/* ============================================================
   Kua Number Calculator — Styles
   Closely matching Lo Shu Grid Calculator design
   Font: Inter/system-ui  |  Purple theme matching LoShu
   ============================================================ */

:root {
    /* Purple palette matching Lo Shu Grid */
    --kua-purple-dark:   #2D1B69;
    --kua-purple-mid:    #4A2C8F;
    --kua-purple-main:   #5B35A8;
    --kua-purple-light:  #7B5BC4;
    --kua-purple-pale:   #F0EBF8;
    --kua-purple-border: #D4C5E8;
    --kua-gold:          #C9A84C;
    --kua-gold-bg:       #FFF8E6;
    --kua-teal:          #2A9D8F;
    --kua-teal-bg:       #E8F8F6;
    --kua-white:         #FFFFFF;
    --kua-bg:            #F8F6FC;
    --kua-text:          #1A1033;
    --kua-text-mid:      #6B5E8A;
    --kua-text-light:    #9B8EB8;
    --kua-border:        #E8E2F5;
    --kua-error:         #DC2626;
    --kua-green:         #25D366;
    --kua-radius:        16px;
    --kua-radius-sm:     10px;
    --kua-shadow:        0 4px 32px rgba(45,27,105,0.13);
    --kua-font:          'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
}

/* ── Wrapper ── */
.kua-calc-wrap {
    max-width: 680px;
    margin: 0 auto 48px;
    font-family: var(--kua-font);
    color: var(--kua-text);
    border-radius: var(--kua-radius);
    overflow: hidden;
    box-shadow: var(--kua-shadow);
    background: var(--kua-white);
    border: 1px solid var(--kua-border);
}

/* ══════════════════════════════════════════
   HERO HEADER — deep purple gradient
   ══════════════════════════════════════════ */
.kua-calc__hero {
    background: linear-gradient(160deg, #2D1B69 0%, #4A2C8F 50%, #1A0A3A 100%);
    padding: 36px 40px 32px;
    text-align: center;
    position: relative;
    overflow: hidden;
}
.kua-calc__hero::before {
    content: '';
    position: absolute; inset: 0;
    background: radial-gradient(ellipse at 70% 20%, rgba(255,255,255,0.06) 0%, transparent 60%);
    pointer-events: none;
}
.kua-calc__hero-icon {
    display: block;
    font-size: 2.2rem;
    margin-bottom: 12px;
    position: relative;
}
.kua-calc__title {
    font-size: 1.65rem;
    font-weight: 800;
    color: var(--kua-white);
    margin: 0 0 10px;
    line-height: 1.25;
    position: relative;
}
.kua-calc__subtitle {
    font-size: 0.92rem;
    color: rgba(255,255,255,0.72);
    margin: 0 auto;
    line-height: 1.65;
    max-width: 500px;
    position: relative;
}

/* ══════════════════════════════════════════
   FORM
   ══════════════════════════════════════════ */
.kua-form {
    padding: 28px 40px 24px;
    background: var(--kua-white);
}

.kua-form__field {
    margin-bottom: 18px;
}
.kua-form__field label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--kua-text);
    margin-bottom: 6px;
}
.kua-form__required { color: var(--kua-error); margin-left: 2px; }
.kua-form__optional {
    font-weight: 400;
    color: var(--kua-text-light);
    font-size: 0.8rem;
}

/* Inputs */
.kua-form input[type="text"],
.kua-form input[type="email"],
.kua-form input[type="date"],
.kua-form select {
    width: 100%;
    padding: 12px 14px;
    border: 1.5px solid var(--kua-purple-border);
    border-radius: var(--kua-radius-sm);
    background: var(--kua-white);
    font-size: 0.95rem;
    color: var(--kua-text);
    font-family: var(--kua-font);
    transition: border-color .18s, box-shadow .18s;
    box-sizing: border-box;
    -webkit-appearance: none;
    appearance: none;
}
.kua-form select {
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='8'%3E%3Cpath fill='%236B5E8A' d='M0 0l7 8 7-8z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 13px center;
    padding-right: 36px;
    cursor: pointer;
}
.kua-form input:focus,
.kua-form select:focus {
    outline: none;
    border-color: var(--kua-purple-main);
    box-shadow: 0 0 0 3px rgba(91,53,168,0.14);
}
.kua-form input::placeholder { color: #BDB0D4; }

/* 2-col row */
.kua-form__row-2 {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px;
    margin-bottom: 18px;
}
.kua-form__row-2 .kua-form__field { margin-bottom: 0; }

