/*
 * Skin: christine (Christine Stiefermann, Systemisches Business Coaching)
 * Source: christine-stiefermann.de (Elementor kit + page CSS), docs/DESIGN_SYSTEM.md 3.2
 *
 * Bright and personal: signal-yellow header band, navy text, Fira Sans Light with Lato Bold
 * section headings, square tiles with an overlapping white label button, slanted section
 * edges. Yellow is always a surface behind navy text, never text itself.
 */

@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 300; font-display: swap; src: url("fonts/fira-sans-latin-300-normal.woff2") format("woff2"); unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 300; font-display: swap; src: url("fonts/fira-sans-latin-ext-300-normal.woff2") format("woff2"); unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1E00-1E9F, U+1EF2-1EFF, U+20A0-20AB, U+20AD-20C0, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/fira-sans-latin-400-normal.woff2") format("woff2"); unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/fira-sans-latin-ext-400-normal.woff2") format("woff2"); unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1E00-1E9F, U+1EF2-1EFF, U+20A0-20AB, U+20AD-20C0, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 700; font-display: swap; src: url("fonts/fira-sans-latin-700-normal.woff2") format("woff2"); unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Fira Sans"; font-style: normal; font-weight: 700; font-display: swap; src: url("fonts/fira-sans-latin-ext-700-normal.woff2") format("woff2"); unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1E00-1E9F, U+1EF2-1EFF, U+20A0-20AB, U+20AD-20C0, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Lato"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/lato-latin-400-normal.woff2") format("woff2"); unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Lato"; font-style: normal; font-weight: 400; font-display: swap; src: url("fonts/lato-latin-ext-400-normal.woff2") format("woff2"); unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1E00-1E9F, U+1EF2-1EFF, U+20A0-20AB, U+20AD-20C0, U+2C60-2C7F, U+A720-A7FF; }
@font-face { font-family: "Lato"; font-style: normal; font-weight: 700; font-display: swap; src: url("fonts/lato-latin-700-normal.woff2") format("woff2"); unicode-range: U+0000-00FF, U+0131, U+0152-0153, U+02BB-02BC, U+02C6, U+02DA, U+02DC, U+2000-206F, U+20AC, U+2122, U+2191, U+2193, U+2212, U+2215, U+FEFF, U+FFFD; }
@font-face { font-family: "Lato"; font-style: normal; font-weight: 700; font-display: swap; src: url("fonts/lato-latin-ext-700-normal.woff2") format("woff2"); unicode-range: U+0100-02BA, U+02BD-02C5, U+02C7-02CC, U+02CE-02D7, U+02DD-02FF, U+1E00-1E9F, U+1EF2-1EFF, U+20A0-20AB, U+20AD-20C0, U+2C60-2C7F, U+A720-A7FF; }

:root {
    --brand-yellow: #FFFF00;
    --text: #000129;
    --text-strong: #030303;
    --button-text: #222222;
    --bg: #F9F9F9;
    --bg-alt: #E6E6E6;
    --surface: #FFFFFF;
    --grey-1: #CFCFCF;
    --grey-0: #F1F1F1;
    --line: #D8D8D8;
    --muted: #4D4E63;          /* derived: secondary text, 7.7:1 on #F9F9F9 */
    --footer-bg: #222222;
    --footer-text: #999999;
    --link-hover: #0067DA;
    --shadow: 0 15px 60px rgba(0, 0, 0, 0.1);
    --shadow-soft: 0 10px 40px rgba(0, 0, 0, 0.06);
    --font: "Fira Sans", "Helvetica Neue", Arial, sans-serif;
    --font-heading: "Lato", "Helvetica Neue", Arial, sans-serif;
    --wrap: 1140px;
    --gutter: clamp(1.25rem, 4vw, 2.5rem);
    --tilt: 70px;
    color-scheme: light;
}

