/* =========================================================
   CALCULADORA DE CARGA TÉRMICA PRO
   ========================================================= */

/* --- FUNDAÇÃO E IDENTIDADE VISUAL --- */
:root {
    /* TEMA CLARO (PADRÃO) */
    --bg: #f0f2f5;
    --surface: #ffffff;
    --text: #212529;
    --text-secondary: #6c757d;
    --border: #dee2e6;
    --shadow: 0 2px 8px rgba(0,0,0,0.07);

    /* Cores de destaque */
    --primary: #2563eb;
    --secondary: #003366;
    --cor-destaque: #ffc107;
    --cor-sucesso: #28a745;
    --cor-erro: #dc3545;
    --accent-light: #fff3cd;

    --radius: 12px;
    --radius-sm: 8px;
    --font: system-ui, -apple-system, 'Segoe UI', sans-serif;
    --transition: 0.3s ease;

    /* Alvo mínimo de toque recomendado (mobile) */
    --tap-min: 44px;
}

body.dark-theme {
    /* TEMA ESCURO */
    --bg: #0a1929;
    --surface: #112233;
    --text: #e9ecef;
    --text-secondary: #8696a7;
    --border: #334b61;
    --shadow: 0 1px 3px rgba(0,0,0,0.4);
    --primary: #3b82f6;
}

/* --- ESTILOS GERAIS E LAYOUT --- */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { -webkit-tap-highlight-color: transparent; }
body {
    font-family: var(--font);
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
    transition: background-color var(--transition), color var(--transition);
    overflow-x: hidden;
    -webkit-text-size-adjust: 100%;
}

/* Foco visível para navegação por teclado/leitor de tela */
a:focus-visible, button:focus-visible, input:focus-visible, label:focus-visible {
    outline: 3px solid var(--primary);
    outline-offset: 2px;
}

.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    width: 100%;
}

/* Ícones SVG locais (substituem FontAwesome/CDN) */
.icon {
    width: 1.1em;
    height: 1.1em;
    fill: none;
    stroke: currentColor;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
    vertical-align: -0.2em;
    flex-shrink: 0;
}
.icon-solid { fill: currentColor; stroke: none; }

.visually-hidden {
    position: absolute;
    width: 1px; height: 1px;
    overflow: hidden;
    clip: rect(0,0,0,0);
    white-space: nowrap;
}

/* --- HEADER REFINADO --- */
.app-header {
    background: linear-gradient(145deg, #0f172a 0%, #1e3a5f 50%, #1a365d 100%);
    color: white;
    padding: 0.9rem 1rem;
    box-shadow: var(--shadow);
    z-index: 1000;
    position: sticky;
    top: 0;
}
.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1600px;
    margin: 0 auto;
}
.header-content h1 {
    font-size: 1rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin: 0;
}
.theme-switcher {
    display: flex;
    align-items: center;
    gap: .5rem;
}
.switch { position: relative; display: inline-block; width: 50px; height: 28px; }
.switch input { opacity: 0; width: 0; height: 0; position: absolute; }
.slider { position: absolute; cursor: pointer; top: 0; left: 0; right: 0; bottom: 0; background-color: rgba(255,255,255,0.25); transition: .4s; border-radius: 28px; }
.slider:before { position: absolute; content: ""; height: 22px; width: 22px; left: 3px; bottom: 3px; background-color: white; transition: .4s; border-radius: 50%; }
input:checked + .slider { background-color: var(--cor-destaque); }
input:checked + .slider:before { transform: translateX(22px); }

/* --- LAYOUT PRINCIPAL (GRID) --- */
.app-main {
    flex-grow: 1;
    display: grid;
    grid-template-columns: 1fr;
    gap: 1rem;
    padding: 1rem;
    width: 100%;
}
.app-main > * { min-width: 0; }

#inputs-column, #outputs-column {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

/* --- CARDS E TÍTULOS --- */
.card {
    background-color: var(--surface);
    padding: 1.25rem;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    box-shadow: var(--shadow);
    transition: all var(--transition);
    display: flex;
    flex-direction: column;
}
.card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.75rem;
    margin: 0 0 1.25rem 0;
    padding-bottom: 0.75rem;
    border-bottom: 1px solid var(--border);
}
.card h2 {
    font-size: 1.05rem;
    font-weight: 700;
    color: var(--primary);
    margin: 0;
    display: flex;
    align-items: center;
    gap: 0.6rem;
}
body.dark-theme .card h2 { color: var(--text); }

.info-btn {
    width: var(--tap-min);
    height: var(--tap-min);
    min-width: var(--tap-min);
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: none;
    color: var(--text-secondary);
    border-radius: 50%;
    cursor: pointer;
    transition: background-color .2s, color .2s;
}
.info-btn:hover, .info-btn:active { background-color: var(--bg); color: var(--primary); }