/* Gender locked badge */
.kua-gender-locked-note {
    display: inline-flex; align-items: center; gap: 6px;
    background: var(--kua-purple-pale);
    border: 1px solid var(--kua-purple-border);
    color: var(--kua-purple-mid);
    font-size: 0.82rem; font-weight: 600;
    padding: 8px 14px; border-radius: 50px;
    margin-bottom: 18px;
}

/* ══════════════════════════════════════════
   SUBMIT BUTTON
   ══════════════════════════════════════════ */
.kua-btn--calculate {
    width: 100%;
    padding: 15px 24px;
    background: linear-gradient(135deg, var(--kua-purple-dark) 0%, var(--kua-purple-mid) 100%);
    color: var(--kua-white);
    border: none;
    border-radius: var(--kua-radius-sm);
    font-size: 1rem;
    font-weight: 700;
    font-family: var(--kua-font);
    cursor: pointer;
    letter-spacing: 0.01em;
    transition: opacity .2s, transform .1s;
    display: flex; align-items: center; justify-content: center; gap: 8px;
    margin-bottom: 10px;
}
.kua-btn--calculate:hover  { opacity: .88; }
.kua-btn--calculate:active { transform: scale(.985); }
.kua-btn-icon { font-size: 1.05rem; }

.kua-form__privacy {
    text-align: center;
    font-size: 0.78rem;
    color: var(--kua-text-light);
    margin: 0;
    font-family: var(--kua-font);
}

/* ══════════════════════════════════════════
   FORMULA EXPLAINER
   ══════════════════════════════════════════ */
.kua-formula-explainer {
    background: var(--kua-purple-pale);
    border-left: 3px solid var(--kua-purple-main);
    border-radius: 0 var(--kua-radius-sm) var(--kua-radius-sm) 0;
    padding: 14px 18px; margin-bottom: 20px;
    display: flex; flex-direction: column; gap: 8px;
}
.kua-formula-step { display: flex; align-items: flex-start; gap: 11px; font-size: 0.9rem; }
.kua-formula-step__num {
    background: var(--kua-purple-main); color: var(--kua-white);
    font-weight: 700; font-size: 0.75rem;
    width: 20px; height: 20px; border-radius: 50%;
    display: flex; align-items: center; justify-content: center;
    flex-shrink: 0; margin-top: 2px;
}

/* After-2000 comparison */
.kua-formula-comparison {
    display: grid; grid-template-columns: 1fr auto 1fr;
    border: 1.5px solid var(--kua-purple-border);
    border-radius: var(--kua-radius-sm); overflow: hidden; margin-bottom: 20px;
}
.kua-formula-col { padding: 13px 15px; background: var(--kua-white); }
.kua-formula-col h4 { margin: 0 0 6px; color: var(--kua-text-mid); font-size: 0.82rem; font-family: var(--kua-font); }
.kua-formula-col p  { margin: 4px 0; font-size: 0.85rem; }
.kua-formula-col code { background: var(--kua-purple-pale); padding: 2px 6px; border-radius: 4px; font-size: 0.82rem; }
.kua-formula-col--active { background: var(--kua-purple-dark); color: var(--kua-white); }
.kua-formula-col--active h4 { color: var(--kua-gold); }
.kua-formula-col--active code { background: rgba(255,255,255,.15); color: var(--kua-white); }
.kua-formula-divider {
    padding: 13px 10px; background: var(--kua-purple-border);
    display: flex; align-items: center;
    font-weight: 700; font-size: .82rem; color: var(--kua-text-mid);
}

/* ══════════════════════════════════════════
   COMPASS PICKER
   ══════════════════════════════════════════ */
.kua-compass-picker {
    display: grid; grid-template-columns: repeat(4,1fr); gap: 7px; margin-bottom: 16px;
}
.kua-compass-picker__btn {
    display: flex; flex-direction: column; align-items: center;
    padding: 9px 5px;
    border: 1.5px solid var(--kua-purple-border);
    border-radius: var(--kua-radius-sm);
    background: var(--kua-white); cursor: pointer; transition: all .18s; gap: 2px;
    font-family: var(--kua-font);
}
.kua-compass-picker__btn:hover { border-color: var(--kua-purple-main); background: var(--kua-purple-pale); }
.kua-compass-picker__btn.active { background: var(--kua-purple-dark); border-color: var(--kua-purple-dark); color: var(--kua-white); }
.kua-compass-picker__code  { font-size: .95rem; font-weight: 700; }
.kua-compass-picker__label { font-size: .68rem; opacity: .8; }

