/* ─── Reset & Base ─── */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: #f5f5f7;
    color: #1d1d1f;
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 720px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ─── Header ─── */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(245, 245, 247, 0.72);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.08);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 56px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: #1d1d1f;
}

.logo-icon {
    width: 32px;
    height: 32px;
    background: linear-gradient(135deg, #0A84FF, #5E5CE6);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 700;
    font-size: 16px;
}

.logo-text {
    font-weight: 600;
    font-size: 15px;
    letter-spacing: -0.01em;
}

.nav {
    display: flex;
    align-items: center;
    gap: 20px;
}

.nav-link {
    text-decoration: none;
    color: #0A84FF;
    font-size: 14px;
    font-weight: 500;
    transition: opacity 0.2s;
}

.nav-link:hover {
    opacity: 0.7;
}

.lang-btn {
    background: #0A84FF;
    color: white;
    border: none;
    padding: 5px 12px;
    border-radius: 14px;
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
    letter-spacing: 0.02em;
}

.lang-btn:hover {
    background: #0071E3;
    transform: scale(1.05);
}

.lang-btn:active {
    transform: scale(0.97);
}

/* ─── Hero ─── */
.hero {
    padding: 64px 0 40px;
    text-align: center;
}

.hero h1 {
    font-size: clamp(28px, 5vw, 40px);
    font-weight: 700;
    letter-spacing: -0.025em;
    color: #1d1d1f;
    line-height: 1.2;
}

.hero-sub {
    margin-top: 12px;
    font-size: 17px;
    color: #86868b;
    font-weight: 400;
}

/* ─── Cards ─── */
.card {
    background: white;
    border-radius: 20px;
    padding: 40px 36px;
    margin-bottom: 24px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.04), 0 4px 16px rgba(0, 0, 0, 0.04);
    border: 1px solid rgba(0, 0, 0, 0.04);
}

.card h2 {
    font-size: 26px;
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 4px;
}

.card .meta {
    font-size: 13px;
    color: #86868b;
    margin-bottom: 28px;
}

.card h3 {
    font-size: 17px;
    font-weight: 600;
    margin-top: 28px;
    margin-bottom: 8px;
    color: #1d1d1f;
}

.card p {
    font-size: 15px;
    color: #424245;
    margin-bottom: 12px;
}

.card ul {
    padding-left: 20px;
    margin-bottom: 12px;
}

.card ul li {
    font-size: 15px;
    color: #424245;
    margin-bottom: 6px;
}

.email-link {
    color: #0A84FF;
    text-decoration: none;
    font-weight: 500;
}

.email-link:hover {
    text-decoration: underline;
}

.response-time {
    font-size: 14px;
    color: #86868b;
    font-style: italic;
    margin-top: 8px;
}

/* ─── FAQ ─── */
.faq {
    margin: 16px 0 28px;
}

details {
    border: 1px solid rgba(0, 0, 0, 0.08);
    border-radius: 12px;
    margin-bottom: 8px;
    overflow: hidden;
    transition: all 0.2s;
}

details[open] {
    background: #fafafa;
}

summary {
    padding: 14px 18px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    list-style: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    user-select: none;
    transition: background 0.15s;
}

summary:hover {
    background: rgba(0, 0, 0, 0.02);
}

summary::-webkit-details-marker {
    display: none;
}

summary::after {
    content: '+';
    font-size: 20px;
    font-weight: 300;
    color: #86868b;
    transition: transform 0.2s;
    flex-shrink: 0;
    margin-left: 12px;
}

details[open] summary::after {
    content: '−';
}

details p {
    padding: 0 18px 14px;
    font-size: 14px;
    color: #636366;
    line-height: 1.6;
}

/* ─── Contact Box ─── */
.contact-box {
    background: linear-gradient(135deg, #f0f5ff, #f5f0ff);
    border-radius: 16px;
    padding: 28px;
    text-align: center;
    margin-top: 24px;
    border: 1px solid rgba(10, 132, 255, 0.1);
}

.contact-box h3 {
    margin-top: 0;
}

.contact-btn {
    display: inline-block;
    background: linear-gradient(135deg, #0A84FF, #5E5CE6);
    color: white;
    text-decoration: none;
    padding: 12px 28px;
    border-radius: 24px;
    font-size: 15px;
    font-weight: 600;
    margin: 12px 0;
    transition: all 0.2s;
    box-shadow: 0 2px 8px rgba(10, 132, 255, 0.3);
}

.contact-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(10, 132, 255, 0.4);
}

.contact-btn:active {
    transform: translateY(0);
}

/* ─── Footer ─── */
.footer {
    margin-top: 32px;
    padding: 28px 0;
    border-top: 1px solid rgba(0, 0, 0, 0.08);
    text-align: center;
}

.footer-inner {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
}

.footer-links {
    display: flex;
    gap: 12px;
    align-items: center;
}

.footer-links a {
    color: #0A84FF;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
}

.footer-links a:hover {
    text-decoration: underline;
}

.footer-links .divider {
    color: #d2d2d7;
    font-size: 14px;
}

.copyright {
    font-size: 13px;
    color: #86868b;
}

/* ─── Responsive ─── */
@media (max-width: 600px) {
    .card {
        padding: 28px 20px;
        border-radius: 16px;
    }

    .hero {
        padding: 48px 0 28px;
    }

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

    .logo-text {
        font-size: 14px;
    }

    .nav {
        gap: 14px;
    }

    .nav-link {
        font-size: 13px;
    }

    .contact-box {
        padding: 20px;
    }
}

/* ─── Animation ─── */
@media (prefers-reduced-motion: no-preference) {
    .card {
        animation: fadeUp 0.5s ease-out both;
    }

    .card:nth-child(2) {
        animation-delay: 0.1s;
    }

    @keyframes fadeUp {
        from {
            opacity: 0;
            transform: translateY(16px);
        }
        to {
            opacity: 1;
            transform: translateY(0);
        }
    }
}

/* ─── Dark Mode ─── */
@media (prefers-color-scheme: dark) {
    body {
        background: #000;
        color: #f5f5f7;
    }

    .header {
        background: rgba(0, 0, 0, 0.72);
        border-bottom-color: rgba(255, 255, 255, 0.08);
    }

    .logo {
        color: #f5f5f7;
    }

    .hero h1 {
        color: #f5f5f7;
    }

    .card {
        background: #1c1c1e;
        border-color: rgba(255, 255, 255, 0.06);
        box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
    }

    .card h3 {
        color: #f5f5f7;
    }

    .card p,
    .card ul li {
        color: #a1a1a6;
    }

    details {
        border-color: rgba(255, 255, 255, 0.1);
    }

    details[open] {
        background: #2c2c2e;
    }

    summary:hover {
        background: rgba(255, 255, 255, 0.04);
    }

    details p {
        color: #98989d;
    }

    .contact-box {
        background: linear-gradient(135deg, #1a1a2e, #16213e);
        border-color: rgba(10, 132, 255, 0.2);
    }

    .footer {
        border-top-color: rgba(255, 255, 255, 0.08);
    }
}