/*
 * Reset, typography and the small set of components every page shares.
 * Written RTL-first: `start`/`end` logical properties throughout, never
 * left/right, so a future LTR locale needs no stylesheet changes.
 */

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

html {
    -webkit-text-size-adjust: 100%;
}

body {
    margin: 0;
    min-height: 100vh;
    font-family: var(--font-body);
    font-size: 15px;
    line-height: 1.75;
    color: var(--text-primary);
    /* Three light pools at fixed points, over the vertical wash. Placed rather
     * than centred: a single symmetrical glow reads as a gradient, three
     * off-centre ones read as light coming from somewhere. */
    background:
        /* Brickwork in hairlines (the --brick token, one per theme), like
         * MedoFast's ground. It is barely visible on its own -- which is the
         * point. A flat ground reads as a blank canvas with boxes dropped on
         * it; a textured one reads as a surface the cards are resting on. */
        var(--brick),
        radial-gradient(circle at 12% 8%, var(--aura-1), transparent 26%),
        radial-gradient(circle at 88% 12%, var(--aura-2), transparent 20%),
        radial-gradient(circle at 52% 62%, var(--aura-3), transparent 34%),
        radial-gradient(120% 80% at 50% 0%, var(--bg-aura-start), transparent 60%),
        linear-gradient(180deg, var(--bg-aura-end), var(--bg-body) 40%);
    background-attachment: fixed;
}

h1, h2, h3, h4 {
    margin: 0 0 var(--space-3);
    line-height: 1.35;
    font-weight: 700;
}

h1 { font-size: 1.65rem; }
h2 { font-size: 1.3rem; }
h3 { font-size: 1.05rem; }

p {
    margin: 0 0 var(--space-3);
}

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

a:hover {
    text-decoration: underline;
}

img {
    max-width: 100%;
    height: auto;
}

/* The `hidden` attribute is how pages hide things, and every component below
 * that sets `display` would otherwise silently override it -- which is how a
 * hidden error notice ends up visible on a freshly loaded form. */
[hidden] {
    display: none !important;
}

/* Every interactive element gets the same visible focus treatment. Removing
 * it makes the site unusable by keyboard, which is not a trade we make. */
:focus-visible {
    outline: 3px solid var(--focus-ring);
    outline-offset: 2px;
    border-radius: var(--radius-sm);
}

.f-skip {
    position: absolute;
    inset-inline-start: var(--space-4);
    top: -60px;
    z-index: 100;
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-sm);
    background: var(--accent);
    color: var(--text-on-accent);
    transition: top 0.15s ease;
}

.f-skip:focus {
    top: var(--space-3);
}

.f-page {
    width: min(100% - 2 * var(--space-4), var(--content-width));
    margin-inline: auto;
    padding-block: var(--space-6) var(--space-7);
}

.f-card {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-soft);
    padding: var(--space-5);
}

.f-muted {
    color: var(--text-secondary);
}

.f-tiny {
    font-size: 0.82rem;
    color: var(--text-tertiary);
}

/* Buttons */

.f-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    min-height: 42px;
    padding: var(--space-2) var(--space-5);
    border: 1px solid transparent;
    border-radius: var(--radius-md);
    font: inherit;
    font-weight: 600;
    cursor: pointer;
    background: var(--surface-strong);
    color: var(--text-primary);
    transition:
        background var(--motion-fast) var(--ease),
        border-color var(--motion-fast) var(--ease),
        box-shadow var(--motion-base) var(--ease),
        transform var(--motion-fast) var(--ease),
        opacity var(--motion-fast) var(--ease);
}

.f-btn:hover:not(:disabled) {
    background: var(--surface-inset);
    text-decoration: none;
}

/* A button that acknowledges being pressed. One pixel is enough -- the point
 * is that something happened, not that it moved. */
.f-btn:active:not(:disabled) {
    transform: translateY(1px);
}

.f-btn:disabled,
.f-btn[aria-disabled="true"] {
    opacity: 0.55;
    cursor: not-allowed;
}

.f-btn--primary {
    background: var(--accent-gradient);
    color: var(--text-on-accent);
    box-shadow: var(--shadow-accent);
}

.f-btn--primary:hover:not(:disabled) {
    background: var(--accent-strong);
}

/* A press always happens while hovering, and `.f-btn--primary:hover` above
 * has the same specificity as the generic `.f-btn:active` lift -- so without
 * restating the transform here, source order would let hover win and a primary
 * button would never appear to depress. */
.f-btn--primary:active:not(:disabled) {
    transform: translateY(1px);
    box-shadow: var(--shadow-accent);
}

.f-btn--ghost {
    background: var(--surface);
    border-color: var(--border-strong);
    box-shadow: var(--shadow-soft);
}

.f-btn--ghost:hover:not(:disabled) {
    border-color: var(--accent);
    color: var(--accent);
}

