:root {
    --sky: #38bdf8;
    --sky-soft: #e0f2fe;
    --sky-light: #7dd3fc;
    --text: #0f172a;
}

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

body {
    font-family: 'Inter', sans-serif;
    color: var(--text);
    background: #f8fcff;
}

/* PRELOADER */
#preloader {
    position: fixed;
    inset: 0;
    background: white;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 9999;
}

.loader {
    width: 55px;
    height: 55px;
    border: 6px solid var(--sky-soft);
    border-top: 6px solid var(--sky);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    100% {
        transform: rotate(360deg);
    }
}

/* HEADER */
.header {
    position: fixed;
    width: 100%;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(14px);
    border-bottom: 1px solid #dbeafe;
    z-index: 1000;
}

.container {
    max-width: 1100px;
    margin: auto;
    padding: 15px 20px;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo img {
    height: 100px;
}

.nav a {
    margin-left: 25px;
    text-decoration: none;
    font-weight: 500;
    color: var(--text);
}

.hamburger {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

/* HERO */
.hero {
    min-height: 100vh;
    background: linear-gradient(180deg, var(--sky-soft), #ffffff);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 20px;
}

.hero h1 {
    font-size: 3rem;
    color: var(--sky);
}

.hero p {
    margin-top: 10px;
    font-size: 1.2rem;
}

.btn-whatsapp {
    margin-top: 25px;
    background: #25D366;
    color: white;
    padding: 14px 28px;
    border-radius: 999px;
    text-decoration: none;
    font-size: 1.1rem;
}

.btn-whatsapp i {
    margin-right: 8px;
}

/* SECCIONES */
.section {
    padding: 90px 20px;
    max-width: 900px;
    margin: auto;
    text-align: center;
}

.section h2 {
    color: var(--sky);
    margin-bottom: 20px;
}

.section.alt {
    background: var(--sky-soft);
}

/* FORM */
.contact-form {
    display: grid;
    gap: 15px;
}

.contact-form input,
.contact-form textarea {
    padding: 14px;
    border-radius: 10px;
    border: 1px solid #bae6fd;
}

.contact-form button {
    background: var(--sky);
    color: white;
    border: none;
    padding: 14px;
    border-radius: 999px;
    cursor: pointer;
}

/* BOTÓN ARRIBA */
#backToTop {
    position: fixed;
    bottom: 25px;
    right: 25px;
    width: 46px;
    height: 46px;
    background: var(--sky);
    color: white;
    border: none;
    border-radius: 50%;
    display: none;
    cursor: pointer;
}

/* FOOTER */
.footer {
    background: var(--sky-soft);
    text-align: center;
    padding: 30px 20px;
}

.socials a {
    margin: 0 12px;
    font-size: 1.3rem;
    color: var(--sky);
}

/* RESPONSIVE */
@media (max-width: 768px) {
    .nav {
        display: none;
        position: absolute;
        top: 70px;
        right: 20px;
        background: white;
        padding: 20px;
        border-radius: 12px;
        flex-direction: column;
    }

    .nav a {
        margin: 12px 0;
    }

    .nav.active {
        display: flex;
    }

    .hamburger {
        display: block;
    }
}