:root {

    --blue: #405f89;
    --blue-dark: #304b6d;
    --blue-light: #edf1f5;



    --text-muted: rgba(51, 51, 51, 0.58);
    --text-light: rgba(51, 51, 51, 0.4);




    --color-text-number-secondary: rgba(64, 95, 137, 0.45);

    --fs-display: round(clamp(3.25rem, 6.2vw, 6rem), 2px); /* размер всегда будет целым чётным числом от 52px до 96px */
    --lh-display: 0.92
}

/* buttons begin */
.home_button {
    min-height: 3rem;

    padding: 0.8rem 1.35rem;

    display: inline-flex;
    align-items: center;
    justify-content: center;

    border: 1px solid transparent;
    border-radius: 0.5rem; /* 8px */

    font-size: 0.7rem;
    font-weight: var(--fw-bold);
    letter-spacing: 0.8px;
    line-height: 1;
    text-transform: uppercase;

    transition: background 0.2s ease,
    color 0.2s ease,
    border-color 0.2s ease,
    transform 0.2s ease;
}


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


.home_button_primary {
    background: var(--color-primary);
    color: #ffffff;
}


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


.home_button_secondary {
    background: transparent;
    color: var(--color-primary);

    border-color: rgba(64, 95, 137, 0.3);
}


.home_button_secondary:hover {
    background: var(--color-primary);
    color: #ffffff;
    border-color: var(--color-primary);
}


.home_button_light {
    background: #ffffff;
    color: var(--color-primary);
}


.home_button_light:hover {
    background: var(--color-accent);
}



.home_practice .home_button,
.home_olympiads .home_button {
    margin-top: 1rem;
}
/* buttons end */

/* sections begin */
.section {
    padding: 2rem 0; /* 32px 0 */
}

.section > header {
    display: grid;
    grid-template-columns: 3rem 1fr; /* 48px 1fr */
    gap: 0 1rem; /* 0 16px */
    margin-bottom: 1.875rem; /* 30px */
}

.section > header h2 {
    grid-row: 1 / 2;
    grid-column: 2 / 3;
    margin-bottom: 0.5rem; /* 8px */
}

.section_description {
    grid-row: 2 / 3;
    grid-column: 2 / 3;
    color: rgba(51, 51, 51, 0.58);
}

.section_number {
    grid-row: 1 / 2;
    grid-column: 1 / 1;
    padding-top: 0.25rem; /* 4px */
    color: var(--color-primary);
    font-size: 0.75rem; /* 12px */
    font-weight: var(--fw-bold);
    letter-spacing: 0.0625rem; /* 1px */
}
/* sections end */

/* hero begin */
#hero {
    min-height: calc(100vh - 4rem);
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(20rem, 0.9fr);
    gap: 4rem;
    align-items: center;
}

#hero_content {
    display: flex;
    flex-direction: column;
    gap: 2rem; /* 32px */
}

#hero_label {
    margin: 0;
    color: var(--color-primary);
    font-size: 0.75rem; /* 12px */
    font-weight: var(--fw-bold);
    letter-spacing: 0.0625rem /* 1px */;
    text-transform: uppercase;
}

#hero_content h1 {
    margin: 0;
    font-size: var(--fs-display);
    letter-spacing: var(--ls-display);
    line-height: var(--lh-display);
}

#hero_content h1 span {
    display: inline-block;
    color: var(--color-primary);
}

#hero_description {
    max-width: 35rem; /* 560px */
    margin: 0;
    font-size: 1rem; /* 16px */
    color: var(--color-text-main);
}

#hero_visual {
    min-height: 29rem;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-dark));
    border-radius: 0.5rem; /* 8px */
    box-shadow: 0 1.5rem 4rem rgba(48, 75, 109, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

.hero_visual_formula {
    position: absolute;
    color: var(--color-text-light);
    font-size: 1rem; /* 16px */
    font-weight: var(--fw-light);
    line-height: 1;
    text-shadow: 0 0.0625rem 0.125rem var(--color-shadow-light); /* 0 1px 2px */
    white-space: nowrap;
}

