:root {
    --bg: #f4f6fb;
    --surface: #ffffff;
    --text: #1d2433;
    --muted: #677084;
    --border: #dfe5f1;
    --primary: #1ea0f2;
    --primary-2: #16c2a3;
    --danger: #e74c3c;
    --shadow: 0 10px 30px rgba(17, 35, 62, 0.08);
}

[data-theme="dark"] {
    --bg: #091426;
    --surface: #0f1f38;
    --text: #e5edf9;
    --muted: #96a5c0;
    --border: #22314d;
    --primary: #23a8f3;
    --primary-2: #20cfad;
    --danger: #ff6f6f;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
}

* { box-sizing: border-box; }
html, body { margin: 0; padding: 0; font-family: "Segoe UI", Tahoma, Arial, sans-serif; background: var(--bg); color: var(--text); }
a { color: inherit; text-decoration: none; }
.topbar { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 12px 20px; background: var(--surface); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 20; }
.brand { display: flex; align-items: baseline; gap: 10px; }
.brand-mark { font-weight: 800; font-size: 20px; color: var(--primary); }
.brand-sub { color: var(--muted); font-size: 14px; }
.topbar-actions { display: flex; align-items: center; gap: 10px; }
.container { width: 100%; padding: 20px; }
.app-shell { display: grid; grid-template-columns: 240px 1fr; align-items: start; min-height: calc(100vh - 62px); }
.sidebar { position: sticky; top: 62px; height: calc(100vh - 62px); background: var(--surface); border-right: 1px solid var(--border); padding: 14px 10px; }
.nav-list { display: grid; gap: 6px; }
.nav-item { display: block; border: 1px solid transparent; border-radius: 8px; padding: 10px 12px; color: var(--muted); font-size: 14px; }
.nav-item:hover { border-color: var(--border); color: var(--text); }
.nav-item.active { background: linear-gradient(90deg, rgba(30, 160, 242, 0.16), rgba(22, 194, 163, 0.12)); color: var(--text); border-color: rgba(30, 160, 242, 0.4); }
.page-head h1 { margin: 0 0 8px; }
.page-head p { margin: 0; color: var(--muted); }
.stats-grid, .module-grid { display: grid; gap: 14px; margin-top: 16px; }
.stats-grid { grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); }
.module-grid { grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.stat-card, .module-card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; padding: 14px; box-shadow: var(--shadow); }
a.module-card { display: block; }
.stat-card h3, .module-card h3 { margin: 0 0 8px; font-size: 15px; }
.stat-card p, .module-card p { margin: 0; color: var(--muted); }
.panel-card { background: var(--surface); border: 1px solid var(--border); border-radius: 12px; box-shadow: var(--shadow); padding: 14px; }
.panel-card h2 { margin: 0 0 12px; font-size: 17px; }
.panel-card + .panel-card { margin-top: 14px; }
.table-wrap { width: 100%; overflow: auto; }
table { width: 100%; border-collapse: collapse; }
th, td { border-bottom: 1px solid var(--border); padding: 9px 10px; text-align: left; font-size: 13px; }
th { color: var(--muted); font-weight: 600; }
.grid-2, .grid-3, .grid-4 { display: grid; gap: 10px; }
.grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.grid-4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.actions { display: flex; flex-wrap: wrap; gap: 8px; align-items: end; }
.alert-success { background: rgba(22, 194, 163, 0.18); border: 1px solid rgba(22, 194, 163, 0.55); color: #d8fff5; }
.alert-info { background: rgba(30, 160, 242, 0.12); border: 1px solid rgba(30, 160, 242, 0.45); color: #c4e7ff; }
.login-page { min-height: 100vh; display: grid; grid-template-columns: 1fr 1fr; }
.login-hero { background: linear-gradient(130deg, rgba(6, 12, 25, 0.48), rgba(6, 12, 25, 0.7)), url("https://images.unsplash.com/photo-1503387762-592deb58ef4e?auto=format&fit=crop&w=1600&q=80") center/cover no-repeat; display: flex; align-items: end; padding: 36px; }
.hero-overlay h1 { margin: 0; font-size: 42px; letter-spacing: 2px; }
.hero-overlay p { margin: 4px 0 0; color: #d9e5ff; }
.login-panel { display: grid; place-items: center; background: radial-gradient(circle at 5% 5%, #18345f, #091426 65%); padding: 20px; }
.login-card { width: min(460px, 94%); background: rgba(10, 22, 44, 0.9); color: #eff4ff; border: 1px solid #213657; border-radius: 14px; padding: 24px; box-shadow: var(--shadow); }
.login-card h2 { margin: 0 0 8px; }
.login-card p { margin: 0 0 18px; color: #adc0df; }
.form-grid { display: grid; gap: 14px; }
label span { display: block; margin-bottom: 6px; font-size: 13px; }
input, select, textarea { width: 100%; background: #fff; border: 1px solid #c9d2e4; border-radius: 7px; padding: 10px 12px; font-size: 14px; }
input:focus, select:focus, textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(35, 168, 243, 0.18); }
.btn { border: 0; border-radius: 8px; padding: 9px 13px; font-weight: 600; cursor: pointer; font-size: 14px; display: inline-flex; align-items: center; justify-content: center; gap: 8px; }
.btn-primary { background: linear-gradient(90deg, var(--primary), var(--primary-2)); color: #fff; }
.btn-outline { border: 1px solid var(--border); background: transparent; }
.btn-ghost { border: 1px solid var(--border); background: var(--surface); color: var(--text); }
.theme-toggle { min-width: 42px; min-height: 38px; padding: 6px 10px; font-size: 18px; line-height: 1; }

