:root {
    --primary-red: #c52222;
    /* Approximate from logo/active states */
    --primary-red-hover: #a11b1b;
    --primary-red-light: #fce8e8;
    /* Light red for icon backgrounds */

    --bg-color: #f4f6fa;
    /* Light grayish blue background */
    --surface-color: #ffffff;
    /* White cards */

    --text-primary: #111827;
    /* Dark navy/black for headings */
    --text-secondary: #64748b;
    /* Slate gray for secondary text */
    --text-tertiary: #94a3b8;
    /* Lighter gray for subtle text */

    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-pill: 9999px;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.025);

    --font-family: 'Inter', sans-serif;

    --transition-fast: 0.2s ease;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
    /* Accounts for sticky header */
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.5;
    overflow-x: hidden;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

/* Utilities */
.text-highlight {
    color: var(--primary-red);
}

.justify-center {
    justify-content: center !important;
}

/* --- Header / Navbar --- */
.navbar {
    background-color: var(--surface-color);
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-sm);
    padding: 16px 0;
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    font-size: 24px;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.logo-black {
    color: #111827;
}

.logo-red {
    color: var(--primary-red);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.nav-links a:not(.btn) {
    font-weight: 500;
    color: var(--text-secondary);
    transition: color var(--transition-fast);
}

.nav-links a:not(.btn):hover {
    color: var(--text-primary);
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    border-radius: var(--radius-pill);
    font-weight: 600;
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-primary {
    background-color: var(--primary-red);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-red-hover);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(197, 34, 34, 0.3);
}

.btn-sm {
    padding: 10px 20px;
    font-size: 14px;
}

/* --- Hero Section --- */
.hero {
    display: flex;
    align-items: center;
    justify-content: space-between;
    min-height: calc(100vh - 72px);
    padding: 60px 0;
    gap: 60px;
}

.hero-content {
    flex: 1;
    max-width: 600px;
}

.hero-title {
    font-size: 56px;
    margin-bottom: 24px;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 40px;
    font-weight: 400;
}

/* Store Buttons */
.store-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 48px;
    flex-wrap: wrap;
}

.store-btn {
    display: flex;
    align-items: center;
    gap: 12px;
    background-color: #111827;
    color: white;
    padding: 12px 24px;
    border-radius: 12px;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.store-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

.whatsapp-btn {
    background-color: #25D366;
    color: white;
}

.whatsapp-btn:hover {
    background-color: #1ebd5b;
    box-shadow: 0 8px 16px rgba(37, 211, 102, 0.3);
}

.store-btn i {
    font-size: 28px;
}

.store-text {
    display: flex;
    flex-direction: column;
}

.store-text span {
    font-size: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.store-text strong {
    font-size: 16px;
    font-weight: 600;
}

.stats {
    display: flex;
    gap: 48px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 32px;
    font-weight: 800;
    color: var(--text-primary);
}

.stat-label {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 500;
}

/* --- Phone Mockup --- */
.hero-image-wrapper {
    flex: 1;
    display: flex;
    justify-content: center;
    position: relative;
}

.phone-mockup {
    width: 320px;
    height: 650px;
    background-color: #1e293b;
    border-radius: 40px;
    padding: 12px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    position: relative;
}



.phone-screen {
    width: 100%;
    height: 100%;
    background-color: var(--bg-color);
    border-radius: 32px;
    overflow: hidden;
    position: relative;
    display: flex;
    flex-direction: column;
}

/* App Header inside mockup */
.app-header {
    background: var(--surface-color);
    padding: 40px 20px 16px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.app-header .logo {
    font-size: 18px;
}

.app-header-icons {
    display: flex;
    align-items: center;
    gap: 16px;
    color: var(--text-secondary);
}

.app-header-icons .avatar {
    width: 28px;
    height: 28px;
    background-color: #1e293b;
    border-radius: 50%;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
}

.app-section-title {
    padding: 24px 20px 12px;
    font-size: 12px;
    font-weight: 700;
    color: var(--text-secondary);
    letter-spacing: 1px;
}

/* App Cards inside mockup */
.app-card {
    background: var(--surface-color);
    margin: 8px 20px;
    padding: 16px;
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    gap: 16px;
    box-shadow: var(--shadow-sm);
}

.card-icon {
    width: 40px;
    height: 40px;
    background-color: var(--primary-red-light);
    color: var(--primary-red);
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.card-content h4 {
    font-size: 15px;
    margin-bottom: 2px;
}

.card-content p {
    font-size: 12px;
    color: var(--text-secondary);
}

.app-card .chevron {
    margin-left: auto;
    color: var(--text-tertiary);
    font-size: 12px;
}

/* Semester Progress Card */
.semester-card {
    background: var(--surface-color);
    margin: 16px 20px;
    padding: 20px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
    position: relative;
    overflow: hidden;
}

.sem-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 4px;
}

.sem-icon {
    width: 32px;
    height: 32px;
    background-color: #f5ebe6;
    /* specific color from screenshot */
    color: #8c6a5d;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.sem-header h4 {
    font-size: 16px;
}

