:root {
    --bg-color: #0f172a;
    --chat-bg: #1e293b;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --user-msg: #3b82f6;
    --ai-msg: #334155;
    --border: #334155;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
}

.chat-container {
    width: 100%;
    max-width: 900px;
    height: 90vh;
    background-color: var(--chat-bg);
    border-radius: 16px;
    display: flex;
    flex-direction: column;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    border: 1px solid var(--border);
    overflow: hidden;
}

.chat-header {
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
    background: rgba(30, 41, 59, 0.8);
    backdrop-filter: blur(10px);
}

.chat-header h1 {
    font-size: 1.25rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-main);
}

.chat-header p {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-top: 6px;
}

.chat-messages {
    flex: 1;
    padding: 24px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 20px;
}

/* Custom Scrollbar */
.chat-messages::-webkit-scrollbar {
    width: 8px;
}
.chat-messages::-webkit-scrollbar-track {
    background: transparent;
}
.chat-messages::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}
.chat-messages::-webkit-scrollbar-thumb:hover {
    background: #475569;
}

.message {
    display: flex;
    max-width: 80%;
    animation: fadeIn 0.3s ease;
}

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

.user-message {
    align-self: flex-end;
}

.ai-message {
    align-self: flex-start;
}

.message-content {
    padding: 14px 18px;
    border-radius: 18px;
    font-size: 0.95rem;
    line-height: 1.5;
    word-wrap: break-word;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* Formatage des éléments Markdown générés par marked.js */
.message-content p {
    margin-bottom: 8px;
}
.message-content p:last-child {
    margin-bottom: 0;
}
.message-content h1, .message-content h2, .message-content h3 {
    margin-top: 12px;
    margin-bottom: 8px;
    font-weight: 600;
}
.message-content ul, .message-content ol {
    margin-left: 20px;
    margin-bottom: 8px;
}
.message-content li {
    margin-bottom: 4px;
}
.message-content strong {
    font-weight: 600;
}

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

.ai-message .message-content {
    background-color: var(--ai-msg);
    border-bottom-left-radius: 4px;
}

.chat-input-container {
    padding: 20px 24px;
    border-top: 1px solid var(--border);
    background-color: var(--chat-bg);
}

#chat-form {
    display: flex;
    gap: 12px;
}

#chat-input {
    flex: 1;
    background-color: #0f172a;
    border: 1px solid var(--border);
    color: var(--text-main);
    padding: 16px 24px;
    border-radius: 30px;
    font-size: 1rem;
    outline: none;
    transition: all 0.2s;
}

#chat-input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

#send-btn {
    background-color: var(--primary);
    color: white;
    border: none;
    width: 54px;
    height: 54px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all 0.2s;
}

#send-btn:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

#send-btn:active {
    transform: translateY(0);
}

.file-upload-btn {
    background-color: var(--chat-bg);
    color: var(--text-muted);
    border: 1px solid var(--border);
    width: 54px;
    height: 54px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all 0.2s;
}

.file-upload-btn:hover {
    color: var(--primary);
    border-color: var(--primary);
    transform: translateY(-2px);
}

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

.typing-indicator {
    display: flex;
    gap: 5px;
    padding: 16px 20px;
    background-color: var(--ai-msg);
    border-radius: 18px;
    border-bottom-left-radius: 4px;
    align-self: flex-start;
    width: fit-content;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

.typing-dot {
    width: 8px;
    height: 8px;
    background-color: var(--text-muted);
    border-radius: 50%;
    animation: typing 1.4s infinite ease-in-out both;
}

.typing-dot:nth-child(1) { animation-delay: -0.32s; }
.typing-dot:nth-child(2) { animation-delay: -0.16s; }

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

/* --- Login Form Styles --- */
.login-container {
    width: 100%;
    max-width: 420px;
    padding: 20px;
}

.login-box {
    background-color: var(--chat-bg);
    border: 1px solid var(--border);
    border-radius: 20px;
    padding: 40px 32px;
    text-align: center;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    animation: fadeIn 0.4s ease;
}

.login-icon {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 24px;
    animation: fadeIn 0.6s ease;
}

.login-box h2 {
    color: var(--text-main);
    margin-bottom: 12px;
    font-weight: 600;
    font-size: 1.5rem;
}

.login-box p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 28px;
    line-height: 1.5;
}

.error-msg {
    background-color: rgba(239, 68, 68, 0.1);
    color: #ef4444;
    padding: 12px;
    border-radius: 8px;
    font-size: 0.9rem;
    margin-bottom: 24px;
    border: 1px solid rgba(239, 68, 68, 0.2);
    animation: fadeIn 0.3s ease;
}

.login-box form {
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.login-box input {
    background-color: #0f172a;
    border: 1px solid var(--border);
    color: var(--text-main);
    padding: 16px 20px;
    border-radius: 10px;
    font-size: 1rem;
    outline: none;
    transition: all 0.2s;
    text-align: center;
}

.login-box input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.login-box button {
    background-color: var(--primary);
    color: white;
    border: none;
    padding: 16px;
    border-radius: 10px;
    font-size: 1.05rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.login-box button:hover {
    background-color: var(--primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.login-box button:active {
    transform: translateY(0);
}

.logout-btn {
    position: absolute;
    top: 50%;
    right: 24px;
    transform: translateY(-50%);
    background: transparent;
    color: var(--text-muted);
    border: 1px solid var(--border);
    padding: 8px 16px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 0.85rem;
    transition: all 0.2s;
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logout-btn:hover {
    color: white;
    border-color: var(--text-muted);
    background: rgba(255, 255, 255, 0.05);
}