/* ------------------------------------------------------------------ base */
html { background: var(--bg); }
body {
    background: var(--bg);
    color: var(--text);
    font-family: var(--font);
    font-size: 1rem;
    font-weight: 300;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}
a { color: var(--text); text-underline-offset: 0.2em; }
a:hover { color: var(--link-hover); }
:focus-visible { outline: 2px solid var(--text); outline-offset: 3px; }
::selection { background: var(--brand-yellow); color: var(--text); }
.bk-wrap { width: 100%; max-width: calc(var(--wrap) + 2 * var(--gutter)); margin-inline: auto; padding-inline: var(--gutter); }
.bk-skip { background: var(--text); color: #fff; padding: 0.75rem 1.25rem; font-weight: 400; }

/* ------------------------------------------------------------------ header: yellow band */
.bk-header { background: var(--brand-yellow); }
.bk-header__inner {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem 2rem;
    max-width: calc(1240px + 2 * var(--gutter));
    padding-block: 1rem;
}
.bk-header__brand {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    font-size: clamp(1.25rem, 2.6vw, 1.8rem);
    font-weight: 300;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    text-decoration: none;
    color: var(--text);
}
.bk-header__logo { display: none; }
.bk-header__tools { display: flex; align-items: center; gap: 1.5rem; }
.bk-header__link {
    display: inline-flex;
    align-items: center;
    min-height: 44px;
    font-size: 0.875rem;
    font-weight: 400;
    text-decoration: none;
}
.bk-header__link:hover { color: var(--text); text-decoration: underline; }

/* ------------------------------------------------------------------ hero with slanted edge */
.bk-hero {
    position: relative;
    background: var(--bg-alt);
    clip-path: polygon(0 0, 100% 0, 100% calc(100% - var(--tilt)), 0 100%);
    padding-bottom: calc(var(--tilt) + 1rem);
}
.bk-hero__inner {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    padding-block: clamp(3rem, 8vw, 6rem) 2rem;
}
.bk-hero__text { max-width: 44rem; }
.bk-hero__media:empty { display: none; }
.bk-hero__image { width: 100%; aspect-ratio: 16 / 9; object-fit: cover; }
.bk-hero__kicker,
.bk-event__kicker {
    font-size: 13px;
    font-weight: 400;
    letter-spacing: 2px;
    text-transform: uppercase;
    color: #000;
}
.bk-hero__title,
.bk-event__title {
    margin: 10px 0 30px;
    font-size: 40px;
    font-weight: 400;
    line-height: 1.2;
    color: var(--text-strong);
}
.bk-hero__lead { max-width: 40rem; font-size: 1.125rem; font-weight: 300; }

/* ------------------------------------------------------------------ sections */
.bk-section__inner { padding-block: clamp(3rem, 7vw, 5rem); }
.bk-section__head { margin-bottom: 2.5rem; text-align: center; }
.bk-section__num,
.bk-step__num { display: none; }
.bk-section__title {
    font-family: var(--font-heading);
    font-size: 30px;
    font-weight: 700;
    line-height: 1.3;
    color: var(--text);
}
.bk-section--hosts[data-count="1"] { display: none; }

/* session tiles: square image + overlapping white label */
.bk-sessions {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 15rem), 1fr));
    gap: 3rem 1.5rem;
}
.bk-session { display: flex; flex-direction: column; text-align: center; }
.bk-session__num { display: none; }
.bk-session__media {
    aspect-ratio: 1;
    overflow: hidden;
    background: var(--brand-yellow);
    transition: transform 0.3s ease;
}
.bk-session:hover .bk-session__media,
.bk-session:focus-within .bk-session__media { transform: translateY(-8px); }
.bk-session__image { width: 100%; height: 100%; object-fit: cover; }
.bk-session__placeholder {
    display: grid;
    place-items: center;
    height: 100%;
    font-size: clamp(3rem, 8vw, 4.5rem);
    font-weight: 300;
    color: var(--text);
}
.bk-session__body { display: flex; flex-direction: column; align-items: center; flex: 1; }
.bk-session__title {
    position: relative;
    z-index: 1;
    margin-top: -25px;
    padding: 0.85rem 1.25rem;
    border-style: solid;
    border-width: 5px 5px 2px 5px;
    border-color: #fff;
    background: #fff;
    box-shadow: var(--shadow);
    font-family: var(--font);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 2px;
    line-height: 1.4;
    text-transform: uppercase;
    color: var(--button-text);
}
.bk-session__link { color: inherit; text-decoration: none; }
.bk-session:hover .bk-session__link { color: var(--text); }
.bk-session__meta {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0 0.75rem;
    margin-top: 1.25rem;
    font-size: 0.875rem;
    font-weight: 400;
    color: var(--muted);
}
.bk-sessions[data-multi-host="0"] .bk-session__hosts { display: none; }
.bk-session__desc { margin-top: 0.5rem; max-width: 30ch; }
.bk-session__note {
    margin-top: 0.75rem;
    padding: 0.1rem 0.6rem;
    background: var(--brand-yellow);
    font-size: 0.8125rem;
    font-weight: 400;
}
.bk-session__action { display: none; }

