:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #eff6ff;
    --color-bg: #f4f6f9;
    --color-surface: #ffffff;
    --color-border: #e2e8f0;
    --color-text: #0f172a;
    --color-text-muted: #64748b;
    --color-success-bg: #dcfce7;
    --color-success-text: #166534;
    --color-warning-bg: #fef3c7;
    --color-warning-text: #92400e;
    --color-error-bg: #fee2e2;
    --color-error-text: #991b1b;
    --radius: 8px;
    --sidebar-width: 250px;
    --topbar-height: 60px;
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
}

body {
    font-family: system-ui, -apple-system, "Segoe UI", sans-serif;
    color: var(--color-text);
    background: var(--color-bg);
    font-size: 14px;
    line-height: 1.5;
}

/* ---- Halaman otentikasi (login, install, error tanpa sesi) ---- */

body.auth {
    background: var(--color-bg);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px 16px;
}

.auth-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(15, 23, 42, 0.06), 0 8px 24px rgba(15, 23, 42, 0.04);
    padding: 32px;
    max-width: 420px;
    width: 100%;
}

.auth-brand {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-primary);
    margin: 0 0 20px;
    text-align: center;
}

/* ---- Kerangka aplikasi (setelah login) ---- */

body.app {
    display: flex;
    min-height: 100vh;
}

.app-sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    background: var(--color-surface);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    overflow-y: auto;
    transition: transform 0.2s ease;
    z-index: 20;
}

.app-brand {
    display: block;
    font-size: 18px;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
    padding: 18px 20px;
    border-bottom: 1px solid var(--color-border);
}

.app-nav {
    padding: 12px;
    flex: 1;
}

.app-nav-group {
    font-size: 11px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-text-muted);
    padding: 16px 12px 6px;
}

.app-nav-group:first-child {
    padding-top: 4px;
}

.nav-link {
    display: block;
    padding: 9px 12px;
    border-radius: 6px;
    color: var(--color-text);
    text-decoration: none;
    font-size: 14px;
    margin-bottom: 2px;
}

.nav-link:hover {
    background: var(--color-bg);
}

.nav-link.active {
    background: var(--color-primary);
    color: #fff;
    font-weight: 600;
}

.app-content-wrap {
    margin-left: var(--sidebar-width);
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.app-topbar {
    height: var(--topbar-height);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 24px;
    position: sticky;
    top: 0;
    z-index: 10;
}

.app-topbar-user {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 13px;
    color: var(--color-text-muted);
}

.app-topbar-user strong {
    color: var(--color-text);
}

.app-topbar form {
    display: inline;
}

.app-topbar button {
    background: transparent;
    color: var(--color-text-muted);
    border: 1px solid var(--color-border);
    padding: 6px 12px;
    font-size: 13px;
}

.app-topbar button:hover {
    background: var(--color-bg);
    color: var(--color-text);
}

.nav-toggle {
    display: none;
    background: transparent;
    border: 1px solid var(--color-border);
    color: var(--color-text);
    padding: 6px 10px;
    border-radius: 6px;
    cursor: pointer;
}

.app-main {
    flex: 1;
    padding: 28px 32px;
    max-width: 1240px;
    width: 100%;
}

.app-content-wrap.full-width {
    margin-left: 0;
}

.card.info-card {
    margin-bottom: 20px;
}

.info-card-title {
    font-size: 18px;
    font-weight: 700;
    margin: 2px 0 4px;
}

.w-network-diagram {
    max-width: 520px;
}

.network-svg {
    width: 100%;
    height: auto;
    display: block;
}

.app-brand.plain {
    padding: 0;
    border: none;
}

@media (max-width: 860px) {
    .app-sidebar {
        transform: translateX(-100%);
    }
    body.app.nav-open .app-sidebar {
        transform: translateX(0);
        box-shadow: 4px 0 16px rgba(15, 23, 42, 0.15);
    }
    .app-content-wrap {
        margin-left: 0;
    }
    .nav-toggle {
        display: inline-block;
    }
    .app-main {
        padding: 20px 16px;
    }
}

