:root {
    --bg-top: #01030a;
    --bg-mid: #06111f;
    --bg-bottom: #000104;

    --card: #0b1220;
    --card-alt: #0f1a2d;
    --surface: #101a2b;
    --surface-2: #182438;

    --blue: #2563eb;
    --blue-bright: #3b82f6;
    --blue-glow: #60a5fa;
    --blue-soft: #93c5fd;

    --text-primary: #ffffff;
    --text-secondary: #a8b6cc;
    --text-muted: #6f819a;

    --track: #243247;

    --border: rgba(96, 165, 250, 0.20);
    --border-strong: rgba(96, 165, 250, 0.42);

    --container: 1180px;
}


/* Base */

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

html {
    scroll-behavior: smooth;
}

body {
    min-height: 100vh;
    overflow-x: hidden;

    background:
        radial-gradient(
            circle at 8% 8%,
            rgba(37, 99, 235, 0.20),
            transparent 30%
        ),
        radial-gradient(
            circle at 90% 38%,
            rgba(59, 130, 246, 0.12),
            transparent 34%
        ),
        linear-gradient(
            180deg,
            var(--bg-top),
            var(--bg-mid) 48%,
            var(--bg-bottom)
        );

    color: var(--text-primary);

    font-family:
        Inter,
        system-ui,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;

    line-height: 1.6;
}

img {
    max-width: 100%;
}

a {
    color: inherit;
    text-decoration: none;
}

.container {
    width: min(calc(100% - 40px), var(--container));
    margin-inline: auto;
}

section {
    scroll-margin-top: 84px;
}


/* Header */

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;

    background: rgba(1, 3, 10, 0.88);
    border-bottom: 1px solid rgba(96, 165, 250, 0.12);

    backdrop-filter: blur(18px);
}

.header-content {
    min-height: 78px;

    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 28px;
}

.brand {
    display: flex;
    align-items: center;
    gap: 8px;
}

.brand-logo {
    width: 62px;
    height: 62px;

    display: block;
    object-fit: contain;
}

.brand-text {
    display: flex;
    flex-direction: column;

    line-height: 1.15;
}

.brand-text strong {
    font-size: 20px;
}

.brand-text span {
    margin-top: 4px;

    color: var(--text-muted);
    font-size: 12px;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 30px;
}

.main-nav a {
    position: relative;

    color: var(--text-secondary);
    font-size: 14px;

    transition:
        color 180ms ease,
        transform 180ms ease;
}

.main-nav a:hover {
    color: var(--blue-soft);
    transform: translateY(-1px);
}

.main-nav a::after {
    content: "";

    position: absolute;
    left: 0;
    right: 0;
    bottom: -8px;

    height: 2px;

    border-radius: 10px;
    background: var(--blue-glow);

    transform: scaleX(0);

    transition: transform 180ms ease;
}

.main-nav a:hover::after {
    transform: scaleX(1);
}


/* Elementos generales */

.eyebrow {
    display: inline-flex;
    align-items: center;

    color: var(--blue-glow);

    font-size: 12px;
    font-weight: 750;
    letter-spacing: 0.13em;
    text-transform: uppercase;
}

.button {
    min-height: 48px;

    display: inline-flex;
    align-items: center;
    justify-content: center;

    padding: 0 21px;

    border-radius: 15px;

    font-size: 14px;
    font-weight: 700;

    transition:
        transform 180ms ease,
        border-color 180ms ease,
        background 180ms ease;
}

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

.button-primary {
    background:
        linear-gradient(
            135deg,
            var(--blue),
            var(--blue-bright)
        );

    color: white;

    box-shadow:
        0 16px 38px rgba(37, 99, 235, 0.30);
}

.button-secondary {
    border: 1px solid var(--border-strong);

    background: rgba(16, 26, 43, 0.72);
    color: var(--blue-soft);
}

.button-secondary:hover {
    background: var(--surface-2);
}


/* Inicio */

.hero {
    padding: 54px 0 66px;
}

.hero-content {
    display: grid;
    grid-template-columns: minmax(0, 0.92fr) minmax(420px, 1.08fr);
    align-items: center;
    gap: 62px;
}

.hero h1 {
    max-width: 650px;

    margin-top: 15px;

    font-size: clamp(46px, 5.5vw, 72px);
    line-height: 1;
    letter-spacing: -0.052em;
}