.hero_visual_formula_1 {
    top: 13%;
    left: 10%;
}

.hero_visual_formula_2 {
    top: 28%;
    right: 10%;
}

.hero_visual_formula_3 {
    bottom: 18%;
    left: 9%;
}

.hero_visual_formula_4 {
    bottom: 11%;
    right: 18%;
}

.hero_visual_formula_main {
    position: relative;
    color: var(--color-text-white);
    font-size: 11rem;
    font-weight: var(--fw-light);
}

.hero_visual_line {
    position: absolute;
    width: 13rem;
    height: 0.0625rem; /* 1px */
    background: rgba(255, 255, 255, 0.14);
}

.hero_visual_line_1 {
    top: 30%;
    left: -2rem;
    transform: rotate(-30deg);
}

.hero_visual_line_2 {
    right: -2rem;
    bottom: 29%;
    transform: rotate(30deg);
}
/* hero end */

/* classes begin */
#classes_grid {
    margin: 0;
    padding: 0;
    list-style: none;
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    border: 0.0625rem solid var(--color-border-gray); /* 1px */
    border-radius: 0.5rem; /* 8px */
    overflow: hidden;
}

.class_card a {
    aspect-ratio: 16 / 9;
    padding: 1rem;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    background: var(--color-bg-white);
    text-decoration: none;
    transition: background 0.2s ease, color 0.2s ease;
}

.class_card a:hover {
    background: var(--color-primary);
    color: var(--color-text-white);
}

.class_card:last-child {
    grid-column: span 2;
}

.class_card:last-child a {
    aspect-ratio: 32 / 9;
}

.class_card_number {
    color: var(--color-text-number-secondary);
    font-size: 0.625rem; /* 10px */
    font-weight: var(--fw-bold);
}

.class_card:hover .class_card_number {
    color: rgba(255, 255, 255, 0.65);
}

.class_card_name {
    font-size: 1.125rem;
    font-weight: var(--fw-semibold);
}

.class_card_subjects {
    color: rgba(51, 51, 51, 0.52);
    font-size: 0.625rem;
    text-transform: uppercase;
}

.class_card:hover .class_card_subjects {
    color: rgba(255, 255, 255, 0.7);
}
/* classes end */

/* subjects begin */
#subjects {
    scroll-margin-top: 4rem; /* прокрутится не доезжая 4rem до блока */
    border-top: 0.0625rem solid var(--color-border-gray); /* 1px */
}

.list_class_card {
    min-height: 12rem; /* 192px */;
    padding: 1rem 0; /* 16px 0 */
    display: grid;
    grid-template-columns: 3rem minmax(16.25rem, 1fr) minmax(22.5rem, .9fr); /* 48px 260px 360px */
    gap: 1rem; /* 16px */
    align-items: center;
    border-bottom: 0.0625rem solid var(--color-border-gray); /* 1px */
}

.list_class_card:last-child {
    border: none;
}

.list_class_card_number {
    align-self: start;
    color: var(--color-text-number-secondary);
    font-size: 0.625rem; /* 10px */
    font-weight: var(--fw-bold);
}

.list_class_card_main_header span {
    display: block;
    margin-bottom: 10px;
    color: var(--blue);
    font-size: 0.625rem; /* 10px */
    font-weight: var(--fw-bold);
}

.list_class_card_main_header h2 {
    margin: 0;
    font-weight: var(--fw-semibold);
}

.list_class_card_main > p {
    max-width: 26.25rem; /* 420px */
    margin: 1rem 0 0;
    color: var(--text-muted);
    font-size: 0.875rem; /* 14px */
}

.list_class_card_subjects {
    margin: 0;
    padding: 0;
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.5rem; /* 8px */
}

.list_class_card_subjects_link {
    min-height: 4.375rem; /* 70px */
    padding: 0.75rem 1rem; /* 12px 16px */
    display: grid;
    grid-template-columns: 2.75rem 1fr auto; /* 44px */
    gap: 1rem;
    align-items: center;
    background: var(--color-bg-white);
    border: 0.0625rem solid var(--color-border-gray); /* 1px */
    border-radius: 0.5rem; /* 8px */
    transition: background .2s ease, border-color .2s ease;
}

.list_class_card_subjects_link:hover {
    background: var(--blue-light);
    border-color: rgba(64, 95, 137, .25);
}

