:root,
[data-bs-theme="light"] {
    --pf-bg: #f0f2f5;
    --pf-sidebar: #1a2332;
    --pf-sidebar-text: #c5cdd8;
    --pf-accent: #2f6fed;
    --pf-accent-hover: #2458c4;
    --pf-border: #d8dee6;
    --pf-card: #ffffff;
    --pf-muted: #6b7280;
    --pf-text: #1f2937;
    --pf-step-bg: #f8fafc;
    --pf-icon-bg: #eef1f5;
    --pf-auth-bg:
        radial-gradient(ellipse at top left, rgba(47,111,237,.18), transparent 50%),
        linear-gradient(160deg, #e8edf5 0%, #f5f7fb 45%, #dfe6f1 100%);
    --pf-loading-card: #ffffff;
    --pf-loading-text: #374151;
    --pf-loading-overlay: rgba(26, 35, 50, .45);
    --pf-stat-danger: #b42318;
    --pf-stat-ok: #027a48;
}

[data-bs-theme="dark"] {
    --pf-bg: #0f1419;
    --pf-sidebar: #0b1017;
    --pf-sidebar-text: #a8b3c4;
    --pf-accent: #5b8fff;
    --pf-accent-hover: #7aa3ff;
    --pf-border: #2a3444;
    --pf-card: #171e28;
    --pf-muted: #9aa4b2;
    --pf-text: #e8edf5;
    --pf-step-bg: #121820;
    --pf-icon-bg: #1f2835;
    --pf-auth-bg:
        radial-gradient(ellipse at top left, rgba(91,143,255,.16), transparent 50%),
        linear-gradient(160deg, #0b1017 0%, #121820 45%, #0f1419 100%);
    --pf-loading-card: #171e28;
    --pf-loading-text: #d1d9e6;
    --pf-loading-overlay: rgba(0, 0, 0, .55);
    --pf-stat-danger: #f97066;
    --pf-stat-ok: #32d583;
    color-scheme: dark;
}

* { box-sizing: border-box; }

body.app-body {
    margin: 0;
    min-height: 100vh;
    background: var(--pf-bg);
    font-family: "Segoe UI", system-ui, sans-serif;
    color: var(--pf-text);
}

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

.sidebar {
    width: 240px;
    background: linear-gradient(180deg, #1a2332 0%, #121925 100%);
    color: var(--pf-sidebar-text);
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    padding: 1.25rem 0;
}

.sidebar .brand {
    padding: 0 1.25rem 1.5rem;
    border-bottom: 1px solid rgba(255,255,255,.08);
    margin-bottom: 1rem;
}

.sidebar .brand h1 {
    margin: 0;
    font-size: 1.05rem;
    color: #fff;
    font-weight: 650;
    letter-spacing: .01em;
}

.sidebar .brand small {
    color: #8b97a8;
    font-size: .75rem;
}

.sidebar nav a {
    display: block;
    padding: .65rem 1.25rem;
    color: var(--pf-sidebar-text);
    text-decoration: none;
    font-size: .92rem;
    border-left: 3px solid transparent;
}

.sidebar nav a:hover,
.sidebar nav a.active {
    background: rgba(255,255,255,.05);
    color: #fff;
    border-left-color: var(--pf-accent);
}

.sidebar .sidebar-footer {
    margin-top: auto;
    padding: 1rem 1.25rem;
    border-top: 1px solid rgba(255,255,255,.08);
    font-size: .8rem;
}

.main-panel {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.topbar {
    background: var(--pf-card);
    border-bottom: 1px solid var(--pf-border);
    padding: .85rem 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.content {
    padding: 1.5rem;
}

.stat-card {
    background: var(--pf-card);
    border: 1px solid var(--pf-border);
    border-radius: .5rem;
    padding: 1.1rem 1.25rem;
    height: 100%;
}

.stat-card .stat-value {
    font-size: 1.75rem;
    font-weight: 700;
    line-height: 1.1;
}

.stat-card .stat-label {
    color: var(--pf-muted);
    font-size: .85rem;
    margin-top: .25rem;
}

