/* ChatGPT-Style Chat CSS - Clean and minimal */

/* Reset and base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: #f7f7f8;
    color: #2d2d2d;
}

/* App container */
.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    background: #ffffff;
}

/* Header - Minimal like ChatGPT */
.chat-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
    padding: 0.75rem;
    z-index: 100;
    display: flex;
    justify-content: center;
    align-items: center;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    max-width: 768px;
}

.header-content h1 {
    color: #2d2d2d;
    font-size: 1rem;
    font-weight: 600;
    margin: 0;
}

/* Language Selector */
.language-selector {
    display: flex;
    align-items: center;
}

.language-select {
    background: white;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 8px;
    padding: 0.375rem 0.75rem;
    font-size: 0.875rem;
    color: #2d2d2d;
    cursor: pointer;
    outline: none;
    transition: all 0.2s;
    appearance: none;
    background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 20 20'%3e%3cpath stroke='%236b7280' stroke-linecap='round' stroke-linejoin='round' stroke-width='1.5' d='m6 8 4 4 4-4'/%3e%3c/svg%3e");
    background-position: right 0.5rem center;
    background-repeat: no-repeat;
    background-size: 1rem;
    padding-right: 2.5rem;
    min-width: 140px;
    position: relative;
}

.language-select:hover {
    border-color: rgba(0, 0, 0, 0.2);
    background-color: #f7f7f8;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.language-select:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.1);
}

/* Language selector with voice status */
.language-selector {
    position: relative;
    display: flex;
    align-items: center;
}

.language-selector::after {
    content: '';
    position: absolute;
    top: 50%;
    right: 2rem;
    transform: translateY(-50%);
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #28a745;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.language-selector.voice-available::after {
    opacity: 1;
}

.language-selector.voice-unavailable::after {
    background: #dc3545;
    opacity: 1;
}

/* Main chat area - ChatGPT style */
.chat-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    width: 100%;
    max-width: 100%;
    margin: 0;
    padding: 60px 1rem 1rem;
    overflow: hidden;
}

/* Suggestions - Hidden by default, show when no messages */
.suggestions-container {
    display: none;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    margin: auto 0;
    padding: 2rem 0;
}

.suggestions-container:not(:empty) {
    display: grid;
}

/* Hide suggestions when there are messages */
.chat-messages:not(:empty) ~ .suggestions-container {
    display: none;
}

.suggestion-card {
    background: white;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 12px;
    padding: 1rem;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.suggestion-card:hover {
    background: #f7f7f8;
    border-color: rgba(0, 0, 0, 0.2);
}

.suggestion-card h4 {
    color: #2d2d2d;
    font-size: 0.875rem;
    margin: 0;
    font-weight: 500;
}

.suggestion-card p {
    display: none;
}

/* Chat messages - ChatGPT style */
.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 0;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

/* Show welcome when empty */
.chat-messages:empty::before {
    content: "How can I help you today?";
    display: block;
    text-align: center;
    font-size: 2rem;
    color: #2d2d2d;
    margin: auto;
    padding: 2rem;
    font-weight: 600;
}

.message {
    display: flex;
    padding: 1.5rem 0;
    animation: fadeIn 0.3s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Alternate background for messages */
.message:nth-child(even) {
    background: #f7f7f8;
}

.message.user {
    background: #f7f7f8;
}

.message-avatar {
    width: 30px;
    height: 30px;
    border-radius: 2px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 0.875rem;
    flex-shrink: 0;
    margin-right: 1rem;
    background: #19c37d;
}

.message.user .message-avatar {
    background: #5436da;
}

.message-content {
    flex: 1;
    line-height: 1.6;
    font-size: 1rem;
    max-width: none;
}

.message-content p {
    margin-bottom: 1rem;
}

.message-content p:last-child {
    margin-bottom: 0;
}

/* Confidence indicator - Now visible in bottom right */
.confidence-indicator {
    opacity: 0.7;
    transition: opacity 0.2s;
}

.message:hover .confidence-indicator {
    opacity: 1;
}

/* Typing indicator - ChatGPT style */
.typing-dots {
    display: flex;
    gap: 4px;
    padding: 0 1rem;
}

