:root {
    /* --- TEMA DARK (Por defecto) --- */
    --bg-main: #0f1214;
    --bg-gradient-start: #1a2a3a;
    --bg-gradient-end: #0f1214;
    --text-main: #f0f0f0;
    --text-title: #ffffff;
    --text-muted: #888888;
    --text-secondary: rgba(255, 255, 255, 0.5);

    --card-bg: #1e2329;
    --card-border: #343a40;
    --card-shadow: rgba(0, 0, 0, 0.5);

    --input-bg: #2c3238;
    --input-border: #495057;
    --input-text: #ffffff;
    --input-focus-bg: #343a40;
    --input-group-bg: #343a40;
    --input-group-text: #ffffff;
    --placeholder-color: #888888;

    --cyan-primary: #00d2ff;
    --cyan-hover: #ffffff;
    --cyan-shadow: rgba(0, 210, 255, 0.6);
    --cyan-focus: rgba(0, 210, 255, 0.1);

    --guide-bg: rgba(0, 0, 0, 0.4);
    --guide-border: #6c757d;
    --guide-icon-bg: #0055a4;
    --guide-icon-border: rgba(255, 255, 255, 0.2);

    --result-bg: #16191d;
    --result-border: #495057;
    --result-border-style: dashed;

    --bar-bg: #343a40;
    --bar-max: #00d2ff;
    --bar-min: #ffc107;

    --visualizer-bg: #212529;
    --visualizer-border: #343a40;

    --table-bg: rgba(0, 0, 0, 0.3);
    --table-border: #343a40;

    --alert-bg: #2c3238;
    --alert-border: #495057;
    --alert-text: #ffffff;

    --note-info-bg: rgba(13, 202, 240, 0.1);
    --note-info-border: rgba(13, 202, 240, 0.3);
    --note-warning-bg: rgba(255, 193, 7, 0.15);
    --note-warning-border: rgba(255, 193, 7, 0.4);

    --success-border: #00ff9d;
    --success-bg: rgba(0, 255, 157, 0.05);
    --warning-border: #ffc107;
    --warning-bg: rgba(255, 193, 7, 0.05);
    --danger-border: #ff4d5a;
    --danger-bg: rgba(255, 77, 90, 0.05);

    --shadow-color: rgba(0, 0, 0, 0.3);
}

[data-theme='light'] {
    /* --- TEMA LIGHT --- */
    --bg-main: #f8f9fa;
    --bg-gradient-start: #ffffff;
    --bg-gradient-end: #e9ecef;
    --text-main: #212529;
    --text-title: #000000;
    --text-muted: #495057;
    --text-secondary: #6c757d;

    --card-bg: #ffffff;
    --card-border: #dee2e6;
    --card-shadow: rgba(0, 0, 0, 0.1);

    --input-bg: #ffffff;
    --input-border: #ced4da;
    --input-text: #212529;
    --input-focus-bg: #ffffff;
    --input-group-bg: #e9ecef;
    --input-group-text: #495057;
    --placeholder-color: #6c757d;

    --cyan-primary: #0077b6;
    --cyan-hover: #005f8d;
    --cyan-shadow: rgba(0, 119, 182, 0.3);
    --cyan-focus: rgba(0, 119, 182, 0.1);

    --guide-bg: #e7f3ff;
    --guide-border: #b3d9ff;
    --guide-icon-bg: #0077b6;
    --guide-icon-border: rgba(0, 119, 182, 0.3);

    --result-bg: #f8f9fa;
    --result-border: #adb5bd;
    --result-border-style: dashed;

    --bar-bg: #e9ecef;
    --bar-max: #0077b6;
    --bar-min: #ff8800;

    --visualizer-bg: #ffffff;
    --visualizer-border: #dee2e6;

    --table-bg: #f8f9fa;
    --table-border: #dee2e6;

    --alert-bg: #ffffff;
    --alert-border: #dee2e6;
    --alert-text: #212529;

    --note-info-bg: #cfe2ff;
    --note-info-border: #9ec5fe;
    --note-warning-bg: #fff3cd;
    --note-warning-border: #ffe69c;

    --success-border: #198754;
    --success-bg: #d1e7dd;
    --warning-border: #ff8800;
    --warning-bg: #fff3cd;
    --danger-border: #dc3545;
    --danger-bg: #f8d7da;

