:root {
    --bg: #f3f7fb;
    --panel: #ffffff;
    --panel-alt: #f8fbff;
    --sidebar: #0f172a;
    --sidebar-soft: #1e293b;
    --primary: #2563eb;
    --primary-soft: #dbeafe;
    --success: #16a34a;
    --success-soft: #dcfce7;
    --danger: #dc2626;
    --danger-soft: #fee2e2;
    --warning: #d97706;
    --warning-soft: #fef3c7;
    --text: #0f172a;
    --muted: #475569;
    --line: #e2e8f0;
    --shadow: 0 14px 32px rgba(15, 23, 42, 0.08);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; font-family: Arial, Helvetica, sans-serif; background: var(--bg); color: var(--text); }
a { text-decoration: none; }

.app-shell { display: flex; min-height: 100vh; }
.sidebar {
    width: 260px; background: linear-gradient(180deg, var(--sidebar) 0%, var(--sidebar-soft) 100%);
    color: white; padding: 24px 18px; position: sticky; top: 0; height: 100vh;
}
.brand {
    font-size: 1.3rem; font-weight: 700; letter-spacing: .04em; margin: 6px 0 24px; display: flex; align-items: center; gap: 10px;
}
.brand-mark {
    width: 34px; height: 34px; border-radius: 10px; display: grid; place-items: center; background: rgba(255,255,255,.12); font-size: 1.1rem;
}
.nav { display: flex; flex-direction: column; gap: 8px; }
.nav a {
    color: #dbeafe; padding: 12px 14px; border-radius: 12px; font-weight: 600; transition: .2s ease; display: block;
}
.nav a:hover { background: rgba(255,255,255,.06); }
.nav a.active {
    background: var(--primary); box-shadow: inset 0 0 0 1px rgba(255,255,255,.08);
}
.main {
    flex: 1; padding: 28px 32px 50px;
}
.topbar {
    background: rgba(255,255,255,0.72); border: 1px solid rgba(148,163,184,0.18); backdrop-filter: blur(10px);
    border-radius: 18px; padding: 18px 22px; box-shadow: var(--shadow); margin-bottom: 24px;
}
.topbar h1 { margin: 0; font-size: clamp(1.5rem, 2vw, 2.2rem); }
.panel {
    background: var(--panel); border: 1px solid var(--line); border-radius: 20px; box-shadow: var(--shadow); padding: 20px;
}
.stats-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 18px; margin-bottom: 24px;
}
.stat-card {
    background: linear-gradient(180deg, var(--panel) 0%, var(--panel-alt) 100%); border: 1px solid var(--line); border-radius: 18px; padding: 20px; box-shadow: var(--shadow);
}
.stat-card .label { font-size: .82rem; color: var(--muted); text-transform: uppercase; letter-spacing: .06em; }
.stat-card .value { font-size: clamp(1.7rem, 2vw, 2.3rem); font-weight: 700; margin-top: 8px; }
.alert {
    padding: 14px 16px; border-radius: 12px; font-weight: 600; margin-bottom: 22px; border: 1px solid transparent;
}
.alert.success { background: var(--success-soft); color: #166534; border-color: #bbf7d0; }
.alert.error { background: var(--danger-soft); color: #991b1b; border-color: #fecaca; }
.alert.warning { background: var(--warning-soft); color: #92400e; border-color: #fcd34d; }
.info-box {
    background: var(--primary-soft); border: 1px solid #bfdbfe; color: #1d4ed8; padding: 14px 16px; border-radius: 12px; margin-top: 18px;
}
.section-title { font-size: 1.15rem; font-weight: 700; margin: 0 0 18px; }
.form-card { background: var(--panel); border: 1px solid var(--line); border-radius: 20px; padding: 20px; box-shadow: var(--shadow); }
.form-grid {
    display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px;
}
.field { display: flex; flex-direction: column; gap: 8px; }
.field label { font-size: .9rem; color: var(--muted); font-weight: 700; }
.field input, .field select, .field textarea {
    width: 100%; border: 1px solid var(--line); background: #fff; border-radius: 12px; padding: 12px 14px; font-size: 1rem; color: var(--text); transition: .2s ease; outline: none;
}
.field input:focus, .field select:focus, .field textarea:focus {
    border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,.12);
}
.form-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 18px; }
.btn {
    border: none; border-radius: 12px; padding: 12px 18px; font-size: 1rem; font-weight: 700; cursor: pointer; transition: .2s ease; 
}
.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { filter: brightness(1.02); }
.btn-secondary { background: #e2e8f0; color: var(--text); }
.btn-success { background: var(--success); color: white; }
.btn-danger { background: var(--danger); color: white; }
.table-wrap { overflow: auto; }
table {
    width: 100%; border-collapse: collapse; background: white; border-radius: 18px; overflow: hidden; border: 1px solid var(--line);
}
th, td { padding: 14px 12px; border-bottom: 1px solid var(--line); text-align: left; }
th { background: #f8fafc; font-size: .85rem; text-transform: uppercase; letter-spacing: .06em; color: var(--muted); }
.pill {
    display: inline-flex; align-items: center; padding: 7px 10px; border-radius: 999px; background: var(--primary-soft); color: var(--primary); font-weight: 700; font-size: .82rem;
}
.link-btn { display: inline-flex; align-items: center; justify-content: center; padding: 9px 12px; background: var(--primary-soft); color: var(--primary); border-radius: 10px; font-weight: 700; }
.link-btn.danger { background: var(--danger-soft); color: var(--danger); }
.muted { color: var(--muted); }
@media (max-width: 860px) {
    .app-shell { display: block; }
    .sidebar { position: relative; width: 100%; height: auto; }
    .main { padding: 18px; }
}