:root {
    --bg-primary: #f0f4f9;
    --bg-secondary: #ffffff;
    --bg-card: rgba(255, 255, 255, 0.72);
    --bg-input: rgba(255, 255, 255, 0.50);
    --text-primary: #0b1e33;
    --text-secondary: #2c4a6a;
    --text-muted: #6a8aa8;
    --border-color: rgba(255, 255, 255, 0.60);
    --shadow-color: rgba(0, 20, 40, 0.12);
    --shadow-strong: rgba(0, 20, 40, 0.20);
    --gradient-start: #0066ff;
    --gradient-end: #00b4ff;
    --bubble-ai: #ffffff;
    --bubble-user: linear-gradient(135deg, #0066ff, #0088ff);
    --bubble-user-text: #ffffff;
    --glass-blur: 16px;
    --transition-speed: 0.35s;
    --scrollbar-track: rgba(0, 0, 0, 0.03);
    --scrollbar-thumb: rgba(0, 100, 255, 0.20);
}

[data-theme="dark"] {
    --bg-primary: #0d1b2a;
    --bg-secondary: #1b2d45;
    --bg-card: rgba(27, 45, 69, 0.85);
    --bg-input: rgba(27, 45, 69, 0.70);
    --text-primary: #e8f0f8;
    --text-secondary: #b0cce0;
    --text-muted: #7a9ab8;
    --border-color: rgba(255, 255, 255, 0.10);
    --shadow-color: rgba(0, 0, 0, 0.40);
    --shadow-strong: rgba(0, 0, 0, 0.60);
    --bubble-ai: #1b2d45;
    --bubble-user: linear-gradient(135deg, #0055dd, #0077ee);
    --bubble-user-text: #ffffff;
    --glass-blur: 20px;
    --scrollbar-track: rgba(255, 255, 255, 0.05);
    --scrollbar-thumb: rgba(0, 100, 255, 0.30);
}

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

body {
    font-family: 'Vazirmatn', sans-serif;
    background: var(--bg-primary);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    transition: background var(--transition-speed) ease;
}

.assistant-card {
    max-width: 820px;
    width: 100%;
    background: var(--bg-card);
    backdrop-filter: blur(var(--glass-blur));
    -webkit-backdrop-filter: blur(var(--glass-blur));
    border-radius: 56px;
    padding: 32px 32px 24px;
    box-shadow: 0 25px 60px var(--shadow-strong), 0 8px 24px var(--shadow-color);
    border: 1px solid var(--border-color);
    transition: all var(--transition-speed) ease;
    position: relative;
    overflow: hidden;
}

.assistant-card::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle at 30% 20%, rgba(0, 102, 255, 0.04) 0%, transparent 60%);
    pointer-events: none;
    z-index: 0;
}

.assistant-card > * {
    position: relative;
    z-index: 1;
}

.header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 2px solid rgba(0, 102, 255, 0.08);
    flex-wrap: wrap;
    gap: 12px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 16px;
}

.avatar {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    border-radius: 22px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 34px;
    color: #fff;
    box-shadow: 0 10px 24px rgba(0, 102, 255, 0.30);
    flex-shrink: 0;
    transition: transform 0.3s ease;
}

.avatar:hover {
    transform: scale(1.05) rotate(-4deg);
}

.header-info h1 {
    font-size: 26px;
    font-weight: 900;
    color: var(--text-primary);
    letter-spacing: -0.5px;
    line-height: 1.2;
}

.header-info p {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 8px;
}

.status-dot {
    display: inline-block;
    width: 10px;
    height: 10px;
    background: #2ecc71;
    border-radius: 50%;
    animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
    0% { opacity: 0.5; transform: scale(0.9); }
    50% { opacity: 1; transform: scale(1.3); }
    100% { opacity: 0.5; transform: scale(0.9); }
}

.theme-toggle {
    background: var(--bg-input);
    border: 1px solid var(--border-color);
    border-radius: 40px;
    padding: 10px 18px;
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.3s ease;
    backdrop-filter: blur(4px);
    font-family: 'Vazirmatn', sans-serif;
    white-space: nowrap;
}

.theme-toggle:hover {
    background: rgba(0, 102, 255, 0.10);
    transform: scale(1.02);
}

.chat-box {
    background: var(--bg-input);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border-radius: 28px;
    padding: 18px 20px;
    height: 360px;
    overflow-y: auto;
    margin-bottom: 18px;
    border: 1px solid var(--border-color);
    box-shadow: inset 0 4px 12px rgba(0, 0, 0, 0.02);
    display: flex;
    flex-direction: column;
    gap: 14px;
    scroll-behavior: smooth;
    transition: all var(--transition-speed) ease;
}

