/* ==============================================
   Shared UI layer
   Foundations, components and small composition
   helpers used across public and admin templates.

   Page/domain styles remain in their own files. New UI should be assembled
   from this layer first and only add page CSS for genuinely unique behavior.
   ============================================== */

/* ===== Document foundations ===== */
html {
    accent-color: var(--accent);
}

body {
    font-family: var(--font-sans);
    line-height: var(--leading-normal);
}

button,
input,
select,
textarea {
    font: inherit;
}

img,
picture,
video,
canvas,
svg {
    max-width: 100%;
}

[hidden] {
    display: none !important;
}

::selection {
    color: var(--clr-cream);
    background: var(--clr-accent);
}

.skip-link {
    position: fixed;
    top: var(--space-2);
    left: var(--space-2);
    z-index: 2000;
    padding: var(--space-2) var(--space-3);
    color: #fff;
    background: var(--accent-red);
    border-radius: var(--radius-sm);
    transform: translateY(calc(-100% - var(--space-4)));
    transition: transform var(--duration-fast) var(--ease-standard);
}

.skip-link:focus {
    color: #fff;
    text-decoration: none;
    transform: translateY(0);
}

.skip-target {
    display: block;
    scroll-margin-top: calc(var(--control-height) * 2 + var(--space-4));
}

/* ===== Layout primitives ===== */
.container {
    max-width: var(--content-default);
    padding-inline: var(--gutter);
}

.home-page .container {
    max-width: var(--content-home);
}

.container:has(> .post-content) {
    max-width: var(--content-wide);
}

.ui-stack {
    display: flex;
    flex-direction: column;
    gap: var(--stack-gap, var(--space-4));
}

.ui-cluster,
.ui-actions {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: var(--cluster-gap, var(--space-2));
}

.ui-actions-end {
    justify-content: flex-end;
}

.ui-split {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-4);
}

.ui-split-main {
    min-width: 0;
    flex: 1 1 auto;
}

.ui-section-gap {
    margin-top: var(--space-4);
}

.ui-table-scroll {
    max-width: 100%;
    overflow-x: auto;
    overscroll-behavior-x: contain;
}

.box:has(> .posts-table) {
    overflow-x: auto;
}

/* ===== State and text helpers ===== */
.is-hidden {
    display: none !important;
}

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

.ui-muted,
.form-hint {
    color: var(--text-muted);
}

.form-hint {
    display: block;
    margin-top: var(--space-1);
    font-size: var(--text-sm);
    line-height: 1.45;
}

.ui-auth-switch {
    margin-top: var(--space-5);
    text-align: center;
}

.ui-full-width {
    width: 100%;
}

.ui-inline-form {
    display: inline-flex;
    margin: 0;
}

.post-nav-left .ui-inline-form {
    margin-left: var(--space-2);
}

/* ===== Shared surfaces ===== */
.box,
.post-content,
.login-box,
.stat-box,
.link-modal {
    border-radius: var(--radius-md);
}

.box,
.post-content,
.login-box {
    box-shadow: var(--shadow);
}

/* ===== Controls ===== */
.btn {
    min-height: var(--control-height);
    padding-inline: var(--space-4);
    border-radius: var(--radius-sm);
    transition:
        color var(--duration-fast) var(--ease-standard),
        background-color var(--duration-fast) var(--ease-standard),
        border-color var(--duration-fast) var(--ease-standard),
        transform var(--duration-fast) var(--ease-standard);
}

.btn:hover:not(:disabled) {
    transform: translateY(-1px);
}

.btn:active:not(:disabled) {
    transform: translateY(0);
}

.btn-small {
    min-height: var(--control-height-sm);
}

.form-group input,
.form-group select,
.form-group textarea {
    border-radius: var(--radius-sm);
    transition:
        border-color var(--duration-fast) var(--ease-standard),
        box-shadow var(--duration-fast) var(--ease-standard),
        background-color var(--duration-fast) var(--ease-standard);
}

.form-group input:not([type='checkbox']):not([type='radio']),
.form-group select {
    min-height: var(--control-height);
}

.form-group input:focus-visible,
.form-group select:focus-visible,
.form-group textarea:focus-visible {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--focus-ring);
}

/* ===== Feedback ===== */
.message {
    border-radius: var(--radius-sm);
}

.message:empty {
    display: none;
}

.message-info {
    color: var(--info-text);
    background-color: var(--info-bg);
    border-color: var(--info-border);
}

/* ===== Tables ===== */
.posts-table-wide {
    margin-top: var(--space-4);
}

.posts-table .col-id {
    width: 10%;
}

.posts-table .col-title {
    width: 50%;
}

.posts-table .col-date,
.posts-table .col-actions {
    width: 20%;
}

/* ===== Modal behavior ===== */
.link-overlay[aria-hidden='false'] {
    display: flex;
}

/* ===== Navigation details ===== */
.theme-toggle,
.lang-btn {
    min-width: var(--control-height);
    min-height: var(--control-height);
}

.theme-toggle-icon {
    display: inline-block;
    font-size: 1rem;
    line-height: 1;
}

.lang-menu {
    border-radius: var(--radius-sm);
}

/* ===== Responsive and user preferences ===== */
@media (max-width: 768px) {
    .container {
        padding-inline: 0;
    }

    .ui-split {
        gap: var(--space-3);
    }

    .login-container {
        margin: var(--space-8) var(--gutter);
    }

    .login-box {
        padding: var(--space-6);
    }

    .ui-table-scroll {
        border-inline: 0;
    }
}

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

@media (forced-colors: active) {
    .btn,
    .message,
    .box,
    .post-content {
        border-color: CanvasText;
    }
}