.backup-option {
    display: block;
    width: 100%;
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 14px;
    margin: 8px 0;
    background: var(--surface);
    color: var(--text);
    text-align: left;
    font-weight: 600;
}

.backup-option.primary {
    border-color: rgba(30, 160, 242, 0.7);
    background: linear-gradient(90deg, rgba(30, 160, 242, 0.16), rgba(22, 194, 163, 0.2));
}

.backup-note {
    background: rgba(255, 206, 84, 0.12);
    border: 1px solid rgba(255, 206, 84, 0.5);
    border-radius: 8px;
    padding: 10px 12px;
}

.icon-actions {
    display: flex;
    gap: 8px;
    align-items: center;
}

.icon-btn {
    border: 1px solid var(--border);
    background: var(--surface);
    color: var(--text);
    border-radius: 8px;
    width: 34px;
    height: 34px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 15px;
}

.icon-btn:hover {
    border-color: rgba(30, 160, 242, 0.65);
}

.icon-btn.delete {
    border-color: rgba(231, 76, 60, 0.45);
    color: #cc5e53;
}

.modal-backdrop {
    position: fixed;
    inset: 0;
    background: rgba(4, 11, 24, 0.6);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 999;
    padding: 14px;
}

.modal-backdrop.show {
    display: flex;
}

.modal-card {
    width: min(760px, 100%);
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 12px;
    box-shadow: var(--shadow);
    padding: 16px;
}

.modal-head {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}
.alert { border-radius: 8px; padding: 10px 12px; margin-bottom: 12px; font-size: 14px; transition: opacity .35s ease, transform .35s ease; opacity: 1; }
.alert-error { background: rgba(231, 76, 60, 0.15); border: 1px solid rgba(231, 76, 60, 0.45); color: #ffd2cc; }
.alert.fade-out { opacity: 0; transform: translateY(-4px); }
.user-chip { display: flex; flex-direction: column; line-height: 1.1; }
.user-chip small { color: var(--muted); }
@media (max-width: 900px) {
    .app-shell { grid-template-columns: 1fr; }
    .sidebar { position: static; height: auto; border-right: 0; border-bottom: 1px solid var(--border); }
    .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
    .login-page { grid-template-columns: 1fr; }
    .login-hero { min-height: 180px; align-items: center; }
    .hero-overlay h1 { font-size: 30px; }
}