:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --light-bg: #f8fafc;
    --card-bg: #ffffff;
    --border-color: #e2e8f0;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --shadow: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1);
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--light-bg);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Login */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}
.login-container { width: 100%; max-width: 400px; padding: 20px; }
.login-box {
    background: var(--card-bg);
    border-radius: 12px;
    padding: 40px;
    box-shadow: var(--shadow-lg);
}
.login-header { text-align: center; margin-bottom: 30px; }
.login-header h1 { font-size: 1.75rem; color: var(--primary-color); margin-bottom: 8px; }
.login-header p { color: var(--text-secondary); font-size: 0.9rem; }
.login-footer { text-align: center; margin-top: 20px; color: var(--text-secondary); font-size: 0.85rem; }

/* Navbar */
.navbar {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    box-shadow: var(--shadow);
}
.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.nav-brand h2 { font-size: 1.35rem; color: var(--primary-color); }
.nav-version { font-size: 0.75em; color: var(--text-secondary); font-weight: 400; }
.nav-menu { display: flex; align-items: center; gap: 12px; }
.nav-user { color: var(--text-secondary); font-size: 0.9rem; }

.container { max-width: 1200px; margin: 0 auto; padding: 24px 20px; }

/* Tabs */
.tabs {
    display: flex;
    gap: 4px;
    border-bottom: 2px solid var(--border-color);
    margin-bottom: 24px;
    overflow-x: auto;
}
.tab-btn {
    display: inline-flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 10px 16px;
    background: none;
    border: none;
    border-bottom: 3px solid transparent;
    cursor: pointer;
    color: var(--text-secondary);
    font-weight: 500;
    font-size: 0.85rem;
    transition: all 0.2s;
}
.tab-btn__icon { font-size: 1.2rem; }
.tab-btn:hover { color: var(--primary-color); background: rgba(37,99,235,0.05); }
.tab-btn.active { color: var(--primary-color); border-bottom-color: var(--primary-color); }
.tab-content { display: none; }
.tab-content.active { display: block; }

/* Forms & buttons */
.form-group { margin-bottom: 16px; }
.form-group label { display: block; margin-bottom: 6px; font-weight: 500; }
.form-hint { display: block; margin-top: 4px; font-size: 0.8rem; color: var(--text-secondary); }
.form-control {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    font-size: 0.95rem;
}
.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}
.password-wrapper { position: relative; }
.password-wrapper input { padding-right: 44px; }
.password-toggle {
    position: absolute; right: 8px; top: 50%; transform: translateY(-50%);
    background: none; border: none; cursor: pointer; font-size: 1.1rem;
}
.code-editor { font-family: 'Consolas', 'Monaco', monospace; font-size: 0.85rem; }

.btn {
    display: inline-block;
    padding: 8px 16px;
    border-radius: 6px;
    border: 1px solid transparent;
    cursor: pointer;
    font-size: 0.9rem;
    font-weight: 500;
    text-decoration: none;
    transition: all 0.2s;
}
.btn-primary { background: var(--primary-color); color: #fff; }
.btn-primary:hover { filter: brightness(1.08); }
.btn-success { background: var(--success-color); color: #fff; }
.btn-danger { background: var(--danger-color); color: #fff; }
.btn-outline { background: transparent; border-color: var(--border-color); color: var(--text-primary); }
.btn-outline:hover { border-color: var(--primary-color); color: var(--primary-color); }
.btn-sm { padding: 6px 12px; font-size: 0.85rem; }
.btn-block { width: 100%; }

.alert { padding: 12px; border-radius: 6px; margin-bottom: 16px; }
.alert-error { background: #fef2f2; color: #991b1b; border: 1px solid #fecaca; }
.alert-info { background: #eff6ff; color: #1e40af; border: 1px solid #bfdbfe; }

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
    flex-wrap: wrap;
    gap: 12px;
}
.section-header h3 { font-size: 1.25rem; }
.section-header-actions { display: flex; gap: 8px; flex-wrap: wrap; align-items: center; }
.section-divider { margin: 32px 0; border: none; border-top: 1px solid var(--border-color); }

.config-status { margin-bottom: 12px; font-size: 0.9rem; }
.config-status.ok { color: var(--success-color); }
.config-status.err { color: var(--danger-color); }

.table-container { overflow-x: auto; margin-bottom: 24px; }
.data-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--card-bg);
    border-radius: 8px;
    overflow: hidden;
    box-shadow: var(--shadow);
}
.data-table th, .data-table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}
.data-table th { background: #f1f5f9; font-weight: 600; font-size: 0.85rem; }
.data-table tr:hover { background: #f8fafc; }
.text-center { text-align: center; }
.text-muted { color: var(--text-secondary); font-size: 0.9rem; margin-bottom: 12px; }
.env-matrix-desc { max-width: 720px; }

