/* ==========================================================================
   Interactions — links, buttons, forms, focus, motion
   ========================================================================== */

/* Shared interactive transitions (transform/opacity only — no layout shift) */
.nav__link,
.cases__link,
.footer__link,
.footer__back-top,
.contacts__submit,
.header__logo,
.footer__logo,
.cases__item {
    -webkit-tap-highlight-color: transparent;
}

@media (prefers-reduced-motion: no-preference) {
    .nav__link,
    .cases__link,
    .footer__link,
    .footer__back-top,
    .contacts__submit,
    .header__logo,
    .footer__logo {
        transition:
            transform var(--motion-duration-base) var(--motion-ease-out),
            opacity var(--motion-duration-base) var(--motion-ease-out),
            color var(--motion-duration-base) var(--motion-ease-out),
            background-color var(--motion-duration-base) var(--motion-ease-out),
            border-color var(--motion-duration-base) var(--motion-ease-out),
            box-shadow var(--motion-duration-base) var(--motion-ease-out);
    }

    .contacts__input {
        transition:
            opacity var(--motion-duration-base) var(--motion-ease-out),
            box-shadow var(--motion-duration-base) var(--motion-ease-out);
    }

    .cases__item {
        transition: transform var(--motion-duration-slow) var(--motion-ease-out);
    }
}

/* Focus rings — links and logos on light backgrounds */
.nav__link:focus-visible,
.cases__link:focus-visible,
.header__logo:focus-visible,
.footer__logo:focus-visible {
    outline: var(--focus-ring-width) solid var(--focus-ring-color-dark);
    outline-offset: var(--focus-ring-offset);
}

/* Focus rings — dark sections and primary actions */
.footer__link:focus-visible,
.footer__back-top:focus-visible,
.contacts__submit:focus-visible,
.contacts__input:focus-visible {
    outline: var(--focus-ring-width) solid var(--focus-ring-color);
    outline-offset: var(--focus-ring-offset);
}

/* Navigation links — underline draw + subtle lift */
.nav__link {
    position: relative;
    display: inline-block;
    transform-origin: center right;
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .nav__link::after {
        content: "";
        position: absolute;
        right: 0;
        bottom: -4px;
        width: 100%;
        height: 2px;
        background-color: currentColor;
        transform: scaleX(0);
        transform-origin: right center;
        transition: transform var(--motion-duration-base) var(--motion-ease-out);
    }

    .nav__link:hover {
        opacity: 0.85;
        transform: scale(var(--interaction-scale-hover));
    }

    .nav__link:hover::after {
        transform: scaleX(1);
        transform-origin: left center;
    }
}

@media (hover: hover) {
    .nav__link:hover {
        opacity: 0.85;
    }
}

.nav__link:active {
    transform: scale(var(--interaction-scale-active));
}

/* Logo links */
.header__logo,
.footer__logo {
    display: inline-block;
    line-height: 0;
    transform-origin: center center;
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .header__logo:hover,
    .footer__logo:hover {
        opacity: 0.88;
        transform: scale(var(--interaction-scale-hover));
    }
}

@media (hover: hover) {
    .header__logo:hover,
    .footer__logo:hover {
        opacity: 0.88;
    }
}

.header__logo:active,
.footer__logo:active {
    transform: scale(var(--interaction-scale-active));
}

/* Cases link — dark section */
.cases__link {
    position: relative;
    display: inline-block;
    transform-origin: center center;
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .cases__link::after {
        content: "";
        position: absolute;
        left: 0;
        bottom: -3px;
        width: 100%;
        height: 1px;
        background-color: currentColor;
        transform: scaleX(0);
        transform-origin: right center;
        transition: transform var(--motion-duration-base) var(--motion-ease-out);
    }

    .cases__link:hover {
        opacity: 0.9;
        transform: scale(var(--interaction-scale-hover));
    }

    .cases__link:hover::after {
        transform: scaleX(1);
        transform-origin: left center;
    }
}

@media (hover: hover) {
    .cases__link:hover {
        opacity: 0.9;
    }
}

.cases__link:active {
    transform: scale(var(--interaction-scale-active));
}

/* Footer navigation links */
.footer__link {
    position: relative;
    display: inline-block;
    transform-origin: center left;
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .footer__link::after {
        content: "";
        position: absolute;
        left: 0;
        bottom: -3px;
        width: 100%;
        height: 1px;
        background-color: #d6ff63;
        transform: scaleX(0);
        transform-origin: left center;
        transition: transform var(--motion-duration-base) var(--motion-ease-out);
    }

