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

:root {
    --primary-color: #50b5ff;
    --primary-dark: #3a9de0;
    --secondary-color: #d592ff;
    --bg-primary: #ffffff;
    --bg-secondary: #f8f9fa;
    --bg-tertiary: #f1f3f5;
    --text-primary: #1a1a1a;
    --text-secondary: #6b7280;
    --text-tertiary: #9ca3af;
    --border-color: #e5e7eb;
    --border-radius: 12px;
    --border-radius-sm: 8px;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --spacing-xs: 0.5rem;
    --spacing-sm: 0.75rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* App Container */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    max-width: 1200px;
    margin: 0 auto;
    background: var(--bg-primary);
    box-shadow: var(--shadow-lg);
}

/* For chat interface (index.html), use fixed height */
.app-container.chat-layout {
    height: 100vh;
    overflow: hidden;
}

/* Header */
.app-header {
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-primary);
    padding: var(--spacing-md) var(--spacing-lg);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-left {
    flex: 1;
}

.header-actions {
    display: flex;
    gap: var(--spacing-xs);
    align-items: center;
}

.app-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 0.25rem;
}

.app-subtitle {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 400;
}

.btn-icon {
    background: transparent;
    border: none;
    padding: var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.btn-icon:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-nav {
    background: transparent;
    border: none;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    transition: all 0.2s ease;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    white-space: nowrap;
}

.btn-nav:hover {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

.btn-nav svg {
    flex-shrink: 0;
}

.btn-nav-text {
    display: inline-block;
}

.btn-logout {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    border: 1.5px solid var(--border-color);
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--border-radius-sm);
    cursor: pointer;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    font-size: 0.875rem;
    font-weight: 600;
    transition: all 0.2s ease;
    font-family: inherit;
    min-width: 90px;
    box-shadow: var(--shadow-sm);
}

.btn-logout:hover {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    color: var(--primary-color);
    border-color: var(--primary-color);
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.btn-logout:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.btn-logout svg {
    flex-shrink: 0;
    transition: transform 0.2s ease;
}

.btn-logout:hover svg {
    transform: translateX(2px);
}

.btn-logout svg {
    flex-shrink: 0;
}

/* Main Content */
.app-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* Chat Container */
.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: var(--spacing-lg);
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.chat-container::-webkit-scrollbar {
    width: 8px;
}

.chat-container::-webkit-scrollbar-track {
    background: transparent;
}

.chat-container::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 4px;
}

.chat-container::-webkit-scrollbar-thumb:hover {
    background: var(--text-tertiary);
}

/* Messages */
.message {
    display: flex;
    gap: var(--spacing-md);
    animation: fadeIn 0.3s ease;
}

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

.message-user {
    flex-direction: row-reverse;
}

.message-assistant {
    flex-direction: row;
}

.message-avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    background: var(--bg-tertiary);
    color: var(--text-secondary);
}

.message-user .message-avatar {
    background: var(--primary-color);
    color: white;
}

.message-assistant .message-avatar {
    background: var(--bg-tertiary);
    color: var(--primary-color);
}

.message-content {
    flex: 1;
    max-width: 75%;
    min-width: 0;
}

.message-text {
    background: var(--bg-secondary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    color: var(--text-primary);
    word-wrap: break-word;
    line-height: 1.6;
}

.message-user .message-text {
    background: var(--primary-color);
    color: white;
    border-bottom-right-radius: 4px;
}

.message-assistant .message-text {
    background: var(--bg-secondary);
    border-bottom-left-radius: 4px;
}

.message-text h3 {
    font-size: 1.125rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
    color: inherit;
}

.message-text p {
    margin-bottom: var(--spacing-sm);
    color: inherit;
}

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

.message-text ul {
    margin-left: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    color: inherit;
}

.message-text li {
    margin-bottom: var(--spacing-xs);
    color: inherit;
}

.message-text code {
    background: rgba(0, 0, 0, 0.1);
    padding: 0.125rem 0.25rem;
    border-radius: 4px;
    font-family: 'Courier New', monospace;
    font-size: 0.875em;
}

.message-user .message-text code {
    background: rgba(255, 255, 255, 0.2);
}

.message-time {
    font-size: 0.75rem;
    color: var(--text-tertiary);
    margin-top: var(--spacing-xs);
    padding-left: var(--spacing-sm);
}

.message-user .message-time {
    text-align: right;
    padding-right: var(--spacing-sm);
    padding-left: 0;
}

.welcome-message .message-text {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: var(--spacing-lg);
}

.welcome-message .message-text h3 {
    color: white;
}

.welcome-message .message-text p,
.welcome-message .message-text li {
    color: rgba(255, 255, 255, 0.95);
}

/* Input Container */
.input-container {
    border-top: 1px solid var(--border-color);
    background: var(--bg-primary);
    padding: var(--spacing-md) var(--spacing-lg);
}