/* hosts */
.bk-hosts { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 18rem), 1fr)); gap: 2rem; }
.bk-host { text-align: center; }
.bk-host__portrait { width: 10rem; margin: 0 auto 1rem; aspect-ratio: 1; overflow: hidden; background: var(--brand-yellow); }
.bk-host__image { width: 100%; height: 100%; object-fit: cover; }
.bk-host__monogram { display: grid; place-items: center; height: 100%; font-size: 2.5rem; }
.bk-host__name { font-family: var(--font-heading); font-weight: 700; }

/* ------------------------------------------------------------------ booking */
.bk-booking__inner { padding-block: clamp(2.5rem, 6vw, 4.5rem) 0; }
.bk-event { max-width: 48rem; margin-bottom: 2.5rem; }
.bk-event__facts { display: flex; flex-wrap: wrap; gap: 0.5rem 2rem; }
.bk-event__fact { display: flex; gap: 0.5rem; align-items: baseline; }
.bk-event__key { font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 400; }
.bk-event__value { font-weight: 400; }
.bk-event__desc { margin-top: 1rem; font-size: 1.125rem; }
.bk-event__current { margin-top: 1.5rem; padding: 1rem 1.25rem; background: #fff; box-shadow: var(--shadow-soft); }
.bk-event__current-label { font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 400; }

.bk-form {
    display: grid;
    grid-template-columns: minmax(0, 1fr);
    gap: 1.5rem;
}
@media (width >= 1025px) {
    .bk-form { grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr); }
    .bk-alert, .bk-step--details, .bk-step--confirm { grid-column: 1 / -1; }
}
.bk-alert { padding: 1.25rem 1.5rem; background: #fff; border-left: 6px solid var(--text); box-shadow: var(--shadow-soft); }
.bk-alert__title { font-weight: 700; }
.bk-alert__list { margin-top: 0.25rem; }
.bk-step { padding: clamp(1.25rem, 3vw, 2rem); background: var(--surface); box-shadow: var(--shadow-soft); }
.bk-step:focus { outline: none; }
.bk-step__head { margin-bottom: 1.25rem; }
.bk-step__title { font-family: var(--font-heading); font-size: 1.375rem; font-weight: 700; color: var(--text); }

.bk-tz { display: flex; flex-wrap: wrap; align-items: center; gap: 0.5rem 1rem; margin-bottom: 1.25rem; }
.bk-tz__label { font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 400; }
.bk-tz__select { min-height: 44px; max-width: 100%; padding: 0 0.75rem; border: 1px solid #767676; border-radius: 0; background: #fff; font-weight: 400; }