.hero h1 span {
    color: var(--blue-glow);

    text-shadow:
        0 0 34px rgba(96, 165, 250, 0.35);
}

.hero-description {
    max-width: 590px;

    margin-top: 23px;

    color: var(--text-secondary);

    font-size: 17px;
    line-height: 1.75;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 13px;

    margin-top: 27px;
}

.privacy-note {
    display: flex;
    align-items: center;
    gap: 10px;

    margin-top: 19px;

    color: var(--text-muted);
    font-size: 13px;
}

.privacy-note span {
    width: 25px;
    height: 25px;

    display: grid;
    place-items: center;

    border-radius: 50%;
    border: 1px solid rgba(96, 165, 250, 0.35);

    background: rgba(37, 99, 235, 0.12);
    color: var(--blue-glow);
}


/* Vista previa del reproductor */

.hero-preview {
    position: relative;
}

.hero-preview::before {
    content: "";

    position: absolute;
    inset: 10% 6%;

    border-radius: 50%;

    background: rgba(37, 99, 235, 0.22);

    filter: blur(85px);
}

.app-window {
    position: relative;

    min-height: 480px;

    padding: 23px;

    border-radius: 29px;
    border: 1px solid var(--border-strong);

    background:
        radial-gradient(
            circle at 18% 10%,
            rgba(37, 99, 235, 0.15),
            transparent 30%
        ),
        rgba(11, 18, 32, 0.94);

    box-shadow:
        0 34px 80px rgba(0, 0, 0, 0.42),
        inset 0 1px 0 rgba(255, 255, 255, 0.03);
}

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

.app-window-header > div:first-child {
    display: flex;
    flex-direction: column;
}

.app-window-header strong {
    font-size: 23px;
}

.app-window-header span {
    margin-top: 2px;

    color: var(--blue-soft);
    font-size: 12px;
}

.menu-button {
    width: 42px;
    height: 42px;

    display: grid;
    place-items: center;

    border-radius: 14px;
    border: 1px solid var(--border);

    background: var(--surface);
    color: var(--blue-glow);
}

.search-preview {
    margin-top: 19px;

    padding: 13px 17px;

    border-radius: 17px;

    background: var(--surface);

    color: var(--text-muted);
    font-size: 13px;
}

.reading-card {
    display: grid;
    grid-template-columns: 100px 1fr;
    align-items: center;
    gap: 19px;

    margin-top: 18px;
    padding: 18px;

    border-radius: 22px;
    border: 1px solid var(--border);

    background: rgba(15, 26, 45, 0.94);
}

.book-cover {
    height: 130px;

    display: grid;
    place-items: center;

    border-radius: 18px;
    border: 1px solid rgba(96, 165, 250, 0.20);

    background:
        radial-gradient(
            circle at 50% 25%,
            rgba(96, 165, 250, 0.24),
            transparent 55%
        ),
        linear-gradient(
            180deg,
            var(--card-alt),
            var(--bg-top)
        );

    color: var(--blue-soft);
    font-size: 15px;
    font-weight: 700;
}

.reading-info {
    min-width: 0;
}

.reading-label {
    color: var(--blue-glow);

    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.reading-info h2 {
    margin-top: 7px;

    font-size: 23px;
    line-height: 1.2;
}

.reading-info p {
    margin-top: 6px;

    color: var(--text-secondary);
    font-size: 12px;
}

.progress-track {
    height: 7px;

    margin-top: 17px;

    overflow: hidden;

    border-radius: 999px;

    background: var(--track);
}

.progress-value {
    width: 29%;
    height: 100%;

    border-radius: inherit;

    background:
        linear-gradient(
            90deg,
            var(--blue),
            var(--blue-glow)
        );
}

