/* --- Lighting Theme --- */
:root {
    --lit-bg: #FEF9C3;       /* Light Yellow */
    --lit-card-bg: linear-gradient(135deg, #FACC15 0%, #EAB308 100%);
    --lit-accent: #CA8A04;   /* Dark Yellow/Gold */
    --lit-text: #422006;     /* Dark Brown */
    --lit-hover: #FEFCE8;    /* Very Light Yellow for hover */
}

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

/* Общие переопределения */
.calc-grid { display: grid; grid-template-columns: 1fr; gap: 24px; align-items: start; }
@media (min-width: 900px) { .calc-grid { grid-template-columns: 1.1fr 0.9fr; } }

/* Inputs */
.section-label {
    font-size: 11px; text-transform: uppercase; letter-spacing: 1px;
    color: #9CA3AF; margin-bottom: 12px; font-weight: 700;
}

.input-group { margin-bottom: 24px; position: relative; }
.input-group label { 
    display: block; 
    font-size: 14px; font-weight: 700; color: #4B5563; margin-bottom: 8px; 
}

.input-wrapper { position: relative; display: flex; align-items: center; }
.input-wrapper input, .input-wrapper select {
    width: 100%; padding: 14px; padding-right: 40px;
    font-size: 16px; font-weight: 600;
    border: 2px solid #E5E7EB; border-radius: 12px;
    outline: none; transition: border 0.2s;
    background: #fff; font-family: var(--font-main); color: var(--text-primary);
    appearance: none;
}
.input-wrapper input:focus, .input-wrapper select:focus { border-color: var(--lit-accent); }
.suffix { position: absolute; right: 14px; color: #9CA3AF; font-weight: 500; pointer-events: none; }

.row-2-col { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* --- CUSTOM SELECT --- */
.custom-select-wrapper {
    position: relative;
    user-select: none;
    font-family: var(--font-main);
}

.custom-select-trigger {
    position: relative;
    display: flex; align-items: center; justify-content: space-between;
    padding: 14px;
    font-size: 16px; font-weight: 600; color: var(--text-primary);
    background: #fff;
    border: 2px solid #E5E7EB; border-radius: 12px;
    cursor: pointer; transition: all 0.2s;
    min-width: 0;
    height: auto;
}

.selected-text {
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
    margin-right: 12px;
    flex-grow: 1;
    line-height: 1.4;
    text-align: left;
}

.custom-select-wrapper.open .custom-select-trigger {
    border-color: var(--lit-accent);
    box-shadow: 0 0 0 4px rgba(234, 179, 8, 0.1);
}

.arrow-icon {
    font-size: 20px; color: #9CA3AF; transition: transform 0.3s;
    flex-shrink: 0;
    align-self: center;
}
.custom-select-wrapper.open .arrow-icon { transform: rotate(180deg); color: var(--lit-accent); }

/* Выпадающий список */
.custom-options {
    position: absolute; top: calc(100% + 8px); left: 0; right: 0;
    background: #fff; border: 2px solid #E5E7EB; border-radius: 12px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
    z-index: 100;
    opacity: 0; visibility: hidden; transform: translateY(-10px);
    transition: all 0.2s cubic-bezier(0.25, 0.8, 0.25, 1);
    max-height: 300px; overflow-y: auto;
}

.custom-select-wrapper.open .custom-options {
    opacity: 1; visibility: visible; transform: translateY(0);
}

.custom-option {
    padding: 12px 14px;
    font-size: 14px; font-weight: 500; color: #374151;
    cursor: pointer; transition: background 0.1s;
    white-space: normal;
    line-height: 1.4;
    border-bottom: 1px solid #F9FAFB;
}
.custom-option:last-child { border-bottom: none; }

.custom-option:hover { background: var(--lit-hover); color: var(--lit-accent); }
.custom-option.selected { background: #FEF3C7; color: var(--lit-accent); font-weight: 700; }

.opt-group-label {
    padding: 8px 14px; font-size: 11px; text-transform: uppercase; letter-spacing: 0.5px;
    color: #9CA3AF; font-weight: 700; background: #F9FAFB; border-bottom: 1px solid #F3F4F6;
    margin-top: 0;
}

/* --- RADIO CHIPS & CHECKBOX --- */
.radio-chips { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 8px; }
.chip { cursor: pointer; }
.chip input { display: none; }
.chip span {
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    text-align: center; border: 2px solid #E5E7EB; border-radius: 12px;
    padding: 10px 4px; background: #fff; height: 100%;
    font-weight: 700; font-size: 14px; color: #374151; transition: all 0.2s;
}
.chip span small { font-weight: 500; font-size: 11px; color: #9CA3AF; margin-top: 2px; }

.chip input:checked + span {
    border-color: var(--lit-accent); background: #FEFCE8;
    color: var(--lit-accent); box-shadow: 0 4px 12px rgba(234, 179, 8, 0.2);
}
.chip input:checked + span small { color: var(--lit-accent); opacity: 0.8; }

