;
    --radius-lg:      16px;
    --radius-xl:      24px;
    --transition:     0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.4s cubic-bezier(0.4, 0, 0.2, 1);

    /* --- Sizing --- */
    --sidebar-w:      260px;
    --panel-w:        260px;
    --header-h:       52px;
    --footer-h:       32px;
    --chat-max-w:     820px;
}

/* ---- Reset ---- */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* ---- Base ---- */
html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'Segoe UI', 'Inter', 'Helvetica Neue', sans-serif;
    background: var(--bg-void);
    color: var(--text);
    font-size: 14px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ---- Animated Grid Background ---- */
#grid-bg {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
    background-image:
        linear-gradient(rgba(0, 224, 255, 0.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(0, 224, 255, 0.025) 1px, transparent 1px);
    background-size: 48px 48px;
    animation: gridDrift 20s linear infinite;
}

#grid-bg::after {
    content: '';
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse at 15% 50%, rgba(0, 224, 255, 0.04) 0%, transparent 55%),
        radial-gradient(ellipse at 85% 20%, rgba(224, 64, 251, 0.03) 0%, transparent 50%),
        radial-gradient(ellipse at 50% 80%, rgba(0, 230, 118, 0.015) 0%, transparent 40%);
}

@keyframes gridDrift {
    0%   { transform: translate(0, 0); }
    100% { transform: translate(48px, 48px); }
}

/* ---- Scanline Overlay ---- */
#app::before {
    content: '';
    position: fixed;
    inset: 0;
    z-index: 999;
    pointer-events: none;
    background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 2px,
        rgba(0, 0, 0, 0.02) 2px,
        rgba(0, 0, 0, 0.02) 4px
    );
}

/* ---- App Shell ---- */
#app {
    position: relative;
    z-index: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
}

/* ---- Header ---- */
header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: var(--header-h);
    padding: 0 20px;
    background: var(--glass-heavy);
    backdrop-filter: blur(24px) saturate(1.2);
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
    z-index: 10;
    position: relative;
}

header::after {
    content: '';
    position: absolute;
    bottom: -1px;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--cyan-dim), var(--magenta-dim), transparent);
}

.header-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

header h1 {
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 3px;
    text-transform: uppercase;
    background: linear-gradient(135deg, var(--cyan), var(--magenta));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.header-badge {
    font-size: 9px;
    font-weight: 700;
    letter-spacing: 2px;
    padding: 2px 6px;
    border: 1px solid var(--cyan-dim);
    border-radius: 4px;
    color: var(--cyan);
    background: var(--cyan-dim);
}

.icon-btn {
    background: none;
    border: 1px solid transparent;
    color: var(--text-dim);
    width: 34px;
    height: 34px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.icon-btn:hover {
    border-color: var(--border-hover);
    color: var(--cyan);
    background: var(--cyan-dim);
    box-shadow: 0 0 12px var(--cyan-dim);
}

.status-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--green);
    box-shadow: 0 0 6px var(--green), 0 0 12px rgba(0, 230, 118, 0.3);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50%      { opacity: 0.5; }
}

.mobile-only { display: none; }

/* ---- Main Layout ---- */
main {
    display: flex;
    flex: 1;
    overflow: hidden;
    min-height: 0;
}

/* ---- Sidebar ---- */
#sidebar {
    width: var(--sidebar-w);
    background: var(--glass-heavy);
    backdrop-filter: blur(20px);
    border-right: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    position: relative;
    z-index: 5;
    transition: var(--transition-slow);
}

#sidebar::after {
    content: '';
    position: absolute;
    top: 0;
    right: -1px;
    bottom: 0;
    width: 1px;
    background: linear-gradient(180deg, var(--cyan-dim), transparent 30%, transparent 70%, var(--magenta-dim));
}

.sidebar-header {
    padding: 16px 14px 12px;
}

#btn-new-chat {
    width: 100%;
    padding: 11px 16px;
    background: var(--cyan-dim);
    color: var(--cyan);
    border: 1px solid rgba(0, 224, 255, 0.12);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    font-family: inherit;
    letter-spacing: 0.5px;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 8px;
    justify-content: center;
}

#btn-new-chat:hover {
    background: rgba(0, 224, 255, 0.18);
    border-color: var(--cyan);
    box-shadow: 0 0 20px var(--cyan-dim), inset 0 0 20px var(--cyan-dim);
    transform: translateY(-1px);
}

