/* =====================================================
   SentirIA - Landing Page Styles
   Paleta: navy (#1E2761), crimson (#A51C30), verde (#27AE60)
   ===================================================== */

:root {
    --navy: #1E2761;
    --navy-light: #2a3580;
    --navy-dark: #141c4a;
    --crimson: #A51C30;
    --crimson-light: #c4283e;
    --green: #27AE60;
    --green-light: #2ecc71;
    --white: #ffffff;
    --gray-50: #f8f9fa;
    --gray-100: #f1f3f5;
    --gray-200: #e9ecef;
    --gray-300: #dee2e6;
    --gray-500: #6c757d;
    --gray-700: #495057;
    --gray-900: #212529;
    --shadow: 0 4px 6px -1px rgba(0,0,0,.1), 0 2px 4px -2px rgba(0,0,0,.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,.1), 0 4px 6px -4px rgba(0,0,0,.1);
    --radius: 12px;
    --transition: .3s ease;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, sans-serif;
    color: var(--gray-900);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* --- NAV --- */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(30, 39, 97, .95);
    backdrop-filter: blur(10px);
    padding: 16px 0;
    transition: var(--transition);
}
.navbar.scrolled {
    padding: 10px 0;
    box-shadow: var(--shadow);
}
.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.logo {
    font-family: 'Playfair Display', serif;
    font-size: 1.5rem;
    color: var(--white);
    text-decoration: none;
    font-weight: 700;
}
.logo span { color: var(--green-light); }

.nav-links {
    display: flex;
    align-items: center;
    gap: 28px;
    list-style: none;
}
.nav-links a {
    color: rgba(255,255,255,.85);
    text-decoration: none;
    font-size: .9rem;
    font-weight: 500;
    transition: var(--transition);
}
.nav-links a:hover { color: var(--white); }

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--white);
    transition: var(--transition);
}

/* --- BUTTONS --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    font-size: .95rem;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
}
.btn-sm { padding: 8px 18px; font-size: .85rem; }
.btn-lg { padding: 16px 36px; font-size: 1.05rem; }
.btn-primary { background: var(--green); color: var(--white); }
.btn-primary:hover { background: var(--green-light); transform: translateY(-2px); box-shadow: var(--shadow-lg); }
.btn-crimson { background: var(--crimson); color: var(--white); }
.btn-crimson:hover { background: var(--crimson-light); transform: translateY(-2px); }
.btn-outline { border-color: var(--white); color: var(--white); background: transparent; }
.btn-outline:hover { background: var(--white); color: var(--navy); }
.btn-outline-light { border-color: rgba(255,255,255,.5); color: var(--white); background: transparent; border-radius: 6px; }
.btn-outline-light:hover { background: rgba(255,255,255,.15); }

/* --- HERO --- */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy) 50%, var(--navy-light) 100%);
    overflow: hidden;
    padding: 120px 0 80px;
}
.hero-bg {
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 70% 30%, rgba(39,174,96,.15) 0%, transparent 50%),
                radial-gradient(circle at 20% 80%, rgba(165,28,48,.1) 0%, transparent 50%);
}
.hero-content {
    position: relative;
    z-index: 1;
    max-width: 800px;
}
.hero h1 {
    font-family: 'Playfair Display', serif;
    font-size: clamp(2rem, 4vw, 3.2rem);
    color: var(--white);
    line-height: 1.25;
    margin-bottom: 24px;
}
.highlight { color: var(--green-light); }
.hero-subtitle {
    font-size: 1.15rem;
    color: rgba(255,255,255,.8);
    margin-bottom: 36px;
    max-width: 650px;
    line-height: 1.7;
}
.hero-buttons { display: flex; gap: 16px; flex-wrap: wrap; margin-bottom: 40px; }
.hero-trust {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
}
.hero-trust span {
    color: rgba(255,255,255,.6);
    font-size: .85rem;
    padding-left: 20px;
    position: relative;
}
.hero-trust span::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--green);
}

/* --- SECTIONS --- */
.section { padding: 100px 0; }
.section-alt { background: var(--gray-50); }
.section-title {
    font-family: 'Playfair Display', serif;
    font-size: 2.2rem;
    text-align: center;
    margin-bottom: 12px;
    color: var(--navy);
}
.section-subtitle {
    text-align: center;
    color: var(--gray-500);
    font-size: 1.1rem;
    margin-bottom: 60px;
}

/* --- STEPS --- */
.steps-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.step-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 40px 32px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}
.step-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.step-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--navy), var(--navy-light));
    color: var(--white);
    margin-bottom: 24px;
}
.step-card h3 { font-size: 1.2rem; margin-bottom: 12px; color: var(--navy); }
.step-card p { color: var(--gray-500); font-size: .95rem; }

/* --- MODES --- */
.modes-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 32px; max-width: 900px; margin: 0 auto; }
.mode-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 48px 36px;
    box-shadow: var(--shadow);
    position: relative;
    transition: var(--transition);
}
.mode-card.featured {
    border: 2px solid var(--crimson);
    transform: scale(1.03);
}
.mode-card:hover { box-shadow: var(--shadow-lg); }
.mode-badge {
    display: inline-block;
    padding: 4px 16px;
    border-radius: 20px;
    font-size: .75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: .5px;
    margin-bottom: 16px;
}
.mode-badge.free { background: var(--green); color: var(--white); }
.mode-badge.inst { background: var(--crimson); color: var(--white); }
.mode-card h3 { font-size: 1.4rem; margin-bottom: 12px; color: var(--navy); }
.mode-card > p { color: var(--gray-500); margin-bottom: 24px; }
.mode-card ul { list-style: none; margin-bottom: 32px; }
.mode-card li {
    padding: 8px 0 8px 24px;
    position: relative;
    color: var(--gray-700);
    font-size: .95rem;
}
.mode-card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--green);
    font-weight: 700;
}