.typing-dots span {
    width: 8px;
    height: 8px;
    background: #2d2d2d;
    border-radius: 50%;
    animation: typing 1.4s infinite;
}

.typing-dots span:nth-child(2) {
    animation-delay: 0.2s;
}

.typing-dots span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing {
    0%, 60%, 100% { opacity: 0.2; }
    30% { opacity: 1; }
}

/* Options for clarification - ChatGPT style */
.clarification-message {
    margin-bottom: 1rem;
    color: #2d2d2d;
}

.option-card {
    background: white;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 12px;
    padding: 1rem;
    margin-bottom: 0.5rem;
    cursor: pointer;
    transition: all 0.2s;
}

.option-card:hover {
    background: #f7f7f8;
    border-color: rgba(0, 0, 0, 0.2);
}

.option-number {
    display: none;
}

.option-content {
    flex: 1;
}

.option-content .confidence {
    display: none;
}

/* Other option styling */
.option-card.option-other {
    background: #f8f9fa;
    border: 1px dashed rgba(0, 0, 0, 0.2);
    color: #666;
}

.option-card.option-other:hover {
    background: #e9ecef;
    border-color: rgba(0, 0, 0, 0.3);
}

/* Options container */
.options-container {
    margin-bottom: 1rem;
}

/* Input area - ChatGPT style */
.chat-input-container {
    position: relative;
    width: 100%;
    max-width: 100%;
    margin: 0 0 2rem;
    background: white;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 12px;
    padding: 0.75rem 1rem;
    display: flex;
    align-items: flex-end;
    gap: 0.75rem;
    box-shadow: 0 0 15px rgba(0, 0, 0, 0.1);
}

/* Voice Controls - Modern Design */
.chat-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.voice-controls {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Modern Voice Button */
.voice-button {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

.voice-button:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.voice-button:active {
    transform: scale(0.95);
}

/* Recording State Animation */
.voice-button.recording {
    background: linear-gradient(135deg, #ff6b6b 0%, #ee5a24 100%);
    animation: recordingPulse 1.5s ease-in-out infinite;
}

.voice-button.processing {
    background: linear-gradient(135deg, #74b9ff 0%, #0984e3 100%);
    animation: processingPulse 1s ease-in-out infinite;
}

.voice-button.success {
    background: linear-gradient(135deg, #00b894 0%, #00a085 100%);
    animation: successPulse 0.6s ease-out;
}

@keyframes recordingPulse {
    0%, 100% { 
        transform: scale(1); 
        box-shadow: 0 0 0 0 rgba(255, 107, 107, 0.7);
    }
    50% { 
        transform: scale(1.05); 
        box-shadow: 0 0 0 10px rgba(255, 107, 107, 0);
    }
}

@keyframes processingPulse {
    0%, 100% { 
        transform: scale(1); 
        opacity: 1;
    }
    50% { 
        transform: scale(1.02); 
        opacity: 0.8;
    }
}

@keyframes successPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.1); }
    100% { transform: scale(1); }
}

/* Auto Mode Toggle - Modern Switch */
.auto-mode-button {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.75rem;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 20px;
    background: white;
    color: #666;
    cursor: pointer;
    font-size: 0.875rem;
    font-weight: 500;
    transition: all 0.2s ease;
}

.auto-mode-button:hover {
    border-color: rgba(0, 0, 0, 0.2);
    background: #f8f9fa;
}

.auto-mode-button.active {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-color: transparent;
}

.auto-mode-button .auto-icon {
    width: 16px;
    height: 16px;
    fill: currentColor;
}

/* Language Selector in Voice Controls (Hidden - using header selector) */
.voice-controls .language-selector {
    display: none;
}

/* Voice Status Indicators */
.voice-status {
    display: flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.75rem;
    color: #666;
    margin-left: 0.5rem;
    opacity: 0;
    transition: opacity 0.2s ease;
}

.voice-status.visible {
    opacity: 1;
}

.voice-status .status-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: #28a745;
    transition: background-color 0.2s ease;
}

.voice-status.recording .status-dot {
    background: #dc3545;
    animation: recordingDot 1s ease-in-out infinite;
}