#conversation-list {
    flex: 1;
    overflow-y: auto;
    padding: 0 10px 10px;
}

/* Scrollbar */
#conversation-list::-webkit-scrollbar { width: 4px; }
#conversation-list::-webkit-scrollbar-track { background: transparent; }
#conversation-list::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 2px; }

.conv-item {
    padding: 11px 14px;
    margin-bottom: 3px;
    cursor: pointer;
    border-radius: var(--radius-sm);
    font-size: 13px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    color: var(--text-dim);
    transition: var(--transition);
    position: relative;
    border: 1px solid transparent;
    display: flex;
    align-items: center;
    gap: 10px;
}

.conv-item::before {
    content: '';
    width: 5px;
    height: 5px;
    border-radius: 50%;
    background: var(--text-muted);
    flex-shrink: 0;
    transition: var(--transition);
}

.conv-item:hover {
    background: var(--bg-tertiary);
    color: var(--text);
    border-color: var(--border);
}

.conv-item:hover::before {
    background: var(--cyan);
    box-shadow: 0 0 6px var(--cyan-dim);
}

.conv-item.active {
    background: var(--cyan-dim);
    color: var(--cyan-bright);
    border-color: rgba(0, 224, 255, 0.15);
}

.conv-item.active::before {
    background: var(--cyan);
    box-shadow: 0 0 8px var(--cyan-glow);
}

.conv-item .title {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
}

.conv-item .delete-btn {
    opacity: 0;
    background: none;
    border: none;
    color: var(--text-dim);
    cursor: pointer;
    font-size: 12px;
    transition: var(--transition);
    padding: 2px 5px;
    border-radius: 4px;
    flex-shrink: 0;
    line-height: 1;
}

.conv-item:hover .delete-btn { opacity: 1; }
.conv-item .delete-btn:hover {
    color: var(--red);
    background: var(--red-dim);
}

/* ---- Chat Area ---- */
#chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    position: relative;
}

#messages {
    flex: 1;
    overflow-y: auto;
    padding: 32px 24px;
    scroll-behavior: smooth;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

#messages::-webkit-scrollbar { width: 5px; }
#messages::-webkit-scrollbar-track { background: transparent; }
#messages::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 3px; }

/* ---- Message Bubbles ---- */
.msg {
    max-width: var(--chat-max-w);
    width: 100%;
    padding: 14px 20px;
    border-radius: var(--radius-lg);
    font-size: 14px;
    line-height: 1.7;
    white-space: pre-wrap;
    word-break: break-word;
    position: relative;
    animation: msgIn 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

@keyframes msgIn {
    from {
        opacity: 0;
        transform: translateY(10px) scale(0.98);
        filter: blur(2px);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
        filter: blur(0);
    }
}

.msg.user {
    background: linear-gradient(135deg, rgba(0, 180, 216, 0.12), rgba(0, 224, 255, 0.06));
    border: 1px solid rgba(0, 224, 255, 0.1);
    border-radius: var(--radius-lg);
    color: var(--text-bright);
}

.msg.assistant {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    color: var(--text);
}

.msg.system {
    max-width: 600px;
    background: transparent;
    text-align: center;
    font-size: 12px;
    color: var(--text-dim);
    padding: 10px 20px;
    border: 1px dashed var(--border);
    border-radius: var(--radius);
    letter-spacing: 0.3px;
}

/* Typing cursor */
.msg .typing-cursor {
    display: inline-block;
    width: 2px;
    height: 16px;
    background: var(--cyan);
    margin-left: 2px;
    vertical-align: text-bottom;
    animation: cursorBlink 0.7s step-end infinite;
    box-shadow: 0 0 4px var(--cyan-dim);
}

@keyframes cursorBlink {
    0%, 100% { opacity: 1; }
    50%      { opacity: 0; }
}

/* ---- Empty State ---- */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    gap: 16px;
    opacity: 0;
    animation: fadeIn 0.6s 0.2s forwards;
}

@keyframes fadeIn {
    to { opacity: 1; }
}

.empty-icon {
    color: var(--text-muted);
    opacity: 0.35;
}

.empty-title {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 5px;
    background: linear-gradient(135deg, var(--cyan), var(--magenta));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.empty-sub {
    font-size: 13px;
    color: var(--text-dim);
    letter-spacing: 0.5px;
}

/* ---- Input Area ---- */
#input-area {
    padding: 16px 24px 14px;
    display: flex;
    flex-direction: column;
    align-items: center;
    flex-shrink: 0;
    position: relative;
}

