:root {
    --primary: #ff0033;
    --primary-dark: #d9002b;
    --dark: #111827;
    --text: #1f2937;
    --muted: #6b7280;
    --background: #f5f7fb;
}

body {
    background: var(--background);
    color: var(--text);
    font-family:
        system-ui,
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;
}

.hero {
    padding: 80px 20px 120px;
    background:
        linear-gradient(
            135deg,
            #111827 0%,
            #1f2937 100%
        );
    color: #ffffff;
}

.hero-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 18px;
    background: rgba(255, 255, 255, .08);
    font-size: 28px;
}

.hero h1 {
    max-width: 850px;
    margin: 0 auto;
    font-size: clamp(
        2rem,
        5vw,
        3.5rem
    );
    font-weight: 800;
    line-height: 1.1;
}

.hero p {
    max-width: 720px;
    margin: 22px auto 0;
    color: #d1d5db;
}

.converter-card {
    max-width: 950px;
    margin: -65px auto 0;
    position: relative;
    z-index: 2;
    padding: 35px;
    background: #ffffff;
    border-radius: 20px;
    box-shadow:
        0 20px 60px
        rgba(0, 0, 0, .12);
}

#video_url {
    min-height: 58px;
}

#analyzeButton {
    min-height: 58px;
    background: var(--primary);
    border-color: var(--primary);
    font-weight: 700;
}

#analyzeButton:hover {
    background: var(--primary-dark);
    border-color: var(--primary-dark);
}

.result-card {
    animation: fadeIn .25s ease;
}

.video-thumbnail {
    width: 100%;
    max-width: 340px;
    aspect-ratio: 16 / 9;
    object-fit: cover;
    border-radius: 14px;
    box-shadow:
        0 8px 30px
        rgba(0, 0, 0, .10);
}

.format-card {
    min-height: 115px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    padding: 18px;
    border: 2px solid #e5e7eb;
    border-radius: 14px;
    background: #ffffff;
    cursor: pointer;
    transition:
        border-color .2s ease,
        background .2s ease,
        transform .2s ease;
}

.format-card:hover {
    border-color: var(--primary);
    background: #fff7f9;
    transform: translateY(-2px);
}

.format-card:has(input:checked) {
    border-color: var(--primary);
    background: #fff2f5;
}

.format-card input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.format-title {
    font-weight: 800;
    font-size: 1.05rem;
}

.format-title i {
    margin-right: 5px;
}

.format-description {
    color: var(--muted);
    font-size: .9rem;
}

#downloadButton {
    min-height: 58px;
    border-radius: 12px;
    font-weight: 700;
}

.seo-content {
    max-width: 950px;
    margin: 80px auto;
}

.seo-content h2 {
    margin-top: 50px;
    margin-bottom: 18px;
    font-weight: 800;
}

.seo-content p {
    color: #4b5563;
    line-height: 1.8;
}

.faq-item {
    margin-bottom: 15px;
    padding: 24px;
    background: #ffffff;
    border-radius: 14px;
    box-shadow:
        0 5px 20px
        rgba(0, 0, 0, .04);
}

footer {
    background: var(--dark);
    color: #9ca3af;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(8px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@media (max-width: 767px) {
    .hero {
        padding: 60px 20px 100px;
    }

    .converter-card {
        margin-top: -55px;
        padding: 22px;
        border-radius: 16px;
    }

    #video_url,
    #analyzeButton {
        min-height: 52px;
    }

    #analyzeButton {
        margin-top: 8px;
        width: 100%;
    }
}