.stat-card.danger .stat-value { color: var(--pf-stat-danger); }
.stat-card.ok .stat-value { color: var(--pf-stat-ok); }

.topbar-actions {
    display: flex;
    align-items: center;
    gap: .75rem;
}

.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.25rem;
    height: 2.25rem;
    padding: 0;
    border-radius: .45rem;
    border: 1px solid var(--pf-border);
    background: var(--pf-card);
    color: var(--pf-text);
    cursor: pointer;
    transition: background .15s ease, border-color .15s ease, color .15s ease;
}

.theme-toggle:hover {
    border-color: var(--pf-accent);
    color: var(--pf-accent);
}

.theme-toggle-floating {
    position: fixed;
    top: 1rem;
    right: 1rem;
    z-index: 10;
    box-shadow: 0 4px 16px rgba(0, 0, 0, .12);
}

[data-bs-theme="light"] .theme-toggle-icon-sun,
[data-bs-theme="dark"] .theme-toggle-icon-moon {
    display: none;
}

[data-bs-theme="dark"] .theme-toggle-icon-sun,
[data-bs-theme="light"] .theme-toggle-icon-moon {
    display: inline-flex;
}

.panel {
    background: var(--pf-card);
    border: 1px solid var(--pf-border);
    border-radius: .5rem;
    padding: 1.25rem;
    margin-bottom: 1.25rem;
}

.software-icon {
    width: 36px;
    height: 36px;
    object-fit: contain;
    border-radius: .25rem;
    background: var(--pf-icon-bg);
}

.software-icon.placeholder {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: .7rem;
    color: var(--pf-muted);
}

.step-list {
    list-style: none;
    margin: 0;
    padding: 0;
}

.step-item {
    background: var(--pf-step-bg);
    border: 1px solid var(--pf-border);
    border-radius: .5rem;
    padding: .85rem 1rem;
    margin-bottom: .65rem;
    cursor: grab;
}

.step-item.dragging {
    opacity: .55;
}

.step-item .step-type {
    font-weight: 600;
    font-size: .9rem;
}

.step-item .step-preview {
    color: var(--pf-muted);
    font-size: .82rem;
    font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    margin-top: .2rem;
    word-break: break-all;
}

.step-item.disabled-step {
    opacity: .55;
}

.badge-arch, .badge-installer {
    font-weight: 500;
}

.auth-wrap {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--pf-auth-bg);
    color: var(--pf-text);
}

.auth-card {
    width: 100%;
    max-width: 420px;
    background: var(--pf-card);
    border: 1px solid var(--pf-border);
    border-radius: .65rem;
    padding: 2rem;
    box-shadow: 0 12px 40px rgba(26, 35, 50, .08);
    color: var(--pf-text);
}

[data-bs-theme="dark"] .auth-card {
    box-shadow: 0 12px 40px rgba(0, 0, 0, .35);
}

.auth-card h1 {
    font-size: 1.35rem;
    margin-bottom: .35rem;
}

.nav-tabs .nav-link { color: var(--pf-muted); }
.nav-tabs .nav-link.active { font-weight: 600; color: var(--pf-text); }

[data-bs-theme="dark"] .table {
    --bs-table-bg: transparent;
    --bs-table-color: var(--pf-text);
    --bs-table-border-color: var(--pf-border);
    --bs-table-striped-bg: rgba(255, 255, 255, .03);
    --bs-table-hover-bg: rgba(255, 255, 255, .05);
}

[data-bs-theme="dark"] .form-control,
[data-bs-theme="dark"] .form-select {
    background-color: #121820;
    border-color: var(--pf-border);
    color: var(--pf-text);
}

[data-bs-theme="dark"] .form-control:focus,
[data-bs-theme="dark"] .form-select:focus {
    background-color: #121820;
    border-color: var(--pf-accent);
    color: var(--pf-text);
}

[data-bs-theme="dark"] .modal-content {
    background-color: var(--pf-card);
    border-color: var(--pf-border);
    color: var(--pf-text);
}

[data-bs-theme="dark"] .list-group-item {
    background-color: var(--pf-card);
    border-color: var(--pf-border);
    color: var(--pf-text);
}

