@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;600;700&display=swap');

:root {
    --primary: #6366f1;
    --primary-hover: #4f46e5;
    --bg: #f8fafc;
    --text: #0f172a;
    --girl: #f472b6;
    --boy: #38bdf8;
    --glass: rgba(255, 255, 255, 0.8);
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg);
    background-image: radial-gradient(at 0% 0%, rgba(99, 102, 241, 0.15) 0px, transparent 50%), 
                      radial-gradient(at 100% 100%, rgba(244, 114, 182, 0.15) 0px, transparent 50%);
    color: var(--text);
    margin: 0;
    min-height: 100vh;
}

.container { max-width: 1000px; margin: 0 auto; padding: 40px 20px; }

/* Header & Cards */
.glass-card {
    background: var(--glass);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 24px;
    padding: 40px;
    box-shadow: 0 20px 25px -5px rgba(0,0,0,0.05);
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    text-align: center;
    background: linear-gradient(to right, #6366f1, #ec4899);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 10px;
}

/* Forms */
.form-group { margin-bottom: 20px; }
label { font-weight: 600; font-size: 0.9rem; color: #475569; display: block; margin-bottom: 8px; }
input[type="date"] {
    width: 100%; padding: 14px; border-radius: 12px; border: 1px solid #e2e8f0;
    font-size: 1rem; transition: all 0.3s;
}
input:focus { border-color: var(--primary); outline: none; box-shadow: 0 0 0 4px rgba(99, 102, 241, 0.1); }

.btn-main {
    width: 100%; background: var(--primary); color: white; padding: 16px;
    border: none; border-radius: 12px; font-weight: 700; font-size: 1.1rem;
    cursor: pointer; transition: all 0.3s;
}
.btn-main:hover { background: var(--primary-hover); transform: translateY(-2px); }

/* Prediction Results */
.result-badge {
    display: inline-block; padding: 8px 20px; border-radius: 99px;
    font-weight: 700; text-transform: uppercase; letter-spacing: 1px;
}
.boy { background: #e0f2fe; color: #0369a1; }
.girl { background: #fce7f3; color: #be185d; }

.grid-methods { display: grid; grid-template-columns: repeat(auto-fit, minmax(200px, 1fr)); gap: 20px; margin-top: 30px; }
.method-box { background: white; padding: 20px; border-radius: 16px; border: 1px solid #f1f5f9; text-align: center; }

/* Loader */
.spinner {
    width: 40px; height: 40px; border: 4px solid #f3f3f3; border-top: 4px solid var(--primary);
    border-radius: 50%; animation: spin 1s linear infinite; margin: 0 auto;
}
@keyframes spin { 0% { transform: rotate(0deg); } 100% { transform: rotate(360deg); } }
.glass-card {
    animation: fadeInUp 0.6s ease-out forwards;
    opacity: 0;
}

@keyframes fadeInUp {
    from { transform: translateY(30px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.result-badge {
    font-size: 0.75rem;
    padding: 5px 12px;
}

/* Colores de marca más "Luxury" */
:root {
    --primary: #4338ca;
    --boy: #0ea5e9;
    --girl: #d946ef;
}