/* ---------- Design tokens ---------- */
:root {
    --bg: #ffffff;
    --bg-alt: #f6f7f9;
    --text: #16181d;
    --text-muted: #5b6472;
    --accent: #1f6feb;
    --accent-dark: #1a5fd0;
    --border: #e4e7eb;
    --max-width: 1080px;
    --radius: 10px;
    --shadow: 0 1px 3px rgba(16, 24, 40, 0.06), 0 8px 24px rgba(16, 24, 40, 0.04);
}

/* ---------- Base ---------- */
* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    /* offset anchor jumps for the sticky header */
    scroll-padding-top: 72px;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
    line-height: 1.2;
    letter-spacing: -0.02em;
    margin: 0 0 0.5em;
}

p {
    margin: 0 0 1em;
}

a {
    color: var(--accent);
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

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

.container.narrow {
    max-width: 640px;
}

/* ---------- Header / Nav ---------- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 50;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(12px);
    border-bottom: 1px solid var(--border);
}

.nav {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 64px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-brand {
    font-weight: 700;
    font-size: 1.15rem;
    color: var(--text);
    letter-spacing: -0.02em;
}

.nav-brand:hover {
    text-decoration: none;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 28px;
    margin: 0;
    padding: 0;
}

.nav-links a {
    color: var(--text-muted);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.15s ease;
}

.nav-links a:hover {
    color: var(--text);
    text-decoration: none;
}

/* Mobile toggle (hidden on desktop) */
.nav-toggle,
.nav-toggle-label {
    display: none;
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid transparent;
    transition: background 0.15s ease, border-color 0.15s ease, transform 0.05s ease;
}

.btn:hover {
    text-decoration: none;
}

.btn:active {
    transform: translateY(1px);
}

.btn-primary {
    background: var(--accent);
    color: #fff;
}

.btn-primary:hover {
    background: var(--accent-dark);
}

.btn-ghost {
    background: transparent;
    color: var(--text);
    border-color: var(--border);
}

.btn-ghost:hover {
    border-color: var(--text-muted);
}

/* ---------- Hero ---------- */
.hero {
    padding: 112px 0 96px;
    background:
        radial-gradient(60% 120% at 50% 0%, rgba(31, 111, 235, 0.06), transparent 70%);
}

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

.eyebrow {
    text-transform: uppercase;
    letter-spacing: 0.12em;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent);
    margin-bottom: 16px;
}

.hero h1 {
    font-size: clamp(2.4rem, 6vw, 3.75rem);
    margin-bottom: 20px;
}

.lead {
    font-size: 1.2rem;
    color: var(--text-muted);
    max-width: 560px;
    margin: 0 auto 32px;
}

.hero-actions {
    display: flex;
    gap: 14px;
    justify-content: center;
    flex-wrap: wrap;
}

/* ---------- Sections ---------- */
.section {
    padding: 88px 0;
}

.section-alt {
    background: var(--bg-alt);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.section h2 {
    font-size: clamp(1.8rem, 4vw, 2.4rem);
    text-align: center;
}

.section-intro {
    text-align: center;
    color: var(--text-muted);
    font-size: 1.1rem;
    max-width: 520px;
    margin: 0 auto 48px;
}

/* ---------- Cards ---------- */
.cards {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.card {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    box-shadow: var(--shadow);
}

.card h3 {
    font-size: 1.2rem;
}

.card p {
    color: var(--text-muted);
    margin: 0;
}

/* ---------- About ---------- */
.about-inner {
    max-width: 720px;
}

.about-inner h2 {
    text-align: left;
}

.about-inner p {
    font-size: 1.1rem;
    color: var(--text-muted);
}

/* ---------- Forms ---------- */
.form {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 8px;
    flex: 1;
}

.field-row {
    display: flex;
    gap: 20px;
}

.field label {
    font-size: 0.9rem;
    font-weight: 600;
}

.field input,
.field textarea {
    font: inherit;
    padding: 12px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    background: var(--bg);
    color: var(--text);
    width: 100%;
    transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.field input:focus,
.field textarea:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(31, 111, 235, 0.15);
}

.field textarea {
    resize: vertical;
}

.form .btn {
    align-self: flex-start;
}

.form-note {
    margin: 0;
    font-size: 0.95rem;
    color: var(--text-muted);
    min-height: 1.2em;
}

.form-note.error {
    color: #c0392b;
}

.form-note.success {
    color: #1e7e42;
}

/* ---------- Footer ---------- */
.site-footer {
    border-top: 1px solid var(--border);
    padding: 32px 0;
    background: var(--bg);
}

.footer-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    color: var(--text-muted);
    font-size: 0.9rem;
    flex-wrap: wrap;
    gap: 12px;
}

/* ---------- Responsive ---------- */
@media (max-width: 860px) {
    .cards {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    /* Collapsible mobile nav using a checkbox toggle */
    .nav {
        flex-wrap: wrap;
    }

    .nav-toggle-label {
        display: flex;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
        width: 40px;
        height: 40px;
        cursor: pointer;
    }

    .nav-toggle-label span {
        display: block;
        height: 2px;
        width: 24px;
        background: var(--text);
        border-radius: 2px;
        transition: transform 0.2s ease, opacity 0.2s ease;
    }

    .nav-links {
        flex-basis: 100%;
        flex-direction: column;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.25s ease;
    }

    .nav-toggle:checked ~ .nav-links {
        max-height: 320px;
        padding-bottom: 12px;
    }

    .nav-links li {
        border-top: 1px solid var(--border);
    }

    .nav-links a {
        display: block;
        padding: 14px 0;
    }

    .field-row {
        flex-direction: column;
        gap: 20px;
    }

    .hero {
        padding: 72px 0 64px;
    }

    .section {
        padding: 64px 0;
    }
}