.player-preview {
    display: flex;
    align-items: center;
    justify-content: space-between;

    margin-top: 23px;
    padding-inline: 7px;
}

.player-preview > span {
    width: 44px;
    height: 44px;

    display: grid;
    place-items: center;

    border-radius: 50%;

    background: var(--surface-2);
    color: var(--blue-soft);

    font-size: 20px;
}

.player-preview .play-button {
    width: 72px;
    height: 72px;

    background:
        linear-gradient(
            135deg,
            var(--blue),
            var(--blue-bright)
        );

    color: white;
    font-size: 26px;

    box-shadow:
        0 18px 42px rgba(37, 99, 235, 0.38);
}

.player-options {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 7px;

    margin-top: 22px;
}

.player-options span {
    min-height: 40px;

    display: grid;
    place-items: center;

    padding: 7px;

    border-radius: 14px;

    background: var(--surface-2);

    color: var(--text-secondary);
    font-size: 11px;
}


/* Funciones */

.features {
    padding: 22px 0 72px;
}

.section-heading {
    max-width: 730px;

    margin: 0 auto 34px;

    text-align: center;
}

.section-heading h2,
.app-copy h2 {
    margin-top: 10px;

    font-size: clamp(32px, 3.7vw, 45px);
    line-height: 1.13;
    letter-spacing: -0.035em;
}

.section-heading p,
.app-copy > p {
    margin-top: 13px;

    color: var(--text-secondary);
    font-size: 15px;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.feature-card {
    min-height: 190px;

    padding: 22px;

    border-radius: 21px;
    border: 1px solid var(--border);

    background:
        linear-gradient(
            145deg,
            rgba(15, 26, 45, 0.96),
            rgba(11, 18, 32, 0.96)
        );

    transition:
        transform 180ms ease,
        border-color 180ms ease;
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--border-strong);
}

.feature-icon {
    width: 45px;
    height: 45px;

    display: grid;
    place-items: center;

    border-radius: 15px;
    border: 1px solid rgba(96, 165, 250, 0.28);

    background: rgba(37, 99, 235, 0.14);
    color: var(--blue-glow);

    font-size: 21px;
    font-weight: 700;
}

.feature-icon-text {
    font-size: 15px;
}

.feature-card h3 {
    margin-top: 16px;

    font-size: 18px;
}

.feature-card p {
    margin-top: 7px;

    color: var(--text-secondary);

    font-size: 13px;
    line-height: 1.65;
}


/* Aplicación */

.app-section {
    padding: 72px 0 78px;

    border-top: 1px solid rgba(96, 165, 250, 0.10);

    background:
        radial-gradient(
            circle at 80% 40%,
            rgba(37, 99, 235, 0.16),
            transparent 35%
        ),
        rgba(6, 17, 31, 0.45);
}

.app-section-content {
    display: grid;
    grid-template-columns: 0.90fr 1.10fr;
    align-items: center;
    gap: 58px;
}

.app-copy > p {
    max-width: 620px;
}

.app-list {
    display: grid;
    gap: 10px;

    margin-top: 23px;

    list-style: none;
}

.app-list li {
    position: relative;

    padding-left: 28px;

    color: var(--text-secondary);
    font-size: 15px;
}

.app-list li::before {
    content: "✓";

    position: absolute;
    left: 0;
    top: 0;

    color: var(--blue-glow);
    font-weight: 800;
}


/* Capturas reales */

.screens-preview {
    display: grid;
    grid-template-columns: 0.92fr 1.08fr 0.92fr;
    align-items: center;
    gap: 15px;

    padding: 30px 10px;
}

.screen-card {
    position: relative;

    width: 100%;
    aspect-ratio: 9 / 19.5;

    overflow: hidden;

    border-radius: 24px;
    border: 1px solid var(--border-strong);

    background: var(--card);

    box-shadow:
        0 24px 48px rgba(0, 0, 0, 0.32),
        0 0 28px rgba(37, 99, 235, 0.08);

    transition:
        transform 180ms ease,
        border-color 180ms ease,
        box-shadow 180ms ease;
}

.screen-card:first-child,
.screen-card:last-child {
    transform: scale(0.94);
}

.screen-card-center {
    z-index: 2;

    transform: scale(1.06);

    border-color: rgba(96, 165, 250, 0.72);

    box-shadow:
        0 30px 65px rgba(0, 0, 0, 0.42),
        0 0 38px rgba(37, 99, 235, 0.22);
}