.mt-2 { margin-top: 10px; }
.mt-3 { margin-top: 20px; }

label.checkbox-simple { 
    display: flex !important; align-items: center; gap: 10px; 
    cursor: pointer; font-size: 14px; font-weight: 600; color: #4B5563; margin-bottom: 0;
}
.checkbox-simple input { 
    width: 18px; height: 18px; accent-color: var(--lit-accent); cursor: pointer; margin: 0; 
}

/* Range Slider */
input[type=range] { width: 100%; accent-color: var(--lit-accent); margin-bottom: 8px; cursor: pointer; }
.range-labels { display: flex; justify-content: space-between; font-size: 12px; color: #6B7280; font-weight: 600; }
#temp-val { color: var(--lit-accent); font-weight: 800; }

/* --- RESULT CARD --- */
.card--light {
    background: var(--lit-card-bg);
    color: #fff; border: none;
    box-shadow: 0 10px 30px rgba(202, 138, 4, 0.4);
    position: relative; overflow: hidden;
}
.card--light h2 { color: rgba(255,255,255,0.9); font-size: 16px; margin-bottom: 4px; text-align: center; }
.result-big { text-align: center; font-size: 56px; font-weight: 800; line-height: 1; margin: 16px 0; text-shadow: 0 2px 4px rgba(0,0,0,0.1); }
.unit { font-size: 24px; font-weight: 600; opacity: 0.9; }
.result-desc { text-align: center; font-size: 15px; color: rgba(255,255,255,0.9); margin-bottom: 24px; }
.summary-divider { height: 1px; background: rgba(255,255,255,0.2); margin: 20px 0; }

/* --- VISUAL ROOM --- */
.room-visual-container {
    width: 100%; height: 180px;
    background: #0F172A; border-radius: 12px;
    position: relative; overflow: hidden; margin-bottom: 12px;
    border: 3px solid rgba(255,255,255,0.1); box-shadow: inset 0 0 30px #000;
}
.room-box {
    width: 100%; height: 100%; position: relative;
    background-image: repeating-linear-gradient(90deg, rgba(255,255,255,0.03) 0px, rgba(255,255,255,0.03) 1px, transparent 1px, transparent 40px);
    background-color: #1E293B; transition: background-color 0.3s;
}
.furniture-sofa {
    position: absolute; bottom: 0; left: 50%; transform: translateX(-120%);
    width: 90px; height: 45px; background: #334155;
    border-radius: 12px 12px 0 0; box-shadow: 2px -2px 10px rgba(0,0,0,0.3); z-index: 1;
}
.furniture-table {
    position: absolute; bottom: 0; left: 50%; transform: translateX(20%);
    width: 70px; height: 35px; background: #475569;
    border-radius: 4px 4px 0 0; box-shadow: -2px -2px 10px rgba(0,0,0,0.3); z-index: 1;
}
.room-box::after {
    content: ''; position: absolute; top: 30px; left: 20px;
    width: 40px; height: 60px; background: #0F172A;
    border: 2px solid #334155; border-radius: 4px; box-shadow: 0 0 15px rgba(255,255,255,0.05);
}
.room-overlay {
    position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    z-index: 2; pointer-events: none; transition: opacity 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.light-beam {
    position: absolute; top: -10px; left: 50%; transform: translateX(-50%);
    width: 60px; height: 30px; background: #fff;
    border-radius: 50%; z-index: 3;
    transition: box-shadow 0.2s ease-out, background-color 0.2s;
}
.visual-status {
    text-align: center; font-size: 13px; color: rgba(255,255,255,0.9); margin-top: 10px; 
    font-weight: 700; text-shadow: 0 1px 2px rgba(0,0,0,0.2);
}
.info-row { display: flex; align-items: start; gap: 8px; font-size: 12px; color: rgba(255,255,255,0.8); line-height: 1.4; }
.info-row i { font-size: 16px; margin-top: -2px; }
.bullet-list { padding-left: 20px; line-height: 1.6; color: var(--text-secondary); font-size: 14px; }
.bullet-list li { margin-bottom: 8px; }

/* --- НОВЫЕ ИНФОРМАЦИОННЫЕ БЛОКИ (Адаптация под Lighting/Yellow) --- */

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

.info-wrapper .container {
    max-width: 800px;
    margin: 0 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: #EF4444; }

/* 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: 0 4px 20px rgba(0,0,0,0.03);
    border-radius: 24px; 
    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: 0 12px 32px rgba(0,0,0,0.08); }

/* 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;
}

.formula-card small {
    display: block; margin-top: 12px; font-size: 12px; color: var(--text-secondary); opacity: 0.7;
}

.math-expression {
    background: #F9FAFB;
    border: 1px solid #E5E7EB;
    padding: 12px 16px;
    border-radius: 12px;
    font-weight: 700;
    color: var(--lit-accent); /* Accent Color */
    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 0;
}

/* 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 (Новый стиль под Lighting) */
.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(--lit-accent); 
    box-shadow: 0 4px 20px rgba(202, 138, 4, 0.15); /* Accent Shadow */
}

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;
}

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

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

.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(--lit-accent);
}

.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; }
}