:root {
    --color-bg: #f6f6f3;
    --color-surface: #ffffff;
    --color-text: #23262b;
    --color-muted: #666b72;
    --color-border: #dfe1de;
    --color-primary: #1c3a5e;
    --color-primary-dark: #14293f;
    --color-success: #2f6b45;
    --color-success-dark: #21502f;
    --color-success-bg: #eaf3ec;
    --color-success-border: #bcdac6;
    --color-danger: #9c342b;
    --color-danger-bg: #f8ebea;
    --color-danger-border: #e3bcb8;

    --admin-bg: #f1f1ee;
    --admin-surface: #ffffff;
    --admin-surface-alt: #eceeec;
    --admin-border: #dcdfdc;
    --admin-text: #23262b;
    --admin-accent-1: #1c3a5e;
    --admin-accent-2: #a9863f;
    --admin-gradient: var(--admin-accent-1);
    --admin-glow: 0 1px 2px rgba(20, 24, 28, 0.06), 0 2px 6px rgba(20, 24, 28, 0.06);

    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-pill: 4px;

    --shadow-sm: 0 1px 2px rgba(20, 24, 28, 0.06);
    --shadow-md: 0 2px 8px rgba(20, 24, 28, 0.08);

    --space-1: 4px;
    --space-2: 8px;
    --space-3: 12px;
    --space-4: 16px;
    --space-5: 24px;
    --space-6: 32px;
}

* {
    box-sizing: border-box;
}

.visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

body {
    margin: 0;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.5;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--color-primary);
}

/* ---------------------------------------------------------
   Layout
--------------------------------------------------------- */

.calendar-container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: var(--space-5) var(--space-4) var(--space-6);
}

h1 {
    font-size: clamp(1.4rem, 1.1rem + 1.2vw, 1.9rem);
    margin: 0 0 var(--space-2);
    letter-spacing: -0.01em;
    text-align: center;
    color: var(--color-primary);
    font-weight: 700;
}

.subtitle {
    color: var(--color-muted);
    margin: 0 0 var(--space-2);
    text-align: center;
}

/* ---------------------------------------------------------
   Flash messages
--------------------------------------------------------- */

.flash {
    border-radius: var(--radius-sm);
    padding: var(--space-3) var(--space-4);
    margin: var(--space-3) 0;
    font-size: 0.95rem;
    font-weight: 500;
}

.flash-success {
    background: var(--color-success-bg);
    border: 1px solid var(--color-success-border);
    color: var(--color-success-dark);
}

.flash-error {
    background: var(--color-danger-bg);
    border: 1px solid var(--color-danger-border);
    color: var(--color-danger);
}

/* ---------------------------------------------------------
   Calendar grid
--------------------------------------------------------- */

.calendar-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: var(--space-4);
    margin-top: var(--space-4);
}

.calendar-day {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    padding: var(--space-4);
    display: flex;
    flex-direction: column;
}

.day-header {
    border-bottom: 2px solid var(--color-primary);
    padding-bottom: var(--space-2);
    margin-bottom: var(--space-2);
    display: flex;
    align-items: baseline;
    gap: var(--space-2);
}

.day-weekday {
    font-size: 0.8rem;
    color: var(--color-muted);
    text-transform: uppercase;
    letter-spacing: 0.04em;
}

.day-date {
    font-weight: 700;
    color: var(--color-text);
}

.day-slots {
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
    margin-top: var(--space-2);
}

.empty-state {
    background: var(--color-surface);
    border: 1px dashed var(--color-border);
    border-radius: var(--radius-md);
    padding: var(--space-6);
    text-align: center;
    color: var(--color-muted);
}

/* ---------------------------------------------------------
   Slot cards
--------------------------------------------------------- */

.slot-card {
    border-radius: var(--radius-sm);
    padding: var(--space-3);
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-2);
    border: 1px solid var(--color-border);
    transition: border-color 0.15s ease, opacity 0.15s ease;
}

.slot-card.slot-free {
    background: var(--color-success-bg);
    border-color: var(--color-success-border);
}

.slot-card.slot-free:hover {
    border-color: var(--color-success);
}

.slot-card.slot-booked {
    background: var(--admin-surface-alt);
    border-color: var(--color-border);
    opacity: 0.7;
}