/* ---- Tipografi & elemen umum ---- */

h1 {
    font-size: 22px;
    font-weight: 700;
    margin: 0 0 18px;
    color: var(--color-text);
}

h2 {
    font-size: 16px;
    font-weight: 600;
    margin: 28px 0 12px;
    color: var(--color-text);
}

h2:first-child {
    margin-top: 0;
}

p {
    margin: 0 0 12px;
}

a {
    color: var(--color-primary);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* ---- Form ---- */

form {
    display: flex;
    flex-direction: column;
    gap: 12px;
    max-width: 480px;
}

form.inline,
.inline-form {
    flex-direction: row;
    align-items: flex-end;
    flex-wrap: wrap;
    max-width: none;
}

label {
    font-size: 13px;
    font-weight: 600;
    color: var(--color-text);
}

input[type="text"],
input[type="password"],
input[type="email"],
input[type="number"],
input[type="date"],
select,
textarea {
    padding: 9px 11px;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    font-size: 14px;
    font-family: inherit;
    background: var(--color-surface);
    color: var(--color-text);
}

input:focus,
select:focus,
textarea:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 1px;
    border-color: var(--color-primary);
}

button,
input[type="submit"] {
    padding: 9px 16px;
    border: none;
    border-radius: 6px;
    background: var(--color-primary);
    color: #fff;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    align-self: flex-start;
}

button:hover,
input[type="submit"]:hover {
    background: var(--color-primary-dark);
}

button:disabled {
    background: var(--color-text-muted);
    cursor: not-allowed;
}

/* ---- Tabel ---- */

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    overflow: hidden;
    margin: 12px 0 16px;
}

th, td {
    padding: 10px 14px;
    text-align: left;
    border-bottom: 1px solid var(--color-border);
    font-size: 13.5px;
}

thead th {
    font-size: 11.5px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--color-text-muted);
    background: var(--color-bg);
}

tbody tr:last-child td {
    border-bottom: none;
}

tbody tr:hover {
    background: var(--color-bg);
}

/* ---- Kartu / panel ---- */

.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 20px;
    margin-bottom: 16px;
}

/* ---- Pesan status & badge ---- */

.error {
    background: var(--color-error-bg);
    color: var(--color-error-text);
    padding: 10px 14px;
    border-radius: 6px;
    font-size: 14px;
    margin-bottom: 12px;
}

.success {
    background: var(--color-success-bg);
    color: var(--color-success-text);
    padding: 10px 14px;
    border-radius: 6px;
    font-size: 14px;
    margin-bottom: 12px;
}

.warning {
    background: var(--color-warning-bg);
    color: var(--color-warning-text);
    padding: 10px 14px;
    border-radius: 6px;
    font-size: 14px;
    margin-bottom: 12px;
}

.muted {
    font-size: 13px;
    color: var(--color-text-muted);
}

.badge {
    display: inline-block;
    padding: 2px 9px;
    border-radius: 999px;
    font-size: 12px;
    font-weight: 600;
}

.badge.success { background: var(--color-success-bg); color: var(--color-success-text); }
.badge.warning { background: var(--color-warning-bg); color: var(--color-warning-text); }
.badge.error { background: var(--color-error-bg); color: var(--color-error-text); }
.badge.muted { background: var(--color-bg); color: var(--color-text-muted); }

/* ---- Kartu (dengan bayangan halus) ---- */

.card {
    box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
}

/* ---- Pengumuman sistem ---- */

.app-announcement {
    margin: 16px 32px 0;
    border-radius: 6px;
}

/* ---- Grid statistik dashboard ---- */

.stat-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 16px;
    margin-bottom: 28px;
}

.stat-card {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.stat-label {
    font-size: 12.5px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.04em;
    color: var(--color-text-muted);
    margin: 0;
}

.stat-value {
    font-size: 28px;
    font-weight: 700;
    margin: 0;
    color: var(--color-text);
    line-height: 1.2;
}

.stat-value-sub {
    font-size: 14px;
    font-weight: 400;
    color: var(--color-text-muted);
}

/* ---- Panel bagian (mis. builder instrumen) ---- */

.section-card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 20px 24px;
    margin-bottom: 20px;
    box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
}

.section-card > h2:first-child,
.section-card > h3:first-child {
    margin-top: 0;
}

.section-card-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    flex-wrap: wrap;
}

/* ---- Daftar entitas (pengganti <ul> polos untuk bagian/dimensi/butir) ---- */

.entity-list {
    list-style: none;
    margin: 0 0 16px;
    padding: 0;
}

.entity-list > li {
    padding: 9px 0;
    border-bottom: 1px solid var(--color-border);
    font-size: 13.5px;
}

.entity-list > li:last-child {
    border-bottom: none;
}

.entity-block {
    padding: 16px 0;
    border-top: 1px solid var(--color-border);
}

.entity-block:first-of-type {
    border-top: none;
    padding-top: 0;
}

.entity-title {
    font-size: 14.5px;
}

.sublist {
    list-style: none;
    margin: 8px 0 12px;
    padding: 0;
}

.sublist > li {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    padding: 6px 0;
    font-size: 13.5px;
    border-bottom: 1px dashed var(--color-border);
}