.voice-status.processing .status-dot {
    background: #007bff;
    animation: processingDot 1s ease-in-out infinite;
}

@keyframes recordingDot {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.3; }
}

@keyframes processingDot {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.2); }
}

/* Voice Feature Tooltips */
.voice-tooltip {
    position: relative;
}

.voice-tooltip::before {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: #2d2d2d;
    color: white;
    padding: 0.5rem 0.75rem;
    border-radius: 6px;
    font-size: 0.75rem;
    white-space: nowrap;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
    margin-bottom: 0.5rem;
    z-index: 1000;
}

.voice-tooltip::after {
    content: '';
    position: absolute;
    bottom: 100%;
    left: 50%;
    transform: translateX(-50%);
    border: 4px solid transparent;
    border-top-color: #2d2d2d;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.2s ease;
    margin-bottom: 0.1rem;
}

.voice-tooltip:hover::before,
.voice-tooltip:hover::after {
    opacity: 1;
}

/* First-time user guidance */
.voice-onboarding {
    position: fixed;
    bottom: 100px;
    right: 20px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 1rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(102, 126, 234, 0.3);
    max-width: 280px;
    opacity: 0;
    transform: translateX(100%);
    transition: all 0.3s ease;
    z-index: 1000;
}

.voice-onboarding.visible {
    opacity: 1;
    transform: translateX(0);
}

.voice-onboarding h4 {
    margin: 0 0 0.5rem 0;
    font-size: 0.875rem;
    font-weight: 600;
}

.voice-onboarding p {
    margin: 0 0 0.75rem 0;
    font-size: 0.75rem;
    line-height: 1.4;
}

.voice-onboarding-close {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.voice-onboarding-close:hover {
    background: rgba(255, 255, 255, 0.3);
}

.chat-input {
    flex: 1;
    border: none;
    outline: none;
    resize: none;
    font-family: inherit;
    font-size: 1rem;
    line-height: 1.5;
    max-height: 200px;
    color: #2d2d2d;
    background: transparent;
}

.chat-input::placeholder {
    color: #8e8ea0;
}

.send-button {
    background: #2d2d2d;
    color: white;
    border: none;
    border-radius: 8px;
    width: 32px;
    height: 32px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.2s;
    padding: 0;
}

.send-button:hover {
    opacity: 0.8;
}

.send-button:disabled {
    opacity: 0.4;
    cursor: not-allowed;
}

/* Send icon */
.send-button::before {
    content: "↑";
    font-size: 18px;
    font-weight: bold;
}

/* Scrollbar - minimal */
.chat-messages::-webkit-scrollbar {
    width: 0;
}

/* Mobile responsive - Clean ChatGPT style */
@media (max-width: 768px) {
    .chat-header {
        padding: 0.5rem;
        position: sticky;
        top: 0;
    }
    
    .header-content {
        flex-direction: row;
        gap: 0.5rem;
        align-items: center;
        justify-content: space-between;
    }
    
    .header-content h1 {
        font-size: 0.875rem;
        white-space: nowrap;
        overflow: hidden;
        text-overflow: ellipsis;
        max-width: 50%;
    }
    
    .language-select {
        min-width: 100px;
        padding: 0.25rem 0.5rem;
        padding-right: 2rem;
        font-size: 0.75rem;
    }
    
    .chat-main {
        padding: 70px 0.5rem 0.5rem;
    }
    
    .chat-messages {
        padding: 0.5rem;
    }
    
    .chat-messages:empty::before {
        font-size: 1.25rem;
        padding: 1rem;
        text-align: center;
    }
    
    .message {
        padding: 1rem 0.5rem;
    }
    
    .message-content {
        font-size: 0.9375rem;
    }
    
    /* Input area - fixed at bottom */
    .input-area {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        background: white;
        border-top: 1px solid rgba(0, 0, 0, 0.1);
        padding: 0.5rem;
    }
    
    .chat-input-container {
        margin: 0;
        border-radius: 8px;
        padding: 0.5rem;
        gap: 0.5rem;
        box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
    }
    
    .chat-input {
        font-size: 0.9375rem;
        min-height: 40px;
    }
    
    .send-button {
        min-width: 40px;
        width: 40px;
        height: 40px;
        flex-shrink: 0;
    }
    