.chat-box::-webkit-scrollbar {
    width: 5px;
}
.chat-box::-webkit-scrollbar-track {
    background: var(--scrollbar-track);
    border-radius: 10px;
}
.chat-box::-webkit-scrollbar-thumb {
    background: var(--scrollbar-thumb);
    border-radius: 10px;
}

.message {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    max-width: 88%;
    animation: fadeUp 0.35s ease;
}

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

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

.message .bubble {
    padding: 12px 20px;
    border-radius: 22px;
    font-size: 15px;
    line-height: 1.8;
    word-break: break-word;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.04);
    transition: all var(--transition-speed) ease;
}

.message.ai .bubble {
    background: var(--bubble-ai);
    color: var(--text-primary);
    border-bottom-right-radius: 6px;
    border: 1px solid var(--border-color);
}

.message.user .bubble {
    background: var(--bubble-user);
    color: var(--bubble-user-text);
    border-bottom-left-radius: 6px;
    border: none;
}

.message .icon {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
    flex-shrink: 0;
    background: var(--bg-input);
    backdrop-filter: blur(2px);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    transition: all var(--transition-speed) ease;
}

.message.user .icon {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: #fff;
    border: none;
}

.message.system .bubble {
    background: var(--bg-input) !important;
    border-right: 4px solid #f39c12;
    color: var(--text-primary);
}

.message.success .bubble {
    background: var(--bg-input) !important;
    border-right: 4px solid #2ecc71;
    color: var(--text-primary);
}

.message.warning .bubble {
    background: var(--bg-input) !important;
    border-right: 4px solid #e74c3c;
    color: var(--text-primary);
}

.welcome-msg .bubble {
    background: var(--bg-input) !important;
    backdrop-filter: blur(4px);
    border: 1px solid var(--border-color);
}

.input-area {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-input);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    border-radius: 60px;
    padding: 6px 6px 6px 20px;
    border: 1px solid var(--border-color);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.02);
    transition: all 0.3s ease;
}

.input-area:focus-within {
    border-color: var(--gradient-start);
    box-shadow: 0 4px 20px rgba(0, 100, 255, 0.12);
}

.input-area input {
    flex: 1;
    border: none;
    background: transparent;
    padding: 14px 4px;
    font-family: 'Vazirmatn', sans-serif;
    font-size: 15px;
    color: var(--text-primary);
    outline: none;
    transition: color var(--transition-speed) ease;
}

.input-area input::placeholder {
    color: var(--text-muted);
    font-weight: 400;
}

.input-area button {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    border: none;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    color: #fff;
    font-size: 22px;
    cursor: pointer;
    transition: all 0.25s ease;
    box-shadow: 0 6px 16px rgba(0, 100, 255, 0.25);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.input-area button:hover:not(:disabled) {
    transform: scale(1.06);
    box-shadow: 0 8px 24px rgba(0, 100, 255, 0.35);
}

.input-area button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.footer {
    text-align: center;
    margin-top: 18px;
    font-size: 13px;
    color: var(--text-muted);
    font-weight: 400;
    letter-spacing: 0.3px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    flex-wrap: wrap;
    transition: color var(--transition-speed) ease;
}

.footer-version {
    background: var(--bg-input);
    padding: 2px 12px;
    border-radius: 20px;
    font-size: 11px;
    font-weight: 700;
    color: var(--text-secondary);
    border: 1px solid var(--border-color);
}

@media (max-width: 700px) {
    .assistant-card { padding: 24px 18px 18px; border-radius: 40px; }
    .header { flex-direction: column; align-items: stretch; gap: 14px; }
    .header-left { gap: 12px; }
    .header-info h1 { font-size: 22px; }
    .theme-toggle { align-self: flex-start; padding: 8px 16px; font-size: 13px; }
    .chat-box { height: 280px; padding: 14px 16px; }
    .message { max-width: 95%; }
    .message .bubble { font-size: 14px; padding: 10px 16px; }
    .message .icon { width: 34px; height: 34px; font-size: 16px; }
    .input-area input { font-size: 14px; padding: 12px 2px; }
    .input-area button { width: 48px; height: 48px; font-size: 18px; }
}

@media (max-width: 450px) {
    body { padding: 12px; }
    .assistant-card { padding: 16px 12px 14px; border-radius: 32px; }
    .avatar { width: 50px; height: 50px; font-size: 26px; border-radius: 18px; }
    .header-info h1 { font-size: 19px; }
    .chat-box { height: 230px; padding: 12px 12px; border-radius: 20px; }
    .message .bubble { font-size: 13px; padding: 8px 14px; }
    .message .icon { width: 30px; height: 30px; font-size: 14px; }
    .input-area { padding: 4px 4px 4px 14px; border-radius: 40px; }
    .input-area input { font-size: 13px; padding: 10px 2px; }
    .input-area button { width: 42px; height: 42px; font-size: 16px; }
}