.sublist > li:last-child {
    border-bottom: none;
}

/* ---- Baris aksi (tombol/form berdampingan, mis. di sel tabel) ---- */

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

.actions-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 20px;
}

.mt-md {
    margin-top: 14px;
}

.actions form {
    margin: 0;
}

.inline-action {
    display: inline-block;
}

/* ---- Utilitas lebar field ---- */

.w-xs { width: 80px; }
.w-sm { width: 100px; }
.w-md { width: 120px; }
.w-lg { width: 140px; }
.w-xl { width: 160px; }

.inline-form textarea {
    width: 220px;
    min-height: 38px;
}

/* ---- Kartu ringkas (mis. daftar tugas siswa) ---- */

.item-block {
    margin-bottom: 16px;
}

.option-label {
    display: block;
    font-weight: 400;
    padding: 2px 0;
}

/* ---- Heatmap frekuensi ---- */

.heat-cell {
    text-align: center;
    font-weight: 600;
}

.text-center {
    text-align: center;
}

/* ---- Halaman publik (homepage, paket) ---- */

body.public {
    background: var(--color-surface);
}

.public-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 18px 32px;
    border-bottom: 1px solid var(--color-border);
    max-width: 1100px;
    margin: 0 auto;
}

.public-brand {
    font-size: 20px;
    font-weight: 700;
    color: var(--color-primary);
    text-decoration: none;
}

.public-nav {
    display: flex;
    align-items: center;
    gap: 20px;
}

.public-nav a {
    color: var(--color-text);
    font-size: 14.5px;
    font-weight: 500;
}

.public-main {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 32px 60px;
}

.public-footer {
    border-top: 1px solid var(--color-border);
    padding: 24px 32px;
    text-align: center;
    color: var(--color-text-muted);
    font-size: 13px;
}

.newsletter-box {
    max-width: 480px;
    margin: 0 auto 20px;
    text-align: center;
}

.newsletter-heading {
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text);
    margin: 0 0 12px;
}

.newsletter-form {
    justify-content: center;
}

.btn {
    display: inline-block;
    padding: 11px 22px;
    border-radius: 6px;
    font-size: 14.5px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    border: 1px solid transparent;
}

.btn:hover {
    text-decoration: none;
}

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

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

.btn-outline {
    background: var(--color-surface);
    color: var(--color-primary);
    border-color: var(--color-primary);
}

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

.hero {
    text-align: center;
    padding: 72px 0 56px;
}

.hero h1 {
    font-size: 36px;
    margin: 0 0 16px;
}

.hero p {
    font-size: 17px;
    color: var(--color-text-muted);
    max-width: 640px;
    margin: 0 auto 28px;
}

.hero-actions {
    display: flex;
    gap: 12px;
    justify-content: center;
    flex-wrap: wrap;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin: 40px 0;
}

.feature-card h3 {
    margin: 0 0 8px;
    font-size: 16px;
}

.feature-card p {
    margin: 0;
    font-size: 13.5px;
    color: var(--color-text-muted);
}

.section-heading {
    text-align: center;
    margin-bottom: 32px;
}

.section-heading h2 {
    font-size: 26px;
    margin: 0 0 8px;
}

.section-heading p {
    color: var(--color-text-muted);
    margin: 0;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    align-items: stretch;
}

.pricing-card {
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.pricing-card.featured {
    border-color: var(--color-primary);
    box-shadow: 0 2px 4px rgba(37, 99, 235, 0.08), 0 8px 20px rgba(37, 99, 235, 0.08);
}

.pricing-card-name {
    font-size: 18px;
    font-weight: 700;
    margin: 0;
}

.pricing-card-price {
    font-size: 26px;
    font-weight: 700;
    margin: 0;
}

.pricing-card-price-period {
    font-size: 13px;
    font-weight: 400;
    color: var(--color-text-muted);
}

.pricing-card-features {
    list-style: none;
    margin: 0;
    padding: 0;
    flex: 1;
}

.pricing-card-features li {
    padding: 6px 0;
    font-size: 13.5px;
    border-bottom: 1px dashed var(--color-border);
}

.pricing-card-features li:last-child {
    border-bottom: none;
}

.heat-0 { background-color: rgba(220, 38, 38, 0); }
.heat-1 { background-color: rgba(220, 38, 38, 0.18); }
.heat-2 { background-color: rgba(220, 38, 38, 0.36); }
.heat-3 { background-color: rgba(220, 38, 38, 0.54); color: #fff; }
.heat-4 { background-color: rgba(220, 38, 38, 0.75); color: #fff; }
.heat-5 { background-color: rgba(220, 38, 38, 0.92); color: #fff; }