/* === Reset & Base === */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #3776AB;
    --primary-dark: #2C5F85;
    --secondary: #FFD43B;
    --accent: #4B8BBE;
    --dark: #1a1a2e;
    --darker: #0f0f1a;
    --light: #f8f9fa;
    --gray: #6c757d;
    --success: #28a745;
    --gradient: linear-gradient(135deg, #3776AB 0%, #4B8BBE 50%, #FFD43B 100%);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    line-height: 1.6;
    color: #333;
    background: var(--light);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* === Hero === */
.hero {
    background: var(--dark);
    color: white;
    padding: 100px 20px 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    overflow: hidden;
    opacity: 0.3;
}

.python-logo {
    position: absolute;
    font-size: 200px;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(-50%, -50%) rotate(-5deg); }
    50% { transform: translate(-50%, -50%) rotate(5deg); }
}

.code-float {
    position: absolute;
    font-family: 'JetBrains Mono', monospace;
    font-size: 14px;
    color: var(--secondary);
    opacity: 0.7;
    animation: drift 20s linear infinite;
}

.code-1 { top: 20%; left: -200px; animation-delay: 0s; }
.code-2 { top: 40%; left: -300px; animation-delay: 5s; }
.code-3 { top: 60%; left: -250px; animation-delay: 10s; }
.code-4 { top: 80%; left: -350px; animation-delay: 15s; }

@keyframes drift {
    from { transform: translateX(0); }
    to { transform: translateX(calc(100vw + 400px)); }
}

.hero-badge {
    display: inline-block;
    background: var(--secondary);
    color: var(--dark);
    padding: 8px 20px;
    border-radius: 30px;
    font-weight: 600;
    font-size: 14px;
    margin-bottom: 30px;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

.hero h1 {
    font-size: clamp(2.5rem, 6vw, 4rem);
    font-weight: 800;
    margin-bottom: 20px;
    position: relative;
    z-index: 1;
}

.highlight {
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: #adb5bd;
    max-width: 600px;
    margin: 0 auto 40px;
    position: relative;
    z-index: 1;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 60px;
    margin-bottom: 40px;
    position: relative;
    z-index: 1;
}

.stat {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 3rem;
    font-weight: 800;
    color: var(--secondary);
}

.stat-label {
    font-size: 0.9rem;
    color: #adb5bd;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-primary {
    display: inline-block;
    background: var(--gradient);
    color: white;
    padding: 16px 40px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s;
    position: relative;
    z-index: 1;
    box-shadow: 0 4px 20px rgba(55, 118, 171, 0.4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 30px rgba(55, 118, 171, 0.5);
}

/* === Section Common === */
section {
    padding: 80px 20px;
}

h2 {
    text-align: center;
    font-size: 2.2rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--dark);
}

.section-subtitle {
    text-align: center;
    color: var(--gray);
    margin-bottom: 50px;
    font-size: 1.1rem;
}

/* === Why Python === */
.why-python {
    background: white;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.feature-card {
    background: var(--light);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.feature-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--dark);
}

.feature-card p {
    color: var(--gray);
    font-size: 0.95rem;
}

/* === Plan Section === */
.plan-section {
    background: var(--light);
}

.week-card {
    background: white;
    border-radius: 20px;
    padding: 30px;
    margin-bottom: 40px;
    box-shadow: 0 5px 30px rgba(0, 0, 0, 0.08);
}

.week-header {
    display: flex;
    align-items: center;
    gap: 20px;
    margin-bottom: 30px;
}

.week-badge {
    background: var(--gradient);
    color: white;
    padding: 8px 20px;
    border-radius: 25px;
    font-weight: 600;
    font-size: 0.9rem;
}

.week-header h3 {
    font-size: 1.5rem;
    color: var(--dark);
}

.days-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.day-card {
    background: var(--light);
    border-radius: 15px;
    padding: 25px;
    position: relative;
    border-left: 4px solid var(--primary);
    transition: all 0.3s;
    cursor: pointer;
}

.day-card:hover {
    transform: translateX(5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

.day-card.completed {
    background: #d4edda;
    border-left-color: var(--success);
}

.day-card.completed::after {
    content: '✓';
    position: absolute;
    top: 15px;
    right: 15px;
    background: var(--success);
    color: white;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

.day-card.featured {
    border-left-color: var(--secondary);
    background: linear-gradient(135deg, #fff9e6 0%, #fff 100%);
}

.day-number {
    display: inline-block;
    background: var(--primary);
    color: white;
    width: 35px;
    height: 35px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 0.9rem;
    margin-bottom: 15px;
}

