/* --- Стили для Квадратных уравнений (Math Theme) --- */
:root {
    --accent-indigo: #4F46E5; /* Indigo 600 */
    --accent-indigo-light: #EEF2FF; /* Indigo 50 */
    --gradient-indigo-card: linear-gradient(135deg, #6366F1 0%, #4338CA 100%);
}

.calc-header { margin-bottom: 32px; }
.subtitle { color: var(--text-secondary); margin-top: 8px; }

/* Сетка */
.calc-grid { display: grid; grid-template-columns: 1fr; gap: 24px; align-items: start; }
@media (min-width: 900px) { .calc-grid { grid-template-columns: 1.2fr 0.8fr; } }

/* Inputs */
.calc-inputs { gap: 24px; }
.input-group { margin-bottom: 24px; }
.input-group label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 8px; color: var(--text-primary); }

/* Живое уравнение */
.equation-display {
    background: #F3F4F6; border-radius: 16px; padding: 24px;
    text-align: center; font-size: 28px; font-weight: 700; font-family: 'Times New Roman', serif;
    margin-bottom: 24px; color: var(--text-primary);
    border: 1px dashed #D1D5DB;
}
.equation-display span { color: var(--accent-indigo); }

/* ABC Grid */
.abc-grid { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 12px; }

.input-wrapper { 
    position: relative; display: flex; align-items: center; 
    background: #fff; border: 1px solid #E5E7EB; border-radius: 12px;
    padding-left: 12px; transition: border 0.2s;
    overflow: hidden; /* Защита от вылезания контента */
}
.input-wrapper:focus-within { border-color: var(--accent-indigo); box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15); }

.abc-label {
    font-family: 'Times New Roman', serif; font-style: italic; font-weight: 700;
    font-size: 18px; color: var(--text-secondary); margin-right: 4px;
    /* --- ИСПРАВЛЕНИЕ: Запрещаем перенос --- */
    white-space: nowrap; 
    flex-shrink: 0;
}

.input-wrapper input {
    width: 100%; padding: 14px 12px 14px 4px; 
    font-size: 18px; font-weight: 600;
    border: none; outline: none; background: transparent;
    font-family: var(--font-main);
    /* Убираем лишние отступы чтобы влезло */
    min-width: 0; 
}

/* FIX стрелок input type=number */
input[type="number"]::-webkit-outer-spin-button,
input[type="number"]::-webkit-inner-spin-button { -webkit-appearance: none; margin: 0; }
input[type="number"] { -moz-appearance: textfield; }

.helper-text { font-size: 12px; color: var(--text-secondary); margin-top: 8px; }

/* Результаты (Indigo Card) */
.card--indigo { background: var(--gradient-indigo-card); color: #fff; border: none; }
.card--indigo h2 { color: rgba(255,255,255,0.9); margin-bottom: 20px; font-size: 16px; }
@media (min-width: 900px) { .sticky-card { position: sticky; top: 24px; } }

.math-font { font-family: 'Times New Roman', serif; font-style: italic; }

.big-result {
    font-size: 32px; font-weight: 700; line-height: 1.2; margin-bottom: 24px;
}

.summary-divider { height: 1px; background: rgba(255,255,255,0.2); margin: 24px 0; }

/* Шаги решения */
.solution-steps h3 { font-size: 14px; text-transform: uppercase; opacity: 0.8; margin-bottom: 16px; letter-spacing: 0.05em; }

.step-box {
    background: rgba(255,255,255,0.1); border-radius: 12px; padding: 16px; margin-bottom: 12px;
}
.step-title {
    display: block; font-size: 13px; font-weight: 700; margin-bottom: 8px; opacity: 0.9;
}
.math-row {
    font-family: 'Courier New', monospace; font-size: 14px; margin-bottom: 4px;
}
.result-row { font-weight: 700; color: #fff; margin-top: 8px; font-size: 16px; }


/* --- НОВЫЕ ИНФОРМАЦИОННЫЕ БЛОКИ --- */

.info-wrapper {
    padding: 60px 0 60px 0;
    margin-top: 60px;
    border-top: 1px solid rgba(0,0,0,0.06);
    margin-bottom: 20px;
}

/* Центрирование контента */
.formulas-section,
.calc-description,
.faq-section {
    max-width: 800px;
    width: 100%;
    margin-left: auto;
    margin-right: auto;
}

/* Заголовки с иконками */
.icon-heading {
    display: flex;
    align-items: flex-start;
    gap: 16px;
    margin-bottom: 24px;
    font-size: 24px;
    font-weight: 800;
    color: var(--text-primary);
    line-height: 1.3;
}

