* {
    box-sizing: border-box;
}

:root {
    --bg: #f4f7fb;
    --card-bg: rgba(255, 255, 255, 0.82);
    --card-border: rgba(255, 255, 255, 0.7);
    --text: #0f172a;
    --muted: #64748b;
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --soft: #eef2ff;
    --shadow: 0 20px 50px rgba(15, 23, 42, 0.10);
    --radius-xl: 28px;
    --radius-lg: 18px;
    --radius-md: 14px;
}

html,
body {
    margin: 0;
    padding: 0;
    font-family: Inter, Arial, sans-serif;
    background:
        radial-gradient(circle at top left, #e0e7ff 0%, transparent 30%),
        radial-gradient(circle at bottom right, #dbeafe 0%, transparent 28%),
        var(--bg);
    color: var(--text);
}

body {
    min-height: 100vh;
    padding: 32px 16px;
}

.tabs-section {
    width: 100%;
}

.tabs-container {
    max-width: 920px;
    margin: 0 auto;
}

.tabs-header {
    text-align: center;
    margin-bottom: 28px;
}

.tabs-label {
    margin: 0 0 10px;
    color: var(--primary);
    font-size: 14px;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.12em;
}

.tabs-title {
    margin: 0;
    font-size: clamp(32px, 5vw, 52px);
    line-height: 1.05;
    font-weight: 800;
}

.tabs-subtitle {
    max-width: 640px;
    margin: 14px auto 0;
    color: var(--muted);
    font-size: 17px;
    line-height: 1.6;
}

.tabs {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    backdrop-filter: blur(14px);
    border-radius: var(--radius-xl);
    padding: 20px;
    box-shadow: var(--shadow);
}

.tabs-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    padding: 8px;
    background: #f8fafc;
    border-radius: 20px;
    margin-bottom: 22px;
    border: 1px solid #e2e8f0;
}

.tab-btn {
    appearance: none;
    border: none;
    background: transparent;
    color: var(--muted);
    padding: 14px 20px;
    border-radius: 14px;
    font-size: 15px;
    font-weight: 700;
    cursor: pointer;
    transition:
        background 0.25s ease,
        color 0.25s ease,
        transform 0.2s ease,
        box-shadow 0.25s ease;
}

.tab-btn:hover {
    background: #ffffff;
    color: var(--text);
    transform: translateY(-1px);
}

.tab-btn.active {
    background: linear-gradient(135deg, var(--primary), var(--primary-dark));
    color: #ffffff;
    box-shadow: 0 12px 24px rgba(79, 70, 229, 0.24);
}

.tabs-content {
    position: relative;
}

.tab-panel {
    display: none;
}

.tab-panel.active {
    display: block;
}

.panel-card {
    background: linear-gradient(180deg, #ffffff, #f8fafc);
    border: 1px solid #e2e8f0;
    border-radius: 24px;
    padding: 28px;
    min-height: 280px;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.7);
}

.panel-badge {
    display: inline-flex;
    align-items: center;
    padding: 8px 12px;
    border-radius: 999px;
    background: var(--soft);
    color: var(--primary);
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 0.03em;
    margin-bottom: 18px;
}

.panel-card h2 {
    margin: 0 0 14px;
    font-size: clamp(24px, 4vw, 36px);
    line-height: 1.15;
    font-weight: 800;
}

.panel-card p {
    margin: 0;
    color: var(--muted);
    font-size: 16px;
    line-height: 1.75;
    max-width: 680px;
}

.panel-card code {
    padding: 2px 8px;
    border-radius: 8px;
    background: #eef2ff;
    color: var(--primary-dark);
    font-size: 0.95em;
}

@media (max-width: 768px) {
    .tabs {
        padding: 16px;
        border-radius: 22px;
    }

    .tabs-nav {
        gap: 10px;
        border-radius: 18px;
    }

    .tab-btn {
        flex: 1 1 calc(50% - 10px);
        text-align: center;
        padding: 13px 16px;
    }

    .panel-card {
        padding: 22px;
        min-height: auto;
    }
}

@media (max-width: 480px) {
    body {
        padding: 20px 12px;
    }

    .tab-btn {
        flex: 1 1 100%;
    }

    .panel-card {
        border-radius: 18px;
        padding: 18px;
    }

    .tabs {
        border-radius: 18px;
    }
}