.list_class_card_subjects_link_symbol {
    width: 2.25rem; /* 36px */
    height: 2.25rem; /* 36px */
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--blue-light);
    border-radius: 0.5rem; /* 8px */
    color: var(--blue);
    font-size: 1rem;
    font-weight: var(--fw-regular);
}

.list_class_card_subjects_link_text {
    min-width: 0;
    display: flex;
    flex-direction: column;
    gap: 0.125rem; /* 2px */
}

.list_class_card_subjects_link_text strong {
    font-size: 0.875rem; /* 14px */
    font-weight: var(--fw-bold);
}

.list_class_card_subjects_link_text small {
    color: var(--text-muted);
    font-size: 0.625rem; /* 10px */
    overflow: hidden;
    white-space: nowrap;
    text-overflow: ellipsis;
}

.list_class_card_subjects_link svg {
    width: 1.5rem; /* 24px */;
    fill: var(--color-primary);
    transition: transform .2s ease;
}

.list_class_card_subjects_link:hover svg {
    transform: translateX(4px);
}
/* subjects end */

/* final cta begin */
#final {
    min-height: 30rem;
    margin-top: 2rem;
    padding: 4rem;
    background: var(--color-primary);
    border-radius: 0.5rem; /* 8px */
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
}

#final_formula {
    position: absolute;
}

#final_formula svg {
    display: block;
    height: 28rem;
    fill: rgba(255, 255, 255, 0.06);
}

#final_content {
    position: relative;
    z-index: 2;
}

#final_content > span {
    color: var(--color-text-light);
    font-size: 0.625rem; /* 10px */
    font-weight: var(--fw-bold);
}

#final_content h2 {
    margin: 1rem 0;
    color: var(--color-text-white);
    font-size: round(clamp(2.25rem, 5vw, 4rem), 2px); /* размер всегда будет целым чётным числом от 36px до 64px */
    font-weight: var(--fw-light);
}

#final_content h2 span {
    display: block;
}

#final_content p {
    margin-bottom: 0;
    color: var(--color-text-light);
}

#final_content a {
    margin-top: 2rem;
    display: inline-flex;
    gap: 0.5rem; /* 8px */
}

#final_content a svg {
    width: 1.5rem; /* 24px */;
    fill: var(--color-primary);
}
/* final cta end */

/* seo begin */
#seo {
    max-width: 52rem;
    margin: 4rem auto 0;
    text-align: center;
}

#seo h2 {
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

#seo p {
    margin-bottom: 0;
    color: rgba(51, 51, 51, 0.58);
    font-size: 0.875rem; /* 14px */
}
/* seo end */

/* media queries begin */
@media (width < 1280px) {
    #classes_grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

@media (width < 992px) {
    .section header {
        grid-template-columns: 2rem 1fr;
    }

    #hero {
        grid-template-columns: 1fr;
        min-height: auto;
    }

    #hero_visual {
        min-height: 24rem;
    }

    .list_class_card {
        grid-template-columns: 2rem 1fr; /* 32px */
    }

    .list_class_card_subjects {
        grid-column: 2;
    }
}

@media (width < 768px) {
    .section header {
        grid-template-columns: 1rem 1fr;
    }

    #classes_grid {
        grid-template-columns: repeat(3, 1fr);
    }

    .list_class_card {
        grid-template-columns: 1rem 1fr; /* 32px */
    }

    .list_class_card_subjects_link {
        grid-template-columns: 2rem 1fr auto; /* 32px */
        padding: 0.5rem; /* 8px */
    }

    .list_class_card_subjects_link_symbol {
        width: 2rem; /* 32px */
        height: 2rem; /* 32px */
    }

    #final {
        padding: 3rem 2rem;
    }
}

@media (width < 600px) {
    #hero_description {
        font-size: 0.875rem; /* 14px */
    }

    #hero_visual {
        min-height: 18rem;
        aspect-ratio: 1 / 1;
    }

    .hero_visual_formula_main {
        font-size: 8rem;
    }

    #classes_grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .class_card a {
        padding: 0.875rem; /* 14px */
    }

    #final {
        padding: 2.5rem 1.5rem;
    }
}

@media (width < 480px) {}
/* media queries end */