.bk-calendar__head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 0.75rem; }
.bk-calendar__month { font-family: var(--font-heading); font-size: 1.125rem; font-weight: 700; }
.bk-calendar__nav { border: 1px solid var(--line); border-radius: 0; background: #fff; font-size: 1.5rem; line-height: 1; color: var(--text); }
.bk-calendar__nav:hover:not(:disabled) { background: var(--brand-yellow); }
.bk-calendar__nav:disabled { color: #767676; background: var(--grey-0); cursor: default; }
.bk-calendar__grid { width: 100%; table-layout: fixed; border-spacing: 4px; border-collapse: separate; }
.bk-calendar__weekday { padding-bottom: 0.25rem; font-size: 12px; font-weight: 400; letter-spacing: 1.5px; text-transform: uppercase; }
.bk-calendar__weekday abbr { text-decoration: none; }
.bk-calendar__days td { padding: 0; }
.bk-day {
    width: 100%;
    aspect-ratio: 1;
    border: 1px solid var(--line);
    border-radius: 0;
    background: #fff;
    font-size: 0.9375rem;
    font-weight: 400;
    color: var(--text);
    transition: box-shadow 0.2s;
}
.bk-day:hover:not([aria-disabled="true"]) { box-shadow: var(--shadow); border-color: var(--text); }
.bk-day[aria-disabled="true"] { border-color: transparent; background: var(--grey-0); color: #666; }
.bk-day[aria-current="date"] { box-shadow: inset 0 -4px 0 var(--brand-yellow); }
[aria-selected="true"] > .bk-day { background: var(--text); border-color: var(--text); color: #fff; box-shadow: none; }

.bk-state { display: flex; flex-wrap: wrap; align-items: center; gap: 1rem; padding-block: 1rem; font-weight: 400; }
.bk-state__spinner { width: 1.25rem; height: 1.25rem; border: 2px solid var(--line); border-top-color: var(--text); border-radius: 50%; animation: bk-spin 0.9s linear infinite; }
@keyframes bk-spin { to { transform: rotate(360deg); } }

.bk-slots__hint { color: var(--muted); }
.bk-slots__title { margin-bottom: 1rem; font-family: var(--font-heading); font-size: 1rem; font-weight: 700; }
.bk-slots { display: grid; grid-template-columns: repeat(auto-fill, minmax(6rem, 1fr)); gap: 0.75rem; }
.bk-slot {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid var(--line);
    border-radius: 0;
    background: #fff;
    font-size: 0.9375rem;
    font-weight: 700;
    letter-spacing: 1px;
    color: var(--button-text);
    transition: box-shadow 0.2s;
}
.bk-slot:hover { box-shadow: var(--shadow); border-color: var(--text); }
.bk-slot[aria-pressed="true"] { background: var(--text); border-color: var(--text); color: #fff; }

.bk-selection { margin-bottom: 1.25rem; padding: 0.75rem 1rem; background: var(--brand-yellow); }
.bk-selection__label { display: block; font-size: 12px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 400; }
.bk-selection__value { font-weight: 400; }

.bk-step--details .bk-step__body { display: grid; grid-template-columns: repeat(auto-fit, minmax(min(100%, 20rem), 1fr)); gap: 1.25rem 1.5rem; }
.bk-step--details .bk-selection,
.bk-field--notes { grid-column: 1 / -1; }
.bk-field__label { display: block; margin-bottom: 0.35rem; font-size: 13px; font-weight: 400; letter-spacing: 1.5px; text-transform: uppercase; }
.bk-field__input {
    display: block;
    width: 100%;
    min-height: 44px;
    padding: 0.7rem 0.9rem;
    border: 1px solid #767676;
    border-radius: 0;
    background: #fff;
    font-size: 1rem;
    font-weight: 400;
}
textarea.bk-field__input { min-height: 7rem; resize: vertical; }
.bk-field__input:focus-visible { outline: 2px solid var(--text); outline-offset: 1px; border-color: var(--text); }
.bk-field--invalid .bk-field__input { border: 2px solid var(--text); }
.bk-field__hint { margin-top: 0.35rem; font-size: 0.875rem; color: var(--muted); }
.bk-field__error { margin-top: 0.35rem; padding-left: 0.6rem; border-left: 4px solid var(--text); font-size: 0.9375rem; font-weight: 700; }
.bk-privacy { margin-bottom: 1.25rem; font-size: 0.9375rem; font-weight: 400; }

