:root {
    --bg-primary: #f3f4f6;
    --sidebar-bg: #1f2937;
    --sidebar-text: #ffffff;
    --accent-color: #2563eb;
    --accent-hover: #1d4ed8;
    --text-dark: #1f2937;
    --border-color: #e5e7eb;
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif; }
body { background-color: var(--bg-primary); color: var(--text-dark); height: 100vh; overflow: hidden; }

/* Utilidades */
.hidden { display: none !important; }

/* Estilos de Login */
.login-container { display: flex; justify-content: center; align-items: center; height: 100vh; background: linear-gradient(135deg, #1f2937 0%, #111827 100%); }
.login-box { background: white; padding: 2.5rem; border-radius: 12px; width: 100%; max-width: 400px; box-shadow: 0 10px 25px rgba(0,0,0,0.3); }
.login-box h2 { margin-bottom: 0.5rem; color: #111827; font-size: 1.8rem; text-align: center; }
.login-subtitle { color: #6b7280; font-size: 0.9rem; margin-bottom: 2rem; text-align: center; }
.form-group { margin-bottom: 1.25rem; }
.form-group label { display: block; margin-bottom: 0.5rem; font-size: 0.85rem; font-weight: 600; color: #374151; }
.form-group input { width: 100%; padding: 0.75rem; border: 1px solid var(--border-color); border-radius: 6px; font-size: 1rem; outline: none; transition: border 0.2s; }
.form-group input:focus { border-color: var(--accent-color); }
.error-text { color: #ef4444; font-size: 0.85rem; margin-bottom: 1rem; text-align: center; }
.btn-login { width: 100%; padding: 0.75rem; background-color: var(--accent-color); color: white; border: none; border-radius: 6px; font-size: 1rem; font-weight: 600; cursor: pointer; transition: background 0.2s; }
.btn-login:hover { background-color: var(--accent-hover); }

/* Estilos Dashboard */
.dashboard-wrapper { display: flex; height: 100vh; width: 100vw; }
.sidebar { width: 260px; background-color: var(--sidebar-bg); color: var(--sidebar-text); display: flex; flex-direction: column; transition: width 0.3s; z-index: 10; }
.sidebar.collapsed { width: 70px; }
.sidebar-header { padding: 1.5rem; display: flex; justify-content: space-between; align-items: center; border-bottom: 1px solid #374151; }
.logo-text { font-weight: bold; font-size: 1.2rem; tracking: 1px; }
.sidebar.collapsed .logo-text { display: none; }
.toggle-btn { background: none; border: none; color: white; cursor: pointer; font-size: 1rem; padding: 0.25rem; }
.sidebar-nav { flex: 1; padding: 1rem 0; }
.sidebar-nav ul { list-style: none; }
.nav-item { padding: 0.75rem 1.5rem; display: flex; align-items: center; cursor: pointer; transition: background 0.2s; }
.nav-item:hover, .nav-item.active { background-color: #374151; border-left: 4px solid var(--accent-color); }
.nav-item a { color: var(--sidebar-text); text-decoration: none; display: flex; align-items: center; width: 100%; }
.nav-icon { margin-right: 1rem; font-size: 1.2rem; }
.sidebar.collapsed .nav-text { display: none; }
.sidebar.collapsed .nav-item { padding: 0.75rem; justify-content: center; }
.sidebar.collapsed .nav-icon { margin-right: 0; }
.sidebar-footer { padding: 1.5rem; border-top: 1px solid #374151; background-color: #111827; }
.user-badge { font-size: 0.85rem; margin-bottom: 0.75rem; color: #9ca3af; text-overflow: ellipsis; overflow: hidden; white-space: nowrap; }
.sidebar.collapsed .sidebar-footer { display: none; }
.btn-logout { width: 100%; padding: 0.5rem; background-color: #374151; color: white; border: none; border-radius: 4px; cursor: pointer; font-size: 0.85rem; }
.btn-logout:hover { background-color: #ef4444; }

/* Contenido Principal */
.main-content { flex: 1; background-color: var(--bg-primary); display: flex; flex-direction: column; height: 100vh; overflow-y: auto; }
.content-container { padding: 2rem; max-width: 1200px; width: 100%; margin: 0 auto; }
.module-card { background: white; padding: 2rem; border-radius: 8px; box-shadow: 0 4px 6px rgba(0,0,0,0.05); border: 1px solid var(--border-color); }
.module-card h2 { margin-bottom: 1rem; color: #111827; }