.table-container--env-matrix { max-height: 70vh; overflow: auto; }
.data-table--env-matrix { font-size: 0.82rem; white-space: nowrap; }
.data-table--env-matrix th,
.data-table--env-matrix td {
    max-width: 220px;
    overflow: hidden;
    text-overflow: ellipsis;
}
.data-table--env-matrix .col-host-id {
    position: sticky;
    left: 0;
    z-index: 2;
    background: #f1f5f9;
    font-weight: 600;
    min-width: 72px;
    box-shadow: 2px 0 4px rgba(0,0,0,0.06);
}
.data-table--env-matrix tbody .col-host-id { background: var(--card-bg); }
.data-table--env-matrix tr:hover .col-host-id { background: #f8fafc; }
.data-table--env-matrix thead .col-host-id { z-index: 3; }

.oid-panel {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 8px;
    padding: 16px 20px;
    margin-bottom: 16px;
}
.oid-panel-row {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 16px 24px;
}
.oid-panel-row > div { font-size: 0.9rem; }
.oid-value {
    display: inline-block;
    margin-left: 8px;
    font-family: Consolas, Monaco, monospace;
    color: var(--primary-color);
    font-weight: 600;
}
.oid-hostname {
    display: inline-block;
    margin-left: 8px;
    font-size: 0.85rem;
    background: #f1f5f9;
    padding: 4px 8px;
    border-radius: 4px;
}
.oid-hint { margin-top: 12px; margin-bottom: 0; font-size: 0.85rem; }

.editor-panel {
    background: var(--card-bg);
    padding: 20px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    margin-bottom: 24px;
}

.prop-content-group { margin-top: 8px; }
.prop-editor-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 4px;
}
.prop-editor-header label { margin: 0; font-weight: 600; }
.prop-editor-modes { display: flex; gap: 6px; }
.prop-mode-btn.active {
    background: var(--primary-color, #0ea5e9);
    color: #fff;
    border-color: var(--primary-color, #0ea5e9);
}
.prop-editor-hint { margin-bottom: 12px; }
.prop-kv-container { margin-bottom: 10px; max-height: 420px; overflow: auto; }
.prop-kv-table input.form-control {
    font-size: 0.875rem;
    padding: 6px 10px;
}
.prop-kv-actions-col { width: 44px; text-align: center; }
.prop-kv-remove {
    min-width: 32px;
    padding: 4px 8px;
    line-height: 1;
}
.prop-raw-view textarea { min-height: 320px; }

/* Headscale tab */
.headscale-tab { max-width: 1100px; margin: 0 auto; }
.headscale-hero {
    background: linear-gradient(145deg, #0c2540 0%, #132f4f 50%, #0f2942 100%);
    color: #fff;
    padding: 28px 32px;
    border-radius: 12px;
    margin-bottom: 24px;
    box-shadow: 0 12px 40px rgba(15,41,66,0.28);
}
.headscale-hero-top {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 16px;
    margin-bottom: 14px;
}
.headscale-hero-badge {
    font-size: 0.68rem;
    letter-spacing: 0.12em;
    text-transform: uppercase;
    color: rgba(255,255,255,0.55);
    font-weight: 600;
}
.headscale-hero-actions { display: flex; align-items: center; gap: 12px; margin-left: auto; }
.headscale-pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    border-radius: 999px;
    font-size: 0.875rem;
    font-weight: 600;
    background: rgba(0,0,0,0.28);
    border: 1px solid rgba(255,255,255,0.12);
}
.headscale-pill-dot { width: 8px; height: 8px; border-radius: 50%; background: #64748b; }
.headscale-pill-ok .headscale-pill-dot { background: #22c55e; box-shadow: 0 0 0 3px rgba(34,197,94,0.35); }
.headscale-pill-muted .headscale-pill-dot { background: #94a3b8; }
.headscale-btn-primary {
    background: #0ea5e9 !important;
    color: #fff !important;
    border: none !important;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
}
.headscale-hero-title { font-size: 1.75rem; font-weight: 700; margin: 0 0 12px; }
.headscale-hero-desc { opacity: 0.85; max-width: 640px; }
.headscale-cards { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
@media (max-width: 768px) { .headscale-cards { grid-template-columns: 1fr; } }
.headscale-card {
    background: var(--card-bg);
    border-radius: 10px;
    padding: 20px;
    box-shadow: var(--shadow);
    border: 1px solid var(--border-color);
}
.headscale-card--full { grid-column: 1 / -1; }
.headscale-card-title { font-size: 1rem; margin-bottom: 14px; color: var(--text-primary); }
.headscale-dl { display: grid; grid-template-columns: auto 1fr; gap: 8px 16px; font-size: 0.9rem; }
.headscale-dl dt { color: var(--text-secondary); font-weight: 500; }
.headscale-dl dd { margin: 0; word-break: break-all; }
.headscale-actions-btns { display: flex; gap: 10px; flex-wrap: wrap; margin-bottom: 12px; }
.headscale-btn-outline {
    background: transparent !important;
    border: 1px solid var(--border-color) !important;
    color: var(--text-primary) !important;
}
.headscale-status-pre {
    background: #0f172a;
    color: #e2e8f0;
    padding: 16px;
    border-radius: 8px;
    font-size: 0.8rem;
    overflow-x: auto;
    max-height: 320px;
    white-space: pre-wrap;
}
.headscale-inline-status { font-size: 0.9rem; margin-top: 8px; }