.input-wrapper {
    display: flex;
    gap: var(--spacing-sm);
    align-items: flex-end;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: var(--spacing-sm);
    transition: all 0.2s ease;
}

.input-wrapper:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(80, 181, 255, 0.1);
}

.message-input {
    flex: 1;
    border: none;
    background: transparent;
    resize: none;
    font-family: inherit;
    font-size: 0.9375rem;
    color: var(--text-primary);
    padding: var(--spacing-sm);
    max-height: 150px;
    overflow-y: auto;
    line-height: 1.5;
}

.message-input:focus {
    outline: none;
}

.message-input::placeholder {
    color: var(--text-tertiary);
}

.btn-send {
    background: var(--primary-color);
    border: none;
    color: white;
    width: 40px;
    height: 40px;
    border-radius: var(--border-radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    flex-shrink: 0;
}

.btn-send:hover:not(:disabled) {
    background: var(--primary-dark);
    transform: scale(1.05);
}

.btn-send:active:not(:disabled) {
    transform: scale(0.95);
}

.btn-send:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.input-footer {
    margin-top: var(--spacing-xs);
    padding-left: var(--spacing-sm);
}

.input-hint {
    font-size: 0.75rem;
    color: var(--text-tertiary);
}

/* Loading Indicator */
.loading-indicator {
    position: fixed;
    bottom: 100px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--bg-primary);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    z-index: 1000;
}

.loading-dots {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.loading-dots span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--primary-color);
    animation: bounce 1.4s infinite ease-in-out both;
}

.loading-dots span:nth-child(1) {
    animation-delay: -0.32s;
}

.loading-dots span:nth-child(2) {
    animation-delay: -0.16s;
}

@keyframes bounce {
    0%, 80%, 100% {
        transform: scale(0);
        opacity: 0.5;
    }
    40% {
        transform: scale(1);
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 1024px) {
    .header-content {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }

    .header-actions {
        flex-wrap: wrap;
        gap: var(--spacing-xs);
    }

    .btn-nav-text {
        display: none;
    }

    .btn-nav {
        padding: var(--spacing-sm);
    }

    .btn-logout span {
        display: none;
    }

    .btn-logout {
        min-width: auto;
        padding: var(--spacing-sm);
    }
}

@media (max-width: 768px) {
    .app-container {
        height: 100vh;
        max-width: 100%;
    }

    .app-header {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .header-content {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }

    .header-left {
        width: 100%;
    }

    .header-actions {
        width: 100%;
        justify-content: flex-start;
        flex-wrap: wrap;
        gap: var(--spacing-xs);
    }

    .app-title {
        font-size: 1.25rem;
    }

    .app-subtitle {
        font-size: 0.8125rem;
    }

    .btn-nav {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: 0.8125rem;
    }

    .chat-container {
        padding: var(--spacing-md);
        gap: var(--spacing-md);
    }

    .message-content {
        max-width: 85%;
    }

    .input-container {
        padding: var(--spacing-sm) var(--spacing-md);
    }

    .message-input {
        font-size: 16px; /* Prevents zoom on iOS */
    }

    .message-input::placeholder {
        font-size: 0.875rem;
    }
}

@media (max-width: 480px) {
    .app-header {
        padding: var(--spacing-xs) var(--spacing-sm);
    }

    .header-actions {
        gap: 0.25rem;
    }

    .btn-nav {
        padding: var(--spacing-xs);
        min-width: 40px;
    }

    .input-container {
        padding: var(--spacing-xs) var(--spacing-sm);
    }

    .input-wrapper {
        padding: var(--spacing-xs);
    }

    .message-input {
        font-size: 14px;
        padding: var(--spacing-xs);
    }

    .message-input::placeholder {
        font-size: 0.75rem;
    }

    .btn-logout {
        padding: var(--spacing-xs);
        min-width: 40px;
    }

    .app-title {
        font-size: 1.125rem;
    }

    .app-subtitle {
        font-size: 0.75rem;
    }

    .chat-container {
        padding: var(--spacing-sm);
    }

    .message-content {
        max-width: 90%;
    }

    .input-container {
        padding: var(--spacing-xs) var(--spacing-sm);
    }

    .input-wrapper {
        padding: var(--spacing-xs);
    }

    .message-input {
        font-size: 14px;
        padding: var(--spacing-xs);
    }

    .message-input::placeholder {
        font-size: 0.75rem;
    }
}

/* Typing Animation */
.typing-indicator {
    display: inline-flex;
    gap: 4px;
    padding: var(--spacing-sm) 0;
}

.typing-indicator span {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--text-secondary);
    animation: typing 1.4s infinite ease-in-out;
}

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

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

@keyframes typing {
    0%, 60%, 100% {
        transform: translateY(0);
        opacity: 0.7;
    }
    30% {
        transform: translateY(-10px);
        opacity: 1;
    }
}