.f-btn--block {
    width: 100%;
}

/* Forms */

.f-field {
    display: block;
    margin-bottom: var(--space-4);
}

.f-field__label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 600;
    font-size: 0.92rem;
}

.f-field__hint {
    margin-top: var(--space-1);
    font-size: 0.82rem;
    color: var(--text-tertiary);
}

.f-input {
    width: 100%;
    min-height: 46px;
    padding: var(--space-2) var(--space-4);
    font: inherit;
    color: var(--text-primary);
    background: var(--surface-muted);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

.f-input:focus {
    border-color: var(--accent);
}

.f-input[aria-invalid="true"] {
    border-color: var(--danger);
}

/* Notices. `role` is set in markup; the class only carries the colour. */

.f-notice {
    display: flex;
    gap: var(--space-3);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-md);
    border: 1px solid var(--border);
    background: var(--surface-muted);
    margin-bottom: var(--space-4);
}

.f-notice--error {
    border-color: var(--danger);
    background: var(--danger-soft);
}

.f-notice--warning {
    border-color: var(--warning);
    background: var(--warning-soft);
}

.f-notice--success {
    border-color: var(--success);
    background: var(--success-soft);
}

.f-notice__body {
    flex: 1;
}

.f-notice__title {
    font-weight: 700;
    margin-bottom: var(--space-1);
}

.f-notice p:last-child {
    margin-bottom: 0;
}

/* Empty states -- used wherever a list has nothing in it. A blank area with
 * no explanation reads as a broken page, so this always says why. */

.f-empty {
    text-align: center;
    padding: var(--space-6) var(--space-4);
    color: var(--text-secondary);
}

.f-empty__title {
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-2);
}

.f-visually-hidden {
    position: absolute;
    width: 1px;
    height: 1px;
    margin: -1px;
    padding: 0;
    overflow: hidden;
    clip-path: inset(50%);
    white-space: nowrap;
}

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

/* ------------------------------------------------------------ footer */

/* The lantern mark, wherever it appears. */
.f-lantern {
    width: 30px;
    height: 30px;
    color: var(--accent);
    flex: none;
}

.f-footer {
    margin-top: var(--space-7);
    border-top: 1px solid var(--border);
    background: var(--surface);
    color: var(--text-tertiary);
    font-size: var(--text-sm);
}

.f-footer__inner {
    display: grid;
    grid-template-columns: minmax(200px, 1.2fr) 3fr;
    gap: var(--space-6);
    width: min(100% - 2 * var(--space-4), var(--content-width));
    margin-inline: auto;
    padding-block: var(--space-6) var(--space-5);
}

.f-footer__brand {
    display: grid;
    grid-template-columns: auto 1fr;
    align-items: center;
    align-content: start;
    gap: var(--space-2) var(--space-2);
}

.f-footer__brand .f-lantern {
    width: 28px;
    height: 28px;
    color: var(--accent);
}

.f-footer__brand span {
    display: grid;
    line-height: 1.5;
}

.f-footer__brand strong {
    color: var(--text-primary);
    font-weight: var(--weight-strong);
    font-size: var(--text-base);
}

.f-footer__brand small {
    font-size: var(--text-xs);
}

.f-footer__brand p {
    grid-column: 1 / -1;
    margin: var(--space-2) 0 0;
    line-height: 1.9;
    max-width: 34ch;
}

.f-footer__links {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
    gap: var(--space-5);
}

.f-footer__group h2 {
    margin: 0 0 var(--space-3);
    color: var(--text-primary);
    font-size: var(--text-sm);
    font-weight: var(--weight-strong);
}

.f-footer__group ul {
    display: grid;
    gap: var(--space-2);
    margin: 0;
    padding: 0;
    list-style: none;
}

.f-footer__group a {
    color: var(--text-secondary);
}

.f-footer__group a:hover {
    color: var(--accent);
    text-decoration: none;
}

.f-footer__base {
    display: flex;
    justify-content: space-between;
    gap: var(--space-4);
    width: min(100% - 2 * var(--space-4), var(--content-width));
    margin-inline: auto;
    padding-block: var(--space-4);
    border-top: 1px solid var(--border);
    font-size: var(--text-xs);
}

.f-footer__base a {
    color: var(--text-tertiary);
}

@media (max-width: 720px) {
    .f-footer__inner {
        grid-template-columns: 1fr;
        gap: var(--space-5);
    }

    .f-footer__links {
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: var(--space-5) var(--space-4);
    }
}

/* A quieter paper surface keeps long study sessions readable. */
body {
    background: var(--bg-body);
}

.f-page {
    padding-block: clamp(24px, 4vw, 48px) 64px;
}

.f-card {
    border-color: var(--border-strong);
    box-shadow: var(--shadow-soft);
}

.f-btn {
    min-height: 46px;
    font-weight: 700;
}

.f-input {
    background: var(--surface);
    border-color: var(--border-strong);
}

.f-footer {
    margin-top: 64px;
    background: var(--surface-muted);
}