    /* Mobile Voice Controls */
    .chat-controls {
        display: flex;
        align-items: center;
        gap: 0.25rem;
    }
    
    .voice-button {
        width: 40px;
        height: 40px;
        flex-shrink: 0;
    }
    
    .auto-mode-button {
        display: none; /* Hide on mobile to save space */
    }
    
    .voice-status {
        display: none; /* Hide on mobile to save space */
    }
    
    /* Adjust main chat area for fixed input */
    .chat-main {
        padding-bottom: 100px;
    }
    
    /* Suggestion cards - responsive grid */
    .suggestions-container {
        grid-template-columns: 1fr;
        gap: 0.5rem;
        padding: 1rem 0.5rem;
    }
    
    .suggestion-card {
        padding: 0.75rem;
        font-size: 0.875rem;
    }
    
    /* Option cards - full width on mobile */
    .option-card {
        margin: 0.5rem 0;
        padding: 0.75rem;
        font-size: 0.875rem;
    }
    
    /* Voice onboarding - adjust position */
    .voice-onboarding {
        bottom: 120px;
        right: 10px;
        left: 10px;
        max-width: none;
    }
}

/* Extra small screens */
@media (max-width: 480px) {
    .header-content h1 {
        font-size: 0.75rem;
        max-width: 45%;
    }
    
    .language-select {
        min-width: 90px;
        font-size: 0.7rem;
        padding: 0.2rem 0.4rem;
        padding-right: 1.5rem;
    }
    
    .chat-messages:empty::before {
        font-size: 1rem;
    }
    
    .message-avatar {
        width: 24px;
        height: 24px;
        font-size: 0.75rem;
        margin-right: 0.5rem;
    }
    
    .message-content {
        font-size: 0.875rem;
    }
    
    .confidence-indicator {
        font-size: 10px;
    }
    
    /* Even smaller voice controls */
    .voice-button {
        width: 36px;
        height: 36px;
    }
    
    .voice-button svg {
        width: 16px;
        height: 16px;
    }
}

/* Landscape mode on mobile */
@media (max-height: 600px) and (orientation: landscape) {
    .chat-header {
        padding: 0.25rem 0.5rem;
    }
    
    .header-content h1 {
        font-size: 0.75rem;
    }
    
    .chat-main {
        padding-top: 50px;
        padding-bottom: 80px;
    }
    
    .chat-messages:empty::before {
        font-size: 1rem;
        padding: 0.5rem;
    }
    
    .input-area {
        padding: 0.25rem 0.5rem;
    }
    
    .chat-input-container {
        padding: 0.375rem 0.5rem;
    }
    
    .chat-input {
        min-height: 32px;
        font-size: 0.875rem;
    }
    
    .send-button,
    .voice-button {
        width: 32px;
        height: 32px;
    }
}
/* Confidence Indicator */
.confidence-indicator {
    position: absolute;
    bottom: 5px;
    right: 10px;
    font-size: 11px;
    color: #999;
    background: rgba(255, 255, 255, 0.9);
    padding: 2px 6px;
    border-radius: 10px;
}

.message-content {
    position: relative;
    padding-bottom: 20px; /* Make room for confidence */
}

.confidence-value {
    font-weight: 500;
}

/* Confidence color coding */
.message[data-confidence="high"] .confidence-value {
    color: #28a745; /* Green for 90%+ */
}

.message[data-confidence="medium"] .confidence-value {
    color: #ffa500; /* Orange for 75-90% */
}

.message[data-confidence="low"] .confidence-value {
    color: #dc3545; /* Red for <75% */
}

/* Specific fixes for chat-embedded.html view with sidebar */
.chat-embedded-view .app-container {
    display: flex;
    flex-direction: row !important; /* Sidebar and chat side by side */
    height: 100vh;
    background: #f7f7f8;
}

.chat-embedded-view .chat-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    height: 100vh;
    overflow: hidden;
    position: relative;
    background: #ffffff;
}