    .footer__link:hover {
        color: #d6ff63;
        transform: translateX(2px);
    }

    .footer__link:hover::after {
        transform: scaleX(1);
    }
}

@media (hover: hover) {
    .footer__link:hover {
        color: #d6ff63;
    }
}

.footer__link:active {
    transform: translateX(0) scale(var(--interaction-scale-active));
}

/* Primary buttons — interaction states only (base styles in main.css) */
.contacts__submit,
.footer__back-top {
    transform-origin: center center;
}

@media (hover: hover) {
    .contacts__submit:hover:not(:disabled):not(.is-submitting) {
        opacity: 0.82;
    }

    .footer__back-top:hover {
        opacity: 0.92;
    }
}

@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .contacts__submit:hover:not(:disabled):not(.is-submitting) {
        transform: scale(var(--interaction-scale-hover));
    }

    .footer__back-top:hover {
        transform: scale(var(--interaction-scale-hover));
        box-shadow: 0 4px 16px rgba(214, 255, 99, 0.18);
    }
}

.contacts__submit:active:not(:disabled):not(.is-submitting),
.footer__back-top:active {
    opacity: 0.75;
}

@media (prefers-reduced-motion: no-preference) {
    .contacts__submit:active:not(:disabled):not(.is-submitting),
    .footer__back-top:active {
        transform: scale(var(--interaction-scale-active));
    }

    .footer__back-top:active {
        box-shadow: none;
    }
}

.contacts__submit:focus-visible,
.footer__back-top:focus-visible {
    opacity: 1;
}

.contacts__submit:disabled,
.contacts__submit.is-submitting {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

/* Form inputs — underline via inset shadow (constant 2px, no width changes) */
.contacts__input:hover:not(:focus-visible):not(.is-invalid) {
    box-shadow: inset 0 -2px 0 0 var(--input-border-hover);
}

.contacts__input:focus-visible {
    box-shadow:
        inset 0 -2px 0 0 var(--input-border-focus),
        var(--input-glow-focus);
}

.contacts__input.is-valid:not(:focus-visible) {
    box-shadow: inset 0 -2px 0 0 var(--input-border-valid);
}

.contacts__input.is-invalid:not(:focus-visible) {
    box-shadow:
        inset 0 -2px 0 0 var(--input-border-error),
        0 4px 16px rgba(255, 112, 112, 0.1);
}

.contacts__input.is-invalid:focus-visible {
    outline-color: var(--input-border-error);
    box-shadow:
        inset 0 -2px 0 0 var(--input-border-error),
        0 4px 16px rgba(255, 112, 112, 0.1);
}

.contacts__field-message {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    margin: 0;
    min-height: 1.25rem;
    font-family: var(--font-family-mono);
    font-size: 12px;
    font-weight: 600;
    line-height: 1.4;
    text-align: right;
    color: transparent;
}

.contacts__field-message.is-visible {
    color: var(--input-border-error);
}

.contacts__field-message.is-success {
    color: var(--input-border-valid);
}

/* Cases cards — subtle lift */
@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .cases__item:hover {
        transform: translateY(-4px);
    }

    .cases__item-media:hover .cases__item-image {
        filter: grayscale(var(--cases-image-grayscale)) brightness(1.06);
        transform: scale(1.03);
    }
}

@media (hover: hover) {
    .cases__item-media:hover .cases__item-image {
        filter: grayscale(var(--cases-image-grayscale)) brightness(1.06);
    }
}

/* About cards — minimal hover feedback on dark section */
@media (hover: hover) and (prefers-reduced-motion: no-preference) {
    .about__card {
        transition: transform var(--motion-duration-base) var(--motion-ease-out);
    }

    .about__card:hover {
        transform: translateY(-2px);
    }

    .about__card:hover .about__card-line {
        border-top-color: #d6ff63;
        transition: border-color var(--motion-duration-base) var(--motion-ease-out);
    }
}

.about__card-line {
    transition: border-color var(--motion-duration-base) var(--motion-ease-out);
}

/* Reduced motion — disable decorative interaction motion */
@media (prefers-reduced-motion: reduce) {
    .nav__link::after,
    .cases__link::after,
    .footer__link::after {
        transition: none;
    }

    .nav__link:hover::after,
    .cases__link:hover::after,
    .footer__link:hover::after {
        transform: scaleX(1);
    }

    .nav__link:active,
    .cases__link:active,
    .footer__link:active,
    .contacts__submit:active,
    .footer__back-top:active,
    .header__logo:active,
    .footer__logo:active,
    .cases__item:hover,
    .about__card:hover {
        transform: none;
    }
}