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

:root {
    --bg: #07070a;
    --bg-secondary: #0d0d12;
    --text: #f5f7ff;
    --text-muted: #a7adbf;
    --border: rgba(255, 255, 255, 0.08);
}

body {
    font-family: Arial, Helvetica, sans-serif;
    background:
        radial-gradient(circle at top left, rgba(98, 70, 255, 0.18), transparent 28%),
        radial-gradient(circle at 80% 20%, rgba(0, 153, 255, 0.14), transparent 24%),
        linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px),
        var(--bg);
    background-size:
        auto,
        auto,
        32px 32px,
        32px 32px,
        auto;
    color: var(--text);
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    padding: 20px 0;

    z-index: 1000;

    background: transparent;
    border-bottom: 1px solid transparent;

    transition: background 0.3s ease,
                backdrop-filter 0.3s ease,
                border 0.3s ease;
}

header.scrolled {
    backdrop-filter: blur(10px);
    background: rgba(10, 10, 18, 0.4);
    border-bottom: 1px solid var(--border);
}

.logo {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 0.04em;
}

.hero {
    min-height: calc(100vh - 80px);
    display: flex;
    align-items: center;
    padding-top: 120px;
}

.hero h1 {
    font-size: 72px;
    line-height: 1;
    letter-spacing: -0.04em;
    max-width: 900px;
    margin-bottom: 24px;
}

.hero h1 {
    font-size: 72px;
    line-height: 1.05;
    letter-spacing: -0.01em;
    max-width: 900px;
    margin-bottom: 24px;
}

.footer {
    border-top: 1px solid var(--border);
    padding: 24px 0;
    color: var(--text-muted);
}

html, body {
    height: 100%;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: Arial, Helvetica, sans-serif;

    background:
        radial-gradient(circle at top left, rgba(98, 70, 255, 0.18), transparent 28%),
        radial-gradient(circle at 80% 20%, rgba(0, 153, 255, 0.14), transparent 24%),
        linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px),
        var(--bg);

    background-size:
        auto,
        auto,
        32px 32px,
        32px 32px,
        auto;

    background-attachment: fixed;

    color: var(--text);
}

main {
    flex: 1;
}

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

.nav {
    display: flex;
    gap: 28px;
}

.nav-link {
    text-decoration: none;
    color: var(--text-muted);
    font-size: 14px;
    letter-spacing: 0.04em;
    transition: color 0.2s ease;
}

.nav-link:hover {
    color: var(--text);
}

.nav-link {
    position: relative;
}

.nav-link.active {
    color: var(--text);
    text-shadow: 0 0 12px rgba(120, 90, 255, 0.45);
}

.header-button {
    text-decoration: none;
    font-size: 14px;
    padding: 10px 18px;
    border-radius: 10px;

    background: linear-gradient(
        135deg,
        #7a7cff,
        #a066ff
    );

    color: white;

    transition: background 0.4s ease,
                box-shadow 0.4s ease;
}

.header-button:hover {
    background: linear-gradient(
        135deg,
        #8f90ff,
        #b37aff
    );

    box-shadow: 0 0 16px rgba(140, 110, 255, 0.6);
}


/* Style for sections */
.section {
    padding: 140px 0;
}

.section h2 {
    font-size: 42px;
    margin-bottom: 20px;
    letter-spacing: -0.01em;
}

.section p {
    font-size: 18px;
    line-height: 1.6;
    color: var(--text-muted);
    max-width: 700px;
}

/* grid for About */
.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 80px;
    margin-top: 60px;
}

.about-col h3 {
    font-size: 22px;
    margin-top: 16px;
    margin-bottom: 12px;
}

.about-icon {
    font-size: 28px;
    opacity: 0.9;
}

.about-col p {
    max-width: 420px;
}

.about-col {
    padding: 24px;
    border-radius: 12px;
    transition: background 0.3s ease, box-shadow 0.3s ease;
}

.about-col:hover {
    background: rgba(255, 255, 255, 0.02);

    box-shadow:
        0 0 40px rgba(120, 80, 255, 0.15),
        0 0 80px rgba(0, 120, 255, 0.08);
}

.about-svg {
    width: 108px;
    height: 108px;
    color: #9aa3ff;
}

.about-col:hover .about-svg {
    color: #b7bfff;
    filter: drop-shadow(0 0 6px rgba(120, 90, 255, 0.6));
}

/* Concept */
.concept-text {
    max-width: 760px;
    margin-top: 20px;
    margin-bottom: 60px;
    font-size: 18px;
    line-height: 1.7;
    color: var(--text-muted);
}

.concept-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.concept-card {
    padding: 28px;
    border-radius: 14px;

    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border);

    transition: box-shadow 0.3s ease,
                background 0.3s ease,
                border 0.3s ease;
}

.concept-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.concept-card p {
    font-size: 16px;
    color: var(--text-muted);
    line-height: 1.6;
}

.concept-card:hover {
    background: rgba(255, 255, 255, 0.03);

    box-shadow:
        0 0 40px rgba(120, 80, 255, 0.12),
        0 0 80px rgba(0, 120, 255, 0.06);

    border-color: rgba(150, 120, 255, 0.4);
}

/* user-stories */

.user-stories-text {
    max-width: 760px;
    margin-top: 20px;
    margin-bottom: 60px;
    font-size: 18px;
    line-height: 1.7;
    color: var(--text-muted);
}

.user-stories-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.user-story-card {
    padding: 28px;
    border-radius: 14px;

    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border);

    transition: box-shadow 0.3s ease,
                background 0.3s ease,
                border 0.3s ease;
}

.user-story-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.user-story-card p {
    font-size: 16px;
    color: var(--text-muted);
    line-height: 1.6;
}

.user-story-card:hover {
    background: rgba(255, 255, 255, 0.03);

    box-shadow:
        0 0 40px rgba(120, 80, 255, 0.12),
        0 0 80px rgba(0, 120, 255, 0.06);

    border-color: rgba(150, 120, 255, 0.4);
}

/* Contact */
.contact-text {
    max-width: 600px;
    margin-top: 20px;
    margin-bottom: 40px;
    font-size: 18px;
    line-height: 1.7;
    color: var(--text-muted);
}

.contact-actions {
    display: flex;
    justify-content: flex-start;
}

.contact-button {
    display: inline-block;
    padding: 14px 28px;
    border-radius: 10px;

    background: linear-gradient(
        135deg,
        rgba(120, 80, 255, 0.9),
        rgba(0, 120, 255, 0.9)
    );

    color: white;
    text-decoration: none;
    font-weight: 500;

    transition: background 0.4s ease,
                box-shadow 0.4s ease;
}

.contact-button:hover {
    background: linear-gradient(
        135deg,
        rgba(140, 100, 255, 1),
        rgba(0, 140, 255, 1)
    );

    box-shadow:
        0 0 30px rgba(120, 80, 255, 0.4),
        0 0 60px rgba(0, 120, 255, 0.25);
}

/* Footer */

.footer {
    margin-top: 80px;
    border-top: 1px solid var(--border);
    background: rgba(0, 0, 0, 0.4);
}

.footer-inner {
    display: flex;
    justify-content: left;
    align-items: center;

    height: 80px;

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