:root {
    --bg-main: #060d18;
    --bg-card: #0d1b2a;
    --bg-card-hover: #142840;
    --primary: #ff6b2c;
    --primary-hover: #e55a22;
    --accent: #ffd600;
    --success: #00d4aa;
    --text-main: #e0e8f0;
    --text-muted: #7a8fa6;
    --border: rgba(255, 255, 255, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.6;
    padding: 40px 20px;
}

.container {
    max-width: 900px;
    margin: 0 auto;
}

/* Header & Progress Bar */
.header {
    text-align: center;
    margin-bottom: 40px;
}

.header h1 {
    font-family: 'Outfit', sans-serif;
    font-size: 2.5rem;
    color: #fff;
    margin-bottom: 10px;
}

.highlight {
    color: var(--primary);
}

.header p {
    color: var(--text-muted);
    font-size: 1.1rem;
    margin-bottom: 30px;
}

.progress-wrapper {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 20px;
    margin-bottom: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

.progress-info {
    display: flex;
    justify-content: space-between;
    margin-bottom: 10px;
    font-weight: 600;
    font-size: 0.95rem;
}

.progress-bar {
    height: 12px;
    background: rgba(255,255,255,0.05);
    border-radius: 6px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    width: 0%;
    transition: width 0.4s ease;
}

/* Tabs */
.tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 25px;
    overflow-x: auto;
    padding-bottom: 5px;
}

.tab-btn {
    flex: 1;
    background: rgba(255,255,255,0.05);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 15px 20px;
    font-size: 1rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    white-space: nowrap;
}

.tab-btn:hover {
    background: rgba(255,255,255,0.1);
    color: #fff;
}

.tab-btn.active {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

/* Tab Content & Card */
.tab-content {
    display: none;
    animation: fadeIn 0.4s ease;
}

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

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 30px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.3);
}

.card h2 {
    font-family: 'Outfit', sans-serif;
    color: #fff;
    font-size: 1.8rem;
    margin-bottom: 10px;
}

.subtitle {
    color: var(--text-muted);
    margin-bottom: 30px;
    font-size: 1.05rem;
}

/* Checklist */
.checklist {
    list-style: none;
}

.checklist li {
    margin-bottom: 15px;
}

.check-item {
    display: flex;
    align-items: flex-start;
    padding: 20px;
    background: rgba(255,255,255,0.03);
    border: 1px solid rgba(255,255,255,0.05);
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s;
}

.check-item:hover {
    background: rgba(255,255,255,0.06);
    border-color: rgba(255,255,255,0.1);
}

.check-item input {
    position: absolute;
    opacity: 0;
    cursor: pointer;
    height: 0;
    width: 0;
}

.checkmark {
    min-width: 24px;
    height: 24px;
    background-color: transparent;
    border: 2px solid var(--text-muted);
    border-radius: 6px;
    margin-right: 15px;
    margin-top: 2px;
    position: relative;
    transition: all 0.2s;
}

.check-item:hover input ~ .checkmark {
    border-color: var(--primary);
}

.check-item input:checked ~ .checkmark {
    background-color: var(--success);
    border-color: var(--success);
}

.checkmark:after {
    content: "";
    position: absolute;
    display: none;
    left: 7px;
    top: 3px;
    width: 5px;
    height: 10px;
    border: solid white;
    border-width: 0 2px 2px 0;
    transform: rotate(45deg);
}

.check-item input:checked ~ .checkmark:after {
    display: block;
}

.item-content {
    flex: 1;
}

.item-content strong {
    display: block;
    color: #fff;
    font-size: 1.1rem;
    margin-bottom: 8px;
    transition: color 0.2s;
}

.item-content p {
    color: var(--text-muted);
    font-size: 0.95rem;
}

.check-item input:checked ~ .item-content strong {
    color: var(--success);
}

.check-item input:checked ~ .item-content p {
    opacity: 0.7;
}

.code-block {
    background: #000;
    padding: 15px;
    border-radius: 6px;
    margin-top: 15px;
    font-family: monospace;
    font-size: 0.85rem;
    color: #a8c7fa;
    overflow-x: auto;
    border: 1px solid #333;
}

@media (max-width: 768px) {
    .tabs {
        flex-direction: column;
    }
    .card {
        padding: 20px;
    }
}