@media (max-width: 768px) {
    .app-shell { flex-direction: column; }
    .sidebar { width: 100%; }
}

/* Full-page loading overlay */
.app-loading {
    position: fixed;
    inset: 0;
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--pf-loading-overlay);
    backdrop-filter: blur(2px);
}

.app-loading[hidden] {
    display: none !important;
}

.app-loading-card {
    background: var(--pf-loading-card);
    border: 1px solid var(--pf-border);
    border-radius: .65rem;
    padding: 1.5rem 1.75rem;
    min-width: 260px;
    max-width: min(90vw, 420px);
    text-align: center;
    box-shadow: 0 16px 48px rgba(26, 35, 50, .2);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: .85rem;
}

.app-loading-text {
    color: var(--pf-loading-text);
    font-size: .95rem;
    line-height: 1.4;
}

body.app-loading-active {
    overflow: hidden;
}

.btn .spinner-border-sm {
    width: .9rem;
    height: .9rem;
    border-width: .15em;
}

/* App footer + changelog reader */
.app-footer {
    margin-top: auto;
    border-top: 1px solid var(--pf-border);
    background: var(--pf-card);
    padding: .65rem 1.5rem;
}

.app-footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    font-size: .85rem;
}

.app-footer-brand {
    color: var(--pf-muted);
}

.app-footer-version {
    display: inline-flex;
    align-items: center;
    gap: .5rem;
    border: 1px solid var(--pf-border);
    background: var(--pf-bg);
    color: var(--pf-text);
    border-radius: 999px;
    padding: .25rem .7rem;
    font-size: .8rem;
    font-weight: 600;
    cursor: pointer;
    transition: border-color .15s ease, color .15s ease;
}

.app-footer-version:hover {
    border-color: var(--pf-accent);
    color: var(--pf-accent);
}

.app-footer-version-hint {
    font-weight: 500;
    color: var(--pf-muted);
}

.changelog-modal .modal-body {
    min-height: min(70vh, 640px);
}

.changelog-layout {
    display: grid;
    grid-template-columns: 220px 1fr;
    min-height: min(70vh, 640px);
}

.changelog-nav {
    border-right: 1px solid var(--pf-border);
    background: var(--pf-step-bg);
    overflow: auto;
}

.changelog-nav-item {
    display: block;
    width: 100%;
    text-align: left;
    border: 0;
    border-bottom: 1px solid var(--pf-border);
    background: transparent;
    color: var(--pf-text);
    padding: .85rem 1rem;
    cursor: pointer;
}

.changelog-nav-item:hover {
    background: rgba(47, 111, 237, .08);
}

.changelog-nav-item.active {
    background: rgba(47, 111, 237, .14);
    box-shadow: inset 3px 0 0 var(--pf-accent);
}

.changelog-nav-item .ver {
    display: block;
    font-weight: 650;
    font-size: .92rem;
}

.changelog-nav-item .date {
    display: block;
    color: var(--pf-muted);
    font-size: .75rem;
    margin-top: .15rem;
}

.changelog-reader {
    padding: 1.25rem 1.5rem;
    overflow: auto;
}

.changelog-md h1,
.changelog-md h2,
.changelog-md h3 {
    margin-top: 1.1rem;
    margin-bottom: .55rem;
    font-weight: 650;
}

.changelog-md h2:first-child {
    margin-top: 0;
}

.changelog-md ul {
    padding-left: 1.2rem;
}

.changelog-md li {
    margin-bottom: .35rem;
}

.changelog-md code {
    font-size: .85em;
    background: var(--pf-icon-bg);
    padding: .1rem .35rem;
    border-radius: .25rem;
}

.changelog-md blockquote {
    margin: .75rem 0;
    padding: .5rem .85rem;
    border-left: 3px solid var(--pf-accent);
    background: var(--pf-step-bg);
    color: var(--pf-muted);
}

@media (max-width: 768px) {
    .changelog-layout {
        grid-template-columns: 1fr;
    }

    .changelog-nav {
        border-right: 0;
        border-bottom: 1px solid var(--pf-border);
        max-height: 180px;
    }
}