/* Header removed for embedded view */

.chat-embedded-view .chat-main {
    padding: 2rem !important; /* Full height without header */
    flex: 1;
    overflow-y: auto;
    background: #f7f7f8;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.chat-embedded-view .sidebar {
    display: flex !important;
    flex-direction: column !important;
    width: 260px !important;
    flex-shrink: 0 !important;
    background: #ffffff;
    border-right: 1px solid rgba(0, 0, 0, 0.1);
    height: 100vh;
}

.chat-embedded-view .nav-menu {
    flex: 1;
    overflow-y: auto;
}

.chat-embedded-view .sidebar-footer {
    margin-top: auto;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
    padding: 0.5rem;
}

/* Ensure navigation items are visible and match standard styling */
.chat-embedded-view .nav-item {
    display: block !important;
    margin: 0;
}

.chat-embedded-view .nav-link {
    display: flex !important;
    align-items: center;
    padding: 0.75rem 1rem;
    color: #2d3748;
    text-decoration: none;
    transition: all 0.2s ease;
    border-radius: 6px;
    margin: 0.125rem 0;
}

.chat-embedded-view .nav-link:hover {
    background: #f3f4f6;
    color: #0066cc;
}

.chat-embedded-view .nav-link.active {
    background: #0066cc;
    color: #ffffff;
    font-weight: 600;
}

/* Ensure nav sections have proper spacing */
.chat-embedded-view .nav-section {
    margin-bottom: 1rem;
}

.chat-embedded-view .nav-section-title {
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    color: #6b7280;
    padding: 0.5rem 1rem;
    margin-bottom: 0.25rem;
}

.chat-embedded-view .nav-icon {
    margin-right: 0.75rem;
    font-size: 1.125rem;
}

.chat-embedded-view .input-area {
    position: relative;
    width: 100%;
    padding: 1rem;
    background: white;
    border-top: 1px solid rgba(0, 0, 0, 0.1);
}

.chat-embedded-view .chat-input-container {
    width: 100% !important;
    max-width: 900px !important;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Language selector in input area */
.chat-embedded-view .language-selector {
    flex-shrink: 0;
}

.chat-embedded-view .language-select {
    padding: 0.5rem;
    border: 1px solid rgba(0, 0, 0, 0.1);
    border-radius: 8px;
    background: white;
    font-size: 0.875rem;
    cursor: pointer;
    min-width: 120px;
}

/* Fix send button width */
.chat-embedded-view .send-button {
    flex-shrink: 0;
    padding: 0.5rem 1.5rem;
    min-width: 80px;
}

/* Chat input takes remaining space */
.chat-embedded-view .chat-input {
    flex: 1;
    resize: none;
    border: none;
    outline: none;
    padding: 0.5rem;
    font-size: 1rem;
    min-height: 40px;
    max-height: 120px;
}

/* Ensure suggestions container is properly displayed */
.chat-embedded-view .suggestions-container {
    max-width: 900px;
    width: 100%;
    margin: 0 auto;
    display: none; /* Hidden by default */
}

.chat-embedded-view .suggestions-container:not(:empty) {
    display: grid !important; /* Show when has content */
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1rem;
    padding: 2rem 0;
}

/* Ensure chat messages are properly centered */
.chat-embedded-view .chat-messages {
    max-width: 900px;
    width: 100%;
    margin: 0 auto;
}

/* Show suggestions only when chat is empty */
.chat-embedded-view .chat-main:has(.chat-messages:empty) .suggestions-container:not(:empty) {
    display: grid !important;
}

/* Mobile responsive for embedded view */
@media (max-width: 768px) {
    .chat-embedded-view .sidebar {
        position: fixed;
        left: -260px;
        height: 100vh;
        z-index: 1000;
        transition: left 0.3s ease;
    }
    
    .chat-embedded-view .sidebar.active {
        left: 0;
    }
    
    .chat-embedded-view .menu-toggle {
        display: block !important;
        position: fixed;
        top: 1rem;
        left: 1rem;
        z-index: 1001;
        background: white;
        border: 1px solid rgba(0, 0, 0, 0.1);
        border-radius: 8px;
        padding: 0.5rem;
        cursor: pointer;
    }
    
    .chat-embedded-view .chat-container {
        width: 100%;
    }
}
EOF < /dev/null