#input-area::before {
    content: '';
    position: absolute;
    top: 0;
    left: 10%;
    right: 10%;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--cyan-dim), transparent);
}

.input-wrapper {
    display: flex;
    gap: 10px;
    align-items: flex-end;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: var(--radius-xl);
    padding: 6px 6px 6px 18px;
    transition: var(--transition);
    max-width: var(--chat-max-w);
    width: 100%;
}

.input-wrapper:focus-within {
    border-color: var(--cyan);
    box-shadow: 0 0 0 3px var(--cyan-dim), 0 0 30px var(--cyan-dim);
}

#user-input {
    flex: 1;
    resize: none;
    background: transparent;
    color: var(--text);
    border: none;
    padding: 10px 0;
    font-size: 14px;
    font-family: inherit;
    line-height: 1.5;
    max-height: 140px;
    outline: none;
}

#user-input::placeholder {
    color: var(--text-muted);
}

#btn-send {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--cyan-mid), var(--cyan));
    color: var(--bg-void);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    flex-shrink: 0;
}

#btn-send:hover:not(:disabled) {
    box-shadow: 0 0 20px var(--cyan-glow);
    transform: scale(1.05);
}

#btn-send:active:not(:disabled) {
    transform: scale(0.97);
}

#btn-send:disabled {
    opacity: 0.3;
    cursor: not-allowed;
    background: var(--bg-tertiary);
    color: var(--text-muted);
}

.input-hint {
    font-size: 11px;
    color: var(--text-muted);
    text-align: center;
    padding-top: 8px;
    letter-spacing: 0.3px;
}

/* ---- File Panel ---- */
#file-panel {
    width: var(--panel-w);
    background: var(--glass-heavy);
    backdrop-filter: blur(20px);
    border-left: 1px solid var(--border);
    display: none;
    flex-direction: column;
    flex-shrink: 0;
    position: relative;
    z-index: 5;
    transition: var(--transition-slow);
}

#file-panel.visible {
    display: flex;
}

#file-panel::after {
    content: '';
    position: absolute;
    top: 0;
    left: -1px;
    bottom: 0;
    width: 1px;
    background: linear-gradient(180deg, var(--magenta-dim), transparent 30%, transparent 70%, var(--cyan-dim));
}

.panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 16px 12px;
}

.panel-header h3 {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: var(--text-dim);
}

.upload-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    margin: 0 14px 12px;
    padding: 9px 14px;
    background: var(--bg-tertiary);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    font-family: inherit;
    font-weight: 500;
    letter-spacing: 0.4px;
    transition: var(--transition);
}

.upload-btn:hover {
    border-color: var(--border-hover);
    color: var(--cyan);
    background: var(--cyan-dim);
    box-shadow: 0 0 12px var(--cyan-dim);
}

#file-list {
    flex: 1;
    overflow-y: auto;
    padding: 0 14px;
}

#file-list::-webkit-scrollbar { width: 3px; }
#file-list::-webkit-scrollbar-track { background: transparent; }
#file-list::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 2px; }

.file-item {
    padding: 9px 12px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-radius: var(--radius-sm);
    font-size: 12px;
    color: var(--text-dim);
    transition: var(--transition);
    border: 1px solid transparent;
    margin-bottom: 3px;
}

.file-item:hover {
    background: var(--bg-tertiary);
    border-color: var(--border);
    color: var(--text);
}

.file-item .name {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    flex: 1;
    margin-right: 8px;
}

.file-item .del {
    background: none;
    border: none;
    color: var(--text-dim);
    cursor: pointer;
    opacity: 0;
    transition: var(--transition);
    font-size: 12px;
    padding: 2px 5px;
    border-radius: 4px;
    line-height: 1;
}

.file-item:hover .del { opacity: 1; }
.file-item .del:hover {
    color: var(--red);
    background: var(--red-dim);
}

.panel-divider {
    border: none;
    border-top: 1px solid var(--border);
    margin: 8px 14px;
}

/* ---- Status Bar / Footer ---- */
#status-bar {
    height: var(--footer-h);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 20px;
    background: var(--bg-secondary);
    border-top: 1px solid var(--border);
    font-size: 11px;
    color: var(--text-muted);
    letter-spacing: 0.5px;
    flex-shrink: 0;
    z-index: 10;
}

#status-text { color: var(--text-dim); }

/* ---- Modal ---- */
.modal {
    position: fixed;
    inset: 0;
    z-index: 100;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal.hidden { display: none; }