/* ------------------------------------------------------------------ buttons */
.bk-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.9rem 2rem;
    border-radius: 0;
    font-family: var(--font);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 2px;
    text-transform: uppercase;
    text-decoration: none;
    cursor: pointer;
    transition: box-shadow 0.2s, background-color 0.2s;
}
.bk-button--primary,
.bk-button--danger { border: 0; background: var(--text); color: #fff; box-shadow: var(--shadow); }
.bk-button--primary:hover,
.bk-button--danger:hover { background: #1A1A1A; color: #fff; }
.bk-button--secondary {
    border-style: solid;
    border-width: 5px 5px 2px 5px;
    border-color: #fff;
    background: #fff;
    color: var(--button-text);
    box-shadow: var(--shadow);
}
.bk-button--secondary:hover { color: var(--text); background: var(--brand-yellow); border-color: var(--brand-yellow); }
.bk-submit { width: 100%; }
@media (width >= 768px) { .bk-submit { width: auto; min-width: 18rem; } }
.bk-button[aria-disabled="true"] { opacity: 0.7; cursor: progress; }

/* ------------------------------------------------------------------ results: yellow band with slanted top */
.bk-result__band { background: var(--bg-alt); }
.bk-result--success .bk-result__band {
    background: var(--brand-yellow);
    clip-path: polygon(0 var(--tilt), 100% 0, 100% 100%, 0 100%);
    margin-top: 1rem;
}
.bk-result__band-inner { padding-block: calc(var(--tilt) + 2.5rem) 3rem; }
.bk-result--success .bk-result__band-inner { text-align: center; }
.bk-result__title { font-size: 40px; font-weight: 400; line-height: 1.2; color: var(--text-strong); }
.bk-result__lead { margin-top: 1rem; font-size: 1.125rem; }
.bk-result__body { max-width: calc(48rem + 2 * var(--gutter)); padding-block: 3rem 0; }
.bk-summary { padding: clamp(1.25rem, 3vw, 2rem); background: #fff; box-shadow: var(--shadow-soft); }
.bk-summary__row { display: grid; grid-template-columns: 8rem minmax(0, 1fr); gap: 1rem; padding-block: 0.6rem; border-bottom: 1px solid var(--line); }
.bk-summary__row:last-child { border-bottom: 0; }
.bk-summary__key { font-size: 13px; letter-spacing: 1.5px; text-transform: uppercase; font-weight: 400; padding-top: 0.15rem; }
.bk-summary__value { display: flex; flex-direction: column; font-weight: 400; }
.bk-summary__tz { color: var(--muted); font-size: 0.875rem; }
.bk-summary--cancelled .bk-summary__value { color: var(--muted); }
.bk-result__hint { margin-top: 1.5rem; }
.bk-result__actions { display: flex; flex-wrap: wrap; gap: 1rem; margin-top: 2rem; }
.bk-confirm__question { margin-top: 2rem; font-family: var(--font-heading); font-size: 1.375rem; font-weight: 700; }

/* ------------------------------------------------------------------ footer */
.bk-footer { margin-top: clamp(3rem, 8vw, 6rem); background: var(--footer-bg); color: var(--footer-text); }
.bk-footer__inner { display: flex; flex-wrap: wrap; justify-content: space-between; align-items: center; gap: 0.5rem 2rem; padding-block: 1.5rem; font-size: 13px; }
.bk-footer__legal { display: flex; gap: 1.5rem; }
.bk-footer__legal a { display: inline-flex; align-items: center; min-height: 44px; color: #fff; text-decoration: none; }
.bk-footer__legal a:hover { color: #fff; text-decoration: underline; }
.bk-footer a:focus-visible { outline-color: #fff; }

/* ------------------------------------------------------------------ responsive */
@media (width <= 1024px) {
    :root { --tilt: 50px; }
    .bk-hero__title, .bk-event__title, .bk-result__title { font-size: 32px; }
}
@media (width <= 767px) {
    :root { --tilt: 40px; }
    .bk-hero__title, .bk-event__title, .bk-result__title { font-size: 24px; }
    .bk-section__title { font-size: 24px; }
    .bk-summary__row { grid-template-columns: minmax(0, 1fr); gap: 0; }
    .bk-step { padding: 1.25rem 0.75rem; }
    .bk-calendar__grid { border-spacing: 2px; }
}