/* Apple-inspired Design System */
:root {
    --primary-color: #007AFF;
    --secondary-color: #5856D6;
    --background-color: #F2F2F7;
    --surface-color: #FFFFFF;
    --text-primary: #000000;
    --text-secondary: #8E8E93;
    --border-color: #C6C6C8;
    --shadow-light: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 12px rgba(0, 0, 0, 0.1);
    --shadow-heavy: 0 8px 24px rgba(0, 0, 0, 0.12);
    --radius-small: 8px;
    --radius-medium: 12px;
    --radius-large: 20px;
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-smooth: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-primary);
    height: 100vh;
    overflow: hidden;
}

.app-container {
    display: flex;
    flex-direction: column;
    height: 100vh;
    max-width: 900px;
    margin: 0 auto;
    background-color: var(--surface-color);
    box-shadow: var(--shadow-heavy);
}

/* Header */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 1rem 1.5rem;
    box-shadow: var(--shadow-medium);
    z-index: 100;
}

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

.header-left {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.header-left i {
    font-size: 1.5rem;
}

.header h1 {
    font-size: 1.25rem;
    font-weight: 600;
}

.header-right {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.anycoder-link {
    color: white;
    text-decoration: none;
    font-size: 0.875rem;
    opacity: 0.9;
    transition: opacity var(--transition-fast);
}

.anycoder-link:hover {
    opacity: 1;
    text-decoration: underline;
}

.model-status {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.25rem 0.75rem;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    font-size: 0.875rem;
}

.status-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #FF3B30;
}

.status-dot.loading {
    background: #FF9500;
    animation: pulse 1.5s infinite;
}

.status-dot.ready {
    background: #34C759;
}

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

/* Chat Container */
.chat-container {
    flex: 1;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    position: relative;
}

.chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 1.5rem;
    scroll-behavior: smooth;
}

.chat-messages::-webkit-scrollbar {
    width: 4px;
}

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

.chat-messages::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 2px;
}

/* Messages */
.message {
    margin-bottom: 1.5rem;
    opacity: 0;
    transform: translateY(10px);
    transition: all var(--transition-smooth);
}

.message.system {
    text-align: center;
}

.message.system .message-content {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    background: var(--background-color);
    border-radius: var(--radius-large);
    color: var(--text-secondary);
    font-size: 0.875rem;
}

.message.system i {
    margin-right: 0.5rem;
    color: var(--primary-color);
}

.message.user .message-content {
    display: flex;
    justify-content: flex-end;
    gap: 0.75rem;
}

.message.assistant .message-content {
    display: flex;
    gap: 0.75rem;
}

.avatar {
    width: 36px;
    height: 36px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 1rem;
}

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

.avatar:not(.user) {
    background: var(--background-color);
    color: var(--text-secondary);
}

.message-content-inner {
    max-width: 70%;
}

.message-role {
    font-size: 0.75rem;
    color: var(--text-secondary);
    margin-bottom: 0.25rem;
    font-weight: 500;
}

.message-text {
    padding: 0.75rem 1rem;
    background: var(--background-color);
    border-radius: var(--radius-medium);
    line-height: 1.5;
    word-wrap: break-word;
}

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

.message.error .message-text {
    background: #FF3B30;
    color: white;
}

/* Typing Indicator */
.typing-indicator {
    padding: 0 1.5rem 1.5rem;
}

.typing-dots {
    display: flex;
    gap: 0.25rem;
    padding: 0.75rem 1rem;
}

.typing-dots span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--text-secondary);
    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% {
        transform: translateY(0);
        opacity: 0.5;
    }
    30% {
        transform: translateY(-10px);
        opacity: 1;
    }
}

/* Input Container */
.input-container {
    background: var(--surface-color);
    border-top: 1px solid var(--border-color);
    padding: 1rem 1.5rem;
}

.input-wrapper {
    max-width: 100%;
}

.input-group {
    display: flex;
    gap: 0.75rem;
    align-items: flex-end;
}

#messageInput {
    flex: 1;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-medium);
    font-size: 1rem;
    font-family: inherit;
    resize: none;
    outline: none;
    transition: all var(--transition-fast);
    background: var(--background-color);
    min-height: 44px;
    max-height: 120px;
}

#messageInput:focus {
    border-color: var(--primary-color);
    background: var(--surface-color);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1);
}

.send-button {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background: var(--primary-color);
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-fast);
    font-size: 1rem;
}

.send-button:hover:not(:disabled) {
    background: #0056CC;
    transform: scale(1.05);
}

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

.send-button:disabled {
    background: var(--border-color);
    cursor: not-allowed;
    opacity: 0.6;
}

.input-info {
    margin-top: 0.5rem;
    text-align: right;
}

#charCount {
    font-size: 0.75rem;
    color: var(--text-secondary);
}

/* Loading Overlay */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    transition: opacity var(--transition-smooth);
}

.loading-content {
    background: var(--surface-color);
    padding: 2.5rem;
    border-radius: var(--radius-large);
    text-align: center;
    max-width: 400px;
    box-shadow: var(--shadow-heavy);
}

.loading-spinner {
    margin-bottom: 1.5rem;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 3px solid var(--border-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto;
}

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

.loading-content h2 {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.loading-content p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.5;
}

.progress-bar {
    width: 100%;
    height: 6px;
    background: var(--background-color);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 0.75rem;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 3px;
    transition: width 0.3s ease;
    width: 0%;
}

.progress-text {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.error-content {
    padding: 1rem;
}

.error-content i {
    font-size: 3rem;
    color: #FF3B30;
    margin-bottom: 1rem;
}

.error-content h2 {
    color: #FF3B30;
}

.retry-button {
    margin-top: 1rem;
    padding: 0.75rem 1.5rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: var(--radius-medium);
    cursor: pointer;
    font-size: 1rem;
    transition: all var(--transition-fast);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.retry-button:hover {
    background: #0056CC;
}

/* Responsive Design */
@media (max-width: 768px) {
    .app-container {
        height: 100vh;
        max-width: 100%;
        box-shadow: none;
    }

    .header {
        padding: 1rem;
    }

    .header-content {
        flex-direction: column;
        gap: 0.75rem;
        text-align: center;
    }

    .model-status {
        display: none;
    }

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

    .chat-messages {
        padding: 1rem;
    }

    .input-container {
        padding: 0.75rem 1rem;
    }
}

/* Dark mode support */
@media (prefers-color-scheme: dark) {
    :root {
        --background-color: #000000;
        --surface-color: #1C1C1E;
        --text-primary: #FFFFFF;
        --text-secondary: #8E8E93;
        --border-color: #38383A;
    }

    .header {
        background: linear-gradient(135deg, #0056CC, #4444AA);
    }

    #messageInput {
        background: #2C2C2E;
        color: var(--text-primary);
    }

    #messageInput:focus {
        background: var(--surface-color);
    }

    .message-text {
        background: #2C2C2E;
    }

    .message.system .message-content {
        background: #2C2C2E;
    }
}