/* ══════════════════════════════════════════
   COUPLES FORM
   ══════════════════════════════════════════ */
.kua-couples-form-row { display: flex; gap: 16px; margin-bottom: 18px; }
.kua-couples-person {
    flex: 1; background: var(--kua-bg);
    border: 1.5px solid var(--kua-border); border-radius: var(--kua-radius-sm); padding: 16px;
}
.kua-couples-person__title {
    font-size: 0.8rem; font-weight: 700; color: var(--kua-purple-mid); margin: 0 0 12px;
    text-transform: uppercase; letter-spacing: 0.06em;
    border-bottom: 1px solid var(--kua-border); padding-bottom: 9px; font-family: var(--kua-font);
}

/* ══════════════════════════════════════════
   SPINNER
   ══════════════════════════════════════════ */
.kua-spinner {
    text-align: center; padding: 48px 40px;
    color: var(--kua-text-mid); font-family: var(--kua-font);
    font-size: 0.9rem;
}
.kua-spinner__ring {
    display: inline-block; width: 40px; height: 40px;
    border: 3px solid var(--kua-border);
    border-top-color: var(--kua-purple-main);
    border-radius: 50%; animation: kua-spin .7s linear infinite;
    margin-bottom: 12px; display: block; margin: 0 auto 12px;
}
@keyframes kua-spin { to { transform: rotate(360deg); } }

/* ══════════════════════════════════════════
   ERROR
   ══════════════════════════════════════════ */
.kua-error-msg {
    background: #fef2f2; border: 1px solid #fca5a5; color: var(--kua-error);
    padding: 12px 16px; border-radius: var(--kua-radius-sm);
    font-size: .88rem; font-family: var(--kua-font);
    margin: 0 40px 14px;
}

/* ══════════════════════════════════════════
   SOLAR BUFFER MODAL
   ══════════════════════════════════════════ */
.kua-modal { display: none; position: fixed; inset: 0; z-index: 9999; align-items: center; justify-content: center; }
.kua-modal--open { display: flex; }
.kua-modal__overlay { position: absolute; inset: 0; background: rgba(10,5,30,.7); backdrop-filter: blur(3px); }
.kua-modal__box {
    position: relative; background: var(--kua-white); border-radius: 16px; padding: 32px 28px;
    max-width: 440px; width: 90%; box-shadow: 0 24px 64px rgba(0,0,0,.3); z-index: 1;
    font-family: var(--kua-font);
}
.kua-modal__icon     { font-size: 2rem; margin-bottom: 10px; }
.kua-modal__title    { font-size: 1.1rem; font-weight: 700; color: var(--kua-purple-dark); margin: 0 0 10px; }
.kua-modal__body,
.kua-modal__question { font-size: .88rem; color: var(--kua-text-mid); line-height: 1.6; margin-bottom: 10px; }
.kua-modal__lichun-date {
    background: var(--kua-purple-pale); border: 1px solid var(--kua-purple-border);
    color: var(--kua-purple-mid); padding: 7px 13px;
    border-radius: 7px; font-size: .85rem; margin-bottom: 12px;
}
.kua-modal__actions { display: flex; gap: 10px; margin-bottom: 14px; }
.kua-modal__why { font-size: .79rem; color: var(--kua-text-light); border-top: 1px solid var(--kua-border); padding-top: 10px; }
.kua-modal__why summary { cursor: pointer; color: var(--kua-purple-main); font-weight: 600; }
.kua-modal__why p { margin: 7px 0 0; line-height: 1.5; }

.kua-btn {
    display: inline-flex; align-items: center; justify-content: center;
    gap: 6px; padding: 10px 20px; border-radius: var(--kua-radius-sm);
    font-size: .88rem; font-weight: 600; cursor: pointer; border: none;
    transition: all .18s; font-family: var(--kua-font);
}
.kua-btn--primary  { background: var(--kua-purple-dark); color: var(--kua-white); }
.kua-btn--primary:hover { background: var(--kua-purple-mid); }
.kua-btn--secondary { background: var(--kua-bg); color: var(--kua-text); border: 1.5px solid var(--kua-border); }
.kua-btn--secondary:hover { background: var(--kua-border); }

/* ══════════════════════════════════════════
   RESPONSIVE
   ══════════════════════════════════════════ */
@media (max-width: 600px) {
    .kua-calc__hero       { padding: 26px 20px 22px; }
    .kua-calc__title      { font-size: 1.35rem; }
    .kua-form             { padding: 20px 18px; }
    .kua-form__row-2      { grid-template-columns: 1fr; gap: 0; }
    .kua-error-msg        { margin: 0 18px 14px; }
    .kua-couples-form-row { flex-direction: column; }
    .kua-formula-comparison { grid-template-columns: 1fr; }
}