.sem-sub {
    font-size: 13px;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.progress-chart {
    height: 60px;
    position: relative;
    margin-bottom: 8px;
}

.wave {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 30px;
    background-color: #8c6a5d;
    border-top-left-radius: 8px;
    border-top-right-radius: 8px;
}

.progress-badge {
    position: absolute;
    right: 0;
    top: 0;
    background-color: #f5ebe6;
    color: #8c6a5d;
    padding: 4px 12px;
    border-radius: var(--radius-pill);
    font-size: 12px;
    font-weight: 700;
}

.sem-footer {
    display: flex;
    justify-content: space-between;
    font-size: 11px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.almost-there {
    text-align: center;
    font-size: 13px;
    font-weight: 600;
    color: #5c6c80;
}

/* Bottom Nav inside mockup */
.bottom-nav {
    position: absolute;
    bottom: 0;
    width: 100%;
    background: var(--surface-color);
    display: flex;
    justify-content: space-between;
    padding: 16px 24px 24px;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.05);
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    color: var(--text-tertiary);
    font-size: 10px;
    font-weight: 600;
}

.nav-item i {
    font-size: 18px;
    margin-bottom: 2px;
}

.nav-item.active {
    color: var(--primary-red);
}


/* --- Features Section --- */
.features-section {
    padding: 80px 0;
    background-color: var(--surface-color);
}

.section-title {
    font-size: 40px;
    text-align: center;
    margin-bottom: 80px;
    letter-spacing: -0.5px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
}

.feature-block {
    background-color: var(--bg-color);
    padding: 28px 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

.feature-block:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.feature-icon-wrapper {
    width: 64px;
    height: 64px;
    background-color: var(--primary-red-light);
    color: var(--primary-red);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin: 0 auto 24px;
}

.feature-block h3 {
    font-size: 20px;
    margin-bottom: 12px;
}

.feature-block p {
    color: var(--text-secondary);
    font-size: 15px;
}

/* --- FAQ Section --- */
.faq-accordion {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.faq-item {
    background-color: var(--surface-color);
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
    overflow: hidden;
    transition: box-shadow var(--transition-fast);
}

.faq-item:hover {
    box-shadow: var(--shadow-md);
}

.faq-question {
    width: 100%;
    text-align: left;
    padding: 24px;
    background: none;
    border: none;
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-family: var(--font-family);
}

.faq-question i {
    color: var(--primary-red);
    transition: transform 0.3s ease;
}

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

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

.faq-answer p {
    padding: 0 24px 24px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* --- CTA Section --- */
.cta-section {
    padding: 60px 0;
    background-color: var(--bg-color);
    color: var(--text-primary);
    text-align: center;
}

.cta-container h2 {
    color: var(--text-primary);
    font-size: 36px;
    margin-bottom: 16px;
}

.cta-container p {
    font-size: 18px;
    color: var(--text-secondary);
    margin-bottom: 32px;
}

.cta-section .store-buttons {
    margin-bottom: 0;
}

.cta-section .store-btn {
    background-color: #111827;
    color: white;
}

.cta-section .store-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(0, 0, 0, 0.2);
}

/* --- Footer --- */
.footer {
    background-color: var(--surface-color);
    color: var(--text-secondary);
    padding: 40px 0 24px;
    border-top: 1px solid #e2e8f0;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 48px;
    margin-bottom: 32px;
}

.footer-logo p {
    margin-top: 16px;
    font-size: 14px;
}

.footer-links {
    display: flex;
    gap: 60px;
}

.link-column {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.link-column h4 {
    color: var(--text-primary);
    font-size: 16px;
    margin-bottom: 8px;
}

.link-column a {
    font-size: 14px;
    transition: color var(--transition-fast);
}

.link-column a:hover {
    color: var(--primary-red);
}

.footer-bottom {
    text-align: center;
    font-size: 14px;
    padding-top: 24px;
    border-top: 1px solid #e2e8f0;
}

/* --- Responsive --- */
@media (max-width: 900px) {
    .hero {
        flex-direction: column;
        text-align: center;
        padding-top: 40px;
        gap: 40px;
    }

    .hero-content {
        display: flex;
        flex-direction: column;
        align-items: center;
    }

    .hero-title {
        font-size: 44px;
    }

    .store-buttons {
        justify-content: center;
    }

    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .footer-logo .logo {
        justify-content: center;
    }

    .footer-links {
        flex-direction: column;
        gap: 32px;
    }
}

@media (max-width: 600px) {
    .hero-title {
        font-size: 36px;
    }

    .nav-links a:not(.btn) {
        display: none;
    }

    .hero-image-wrapper {
        transform: scale(0.85);
        transform-origin: top center;
    }

    .stats {
        flex-direction: column;
        gap: 24px;
    }

    .section-title {
        font-size: 32px;
    }

    .cta-container h2 {
        font-size: 28px;
    }
}

/* --- Modal --- */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.4);
    z-index: 1000;
    display: flex;
    align-items: flex-end;
    /* Bottom sheet style */
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--transition-fast);
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background-color: var(--surface-color);
    width: 100%;
    max-width: 600px;
    max-height: 90vh;
    border-top-left-radius: 32px;
    border-top-right-radius: 32px;
    padding: 16px 24px 32px;
    transform: translateY(100%);
    transition: transform 0.3s cubic-bezier(0.2, 0.8, 0.2, 1);
    display: flex;
    flex-direction: column;
}