.slot-card.is-submitting {
    opacity: 0.6;
    pointer-events: none;
}

.slot-time {
    font-weight: 700;
    color: var(--color-success-dark);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-2);
}

.slot-status {
    font-size: 0.9rem;
    color: var(--color-muted);
}

.slot-error {
    font-size: 0.85rem;
    color: var(--color-danger);
    display: none;
}

.slot-error.is-visible {
    display: block;
}

.badge {
    font-size: 0.7rem;
    font-weight: 700;
    padding: 2px 8px;
    border-radius: var(--radius-pill);
    background: var(--color-success);
    color: #fff;
}

.badge.badge-booked {
    background: #8a8f96;
}

.slot-card input[type="text"],
.slot-card input[type="email"] {
    width: 100%;
    padding: 8px 10px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--color-border);
    font-size: 0.95rem;
    background: #fff;
    color: var(--color-text);
    font-family: inherit;
}

.slot-card input::placeholder {
    color: #8a8f96;
}

.slot-card input:focus-visible {
    outline: none;
    border-color: var(--color-success);
    box-shadow: 0 0 0 2px var(--color-success-border);
}

.btn-small {
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    border: none;
    background: var(--color-success);
    color: #ffffff;
    font-size: 0.85rem;
    font-weight: 700;
    cursor: pointer;
    justify-self: flex-start;
    transition: background 0.15s ease;
}

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

.btn-small:disabled {
    background: #9ca3af;
    cursor: not-allowed;
}

/* ---------------------------------------------------------
   Buttons (general)
--------------------------------------------------------- */

.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    margin: 0;
    padding: 10px 18px;
    border-radius: var(--radius-sm);
    background: var(--color-primary);
    color: #ffffff;
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 700;
    border: none;
    cursor: pointer;
    transition: background 0.15s ease;
}

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

.btn:active {
    transform: translateY(1px);
}

.btn-outline {
    background: transparent;
    color: var(--admin-text);
    border: 1px solid var(--admin-border);
}

.btn-outline:hover {
    background: var(--admin-surface-alt);
}

.btn-block {
    width: 100%;
    justify-content: center;
}

body.admin .btn {
    background: var(--admin-accent-1);
    box-shadow: none;
    border: none;
}

body.admin .btn:hover {
    background: var(--color-primary-dark);
    box-shadow: none;
    transform: none;
}

body.admin .btn-outline {
    background: transparent;
    box-shadow: none;
}

body.admin .btn-outline:hover {
    background: var(--admin-surface-alt);
    filter: none;
    transform: none;
}

.btn:disabled,
.btn[disabled] {
    opacity: 0.4;
    cursor: not-allowed;
    box-shadow: none;
    filter: none;
    transform: none;
}

/* ---------------------------------------------------------
   Admin layout — conservative, professional real-estate theme
--------------------------------------------------------- */

body.admin {
    background: var(--admin-bg);
    color: var(--admin-text);
    min-height: 100vh;
}

.admin-shell {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: var(--space-2) var(--space-4) var(--space-6);
}

.admin-nav {
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    background: var(--admin-accent-1);
    border-bottom: 3px solid var(--admin-accent-2);
    position: sticky;
    top: 0;
    z-index: 10;
}

.admin-nav-brand {
    font-weight: 700;
    letter-spacing: -0.01em;
    text-decoration: none;
    font-size: 1.1rem;
    color: #ffffff;
}

.admin-nav-links {
    display: flex;
    align-items: center;
    gap: var(--space-2);
    flex-wrap: wrap;
}

.admin-nav-links a {
    color: #ffffff;
    text-decoration: none;
    padding: 7px 14px;
    border-radius: var(--radius-sm);
    font-size: 0.88rem;
    font-weight: 500;
    border: 1px solid transparent;
    transition: background 0.15s ease;
}

.admin-nav-links a:hover {
    background: rgba(255, 255, 255, 0.15);
}

body.admin h1 {
    color: var(--admin-text);
    padding-top: var(--space-2);
    margin: 0 var(--space-4) var(--space-4);
    font-size: clamp(1.5rem, 1.2rem + 1.2vw, 2rem);
    letter-spacing: -0.01em;
    text-align: center;
}

body.admin .admin-shell h1 {
    margin-left: 0;
    margin-right: 0;
}

body.admin .subtitle {
    color: var(--color-muted);
}

/* ---------------------------------------------------------
   Tables (responsive)
--------------------------------------------------------- */