.modal-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.7);
    backdrop-filter: blur(8px);
    animation: fadeIn 0.2s ease-out;
}

.modal-content {
    position: relative;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    padding: 24px;
    border-radius: var(--radius-lg);
    width: 460px;
    max-width: 90vw;
    animation: modalIn 0.3s cubic-bezier(0.22, 1, 0.36, 1);
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.6), 0 0 0 1px var(--border);
}

@keyframes modalIn {
    from {
        opacity: 0;
        transform: translateY(16px) scale(0.97);
    }
    to {
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 18px;
}

.modal-header h3 {
    font-size: 14px;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--text-bright);
}

.modal-content textarea {
    width: 100%;
    background: var(--bg-tertiary);
    color: var(--text);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 14px;
    font-family: inherit;
    font-size: 13px;
    resize: vertical;
    outline: none;
    transition: var(--transition);
}

.modal-content textarea:focus {
    border-color: var(--magenta);
    box-shadow: 0 0 0 2px var(--magenta-dim);
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 18px;
}

.modal-actions button {
    padding: 9px 20px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 13px;
    font-weight: 600;
    font-family: inherit;
    letter-spacing: 0.4px;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 6px;
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text);
    border: 1px solid var(--border) !important;
}

.btn-secondary:hover {
    border-color: var(--border-hover) !important;
    color: var(--text-bright);
}

.btn-primary {
    background: linear-gradient(135deg, var(--magenta), #d53f8c);
    color: #fff;
}

.btn-primary:hover {
    box-shadow: 0 4px 20px var(--magenta-glow);
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
}

/* ---- Responsive ---- */
@media (max-width: 1024px) {
    #file-panel {
        position: fixed;
        right: 0;
        top: var(--header-h);
        bottom: var(--footer-h);
        z-index: 20;
        transform: translateX(100%);
        box-shadow: -8px 0 32px rgba(0, 0, 0, 0.4);
        display: flex;
    }

    #file-panel.visible {
        transform: translateX(0);
    }

    .mobile-only { display: flex; }
}

@media (max-width: 768px) {
    #sidebar {
        position: fixed;
        left: 0;
        top: var(--header-h);
        bottom: var(--footer-h);
        z-index: 20;
        transform: translateX(-100%);
        box-shadow: 8px 0 32px rgba(0, 0, 0, 0.4);
    }

    #sidebar.open {
        transform: translateX(0);
    }

    .mobile-only { display: flex; }

    .input-hint { display: none; }

    #messages {
        padding: 20px 16px;
    }

    .msg {
        max-width: 100%;
    }

    .input-wrapper {
        border-radius: var(--radius-lg);
        padding: 4px 4px 4px 14px;
    }
}

/* ---- Utility: Toast notification ---- */
.toast {
    position: fixed;
    bottom: calc(var(--footer-h) + 16px);
    left: 50%;
    transform: translateX(-50%) translateY(20px);
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    color: var(--text);
    padding: 10px 24px;
    border-radius: var(--radius);
    font-size: 13px;
    font-family: inherit;
    z-index: 200;
    opacity: 0;
    animation: toastIn 0.3s 0.05s forwards, toastOut 0.3s 2.5s forwards;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
}

.toast.error {
    border-color: rgba(255, 23, 68, 0.2);
    color: var(--red);
}

@keyframes toastIn {
    to {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
}

@keyframes toastOut {
    to {
        opacity: 0;
        transform: translateX(-50%) translateY(10px);
    }
}

/* ---- Model Selector ---- */
.model-select {
    background: var(--bg-tertiary);
    color: var(--cyan);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 4px 8px;
    font-size: 12px;
    font-family: inherit;
    cursor: pointer;
    outline: none;
    transition: var(--transition);
}

.model-select:hover,
.model-select:focus {
    border-color: var(--cyan);
    box-shadow: 0 0 8px var(--cyan-dim);
}

.model-select option {
    background: var(--bg-secondary);
    color: var(--text);
}

/* ---- Landing Page ---- */
#landing {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: var(--bg-void);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.landing-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 28px;
    animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

.landing-logo {
    position: relative;
    width: 130px;
    height: 130px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.logo-ring {
    position: absolute;
    inset: 0;
    border: 1px solid var(--cyan-dim);
    border-radius: 50%;
    animation: ringPulse 3s ease-in-out infinite;
}