.modal-overlay.active .modal-content {
    transform: translateY(0);
}

@media (min-width: 600px) {
    .modal-overlay {
        align-items: center;
    }

    .modal-content {
        border-radius: 32px;
        transform: scale(0.95);
    }

    .modal-overlay.active .modal-content {
        transform: scale(1);
    }
}

.modal-drag-handle {
    width: 40px;
    height: 4px;
    background-color: #e2e8f0;
    border-radius: 2px;
    margin: 0 auto 16px;
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 24px;
}

.modal-title-wrapper {
    display: flex;
    align-items: center;
    gap: 12px;
}

.modal-icon {
    width: 40px;
    height: 40px;
    background-color: var(--primary-red);
    color: white;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 18px;
}

.modal-header h3 {
    font-size: 20px;
}

.modal-close {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: none;
    background-color: #f1f5f9;
    color: #475569;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    font-size: 16px;
    transition: background-color var(--transition-fast);
}

.modal-close:hover {
    background-color: #e2e8f0;
}

.modal-body {
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding-right: 8px;
    -ms-overflow-style: none;
    /* IE and Edge */
    scrollbar-width: none;
    /* Firefox */
}

.modal-body::-webkit-scrollbar {
    display: none;
    /* Chrome, Safari, Opera */
}

.modal-card {
    display: flex;
    gap: 16px;
    padding: 16px;
    background-color: #f8fafc;
    border-radius: 16px;
    align-items: flex-start;
}

.modal-card.highlight {
    background-color: var(--primary-red-light);
}

.modal-card.highlight h4 {
    color: var(--primary-red);
}

.modal-card-icon {
    width: 36px;
    height: 36px;
    background-color: white;
    color: #64748b;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    box-shadow: var(--shadow-sm);
}

.modal-card.highlight .modal-card-icon {
    color: var(--primary-red);
}

.modal-card-text h4 {
    font-size: 15px;
    margin-bottom: 4px;
}

.modal-card-text p {
    font-size: 13px;
    color: var(--text-secondary);
}

/* --- Responsive Design / Mobile Optimization --- */
@media (max-width: 900px) {
    .hero {
        flex-direction: column;
        text-align: center;
        gap: 40px;
        padding: 40px 0;
    }

    .hero-title {
        font-size: 44px;
    }

    .hero-content {
        margin: 0 auto;
        display: flex;
        flex-direction: column;
        align-items: center;
    }
}

@media (max-width: 600px) {
    .container {
        padding: 0 16px;
    }

    .nav-content {
        flex-direction: row;
        justify-content: space-between;
    }

    .nav-links {
        width: auto;
        gap: 10px;
    }

    .nav-links a:not(.btn) {
        display: none;
    }

    .hero-title {
        font-size: 36px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .store-buttons {
        flex-direction: column;
        width: 100%;
    }

    .store-btn {
        width: 100%;
        justify-content: center;
    }

    .multi-phones {
        gap: 8px;
    }

    .multi-phones img {
        width: 130px !important;
        height: 280px !important;
        border-radius: 12px !important;
    }

    .features-section {
        padding: 40px 0;
    }

    .section-title {
        font-size: 32px;
        margin-bottom: 40px;
    }

    .showcase-grid {
        gap: 16px;
    }

    .phone-mockup {
        width: 240px;
        height: 480px;
    }

    .cta-section {
        padding: 40px 0;
    }

    .footer-content {
        flex-direction: column;
        text-align: center;
        gap: 32px;
    }

    .footer-logo .logo {
        justify-content: center;
    }

    .footer-links {
        width: 100%;
        justify-content: center;
        flex-wrap: wrap;
        gap: 32px;
    }
}

/* Nav Logo */
.nav-logo-img {
    height: 32px;
    width: auto;
    border-radius: 8px;
    margin-right: 8px;
}

/* Screenshots Section */
.screenshots-section {
    padding: 80px 20px;
    background-color: var(--surface-color);
    border-radius: 32px;
    margin: 40px auto;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
}

.screenshots-grid {
    display: flex;
    overflow-x: auto;
    gap: 24px;
    padding: 20px 0;
    margin-top: 40px;
    scroll-snap-type: x mandatory;
    /* Hide scrollbar for cleaner look */
    -ms-overflow-style: none;  
    scrollbar-width: none;  
}

.screenshots-grid::-webkit-scrollbar {
    display: none;
}

.screenshot-img {
    height: 500px;
    width: auto;
    border-radius: 24px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1), 0 8px 10px -6px rgba(0, 0, 0, 0.1);
    scroll-snap-align: center;
    border: 4px solid #f1f5f9;
}

@media (max-width: 768px) {
    .screenshot-img {
        height: 400px;
    }
}