:root {
    --primary: #4361ee;
    --primary-light: #4895ef;
    --primary-dark: #3a56d5;
    --secondary: #f72585;
    --dark: #2b2d42;
    --dark-light: #4a4e69;
    --light: #f8f9fa;
    --lighter: #fefefe;
    --gray: #6c757d;
    --gray-light: #e9ecef;
    --success: #4cc9f0;
    --border-radius: 14px;
    --box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.7;
    margin: 0;
    padding: 0;
    background-color: #f6f7fb;
    color: var(--dark);
    -webkit-font-smoothing: antialiased;
}

.container {
    max-width: 920px;
    margin: 0 auto;
    padding: 2.5rem 1.75rem;
}

.header {
    text-align: center;
    margin-bottom: 3.5rem;
}

.header h1 {
    color: var(--dark);
    font-size: 2.75rem;
    font-weight: 800;
    margin-bottom: 0.75rem;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.5px;
}

.header p {
    color: var(--dark-light);
    font-size: 1.15rem;
    max-width: 680px;
    margin: 0 auto;
    font-weight: 400;
    line-height: 1.6;
}

.guide-container {
    display: grid;
    gap: 2rem;
}

.step-card {
    background: var(--lighter);
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    padding: 2.25rem;
    transition: var(--transition);
    border: 1px solid rgba(0, 0, 0, 0.03);
    position: relative;
    overflow: hidden;
}

.step-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.12);
}

.step-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 4px;
    height: 100%;
    background: linear-gradient(to bottom, var(--primary), var(--primary-light));
}

.step-header {
    display: flex;
    align-items: center;
    margin-bottom: 1.75rem;
}

.step-number {
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    width: 42px;
    height: 42px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    margin-right: 1.25rem;
    flex-shrink: 0;
    font-size: 1.1rem;
    box-shadow: 0 4px 12px rgba(67, 97, 238, 0.3);
}

.step-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark);
    margin: 0;
    letter-spacing: -0.25px;
}

.step-content {
    color: var(--dark-light);
    line-height: 1.8;
    padding-left: calc(42px + 1.25rem);
    font-size: 1.05rem;
}

.step-content ol {
    padding-left: 1.75rem;
}

.step-content li {
    margin-bottom: 1rem;
    position: relative;
    padding-left: 0.5rem;
}

.step-content li::marker {
    color: var(--primary);
    font-weight: 600;
}

.step-content strong {
    color: var(--dark);
    font-weight: 600;
    background-color: rgba(67, 97, 238, 0.08);
    padding: 0.15rem 0.35rem;
    border-radius: 4px;
}

.step-content a {
    color: var(--primary);
    font-weight: 500;
    text-decoration: none;
    border-bottom: 1px dashed var(--primary);
    transition: var(--transition);
}

.step-content a:hover {
    color: var(--primary-dark);
    border-bottom: 1px solid var(--primary-dark);
}

.video-wrapper {
    margin: 2rem 0;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    position: relative;
}

.video-wrapper::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(45deg, var(--primary), var(--secondary));
    opacity: 0.15;
    z-index: 1;
    pointer-events: none;
}

.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    height: 0;
    overflow: hidden;
    border-radius: 12px;
    background: #000;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.action-buttons {
    display: flex;
    justify-content: center;
    gap: 1.25rem;
    margin: 4rem 0;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 1rem 2.25rem;
    background: linear-gradient(135deg, var(--primary), var(--primary-light));
    color: white;
    border-radius: var(--border-radius);
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    border: none;
    cursor: pointer;
    box-shadow: 0 6px 15px rgba(67, 97, 238, 0.25);
    font-size: 1.05rem;
    gap: 0.5rem;
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 25px rgba(67, 97, 238, 0.3);
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
}

.btn-outline {
    background: white;
    color: var(--primary);
    border: 1px solid var(--primary);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
}

.btn-outline:hover {
    background: rgba(67, 97, 238, 0.05);
    border-color: var(--primary-dark);
    color: var(--primary-dark);
}

.btn svg {
    width: 18px;
    height: 18px;
}

.footer {
    text-align: center;
    margin-top: 5rem;
    padding-top: 2.5rem;
    border-top: 1px solid rgba(0, 0, 0, 0.06);
    color: var(--gray);
}

.footer a {
    color: var(--primary);
    font-weight: 500;
    text-decoration: none;
    transition: var(--transition);
}

.footer a:hover {
    color: var(--primary-dark);
    text-decoration: underline;
}

.note-box {
    background: rgba(67, 97, 238, 0.06);
    border-left: 4px solid var(--primary);
    padding: 1.25rem;
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
    margin: 1.5rem 0;
}

.note-box strong {
    color: var(--primary);
    font-weight: 600;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 1.75rem 1.25rem;
    }
    
    .header h1 {
        font-size: 2.25rem;
    }
    
    .header p {
        font-size: 1.05rem;
    }
    
    .step-card {
        padding: 1.75rem;
    }
    
    .step-content {
        padding-left: 0;
        font-size: 1rem;
    }
    
    .action-buttons {
        flex-direction: column;
        gap: 1rem;
        margin: 3rem 0;
    }
    
    .btn {
        width: 100%;
        padding: 1rem;
    }
}

/* Animation */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(15px); }
    to { opacity: 1; transform: translateY(0); }
}

.step-card {
    animation: fadeIn 0.7s ease-out forwards;
    opacity: 0;
}

.step-card:nth-child(1) { animation-delay: 0.1s; }
.step-card:nth-child(2) { animation-delay: 0.2s; }
.step-card:nth-child(3) { animation-delay: 0.3s; }

/* Tooltip */
.tooltip {
    position: relative;
    display: inline-block;
    cursor: pointer;
}

.tooltip .tooltip-text {
    visibility: hidden;
    width: 220px;
    background-color: var(--dark);
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 0.75rem;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    transform: translateX(-50%);
    opacity: 0;
    transition: opacity 0.3s;
    font-size: 0.9rem;
    font-weight: normal;
}

.tooltip:hover .tooltip-text {
    visibility: visible;
    opacity: 1;
}