.table-wrap {
    width: 100%;
    overflow-x: auto;
    border-radius: var(--radius-md);
    box-shadow: var(--admin-glow);
    border: 1px solid var(--admin-border);
}

body.admin .table {
    width: 100%;
    min-width: 560px;
    margin: 0;
    border-collapse: collapse;
    background: var(--admin-surface);
    border-radius: var(--radius-md);
    overflow: hidden;
}

body.admin .table th,
body.admin .table td {
    padding: var(--space-3);
    border-bottom: 1px solid var(--admin-border);
    font-size: 0.9rem;
    text-align: left;
}

body.admin .table th {
    background: var(--admin-surface-alt);
    color: var(--color-text);
    text-transform: uppercase;
    letter-spacing: 0.04em;
    font-size: 0.75rem;
}

body.admin .table tr:last-child td {
    border-bottom: none;
}

body.admin .table tr:hover td {
    background: var(--admin-surface-alt);
}

.status-pill {
    display: inline-block;
    padding: 3px 12px;
    border-radius: var(--radius-pill);
    font-size: 0.8rem;
    font-weight: 700;
}

.status-pill.status-yes {
    background: var(--color-success-bg);
    color: var(--color-success-dark);
}

.status-pill.status-no {
    background: var(--color-danger-bg);
    color: var(--color-danger);
}

.table-actions a {
    margin-right: var(--space-2);
    font-size: 0.85rem;
    color: var(--color-primary);
}

.filter-bar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--space-2);
    margin-bottom: var(--space-4);
}

.filter-bar input[type="text"],
.filter-bar select {
    padding: 9px 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--admin-border);
    background: var(--admin-surface);
    color: var(--admin-text);
    font-size: 0.9rem;
    font-family: inherit;
}

/* ---------------------------------------------------------
   Forms
--------------------------------------------------------- */

.form {
    width: 100%;
    max-width: 420px;
    margin: var(--space-5) auto;
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
    background: var(--admin-surface);
    padding: var(--space-5);
    border-radius: var(--radius-md);
    border: 1px solid var(--admin-border);
    box-shadow: var(--admin-glow);
}

.form label {
    display: flex;
    flex-direction: column;
    gap: 4px;
    font-size: 0.9rem;
}

.form label.checkbox {
    flex-direction: row;
    align-items: center;
    gap: var(--space-2);
}

.form input[type="date"],
.form input[type="time"],
.form input[type="number"],
.form input[type="text"],
.form input[type="password"] {
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--admin-border);
    background: var(--admin-surface);
    color: var(--admin-text);
    font-size: 0.95rem;
    font-family: inherit;
}

.form h1 {
    text-align: center;
    margin-bottom: var(--space-2);
    padding-top: 0;
    color: var(--admin-accent-1);
}

.form input:focus-visible {
    outline: none;
    border-color: var(--admin-accent-1);
    box-shadow: 0 0 0 2px rgba(28, 58, 94, 0.2);
}

.form-error {
    color: var(--color-danger);
    font-size: 0.9rem;
    background: var(--color-danger-bg);
    border: 1px solid var(--color-danger-border);
    padding: var(--space-2) var(--space-3);
    border-radius: var(--radius-sm);
}

/* ---------------------------------------------------------
   Responsive breakpoints
--------------------------------------------------------- */

@media (max-width: 640px) {
    .calendar-grid {
        grid-template-columns: 1fr;
    }

    .admin-nav {
        flex-direction: column;
        align-items: stretch;
        text-align: center;
    }

    .form {
        margin: var(--space-4) var(--space-3);
        padding: var(--space-4);
    }

    body.admin .table th,
    body.admin .table td {
        font-size: 0.82rem;
        padding: var(--space-2);
    }
}

/* ---------------------------------------------------------
   Accessibility: theme, font size and colorblind-safe modes
--------------------------------------------------------- */

html[data-theme="dark"] {
    --color-bg: #14181d;
    --color-surface: #1c2126;
    --color-text: #e5e7ea;
    --color-muted: #9aa1a9;
    --color-border: #2b3138;
    --color-primary: #4a7ab0;
    --color-primary-dark: #6693c2;
    --color-success: #4c9868;
    --color-success-dark: #6fb587;
    --color-success-bg: rgba(76, 152, 104, 0.15);
    --color-success-border: rgba(76, 152, 104, 0.4);
    --color-danger: #c96a5f;
    --color-danger-bg: rgba(201, 106, 95, 0.15);
    --color-danger-border: rgba(201, 106, 95, 0.4);

