html, body {
    margin: 0;
    padding: 0;
    height: 100%;
    font-family: "Fira Mono", monospace;
    color: var(--color-main-text-black);
    overflow: hidden;
}

header {
    transition: opacity 0.5s ease, transform 0.5s ease;
}

footer {
    font-size: clamp(18px, 1vw, 26px);
}

header img {
    width: 10%;
    height: auto;
}

header.hidden {
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.5s ease;
    user-select: none;
}

#bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
    z-index: -1;
    background: var(--color-bg-behind);
}

.video-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    z-index: -1;
    transition: filter 0.5s ease, transform 0.5s ease, opacity 3s ease-in-out;
    opacity: 0;
    filter: blur(6px);
    pointer-events: none;
}

.video-bg.active {
    opacity: 1;
}

body.blur .video-bg {
    filter: blur(6px) brightness(0.7);
}

#wrapper {
    position: relative;
    z-index: 1;
    text-align: center;
    height: 80vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    font-size: clamp(24px, 1vw, 30px);
    font-weight: bold;
}

#mini_logo img{
    height: auto;
    width: 15%;
}

nav ul {
    list-style: none;
    padding: 0;
    margin: 2rem 0 0 0;
    display: flex;
    justify-content: center;
    gap: 2rem;
}

nav ul li a {
    color: var(--color-main-text-white);
    text-decoration: none;
    font-weight: bold;
    border: 2px solid rgba(0, 0, 0, 0.8);
    padding: 0.5rem 1rem;
    border-radius: 0.5rem;
    transition: all 0.3s ease;
}

nav ul li a:hover {
    background-color: rgba(0, 0, 0, 0.7);
    border-color: rgba(0, 0, 0, 0.7);
}

section {
    opacity: 0;
    transform: translateY(20px);
    pointer-events: none;
    transition: all 0.5s ease;

    position: absolute;
    top: 15%;
    left: 20%;
    width: 60%;

    max-height: 75vh;
    overflow-y: auto;

    color: var(--color-main-text-white);
    background: rgba(0, 0, 0, 0.3);
    padding: 2rem;
    border-radius: 1rem;
    font-size: clamp(28px, 1vw, 20px);
    text-align: justify;
    box-sizing: border-box;
}

section h1 {
    font-size: clamp(40px, 4vw, 38px);
    text-align: center;
    color: darkgrey;
}
section h2 {
    font-size: clamp(34px, 3.4vw, 32px);
    text-align: center;
    color: darkgrey;
}

section.active {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
    display: block;
}

.split-content {
    display: flex;
    align-items: flex-start;
    gap: 4rem;
    font-size: clamp(26px, 2vw, 24px);
}

.split-content .left, .split-content .right {
    flex: 1;
    text-align: justify;
}

.split-content img {
    display: block;
    margin: 0 auto;
    height: auto;
    border-radius: 0.5rem;
}

.info-content {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 20px;
    opacity: 1;
    visibility: visible;
    overflow: hidden;
    /*transition: opacity 0.5s ease, max-height 0.5s ease, visibility 0.5s ease;*/ /*Плавность (PS: Криво работает)*/
}

.info-content img {
    object-fit: cover;
    align-self: flex-start;
    border-radius: 5%;
}

.info-text {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.hidden-text {
    overflow: hidden;
    max-height: 0;
    opacity: 0;
    transition: max-height 0.5s ease, opacity 0.5s ease;
    margin-top: 0;
    visibility: hidden;
}

.hidden-text.show {
    opacity: 1;
    max-height: 1000px;
    margin-top: 10px;
    visibility: visible;
}

.info-content.hidden {
    opacity: 0;
    max-height: 0;
    overflow: hidden;
    pointer-events: none;
    margin: 0;
    padding: 0;
    /*transition: all 0.4s ease;*/ /*Плавность (PS: Криво работает)*/
}

.close-btn {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: transparent;
    color: var(--color-main-text-white);
    font-size: clamp(60px, 3vw, 64px);
    border: none;
    cursor: pointer;
    z-index: 10;
}

.close-btn:hover {
    color: var(--color-error);
}

.pdf-btn {
    margin-top: 3rem;
    padding-top: 1.5rem;
    border-top: 1px solid rgba(255, 255, 255, 0.2);
    text-align: center;
}

.pdf-btn a {
    display: inline-block;
    padding: 10px 20px;
    background: var(--color-1button);
    color: var(--color-main-text-white);
    text-decoration: none;
    border-radius: 8px;
    font-size: clamp(30px, 2.5vw, 34px);
    margin: 0 10px;
    transition: background 0.3s ease;
}

.pdf-btn a:hover {
    background: var(--color-2button);
}

.checklist {
    list-style: none;
    padding-left: 0;
}

.checklist li::before {
    content: '✔';
    color: var(--color-error);
    margin-right: 0.5rem;
}

.contacts {
    position: fixed;
    bottom: 0;
    width: 100%;
    color: white;
    text-align: center;
    padding: 1rem;
}

/* Адаптивность */
/* Планшеты: ширина 601px – 1024px */
@media (min-width: 601px) and (max-width: 1024px) {
    header img,
    #mini_logo img {
        width: 21%;
    }

    section {
        width: 100%;
        height: 100%;
        top: 0;
        left: auto;
        background: var(--color-nonmain-text-black);
        max-height: none;
    }
}

/* Мобильные устройства: ширина до 600px */
@media (max-width: 600px) {
    header img,
    #mini_logo img {
        width: 30%;
    }

    section {
        width: 100%;
        height: 100%;
        top: 0;
        left: auto;
        background: var(--color-nonmain-text-black);
        max-height: none;
    }
}

/* Низкие экраны: высота до 910px */
@media (max-height: 910px) {
    header img,
    #mini_logo img {
        width: 12%; /* чуть меньше, но не слишком мелко */
    }

    #wrapper {
        height: 80vh;
    }

    section {
        width: 100%;
        height: 100%;
        top: 0;
        left: auto;
        background: var(--color-nonmain-text-black);
        max-height: none;
    }
}

/* Комбинация: мобильные + низкие экраны */
@media (max-width: 600px) and (max-height: 910px) {
    header img,
    #mini_logo img {
        width: 18%; /* под мобильные низкие экраны */
    }

    #wrapper {
        height: 75vh;
    }

    section {
        width: 100%;
        height: 100%;
        top: 0;
        left: auto;
        background: var(--color-nonmain-text-black);
        max-height: none;
    }
}