.ring-2 {
    inset: 12px;
    border-color: var(--magenta-dim);
    animation-delay: 0.5s;
}

.ring-3 {
    inset: 24px;
    border-color: var(--cyan-dim);
    animation-delay: 1s;
}

@keyframes ringPulse {
    0%, 100% { opacity: 0.3; transform: scale(1); }
    50% { opacity: 0.8; transform: scale(1.05); }
}

.logo-text {
    font-size: 30px;
    font-weight: 700;
    letter-spacing: 6px;
    background: linear-gradient(135deg, var(--cyan), var(--magenta));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    z-index: 1;
}

.landing-title {
    font-size: 15px;
    font-weight: 400;
    letter-spacing: 5px;
    color: var(--text-dim);
    text-transform: uppercase;
}

.landing-sub {
    font-size: 13px;
    color: var(--text-muted);
    letter-spacing: 1px;
}

.landing-btn {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 13px 36px;
    background: transparent;
    color: var(--cyan);
    border: 1px solid var(--cyan);
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 14px;
    font-family: inherit;
    letter-spacing: 1px;
    transition: var(--transition);
    margin-top: 24px;
}

.landing-btn:hover {
    background: var(--cyan-dim);
    box-shadow: 0 0 30px var(--cyan-dim), inset 0 0 30px var(--cyan-dim);
    transform: translateX(4px);
}

.landing-footer {
    position: absolute;
    bottom: 28px;
    font-size: 11px;
    color: var(--text-muted);
    letter-spacing: 2px;
}

/* ---- Model Dropdown (input area) ---- */
.model-selector-wrap {
    position: relative;
}

.model-btn {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 7px 12px;
    background: var(--bg-tertiary);
    color: var(--cyan);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 12px;
    font-family: inherit;
    transition: var(--transition);
    white-space: nowrap;
}

.model-btn:hover {
    border-color: var(--cyan);
    box-shadow: 0 0 8px var(--cyan-dim);
}

.model-dropdown {
    position: absolute;
    bottom: calc(100% + 10px);
    left: 0;
    min-width: 200px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-hover);
    border-radius: var(--radius);
    padding: 5px;
    z-index: 50;
    box-shadow: 0 -8px 30px rgba(0, 0, 0, 0.4);
    animation: dropUp 0.15s ease-out;
}

@keyframes dropUp {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.model-option {
    padding: 9px 14px;
    font-size: 13px;
    color: var(--text-dim);
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}

.model-option:hover {
    background: var(--cyan-dim);
    color: var(--cyan);
}

.model-option.active {
    color: var(--cyan);
    background: var(--cyan-dim);
}

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

/* ---- Chat Header ---- */
.chat-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 20px;
    border-bottom: 1px solid var(--border);
    background: var(--glass);
    backdrop-filter: blur(12px);
    flex-shrink: 0;
    min-height: 40px;
}

.chat-header-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.chat-header .model-selector-wrap {
    position: relative;
}

.chat-header .model-dropdown {
    position: absolute;
    top: calc(100% + 6px);
    right: 0;
    min-width: 180px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-hover);
    border-radius: var(--radius);
    padding: 4px;
    z-index: 50;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.4);
}

.chat-header .model-btn {
    padding: 4px 10px;
    font-size: 11px;
}

/* ---- Conversation Actions ---- */
.conv-actions {
    position: absolute;
    right: 6px;
    top: 50%;
    transform: translateY(-50%);
    display: flex;
    gap: 2px;
    opacity: 0;
    transition: var(--transition);
}

.conv-item:hover .conv-actions { opacity: 1; }

.rename-btn, .delete-btn {
    background: none;
    border: none;
    color: var(--text-dim);
    cursor: pointer;
    font-size: 12px;
    padding: 2px 4px;
    border-radius: 3px;
    transition: var(--transition);
    line-height: 1;
}

.rename-btn:hover { color: var(--cyan); background: var(--cyan-dim); }
.delete-btn:hover { color: var(--red); background: var(--red-dim); }
.hidden { display: none !important; }

/* ---- Stop Button ---- */
#btn-send .icon-stop {
    color: var(--red);
}

#btn-send:has(.icon-stop:not(.hidden)):hover {
    background: var(--red-dim);
    border-color: var(--red);
}

/* ---- Message Edit Button ---- */
.msg-edit-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    background: var(--bg-tertiary);
    border: 1px solid var(--border);
    color: var(--text-dim);
    width: 28px;
    height: 28px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: var(--transition);
}