.screen-card img {
    width: 100%;
    height: 100%;

    display: block;

    object-fit: cover;
    object-position: top center;
}


/* Footer */

.site-footer {
    border-top: 1px solid rgba(96, 165, 250, 0.10);

    background: rgba(0, 1, 4, 0.82);
}

.footer-content {
    min-height: 108px;

    display: grid;
    grid-template-columns: 1fr auto 1fr;
    align-items: center;
    gap: 30px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 9px;

    justify-self: start;
}

.footer-brand img {
    width: 48px;
    height: 48px;

    display: block;
    object-fit: contain;
}

.footer-brand > div {
    display: flex;
    flex-direction: column;
}

.footer-brand strong {
    font-size: 17px;
}

.footer-brand span {
    margin-top: 2px;

    color: var(--text-muted);
    font-size: 10px;
}

.copyright {
    justify-self: center;

    color: var(--text-muted);

    font-size: 11px;
    text-align: center;
    white-space: nowrap;
}

.footer-privacy {
    justify-self: end;

    color: var(--text-secondary);
    font-size: 12px;

    transition: color 180ms ease;
}

.footer-privacy:hover {
    color: var(--blue-soft);
}


/* Tablets */

@media (max-width: 1000px) {
    .hero-content,
    .app-section-content {
        grid-template-columns: 1fr;
    }

    .hero-copy {
        text-align: center;
    }

    .hero-description {
        margin-inline: auto;
    }

    .hero-actions,
    .privacy-note {
        justify-content: center;
    }

    .hero-preview {
        width: min(100%, 620px);
        margin-inline: auto;
    }

    .feature-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .app-section-content {
        gap: 42px;
    }

    .app-copy {
        text-align: center;
    }

    .app-copy > p {
        margin-inline: auto;
    }

    .app-list {
        width: fit-content;
        margin-inline: auto;
        text-align: left;
    }

    .screens-preview {
        width: min(100%, 680px);
        margin-inline: auto;
    }
}


/* Móvil */

@media (max-width: 760px) {
    .main-nav {
        display: none;
    }

    .header-content {
        min-height: 70px;
    }

    .brand-logo {
        width: 55px;
        height: 55px;
    }

    .hero {
        padding: 46px 0 58px;
    }

    .hero h1 {
        font-size: 48px;
    }

    .app-window {
        min-height: auto;

        padding: 18px;

        border-radius: 24px;
    }

    .reading-card {
        grid-template-columns: 82px 1fr;
        gap: 15px;

        padding: 15px;
    }

    .book-cover {
        height: 108px;
    }

    .reading-info h2 {
        font-size: 20px;
    }

    .player-preview > span {
        width: 39px;
        height: 39px;
    }

    .player-preview .play-button {
        width: 65px;
        height: 65px;
    }

    .features {
        padding: 56px 0 62px;
    }

    .feature-grid {
        grid-template-columns: 1fr;
    }

    .feature-card {
        min-height: auto;
    }

    .app-section {
        padding: 60px 0;
    }

    .screens-preview {
        grid-template-columns: repeat(3, minmax(0, 1fr));
        gap: 7px;

        padding: 20px 3px;
    }

    .screen-card {
        border-radius: 14px;
    }

    .screen-card:first-child,
    .screen-card:last-child {
        transform: scale(0.96);
    }

    .screen-card-center {
        transform: scale(1.05);
    }

    .footer-content {
        min-height: auto;

        grid-template-columns: 1fr;
        justify-items: center;
        gap: 15px;

        padding: 25px 0;
    }

    .footer-brand,
    .copyright,
    .footer-privacy {
        justify-self: center;
    }
}


/* Móvil pequeño */

@media (max-width: 480px) {
    .container {
        width: min(calc(100% - 28px), var(--container));
    }

    .hero h1 {
        font-size: 41px;
    }

    .hero-description {
        font-size: 15px;
    }

    .hero-actions {
        flex-direction: column;
    }

    .button {
        width: 100%;
    }

    .reading-card {
        grid-template-columns: 1fr;

        text-align: center;
    }

    .book-cover {
        width: 88px;
        height: 118px;

        margin-inline: auto;
    }

    .player-options {
        grid-template-columns: repeat(2, 1fr);
    }

    .player-preview {
        padding-inline: 0;
    }

    .player-preview > span {
        width: 35px;
        height: 35px;
    }

    .player-preview .play-button {
        width: 59px;
        height: 59px;
    }

    .section-heading h2,
    .app-copy h2 {
        font-size: 32px;
    }

    .screens-preview {
        gap: 4px;
        padding: 16px 0;
    }

    .screen-card {
        border-radius: 10px;
    }

    .screen-card:first-child,
    .screen-card:last-child {
        transform: scale(0.97);
    }

    .screen-card-center {
        transform: scale(1.04);
    }
}