/* --- FORMULÁRIOS E INPUTS --- */
.input-group { margin-bottom: 1rem; }
.input-group label {
    display: block;
    font-size: .8rem;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: .4rem;
}
.input-group label span {
    font-weight: 400;
    font-size: 0.75rem;
    opacity: 0.8;
}
.input-group input[type="number"] {
    width: 100%;
    min-height: var(--tap-min);
    padding: .7rem .85rem;
    border: 2px solid var(--border);
    border-radius: var(--radius-sm);
    background-color: var(--bg);
    color: var(--text);
    font-size: 1rem; /* >=16px evita zoom automático no iOS */
    transition: border-color .2s, box-shadow .2s;
}
.input-group input:focus {
    outline: none;
    border-color: var(--cor-destaque);
    box-shadow: 0 0 0 3px rgba(255, 193, 7, 0.15);
}
.input-group input.input-invalid {
    border-color: var(--cor-erro);
}
.input-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(130px, 100%), 1fr));
    gap: 1rem;
}

/* --- AÇÕES (RESET) --- */
.actions-row {
    display: flex;
    justify-content: flex-end;
    padding: 0 1rem;
}
.btn-reset {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-height: var(--tap-min);
    padding: 0 1rem;
    background-color: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    color: var(--cor-erro);
    font-weight: 600;
    font-size: 0.85rem;
    cursor: pointer;
    transition: background-color .2s;
}
.btn-reset:hover, .btn-reset:active { background-color: rgba(220, 53, 69, 0.08); }

/* --- RESULTADOS --- */
.resultado-container { padding: 1rem; border-radius: var(--radius-sm); transition: all 0.3s ease; }
.resultado-display { display: flex; flex-direction: column; gap: 0.5rem; text-align: center; }
.result-main-text { font-size: 1.8rem; font-weight: bold; color: var(--primary); }
.result-sub-text { color: var(--text-secondary); font-size: 0.95rem; font-weight: 600;}
.resultado-container.success { border-left: 4px solid var(--primary); background-color: rgba(37, 99, 235, 0.05); }

body.dark-theme .resultado-container.success { background-color: rgba(59, 130, 246, 0.1); }
body.dark-theme .result-main-text { color: var(--cor-destaque); }

.empty-state {
    text-align: center;
    color: var(--text-secondary);
    font-size: 0.85rem;
    padding: 0.5rem 0 0;
}

.result-recomendacao {
    margin-top: 0.85rem;
    padding-top: 0.75rem;
    border-top: 1px dashed var(--border);
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
}
.result-recomendacao strong { color: var(--text); }

/* Comportamento sticky para o card de resultados no mobile */
#outputs-column {
    position: sticky;
    bottom: 1rem;
    z-index: 100;
}
#results-card {
    box-shadow: 0 -4px 15px rgba(0,0,0,0.1);
}

/* --- MODAL DE INFORMAÇÃO (FATORES) --- */
.info-modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: flex-end;
    justify-content: center;
    z-index: 2000;
    opacity: 0;
    visibility: hidden;
    transition: opacity .25s ease;
}
.info-modal-overlay.open {
    opacity: 1;
    visibility: visible;
}
.info-modal {
    background-color: var(--surface);
    color: var(--text);
    width: 100%;
    max-width: 480px;
    border-radius: var(--radius) var(--radius) 0 0;
    padding: 1.25rem;
    max-height: 70vh;
    overflow-y: auto;
    transform: translateY(20px);
    transition: transform .25s ease;
    box-shadow: 0 -8px 24px rgba(0,0,0,0.2);
}
.info-modal-overlay.open .info-modal {
    transform: translateY(0);
}
.info-modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}
.info-modal-header h3 {
    font-size: 1rem;
    color: var(--primary);
}
.info-modal-close {
    width: var(--tap-min);
    height: var(--tap-min);
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    border-radius: 50%;
}
.info-modal-close:hover { background-color: var(--bg); }
.info-modal dl {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 0.5rem 1rem;
}
.info-modal dt { color: var(--text-secondary); font-size: 0.85rem; }
.info-modal dd { font-weight: 700; font-size: 0.85rem; text-align: right; }
.info-modal p.info-note {
    margin-top: 1rem;
    font-size: 0.78rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

@media (min-width: 700px) {
    .app-main {
        grid-template-columns: 1fr 400px;
        gap: 1.5rem;
        padding: 1.5rem;
        max-width: 1200px;
        margin: 0 auto;
        align-items: start;
    }
    #outputs-column {
        position: sticky;
        top: 80px;
        bottom: auto;
    }
    .info-modal-overlay { align-items: center; }
    .info-modal { border-radius: var(--radius); transform: translateY(0) scale(0.95); }
    .info-modal-overlay.open .info-modal { transform: scale(1); }
}

/* Respeita preferência de redução de movimento */
@media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
    }
}