/* App-Stylesheet — Learnikus
 * Komponenten-CSS auf Basis von tokens.css. Keine Hex-Werte hier;
 * alles uebers Token-Set. Layout: mobile-first, ab md: Top-Bar +
 * Side-Nav; xs/sm: Bottom-Tab-Bar.
 */

*, *::before, *::after { box-sizing: border-box; }

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

html {
    font-family: var(--font-sans);
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    text-rendering: optimizeLegibility;
}

body {
    min-height: 100dvh;
    background: var(--color-bg);
    color: var(--color-text);
    font-size: var(--text-body);
    line-height: var(--leading-base);
}

img, svg { display: block; max-width: 100%; }

a {
    color: var(--color-brand);
    text-decoration: none;
}
a:hover { color: var(--color-brand-hover); text-decoration: underline; }

:focus-visible {
    outline: 2px solid var(--color-brand);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

/* Visually-hidden (a11y) */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* Skip-Link (a11y) */
.skip-link {
    position: absolute;
    left: var(--space-2);
    top: var(--space-2);
    padding: var(--space-2) var(--space-3);
    background: var(--color-surface);
    color: var(--color-text);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    transform: translateY(-150%);
    transition: transform var(--motion-fast) var(--motion-easing);
    z-index: var(--z-topbar);
}
.skip-link:focus { transform: translateY(0); }

/* ----- Layout-Grid ----- */
.app-shell {
    display: grid;
    min-height: 100dvh;
    grid-template-rows: var(--layout-topbar-h-mob) 1fr var(--layout-bottombar-h);
    grid-template-columns: 1fr;
    grid-template-areas:
        "topbar"
        "main"
        "bottombar";
}

@media (min-width: 768px) {
    .app-shell {
        grid-template-rows: var(--layout-topbar-h) 1fr;
        grid-template-columns: var(--layout-sidenav-w) 1fr;
        grid-template-areas:
            "topbar  topbar"
            "sidenav main";
    }
}

.app-topbar {
    grid-area: topbar;
    position: sticky;
    top: 0;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 0 var(--space-4);
    z-index: var(--z-topbar);
}

.app-topbar__brand {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    font-weight: var(--weight-bold);
    color: var(--color-text);
}
.app-topbar__brand img,
.app-topbar__brand svg { height: 28px; width: auto; }

.app-topbar__title {
    flex: 1;
    text-align: center;
    font-size: var(--text-body);
    font-weight: var(--weight-semibold);
    color: var(--color-text-muted);
}
@media (min-width: 768px) { .app-topbar__title { display: none; } }

.app-topbar__actions {
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

/* ----- Side-Nav (md+) ----- */
.app-sidenav {
    grid-area: sidenav;
    display: none;
    background: var(--color-surface);
    border-right: 1px solid var(--color-border);
    padding: var(--space-4) 0;
    z-index: var(--z-sidenav);
}
@media (min-width: 768px) { .app-sidenav { display: block; } }

.app-sidenav__list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
}
.app-sidenav__item a {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    color: var(--color-text-muted);
    border-left: 4px solid transparent;
    text-decoration: none;
    min-height: 44px;
}
.app-sidenav__item a:hover {
    color: var(--color-text);
    background: var(--color-brand-subtle);
}
.app-sidenav__item a.is-active {
    color: var(--color-text);
    border-left-color: var(--color-brand);
    background: var(--color-brand-subtle);
    font-weight: var(--weight-semibold);
}

/* ----- Main ----- */
.app-main {
    grid-area: main;
    padding: var(--space-4);
    overflow-x: hidden;
}
@media (min-width: 768px) {
    .app-main { padding: var(--space-6) var(--space-8); }
}

.app-container {
    max-width: var(--layout-content-max);
    margin: 0 auto;
    width: 100%;
}

