:root {
    --primary: #0EA5E9;
    --primary-dark: #0284C7;
    --primary-light: #E0F2FE;
    --bg: #F8FAFC;
    --surface: #FFFFFF;
    --text: #1E293B;
    --text-secondary: #64748B;
    --text-muted: #94A3B8;
    --border: #E2E8F0;
    --border-focus: #0EA5E9;
    --radius: 12px;
    --radius-sm: 8px;
    --shadow: 0 1px 3px rgba(0,0,0,0.08);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.1);

    --expert-surgery: #2563EB;
    --expert-ortho: #059669;
    --expert-rehab: #D97706;
    --expert-psych: #9333EA;

    --danger: #EF4444;
    --success: #22C55E;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
    min-height: 100vh;
}

/* Header */
.header {
    background: var(--surface);
    border-bottom: 1px solid var(--border);
    padding: 12px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 12px;
}

.header-logo {
    width: 36px;
    height: 36px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: bold;
    font-size: 14px;
}

.header-title {
    font-size: 18px;
    font-weight: 600;
    color: var(--text);
}

.header-code {
    background: var(--primary-light);
    color: var(--primary-dark);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    display: none;
}

.header-code.visible { display: inline-block; }

.header-right {
    display: flex;
    gap: 8px;
    align-items: center;
}

.btn {
    padding: 8px 16px;
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

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

.btn-primary:hover { background: var(--primary-dark); }

.btn-outline {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
}

.btn-sm {
    padding: 6px 12px;
    font-size: 13px;
}

/* Main layout */
.app-container {
    display: grid;
    grid-template-columns: 220px 1fr;
    height: calc(100vh - 57px);
    height: calc(100dvh - 57px);
}

.main-content {
    overflow-y: auto;
    display: flex;
    flex-direction: column;
}

/* Loading / Spinner */
.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    display: inline-block;
}

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

/* Toast */
.toast {
    position: fixed;
    top: 80px;
    right: 24px;
    background: var(--text);
    color: white;
    padding: 12px 20px;
    border-radius: var(--radius-sm);
    font-size: 14px;
    z-index: 1000;
    animation: slideIn 0.3s ease;
}

@keyframes slideIn {
    from { transform: translateX(100px); opacity: 0; }
    to { transform: translateX(0); opacity: 1; }
}

/* Modal */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 200;
}

.modal {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 32px;
    max-width: 480px;
    width: 90%;
    box-shadow: var(--shadow-lg);
}

.modal h2 {
    margin-bottom: 16px;
    font-size: 20px;
}

.modal input {
    width: 100%;
    padding: 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 16px;
    margin-bottom: 16px;
}

.modal input:focus {
    outline: none;
    border-color: var(--border-focus);
}

.hidden { display: none !important; }