* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: Arial, Helvetica, sans-serif;
    color: #111827;
    background: #ffffff;
    line-height: 1.6;
}

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

.container {
    width: min(1100px, calc(100% - 64px));
    margin: 0 auto;
}

.site-header {
    border-bottom: 1px solid #e5e7eb;
    background: #ffffff;
}

.header-inner {
    width: min(1100px, calc(100% - 64px));
    min-height: 72px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
}

.brand {
    display: inline-flex;
    align-items: baseline;
    gap: 9px;
    letter-spacing: 0.08em;
}

.brand strong {
    font-size: 25px;
    letter-spacing: 0.08em;
}

.brand span {
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 0.08em;
}

.all-tools {
    color: #64748b;
    font-size: 14px;
}

.hero {
    padding: 86px 0 78px;
    background: #ffffff;
}

.eyebrow {
    margin-bottom: 14px;
    color: #5b708a;
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 0.18em;
}

.hero h1 {
    max-width: 900px;
    margin: 0;
    font-size: clamp(48px, 6vw, 72px);
    line-height: 1.04;
    letter-spacing: -0.045em;
}

.hero p {
    max-width: 760px;
    margin: 30px 0 0;
    color: #64748b;
    font-size: 20px;
    line-height: 1.55;
}

.tools-section {
    padding: 82px 0 92px;
    background: #f4fbfd;
    border-top: 1px solid #edf2f5;
}

.tools-section h2 {
    margin: 0;
    font-size: 38px;
    line-height: 1.15;
    letter-spacing: -0.025em;
}

.section-intro {
    margin: 12px 0 38px;
    color: #64748b;
    font-size: 17px;
}

.tool-card {
    position: relative;
    display: block;
    width: min(100%, 650px);
    min-height: 275px;
    padding: 36px 30px 32px;
    border: 1px solid #d9e2e8;
    border-radius: 18px;
    background: #ffffff;
    box-shadow: 0 8px 28px rgba(15, 23, 42, 0.035);
    transition: transform 0.18s ease, box-shadow 0.18s ease, border-color 0.18s ease;
}

.tool-card:hover {
    transform: translateY(-2px);
    border-color: #cbd7df;
    box-shadow: 0 12px 34px rgba(15, 23, 42, 0.07);
}

.tool-number {
    position: absolute;
    top: 28px;
    right: 28px;
    color: #718096;
    font-size: 13px;
}

.tool-icon {
    margin-bottom: 20px;
    font-size: 30px;
}

.tool-card h3 {
    max-width: 500px;
    margin: 0 0 12px;
    font-size: 26px;
    line-height: 1.2;
}

.tool-card p {
    max-width: 560px;
    margin: 0 0 24px;
    color: #64748b;
    font-size: 15px;
}

.tool-link {
    font-weight: 700;
    font-size: 15px;
}

.about-section {
    padding: 90px 0;
    background: #ffffff;
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 70px;
}

.about-section h2 {
    max-width: 560px;
    margin: 0 0 20px;
    font-size: 38px;
    line-height: 1.12;
    letter-spacing: -0.025em;
}

.about-section p {
    max-width: 590px;
    margin: 0;
    color: #64748b;
    font-size: 17px;
}

.principles {
    border-top: 1px solid #dfe6eb;
}

.principle {
    display: flex;
    flex-direction: column;
    gap: 7px;
    padding: 24px 0;
    border-bottom: 1px solid #dfe6eb;
}

.principle strong {
    font-size: 18px;
}

.principle span {
    color: #64748b;
    font-size: 15px;
}

.site-footer {
    padding: 28px 0;
    background: #111827;
    color: #ffffff;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 30px;
    font-size: 13px;
}

.footer-inner span {
    color: #d1d5db;
}

@media (max-width: 760px) {
    .container,
    .header-inner {
        width: min(100% - 36px, 1100px);
    }

    .hero {
        padding: 62px 0 60px;
    }

    .hero h1 {
        font-size: 46px;
    }

    .hero p {
        font-size: 18px;
    }

    .tools-section,
    .about-section {
        padding: 62px 0;
    }

    .about-grid {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .about-section h2 {
        font-size: 32px;
    }

    .footer-inner {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
}

@media (max-width: 520px) {
    .header-inner {
        min-height: 64px;
    }

    .brand strong {
        font-size: 22px;
    }

    .brand span {
        font-size: 12px;
    }

    .all-tools {
        font-size: 12px;
    }

    .hero h1 {
        font-size: 39px;
    }

    .tool-card {
        padding: 30px 24px;
    }
}