/* Root Variables */
:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f7fa;
    --bg-tertiary: #e8ecf0;
    --text-primary: #1a1a1a;
    --text-secondary: #666666;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    --border: #e5e7eb;
    --shadow: rgba(0, 0, 0, 0.1);
    --shadow-lg: rgba(0, 0, 0, 0.15);
    --online: #10b981;
    --offline: #9ca3af;
}

/* Dark Mode Variables */
[data-theme="dark"] {
    --bg-primary: #1a1a1a;
    --bg-secondary: #242424;
    --bg-tertiary: #2d2d2d;
    --text-primary: #e5e5e5;
    --text-secondary: #a3a3a3;
    --border: #404040;
    --shadow: rgba(0, 0, 0, 0.3);
    --shadow-lg: rgba(0, 0, 0, 0.5);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
        'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    background-color: var(--bg-secondary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

/* Buttons */
.btn-primary, .btn-secondary, .btn-danger {
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    width: 100%;
}

.btn-primary {
    background: var(--accent);
    color: white;
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px var(--shadow-lg);
}

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

.btn-secondary:hover {
    background: var(--border);
}

.btn-danger {
    background: var(--danger);
    color: white;
}

.btn-danger:hover {
    background: #dc2626;
}

.icon-btn {
    background: transparent;
    border: none;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    transition: background 0.2s;
    position: relative;
}

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

.btn-send {
    padding: 10px 20px;
    background: var(--accent);
    color: white;
    border: none;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
}

.btn-send:hover {
    background: var(--accent-hover);
}

/* Avatar */
.avatar {
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--accent), #8b5cf6);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 18px;
    flex-shrink: 0;
}

.avatar.small {
    width: 35px;
    height: 35px;
    font-size: 14px;
}

.avatar.large {
    width: 60px;
    height: 60px;
    font-size: 24px;
}

/* Status Indicators */
.status {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    color: var(--text-secondary);
}

.status::before {
    content: '';
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: var(--offline);
}

.status.online::before {
    background: var(--online);
    box-shadow: 0 0 8px var(--online);
}

/* Badge */
.badge {
    position: absolute;
    top: -4px;
    right: -4px;
    background: var(--danger);
    color: white;
    font-size: 11px;
    font-weight: 700;
    padding: 2px 6px;
    border-radius: 10px;
    min-width: 18px;
    text-align: center;
}

/* Verified Badge */
.verified {
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.verified::after {
    content: '✓';
    background: var(--accent);
    color: white;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 10px;
    font-weight: bold;
}

/* Form Elements */
.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
    color: var(--text-primary);
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 15px;
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: all 0.2s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

/* Error Message */
.error-message {
    color: var(--danger);
    font-size: 14px;
    margin-top: 10px;
    display: none;
}

.error-message.show {
    display: block;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    justify-content: center;
    align-items: center;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: var(--bg-primary);
    border-radius: 16px;
    width: 90%;
    max-width: 500px;
    max-height: 80vh;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: 0 20px 60px var(--shadow-lg);
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px;
    border-bottom: 1px solid var(--border);
}

.modal-header h3 {
    font-size: 20px;
}

.modal-close {
    background: none;
    border: none;
    font-size: 28px;
    color: var(--text-secondary);
    cursor: pointer;
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: background 0.2s;
}

.modal-close:hover {
    background: var(--bg-tertiary);
}

.modal-body {
    padding: 20px;
    overflow-y: auto;
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--text-secondary);
}

.empty-state p {
    font-size: 16px;
    margin-bottom: 8px;
}

.empty-state small {
    font-size: 14px;
}

/* Loading Spinner */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid var(--border);
    border-top-color: var(--accent);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-secondary);
}

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

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* Responsive */
@media (max-width: 768px) {
    .avatar {
        width: 40px;
        height: 40px;
        font-size: 16px;
    }

    .btn-primary, .btn-secondary, .btn-danger {
        padding: 10px 20px;
        font-size: 14px;
    }
}

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

.fade-in {
    animation: fadeIn 0.3s ease;
}

@keyframes slideIn {
    from {
        transform: translateX(-100%);
    }
    to {
        transform: translateX(0);
    }
}

.slide-in {
    animation: slideIn 0.3s ease;
}