.day-card.featured .day-number {
    background: var(--secondary);
    color: var(--dark);
}

.day-card h4 {
    font-size: 1.1rem;
    margin-bottom: 10px;
    color: var(--dark);
}

.day-card p {
    font-size: 0.9rem;
    color: var(--gray);
    margin-bottom: 15px;
}

.day-card code {
    background: rgba(55, 118, 171, 0.1);
    color: var(--primary);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
}

.day-time {
    font-size: 0.85rem;
    color: var(--accent);
    font-weight: 500;
}

/* === Tips === */
.tips-section {
    background: white;
}

.tips-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.tip-card {
    display: flex;
    gap: 20px;
    padding: 30px;
    background: var(--light);
    border-radius: 15px;
    transition: all 0.3s;
}

.tip-card:hover {
    background: var(--dark);
    color: white;
}

.tip-card:hover h4,
.tip-card:hover p {
    color: white;
}

.tip-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
}

.tip-card h4 {
    font-size: 1.1rem;
    margin-bottom: 10px;
    color: var(--dark);
}

.tip-card p {
    font-size: 0.95rem;
    color: var(--gray);
}

/* === Resources === */
.resources-section {
    background: var(--dark);
    color: white;
}

.resources-section h2 {
    color: white;
}

.resources-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 20px;
}

.resource-card {
    background: rgba(255, 255, 255, 0.1);
    padding: 30px 20px;
    border-radius: 15px;
    text-align: center;
    text-decoration: none;
    color: white;
    transition: all 0.3s;
    border: 2px solid transparent;
}

.resource-card:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: var(--secondary);
    transform: translateY(-5px);
}

.resource-icon {
    font-size: 2.5rem;
    margin-bottom: 15px;
}

.resource-card h4 {
    font-size: 1rem;
    margin-bottom: 5px;
}

.resource-card p {
    font-size: 0.85rem;
    color: #adb5bd;
}

/* === Progress === */
.progress-section {
    background: white;
}

.progress-bar-container {
    max-width: 600px;
    margin: 0 auto 40px;
    text-align: center;
}

.progress-bar {
    height: 30px;
    background: var(--light);
    border-radius: 15px;
    overflow: hidden;
    margin-bottom: 15px;
    box-shadow: inset 0 2px 5px rgba(0, 0, 0, 0.1);
}

.progress-fill {
    height: 100%;
    background: var(--gradient);
    border-radius: 15px;
    width: 0%;
    transition: width 0.5s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 0.9rem;
}

.progress-text {
    font-size: 1rem;
    color: var(--gray);
}

.days-checklist {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
    max-width: 800px;
    margin: 0 auto;
}

.day-check {
    width: 50px;
    height: 50px;
    border-radius: 10px;
    background: var(--light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    border: 2px solid transparent;
}

.day-check:hover {
    transform: scale(1.1);
    border-color: var(--primary);
}

.day-check.checked {
    background: var(--success);
    color: white;
}

/* === FAQ === */
.faq-section {
    background: var(--light);
}

.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: white;
    border-radius: 15px;
    margin-bottom: 15px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.faq-question {
    padding: 25px 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    font-weight: 600;
    font-size: 1.05rem;
    color: var(--dark);
    transition: background 0.3s;
}

.faq-question:hover {
    background: var(--light);
}

.faq-arrow {
    transition: transform 0.3s;
    color: var(--primary);
}

.faq-item.active .faq-arrow {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-item.active .faq-answer {
    max-height: 200px;
}

.faq-answer p {
    padding: 0 30px 25px;
    color: var(--gray);
    line-height: 1.7;
}

/* === Footer === */
.footer {
    background: var(--darker);
    color: white;
    padding: 40px 20px;
    text-align: center;
}

.footer-content p:first-child {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 10px;
}

.footer-sub {
    color: #6c757d;
    font-size: 0.9rem;
}

/* === Responsive === */
@media (max-width: 768px) {
    .hero {
        padding: 60px 20px;
    }

    .hero-stats {
        gap: 30px;
    }

    .stat-number {
        font-size: 2rem;
    }

    .week-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }

    .days-grid {
        grid-template-columns: 1fr;
    }

    .day-check {
        width: 40px;
        height: 40px;
        font-size: 0.85rem;
    }
}

/* === Animations === */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feature-card,
.day-card,
.tip-card,
.resource-card {
    animation: fadeInUp 0.6s ease forwards;
    opacity: 0;
}

.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }
.feature-card:nth-child(4) { animation-delay: 0.4s; }