.header-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 48px;
    height: 48px;
    border-radius: 14px;
    background: #fff;
    box-shadow: 0 4px 12px rgba(0,0,0,0.04);
    flex-shrink: 0;
    margin-top: -4px;
}

.header-icon svg { width: 24px; height: 24px; stroke-width: 2px; }

/* Цвета иконок */
.blue-icon svg { color: #2563EB; }
.orange-icon svg { color: #F59E0B; }
.green-icon svg { color: #10B981; }
.red-icon svg { color: #E11D48; }

/* Маленькие подзаголовки */
.small-heading {
    margin-top: 40px;
    margin-bottom: 16px;
    font-size: 20px;
}
.small-heading .header-icon { width: 40px; height: 40px; }
.small-heading .header-icon svg { width: 20px; height: 20px; }

.intro-text {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 32px;
    line-height: 1.6;
}

/* --- Секция Формул --- */
.formulas-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 48px;
}

.formula-card {
    background: #fff;
    border: 1px solid rgba(0,0,0,0.04);
    box-shadow: var(--shadow-soft);
    border-radius: var(--radius-lg); 
    padding: 24px;
    transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
    display: flex;
    flex-direction: column;
}
.formula-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); }

/* Вертикальный хедер (бейдж сверху) */
.formula-header {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
    margin-bottom: 16px;
}

.formula-card h3 {
    margin: 0;
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1.3;
}

/* Бейджи */
.badge-blue {
    background: #2563EB; color: #fff;
    padding: 6px 12px; border-radius: 99px;
    font-size: 11px; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.05em;
    display: inline-block;
}
.badge-green {
    background: #10B981; color: #fff;
    padding: 6px 12px; border-radius: 99px;
    font-size: 11px; font-weight: 700;
    text-transform: uppercase; letter-spacing: 0.05em;
    display: inline-block;
}

.formula-card p {
    font-size: 14px; color: var(--text-secondary);
    margin: 0; line-height: 1.5; font-weight: 500;
}

.math-expression {
    background: #F9FAFB;
    border: 1px solid #E5E7EB;
    padding: 12px 16px;
    border-radius: 12px;
    font-weight: 700;
    color: var(--accent-indigo);
    text-align: center;
    margin-bottom: 16px;
    font-size: 15px;
}

/* Разделитель */
.soft-divider {
    border: none; height: 1px;
    background: linear-gradient(90deg, transparent, #E5E7EB, transparent);
    margin: 48px auto;
    max-width: 800px;
    width: 100%;
}

/* Описание */
.calc-description p {
    font-size: 16px; line-height: 1.7;
    color: var(--text-secondary); margin-bottom: 24px;
}
.calc-description strong { color: var(--text-primary); }

/* FAQ */
.faq-section .faq-item {
    background: #fff; border: 1px solid #E5E7EB;
    border-radius: 12px; margin-bottom: 12px;
    overflow: hidden; transition: all 0.2s ease;
}

.faq-section .faq-item[open] {
    border-color: var(--accent-indigo); 
    box-shadow: 0 4px 20px rgba(79, 70, 229, 0.15);
}

.faq-section summary.faq-question {
    padding: 16px 20px; cursor: pointer;
    font-weight: 600; color: var(--text-primary);
    list-style: none; position: relative;
    display: flex; justify-content: space-between;
    align-items: center; transition: background 0.2s;
}

.faq-section summary.faq-question:hover { background-color: #F9FAFB; }

.faq-section .faq-item[open] summary.faq-question {
    color: var(--accent-indigo);
    background: var(--accent-indigo-light);
}

.faq-question::after {
    content: '+'; font-size: 20px;
    color: var(--text-secondary); font-weight: 400; line-height: 1;
}
.faq-question .icon-plus { display: none; }

.faq-section .faq-item[open] summary.faq-question::after {
    content: '−'; color: var(--accent-indigo);
}

.faq-answer {
    padding: 20px; color: var(--text-secondary);
    line-height: 1.6; font-size: 15px;
}

/* --- МОБИЛЬНАЯ АДАПТАЦИЯ --- */
@media (max-width: 900px) {
    .formulas-grid { grid-template-columns: 1fr; gap: 16px; margin-bottom: 32px; }
    
    .icon-heading { font-size: 20px; gap: 12px; margin-bottom: 20px; }
    .header-icon { width: 40px; height: 40px; border-radius: 12px; }
    .header-icon svg { width: 20px; height: 20px; }
    
    .formula-card { 
        padding: 24px; 
        text-align: center; 
        align-items: center; 
    }

    .formula-header {
        align-items: center;
        width: 100%;
    }

    .math-expression {
        width: 100%;
        max-width: 300px;
        margin-left: auto;
        margin-right: auto;
    }

    .info-wrapper { margin-top: 40px; padding-top: 40px; }
}