    --shadow-color: rgba(0, 0, 0, 0.08);
}

/* --- TEMA GLOBAL --- */
body {
    background: radial-gradient(circle at top center, var(--bg-gradient-start) 0%, var(--bg-gradient-end) 80%) !important;
    color: var(--text-main);
}

/* --- CONTENEDOR PRINCIPAL --- */
.content-wrapper {
    max-width: 1600px;
}

/* --- TARJETAS HUD MEJORADAS --- */
.tech-card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    box-shadow: 0 10px 30px var(--card-shadow);
    padding: 2rem;
    margin-bottom: 2rem;
}

.card-header-tech {
    display: flex;
    align-items: center;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid var(--card-border);
    padding-bottom: 1rem;
}

.card-title {
    font-weight: 800;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-title);
    margin: 0;
    font-size: 1.2rem;
}

/* --- INPUTS DE ALTO CONTRASTE --- */
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    color: var(--cyan-primary);
    font-size: 0.85rem;
    text-transform: uppercase;
    font-weight: 800;
    letter-spacing: 0.5px;
    margin-bottom: 0.5rem;
    display: block;
}

.content-wrapper .form-control {
    background-color: var(--input-bg) !important;
    border: 2px solid var(--input-border);
    color: var(--input-text) !important;
    font-family: 'Roboto Mono', monospace;
    font-size: 1.2rem;
    font-weight: 600;
    padding: 0.8rem;
    border-radius: 8px;
}

.content-wrapper .form-control:focus {
    background-color: var(--input-focus-bg) !important;
    border-color: var(--cyan-primary);
    box-shadow: 0 0 0 4px var(--cyan-focus);
}

.content-wrapper .input-group-text {
    background-color: var(--input-group-bg);
    border: 2px solid var(--input-border);
    color: var(--input-group-text);
    border-right: none;
}

.content-wrapper ::placeholder {
    color: var(--placeholder-color) !important;
    opacity: 1;
}

/* --- GUÍA DE AYUDA (HIGH CONTRAST) --- */
.guide-box {
    background-color: var(--guide-bg);
    border: 1px solid var(--guide-border);
    border-radius: 8px;
    padding: 1.2rem;
    margin-top: 2rem;
}

.guide-step {
    display: flex;
    align-items: start;
    margin-bottom: 1.2rem;
    color: var(--text-title);
    font-size: 0.95rem;
    line-height: 1.4;
}

.guide-step:last-child {
    margin-bottom: 0;
}

.guide-icon {
    background: var(--guide-icon-bg);
    color: #fff;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    text-align: center;
    line-height: 28px;
    font-weight: bold;
    font-size: 0.9rem;
    margin-right: 12px;
    flex-shrink: 0;
    border: 1px solid var(--guide-icon-border);
}

/* --- RESULTADOS --- */
.result-container {
    display: flex;
    flex-direction: column;
    height: 90%;
    min-height: 300px;
    justify-content: center;
    align-items: center;
    text-align: center;
    border: 2px var(--result-border-style) var(--result-border);
    border-radius: 12px;
    padding: 2rem;
    background: var(--result-bg);
}

.delta-value {
    font-family: 'Roboto Mono', monospace;
    font-size: 4.5rem;
    font-weight: 800;
    line-height: 1;
    color: var(--text-title);
    margin: 1rem 0;
}

/* --- BARRAS VISUALES --- */
.voltage-visualizer {
    width: 100%;
    margin-top: 2rem;
    background: var(--visualizer-bg);
    padding: 15px;
    border-radius: 8px;
    border: 1px solid var(--visualizer-border);
}

.bar-label {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: var(--text-title);
    margin-bottom: 6px;
    font-weight: 600;
}

.progress-custom {
    height: 14px;
    background-color: var(--bar-bg);
    border-radius: 7px;
    overflow: hidden;
}

.bar-max {
    background: var(--bar-max);
}

.bar-min {
    background: var(--bar-min);
}

/* --- BOTÓN --- */
.btn-scanner {
    background: var(--cyan-primary);
    border: none;
    color: #ffffff !important;
    font-weight: 800;
    text-transform: uppercase;
    padding: 1rem;
    border-radius: 8px;
    width: 100%;
    font-size: 1.1rem;
    margin-top: 1rem;
    transition: all 0.2s;
}