/* --- SIGNALS --- */
.signals-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.signal-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 32px 16px;
    background: var(--white);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    transition: var(--transition);
}
.signal-item:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.signal-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: var(--gray-100);
    color: var(--navy);
    margin-bottom: 16px;
}
.signal-item span { font-weight: 600; font-size: .9rem; color: var(--gray-700); }

/* --- ETHICS --- */
.ethics-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 900px; margin: 0 auto; }
.ethics-card {
    background: var(--white);
    border-radius: var(--radius);
    padding: 32px;
    border-left: 4px solid var(--green);
    box-shadow: var(--shadow);
}
.ethics-card h4 { color: var(--navy); margin-bottom: 8px; }
.ethics-card p { color: var(--gray-500); font-size: .95rem; }

/* --- INSTITUTIONS --- */
.inst-types { display: grid; grid-template-columns: repeat(5, 1fr); gap: 20px; margin-bottom: 60px; }
.inst-type {
    text-align: center;
    padding: 32px 16px;
    background: var(--gray-50);
    border-radius: var(--radius);
    transition: var(--transition);
}
.inst-type:hover { background: var(--white); box-shadow: var(--shadow); }
.inst-type h4 { color: var(--navy); margin-bottom: 8px; font-size: .95rem; }
.inst-type p { color: var(--gray-500); font-size: .85rem; }

/* --- CONTACT FORM --- */
.contact-form-wrapper {
    max-width: 700px;
    margin: 0 auto;
    background: var(--white);
    border-radius: var(--radius);
    padding: 48px;
    box-shadow: var(--shadow-lg);
}
.contact-form-wrapper h3 {
    text-align: center;
    color: var(--navy);
    font-size: 1.5rem;
    margin-bottom: 32px;
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.form-group { margin-bottom: 20px; }
.form-group label {
    display: block;
    font-weight: 600;
    font-size: .9rem;
    margin-bottom: 6px;
    color: var(--gray-700);
}
.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--gray-200);
    border-radius: 8px;
    font-size: .95rem;
    font-family: inherit;
    transition: var(--transition);
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--navy);
    box-shadow: 0 0 0 3px rgba(30,39,97,.1);
}
.form-result { margin-top: 16px; text-align: center; font-weight: 500; }
.form-result.success { color: var(--green); }
.form-result.error { color: var(--crimson); }

/* --- FAQ --- */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
    background: var(--white);
    border-radius: var(--radius);
    margin-bottom: 12px;
    box-shadow: var(--shadow);
    overflow: hidden;
}
.faq-question {
    width: 100%;
    padding: 20px 24px;
    background: none;
    border: none;
    text-align: left;
    font-size: 1rem;
    font-weight: 600;
    color: var(--navy);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: inherit;
}
.faq-question::after {
    content: '+';
    font-size: 1.5rem;
    font-weight: 300;
    color: var(--gray-500);
    transition: var(--transition);
}
.faq-item.active .faq-question::after {
    content: '−';
    color: var(--crimson);
}
.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height .3s ease;
}
.faq-answer p { padding: 0 24px 20px; color: var(--gray-500); line-height: 1.7; }

/* --- FOOTER --- */
.footer {
    background: var(--navy-dark);
    color: rgba(255,255,255,.7);
    padding: 60px 0 30px;
}
.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}
.footer-brand p { margin-top: 12px; font-size: .9rem; line-height: 1.6; }
.footer-links h4 { color: var(--white); font-size: .9rem; margin-bottom: 16px; }
.footer-links ul { list-style: none; }
.footer-links li { margin-bottom: 8px; }
.footer-links a { color: rgba(255,255,255,.6); text-decoration: none; font-size: .9rem; transition: var(--transition); }
.footer-links a:hover { color: var(--white); }
.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1);
    padding-top: 24px;
    text-align: center;
    font-size: .85rem;
}
.footer-disclaimer { margin-top: 8px; font-size: .8rem; color: rgba(255,255,255,.4); }

/* --- RESPONSIVE --- */
@media (max-width: 992px) {
    .steps-grid { grid-template-columns: 1fr; max-width: 500px; margin: 0 auto; }
    .signals-grid { grid-template-columns: repeat(2, 1fr); }
    .inst-types { grid-template-columns: repeat(2, 1fr); }
    .footer-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .nav-toggle { display: flex; }
    .nav-links {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--navy);
        flex-direction: column;
        padding: 20px 24px;
        gap: 16px;
    }
    .nav-links.active { display: flex; }

    .hero { padding: 100px 0 60px; }
    .hero h1 { font-size: 1.8rem; }
    .hero-subtitle { font-size: 1rem; }

    .modes-grid { grid-template-columns: 1fr; }
    .mode-card.featured { transform: none; }
    .ethics-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; }
    .contact-form-wrapper { padding: 32px 24px; }
    .inst-types { grid-template-columns: 1fr; }
    .footer-grid { grid-template-columns: 1fr; }
}