:root {
    --bg-color: #f8fafc;
    --text-color: #1e293b;
    --text-muted: #64748b;
    --card-bg: #ffffff;
    --primary: #3b82f6;
    --primary-hover: #2563eb;
    --border-color: #e2e8f0;
    --sidebar-bg: #1e293b;
    --sidebar-text: #f8fafc;
    --sidebar-hover: #334155;
    --danger: #ef4444;
    --success: #10b981;
}

/* Dark mode support - automatické zjištění ze systému */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-color: #0f172a;
        --text-color: #f8fafc;
        --card-bg: #1e293b;
        --border-color: #334155;
    }
}

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

body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.5;
    display: flex;
    min-height: 100vh;
}

/* Formuláře */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background: var(--card-bg);
    color: var(--text-color);
    font-size: 1rem;
    transition: border-color 0.2s;
}

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

/* Tlačítka */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    text-align: center;
    text-decoration: none;
    transition: background-color 0.2s, transform 0.1s;
}

.btn:active {
    transform: scale(0.98);
}

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

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

.w-100 {
    width: 100%;
}

/* Rozložení: Sidebar + Obsah */
.app-container {
    display: flex;
    width: 100%;
}

/* Sidebar Navigation */
.sidebar {
    width: 260px;
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    display: flex;
    flex-direction: column;
    padding: 1.5rem 0;
    position: fixed;
    height: 100vh;
    overflow-y: auto;
}

.sidebar-header {
    padding: 0 1.5rem 1.5rem;
    border-bottom: 1px solid var(--sidebar-hover);
    margin-bottom: 1rem;
}

.sidebar-header h2 {
    font-size: 1.25rem;
    font-weight: 700;
    margin: 0;
}

.sidebar-nav {
    flex-grow: 1;
}

.sidebar-nav ul {
    list-style: none;
    padding: 0;
}

.sidebar-nav a {
    display: block;
    padding: 0.75rem 1.5rem;
    color: var(--sidebar-text);
    text-decoration: none;
    transition: background 0.2s;
    font-weight: 500;
}

.sidebar-nav a:hover,
.sidebar-nav a.active {
    background-color: var(--sidebar-hover);
    border-left: 4px solid var(--primary);
    padding-left: calc(1.5rem - 4px);
}

.sidebar-footer {
    padding: 1.5rem;
    border-top: 1px solid var(--sidebar-hover);
    font-size: 0.875rem;
}

.sidebar-footer a {
    color: #94a3b8;
    text-decoration: none;
}

.sidebar-footer a:hover {
    color: var(--danger);
}

/* Main Content Area */
.main-content {
    flex-grow: 1;
    margin-left: 260px;
    /* Šířka sidebaru */
    padding: 2rem;
}

/* Top bar (Header v obsahu) */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2rem;
    padding-bottom: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.page-header h1 {
    font-size: 1.875rem;
    font-weight: 700;
}

/* Karty a kontejner pro data */
.card {
    background: var(--card-bg);
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

/* Tabulky */
.table-responsive {
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
}

table th,
table td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

table th {
    font-weight: 600;
    color: var(--text-muted);
    font-size: 0.875rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

table tbody tr:hover {
    background-color: rgba(0, 0, 0, 0.02);
}

@media (prefers-color-scheme: dark) {
    table tbody tr:hover {
        background-color: rgba(255, 255, 255, 0.02);
    }
}

/* Responzivita (Mobilní layout) */
@media (max-width: 768px) {
    .app-container {
        flex-direction: column;
    }

    .sidebar {
        width: 100%;
        height: auto;
        position: static;
        padding: 1rem;
    }

    .sidebar-header {
        border-bottom: none;
        margin-bottom: 0;
        padding-bottom: 0;
    }

    .main-content {
        margin-left: 0;
        padding: 1rem;
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 1rem;
    }
}