.msg.user:hover .msg-edit-btn {
    opacity: 1;
}

.msg-edit-btn:hover {
    color: var(--cyan);
    border-color: var(--cyan);
    background: var(--cyan-dim);
    box-shadow: 0 0 8px var(--cyan-dim);
}

/* ---- Long Message Truncation ---- */
.msg.user.truncated {
    max-height: 140px;
    overflow: hidden;
    position: relative;
}

.msg.user.truncated::after {
    content: '';
    position: absolute;
    bottom: 30px;
    left: 0;
    right: 0;
    height: 48px;
    background: linear-gradient(to bottom, transparent, rgba(0, 180, 216, 0.08));
    pointer-events: none;
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
}

.msg-expand-btn {
    display: block;
    width: calc(100% + 40px);
    margin: 8px -20px -14px;
    padding: 6px 0 4px;
    background: none;
    border: none;
    border-top: 1px solid var(--border);
    color: var(--cyan);
    font-size: 12px;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
    position: relative;
    z-index: 1;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
}

.msg-expand-btn:hover {
    color: var(--cyan-bright);
    background: var(--cyan-dim);
}

/* ---- Nexus Progress Panel ---- */
.nexus-panel {
    max-width: var(--chat-max-w);
    width: 100%;
    background: var(--bg-secondary);
    border: 1px solid rgba(255, 171, 0, 0.15);
    border-radius: var(--radius-lg);
    padding: 16px 20px;
    margin: 8px 0;
    animation: msgIn 0.35s cubic-bezier(0.22, 1, 0.36, 1);
}

.nexus-panel-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 12px;
}

.nexus-panel-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 600;
    color: var(--amber);
    letter-spacing: 0.5px;
}

.nexus-icon {
    font-size: 16px;
    animation: pulse 1.5s ease-in-out infinite;
}

.nexus-cancel-btn {
    display: flex;
    align-items: center;
    gap: 5px;
    padding: 5px 12px;
    background: var(--red-dim);
    border: 1px solid rgba(255, 23, 68, 0.2);
    color: var(--red);
    border-radius: var(--radius-sm);
    font-size: 11px;
    font-family: inherit;
    cursor: pointer;
    transition: var(--transition);
}

.nexus-cancel-btn:hover {
    background: rgba(255, 23, 68, 0.2);
    border-color: var(--red);
    box-shadow: 0 0 10px rgba(255, 23, 68, 0.15);
}

.nexus-task-desc {
    font-size: 12px;
    color: var(--text-dim);
    padding: 8px 12px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    margin-bottom: 12px;
    max-height: 60px;
    overflow: hidden;
    text-overflow: ellipsis;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

.nexus-steps {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.nexus-step {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 7px 10px;
    border-radius: var(--radius-sm);
    font-size: 12px;
    color: var(--text-dim);
    transition: var(--transition);
}

.nexus-step-running {
    background: var(--cyan-dim);
    color: var(--cyan);
}

.nexus-step-done {
    color: var(--green);
    opacity: 0.8;
}

.nexus-step-error {
    color: var(--red);
    background: var(--red-dim);
}

.step-icon {
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 11px;
}

.step-done {
    color: var(--green);
    font-weight: 700;
}

.step-error {
    color: var(--red);
    font-weight: 700;
}

.step-pending {
    color: var(--text-muted);
}

.step-spinner {
    width: 12px;
    height: 12px;
    border: 2px solid var(--cyan-dim);
    border-top-color: var(--cyan);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.step-desc {
    flex: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.nexus-output {
    margin-top: 8px;
    padding: 10px 12px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    font-size: 11px;
    color: var(--text-dim);
    max-height: 120px;
    overflow-y: auto;
    white-space: pre-wrap;
    word-break: break-word;
    line-height: 1.5;
    border: 1px solid var(--border);
}

.nexus-output::-webkit-scrollbar { width: 3px; }
.nexus-output::-webkit-scrollbar-track { background: transparent; }
.nexus-output::-webkit-scrollbar-thumb { background: var(--border-hover); border-radius: 2px; }

.nexus-complete {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 12px;
    margin-top: 8px;
    font-size: 12px;
    color: var(--green);
    font-weight: 600;
    background: var(--green-dim);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(0, 230, 118, 0.15);
}

.nexus-check {
    width: 18px;
    height: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--green);
    color: var(--bg-void);
    border-radius: 50%;
    font-size: 11px;
    font-weight: 700;
}