.btn-scanner:hover {
    background: var(--cyan-hover);
    box-shadow: 0 0 20px var(--cyan-shadow);
    color: #ffffff !important;
}

.text-highlight {
    color: var(--cyan-primary);
    font-weight: bold;
}

/* --- TABLA DE REFERENCIA --- */
.reference-table-container {
    margin-top: 3rem;
    padding: 1.2rem;
    background: var(--table-bg);
    border-radius: 8px;
    border: 1px solid var(--table-border);
}

.reference-table-container .table {
    font-size: 0.85rem;
}

.content-wrapper .table-dark {
    --bs-table-bg: var(--card-bg);
    --bs-table-color: var(--text-main);
    --bs-table-border-color: var(--card-border);
}

[data-theme='light'] .content-wrapper .table-dark {
    --bs-table-bg: #ffffff;
    --bs-table-color: #212529;
    --bs-table-border-color: #dee2e6;
}

/* --- ALERTAS Y CONSEJOS --- */
.alert-custom {
    background: var(--alert-bg);
    border: 1px solid var(--alert-border);
    color: var(--alert-text);
}

.alert-note-info {
    background: var(--note-info-bg);
    border: 1px solid var(--note-info-border);
}

.alert-note-warning {
    background: var(--note-warning-bg);
    border: 1px solid var(--note-warning-border);
}

/* --- ESTADOS DE DIAGNÓSTICO --- */
.result-success {
    border-color: var(--success-border) !important;
    background-color: var(--success-bg) !important;
}

.result-warning {
    border-color: var(--warning-border) !important;
    background-color: var(--warning-bg) !important;
}

.result-danger {
    border-color: var(--danger-border) !important;
    background-color: var(--danger-bg) !important;
}

/* --- ESPACIADOR --- */
.spacer {
    height: 150px;
}

/* --- ICONOS EN MODO CLARO --- */
[data-theme='light'] .content-wrapper .text-info {
    color: #0077b6 !important;
}

[data-theme='light'] .content-wrapper .text-warning {
    color: #ff8800 !important;
}

[data-theme='light'] .content-wrapper .text-danger {
    color: #dc3545 !important;
}

[data-theme='light'] .content-wrapper .text-success {
    color: #198754 !important;
}

[data-theme='light'] .content-wrapper .text-primary {
    color: #0077b6 !important;
}

[data-theme='light'] .content-wrapper .text-secondary {
    color: #6c757d !important;
}

[data-theme='light'] .content-wrapper .text-light {
    color: #212529 !important;
}

[data-theme='light'] .content-wrapper .text-white {
    color: #000000 !important;
}

[data-theme='light'] .content-wrapper .text-white-50 {
    color: #495057 !important;
}

[data-theme='light'] .content-wrapper .text-muted {
    color: #6c757d !important;
}

/* --- BADGES EN MODO CLARO --- */
[data-theme='light'] .content-wrapper .badge.bg-success {
    background-color: #198754 !important;
    color: #ffffff !important;
}

[data-theme='light'] .content-wrapper .badge.bg-warning {
    background-color: #ff8800 !important;
    color: #000000 !important;
}

[data-theme='light'] .content-wrapper .badge.bg-danger {
    background-color: #dc3545 !important;
    color: #ffffff !important;
}

[data-theme='light'] .content-wrapper .badge.bg-secondary {
    background-color: #6c757d !important;
    color: #ffffff !important;
}

/* --- SELECTOR DE TEMA --- */
.theme-toggle {
    position: fixed;
    top: 80px;
    right: 20px;
    width: 45px;
    height: 45px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 1000;
    box-shadow: 0 4px 15px var(--shadow-color);
    transition: all 0.3s ease;
}

.theme-toggle:hover {
    transform: scale(1.1);
}

.theme-toggle i {
    font-size: 1.2rem;
    color: var(--cyan-primary);
}

/* --- RESPONSIVE --- */
@media (max-width: 768px) {
    .delta-value {
        font-size: 3rem;
    }

    .tech-card {
        padding: 1.5rem;
    }

    .theme-toggle {
        top: 70px;
        right: 15px;
        width: 40px;
        height: 40px;
    }
}