:root {
    --brand-900: #17346f;
    --brand-800: #23458f;
    --brand-700: #2f57ad;
    --brand-600: #3c69c7;
    --brand-100: #eaf1ff;
    --accent: #20a7a0;
    --accent-dark: #14837e;
    --text-900: #142033;
    --text-700: #42516a;
    --surface: #ffffff;
    --surface-soft: #f5f8fd;
    --border: #dfe7f2;
    --header-height: 88px;
    --page-width: 1320px;
    --shadow-sm: 0 8px 24px rgba(24, 52, 111, 0.08);
    --shadow-md: 0 18px 50px rgba(24, 52, 111, 0.14);
    --radius-sm: 12px;
    --radius-md: 20px;
    --radius-lg: 28px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    min-width: 320px;
    margin: 0;
    padding-top: var(--header-height);
    overflow-x: hidden;
    color: var(--text-900);
    background: var(--surface-soft);
    font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
        "Segoe UI", Roboto, Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    text-rendering: optimizeLegibility;
    -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
p,
ul {
    margin: 0;
}

ul {
    padding: 0;
}

a {
    color: inherit;
}

button,
a {
    -webkit-tap-highlight-color: transparent;
}

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

img,
svg {
    display: block;
    max-width: 100%;
}

section {
    width: 100%;
    scroll-margin-top: calc(var(--header-height) + 16px);
}

:focus-visible {
    outline: 3px solid rgba(60, 105, 199, 0.45);
    outline-offset: 3px;
}

/* =========================
   FIXED HEADER
========================= */

header {
    position: fixed;
    z-index: 1000;
    top: 0;
    right: 0;
    left: 0;

    display: grid;
    grid-template-columns: minmax(190px, 250px) minmax(0, 1fr) auto;
    align-items: center;
    gap: clamp(14px, 2vw, 30px);

    min-height: var(--header-height);
    padding: 0 clamp(22px, 4vw, 68px);

    background: rgba(255, 255, 255, 0.96);
    border-bottom: 1px solid rgba(223, 231, 242, 0.9);
    box-shadow: 0 6px 24px rgba(20, 32, 51, 0.08);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
}

header .header_container {
    display: flex;
    align-items: center;
    min-width: 0;
    height: 100%;
}

header .header_container:nth-child(1) {
    justify-content: flex-start;
}

header .header_container:nth-child(2) {
    justify-content: center;
    width: 100%;
}

header .header_container:nth-child(3) {
    justify-content: flex-end;
}

header img {
    width: min(100%, 215px);
    height: 58px;
    object-fit: contain;
    object-position: left center;
}

.header_nav {
    width: 100%;
}

header nav ul {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: clamp(3px, 0.65vw, 11px);
    width: 100%;
    list-style: none;
}

header nav ul li {
    min-width: 0;
}

header nav ul li a {
    position: relative;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 9px clamp(8px, 0.75vw, 13px);

    color: var(--text-900);
    background: transparent;
    border-radius: 999px;

    font-size: clamp(12px, 0.82vw, 15px);
    font-weight: 650;
    line-height: 1.2;
    text-align: center;
    text-decoration: none;
    white-space: nowrap;

    transition: color 180ms ease, background-color 180ms ease,
        transform 180ms ease, box-shadow 180ms ease;
}

header nav ul li a:hover {
    color: var(--brand-800);
    background: var(--brand-100);
    transform: translateY(-1px);
}

header nav ul li a.active {
    color: #ffffff;
    background: linear-gradient(135deg, var(--brand-800), var(--brand-600));
    box-shadow: 0 8px 18px rgba(47, 87, 173, 0.23);
}

.book a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 46px;
    padding: 11px 19px;

    color: #ffffff;
    background: linear-gradient(135deg, var(--brand-800), var(--brand-600));
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 999px;
    box-shadow: 0 10px 22px rgba(47, 87, 173, 0.22);

    font-size: 14px;
    font-weight: 750;
    line-height: 1.2;
    text-align: center;
    text-decoration: none;
    white-space: nowrap;

    transition: transform 180ms ease, box-shadow 180ms ease,
        background-color 180ms ease;
}

.book a:hover {
    background: linear-gradient(135deg, var(--brand-900), var(--brand-700));
    box-shadow: 0 13px 28px rgba(47, 87, 173, 0.29);
    transform: translateY(-2px);
}

.menu-toggle {
    display: none;
    place-items: center;
    width: 46px;
    height: 46px;
    padding: 0;

    color: var(--brand-800);
    background: var(--brand-100);
    border: 1px solid #d7e3fa;
    border-radius: 13px;
    cursor: pointer;

    font-size: 25px;
    line-height: 1;

    transition: color 180ms ease, background-color 180ms ease,
        transform 180ms ease;
}

.menu-toggle:hover {
    color: #ffffff;
    background: var(--brand-700);
    transform: translateY(-1px);
}

/* =========================
   TABLET / COLLAPSED MENU
   The wide breakpoint is intentional because the navigation
   contains several long labels.
========================= */

@media (max-width: 1180px) {
    :root {
        --header-height: 72px;
    }

    header {
        display: flex;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        max-height: 100dvh;
        min-height: var(--header-height);
        padding: 8px clamp(14px, 3vw, 28px);
        overflow-y: auto;
    }

    header .header_container {
        width: 100%;
        height: auto;
    }

    header .header_container:nth-child(1) {
        justify-content: space-between;
        min-height: 56px;
    }

    header .header_container:nth-child(2) {
        display: block;
        width: 100%;
    }

    header .header_container:nth-child(3) {
        display: none;
        justify-content: center;
        width: 100%;
        padding: 4px 0 10px;
    }

    header .header_container:nth-child(3).active {
        display: flex;
    }

    header img {
        width: 184px;
        height: 46px;
    }

    .menu-toggle {
        display: grid;
    }

    .header_nav {
        display: none;
        width: 100%;
        padding: 5px 0 7px;
    }

    .header_nav.active {
        display: block;
    }

    header nav ul {
        flex-direction: column;
        align-items: stretch;
        gap: 4px;
    }

    header nav ul li,
    header nav ul li a {
        width: 100%;
    }

    header nav ul li a {
        justify-content: flex-start;
        min-height: 44px;
        padding: 11px 14px;
        border-radius: 11px;
        font-size: 15px;
        text-align: left;
        white-space: normal;
    }

    .book a {
        width: min(100%, 380px);
    }
}

@media (max-width: 560px) {
    header {
        padding-right: 12px;
        padding-left: 12px;
    }

    header img {
        width: 154px;
        height: 42px;
    }

    .menu-toggle {
        width: 43px;
        height: 43px;
        border-radius: 12px;
        font-size: 23px;
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}