    --admin-bg: #14181d;
    --admin-surface: #1c2126;
    --admin-surface-alt: #20262c;
    --admin-border: #2b3138;
    --admin-text: #e5e7ea;
    --admin-accent-1: #2b4f78;
    --admin-accent-2: #a9863f;
}

html[data-theme="dark"] .slot-card input[type="text"],
html[data-theme="dark"] .slot-card input[type="email"] {
    background: var(--color-surface);
}

html[data-theme="dark"] .slot-card input::placeholder {
    color: var(--color-muted);
}

/* Native Datum-/Zeit-Picker-Icons sind sonst im Dark-Mode schwarz und unsichtbar. */
html[data-theme="dark"] .form input[type="date"],
html[data-theme="dark"] .form input[type="time"] {
    color-scheme: dark;
}

/* Colorblind-safe mode: renders all content in grayscale so meaning never depends on hue.
   The toolbar itself is excluded (its position:fixed would otherwise break, since a
   filter on an ancestor makes that ancestor the containing block for fixed children). */
html[data-colorblind="safe"] body > *:not(.a11y-toolbar) {
    filter: grayscale(1) contrast(1.05);
}

/* Font size steps toggled via the A-/A+ controls. */
html[data-font="sm"] { font-size: 87.5%; }
html[data-font="md"] { font-size: 100%; }
html[data-font="lg"] { font-size: 112.5%; }
html[data-font="xl"] { font-size: 125%; }

/* ---------------------------------------------------------
   Accessibility toolbar
--------------------------------------------------------- */

.a11y-toolbar {
    position: fixed;
    top: 50px;
    right: var(--space-3);
    z-index: 100;
    width: 34px;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 3px;
    padding: 4px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow-md);
}

.a11y-toolbar-handle {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 16px;
    color: var(--color-muted);
    font-size: 0.7rem;
    letter-spacing: 1px;
    cursor: ns-resize;
    touch-action: none;
    user-select: none;
    border-radius: var(--radius-sm);
}

.a11y-toolbar-handle:hover {
    background: var(--color-bg);
}

.a11y-toolbar.is-dragging {
    box-shadow: var(--shadow-md);
}

.a11y-toolbar button {
    appearance: none;
    border: 1px solid transparent;
    background: transparent;
    color: var(--color-text);
    font-size: 0.68rem;
    font-weight: 700;
    line-height: 1;
    padding: 6px 2px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s ease;
}

.a11y-toolbar button svg {
    display: block;
}

.a11y-toolbar .icon-moon {
    display: none;
}

html[data-theme="dark"] .a11y-toolbar .icon-sun {
    display: none;
}

html[data-theme="dark"] .a11y-toolbar .icon-moon {
    display: block;
}

.a11y-toolbar button:hover,
.a11y-toolbar button.is-active {
    background: var(--color-bg);
    border-color: var(--color-border);
}

.a11y-toolbar button:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

@media (max-width: 640px) {
    .a11y-toolbar {
        right: var(--space-3);
    }
}

/* ---------------------------------------------------------
   Footer
--------------------------------------------------------- */

.site-footer {
    text-align: center;
    padding: var(--space-5) var(--space-4);
    color: var(--color-muted);
    font-size: 0.85rem;
    margin-top: auto;
    flex-shrink: 0;
}

.site-footer a {
    color: inherit;
    text-decoration: underline;
}

.admin-pi-link {
    position: fixed;
    right: var(--space-3);
    bottom: var(--space-3);
    z-index: 99;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    color: var(--color-muted);
    font-size: 1rem;
    font-weight: 700;
    text-decoration: none;
    opacity: 0.5;
    transition: opacity 0.15s ease, background 0.15s ease;
}

.admin-pi-link:hover,
.admin-pi-link:focus-visible {
    opacity: 1;
    background: var(--color-bg);
    outline: none;
}
html[data-theme="light"] .admin-pi-link {
    background: rgba(255, 255, 255, 0.6);
}