/* css */
:root{
    --brand-500: #c62828; /* rojo principal */
    --brand-600: #b71c1c;
    --accent-500: #ff9800; /* naranja/acento */
    --muted-100: #faf5ef; /* fondo suave */
    --card-bg: #ffffff;
    --text-900: #222222;
    --muted-600: #7a6f63;
    --success: #2e7d32;
    --danger: #b00020;
    --radius: 10px;
    --shadow-1: 0 6px 18px rgba(34,34,34,0.08);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Montserrat', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(180deg, var(--muted-100) 0%, #fff 100%);
    color: var(--text-900);
    min-height: 100vh;
    padding: 24px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1100px;
    margin: 0 auto;
}

/* Header / Branding */
header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    background: linear-gradient(90deg, var(--brand-500) 0%, var(--brand-600) 100%);
    color: white;
    padding: 22px 28px;
    border-radius: 12px;
    box-shadow: var(--shadow-1);
    margin-bottom: 36px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 18px;
}

.logo {
    width: 64px;
    height: 64px;
    background: white;
    border-radius: 8px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: var(--brand-600);
    font-weight: 800;
    font-size: 1.05rem;
    box-shadow: 0 6px 18px rgba(0,0,0,0.08);
}

header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    letter-spacing: 0.2px;
}

.subtitle {
    font-size: 0.95rem;
    opacity: 0.95;
    color: rgba(255,255,255,0.9);
}

/* Layout */
main {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
    gap: 28px;
    margin-bottom: 36px;
}

/* Card */
.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow-1);
    position: relative;
    overflow: hidden;
    border-left: 6px solid rgba(0,0,0,0.03);
}

.card::before{
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 6px;
    height: 100%;
    background: linear-gradient(180deg, var(--accent-500), rgba(204,102,0,0.7));
    border-top-left-radius: var(--radius);
    border-bottom-left-radius: var(--radius);
}

.card h2 {
    color: var(--brand-600);
    margin-bottom: 16px;
    font-size: 1.25rem;
    font-weight: 700;
}

/* Form */
.form-group {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

input[type="text"], input[type="number"], input {
    padding: 12px 14px;
    border: 1px solid #e6e0da;
    border-radius: 8px;
    font-size: 0.98rem;
    transition: box-shadow 0.18s, border-color 0.18s;
    background: #fff;
    color: var(--text-900);
}

input:focus {
    outline: none;
    border-color: var(--brand-500);
    box-shadow: 0 6px 18px rgba(198,40,40,0.08);
}

/* Buttons */
button {
    padding: 12px 18px;
    background: linear-gradient(90deg, var(--brand-500) 0%, var(--brand-600) 100%);
    color: white;
    border: none;
    border-radius: 8px;
    font-size: 0.98rem;
    font-weight: 700;
    cursor: pointer;
    transition: transform 0.12s ease, box-shadow 0.12s ease, opacity 0.12s;
    box-shadow: 0 8px 20px rgba(198,40,40,0.12);
    align-self: start;
}

button:hover {
    transform: translateY(-2px);
    opacity: 0.98;
}

button:active {
    transform: translateY(0);
}

/* Result messages */
.result {
    margin-top: 18px;
    padding: 14px;
    border-radius: 8px;
    font-size: 0.95rem;
    display: none;
    line-height: 1.35;
    border: 1px solid rgba(0,0,0,0.04);
}

.result.success {
    background: #eef7ee;
    color: var(--success);
    border-color: rgba(46,125,50,0.12);
    display: block;
}

.result.error {
    background: #fff0f0;
    color: var(--danger);
    border-color: rgba(176,0,32,0.08);
    display: block;
}

.result.info {
    background: #fff8f2;
    color: #7a4a18;
    border-color: rgba(255,152,0,0.08);
    display: block;
}

/* Footer */
footer {
    text-align: center;
    color: var(--muted-600);
    padding: 18px;
    font-size: 0.95rem;
    margin-top: 12px;
}

/* Responsive tweaks */
@media (max-width: 768px) {
    header {
        flex-direction: column;
        align-items: flex-start;
        gap: 12px;
    }

    .logo { width: 56px; height: 56px; }
    header h1 { font-size: 1.25rem; }
    main { grid-template-columns: 1fr; }
}