/* ----- Bottom-Tab-Bar (xs/sm) ----- */
.app-bottombar {
    grid-area: bottombar;
    position: sticky;
    bottom: 0;
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    display: flex;
    align-items: stretch;
    z-index: var(--z-bottombar);
}
@media (min-width: 768px) { .app-bottombar { display: none; } }

.app-bottombar a {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2px;
    color: var(--color-text-muted);
    text-decoration: none;
    font-size: var(--text-caption);
    min-height: var(--layout-bottombar-h);
    border-top: 3px solid transparent;
}
.app-bottombar a.is-active {
    color: var(--color-brand);
    border-top-color: var(--color-brand);
}

/* ----- Card ----- */
.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-1);
    padding: var(--space-4);
}
@media (min-width: 768px) { .card { padding: var(--space-6); } }

.card__title {
    margin: 0 0 var(--space-3);
    font-size: var(--text-h3);
    font-weight: var(--weight-semibold);
    line-height: var(--leading-snug);
}
.card__lead {
    margin: 0 0 var(--space-4);
    color: var(--color-text-muted);
}

/* ----- Buttons ----- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    min-height: 44px;
    padding: 12px 20px;
    border-radius: var(--radius);
    border: 1px solid transparent;
    font: inherit;
    font-weight: var(--weight-semibold);
    cursor: pointer;
    text-decoration: none;
    transition: background-color var(--motion-fast) var(--motion-easing),
                color var(--motion-fast) var(--motion-easing),
                border-color var(--motion-fast) var(--motion-easing);
}
@media (min-width: 768px) { .btn { min-height: 40px; } }

.btn[disabled], .btn.is-disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.btn--primary {
    background: var(--color-brand);
    color: var(--color-brand-on);
}
.btn--primary:hover { background: var(--color-brand-hover); color: var(--color-brand-on); text-decoration: none; }

.btn--secondary {
    background: transparent;
    color: var(--color-brand);
    border-color: var(--color-brand);
}
.btn--secondary:hover { background: var(--color-brand-subtle); text-decoration: none; }

.btn--ghost {
    background: transparent;
    color: var(--color-text);
}
.btn--ghost:hover { background: var(--color-brand-subtle); text-decoration: none; }

.btn--destructive {
    background: var(--color-error);
    color: #FFFFFF;
}

/* ----- Form-Inputs ----- */
.input,
input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="search"],
select,
textarea {
    display: block;
    width: 100%;
    min-height: 44px;
    padding: 10px 14px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    color: var(--color-text);
    font: inherit;
}
.input:focus,
input:focus,
select:focus,
textarea:focus {
    outline: 2px solid var(--color-brand);
    outline-offset: 1px;
    border-color: var(--color-brand);
}

label { font-weight: var(--weight-semibold); display: block; margin-bottom: var(--space-2); }
.required { color: var(--color-error); margin-left: 2px; }
.helper { font-size: var(--text-body-sm); color: var(--color-text-subtle); margin-top: var(--space-1); }
.error  { font-size: var(--text-body-sm); color: var(--color-error);       margin-top: var(--space-1); }

/* ----- Status-Badges ----- */
.badge {
    display: inline-flex;
    align-items: center;
    gap: var(--space-1);
    padding: 2px 8px;
    border-radius: 999px;
    font-size: var(--text-caption);
    font-weight: var(--weight-semibold);
    border: 1px solid var(--color-border);
}
.badge--success { color: var(--color-success); border-color: currentColor; }
.badge--error   { color: var(--color-error);   border-color: currentColor; }
.badge--warning { color: var(--color-warning); border-color: currentColor; }
.badge--info    { color: var(--color-info);    border-color: currentColor; }

/* ----- HTMX-Indicator ----- */
.htmx-indicator { opacity: 0; transition: opacity var(--motion-fast) var(--motion-easing); }
.htmx-request   .htmx-indicator,
.htmx-request.htmx-indicator { opacity: 1; }

/* ----- Reduced Motion ----- */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}