/* ========================================
   RESET
======================================== */

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


html {
    scroll-behavior: smooth;
}


/* Prevent sections from hiding behind navbar */

#home,
#concepts,
#working,
#comparison {
    scroll-margin-top: 90px;
}


/* ========================================
   BODY
======================================== */

body {
    font-family:
        Arial,
        Helvetica,
        sans-serif;

    background: #f4f7fb;

    color: #172033;

    line-height: 1.6;
}


/* ========================================
   GLOBAL CONTAINER
======================================== */

.container {
    width: min(1200px, 94%);
    margin: 0 auto;
}


/* ========================================
   NAVIGATION
======================================== */

.navbar {
    position: sticky;

    top: 0;

    z-index: 1000;

    background: #0f3d6e;

    color: white;

    box-shadow:
        0 4px 15px rgba(
            0,
            0,
            0,
            0.15
        );
}


.nav-container {
    width: min(1120px, 92%);

    min-height: 72px;

    margin: auto;

    display: flex;

    align-items: center;

    justify-content: space-between;

    gap: 25px;
}


.brand {
    display: flex;

    align-items: center;

    gap: 10px;

    color: white;

    text-decoration: none;
}


.brand-icon {
    width: 42px;

    height: 42px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: rgba(
        255,
        255,
        255,
        0.12
    );

    border-radius: 10px;

    font-size: 22px;
}


.brand strong {
    display: block;

    font-size: 16px;
}


.brand small {
    display: block;

    font-size: 11px;

    color: #bfdbfe;

    margin-top: 2px;
}


.nav-links {
    display: flex;

    align-items: center;

    gap: 25px;
}


.nav-links a {
    color: white;

    text-decoration: none;

    font-size: 14px;

    font-weight: 600;

    transition: 0.3s;
}


.nav-links a:hover {
    color: #93c5fd;
}


/* ========================================
   HERO
======================================== */

.hero {
    background:
        linear-gradient(
            135deg,
            #eaf3ff 0%,
            #ffffff 55%,
            #eef6ff 100%
        );

    padding: 75px 0;

    border-bottom: 1px solid #e1eaf5;
}


.hero-container {
    display: grid;

    grid-template-columns:
        1.05fr
        0.95fr;

    align-items: center;

    gap: 55px;
}


.hero-content {
    max-width: 650px;
}


.hero-badge {
    display: inline-block;

    background: #dbeafe;

    color: #1d4ed8;

    padding: 8px 15px;

    border-radius: 30px;

    font-size: 12px;

    font-weight: bold;

    letter-spacing: 1px;

    margin-bottom: 18px;
}


.hero h1 {
    color: #123b63;

    font-size:
        clamp(
            2.7rem,
            6vw,
            4.5rem
        );

    line-height: 1.05;

    margin-bottom: 22px;
}


.hero h1 span {
    color: #2563eb;
}


.hero-content > p {
    color: #4b5563;

    font-size: 18px;

    max-width: 600px;

    margin-bottom: 28px;
}


.hero-buttons {
    display: flex;

    gap: 13px;

    flex-wrap: wrap;
}


.primary-button,
.secondary-button {
    display: inline-block;

    padding: 13px 23px;

    border-radius: 8px;

    text-decoration: none;

    font-weight: bold;

    font-size: 14px;

    transition: 0.3s;
}


.primary-button {
    background: #2563eb;

    color: white;
}


.primary-button:hover {
    background: #1d4ed8;

    transform: translateY(-2px);
}


.secondary-button {
    background: white;

    color: #1d4ed8;

    border: 1px solid #bfdbfe;
}


.secondary-button:hover {
    background: #eff6ff;

    transform: translateY(-2px);
}


/* ========================================
   HERO NETWORK VISUAL
======================================== */

.hero-visual {
    display: flex;

    justify-content: center;
}


.network-card {
    width: 100%;

    max-width: 500px;

    background: white;

    padding: 35px 25px;

    border-radius: 22px;

    text-align: center;

    box-shadow:
        0 20px 50px rgba(
            30,
            64,
            175,
            0.15
        );

    border: 1px solid #dbeafe;
}


.network-icon {
    width: 70px;

    height: 70px;

    margin: 0 auto 15px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: #eff6ff;

    border-radius: 50%;

    font-size: 34px;
}


.network-card h3 {
    color: #123b63;

    font-size: 22px;

    margin-bottom: 8px;
}


.network-card > p {
    color: #6b7280;

    margin-bottom: 28px;
}


.network-card > p span {
    color: #2563eb;

    font-weight: bold;

    margin: 0 7px;
}


.network-flow {
    display: flex;

    align-items: center;

    justify-content: center;

    gap: 10px;
}


.network-node {
    width: 85px;

    padding: 12px 5px;

    background: #f8fbff;

    border: 1px solid #dbeafe;

    border-radius: 12px;
}


.network-node span {
    display: block;

    font-size: 25px;

    margin-bottom: 4px;
}


.network-node small {
    color: #526274;

    font-size: 12px;
}


.connection {
    color: #2563eb;

    font-size: 22px;

    font-weight: bold;
}


/* ========================================
   MAIN
======================================== */

main {
    padding: 70px 0;
}


/* ========================================
   SECTION HEADINGS
======================================== */

.section-heading {
    text-align: center;

    max-width: 750px;

    margin:
        0 auto
        35px;
}


.section-heading > span {
    color: #2563eb;

    font-size: 12px;

    font-weight: bold;

    letter-spacing: 2px;
}


.section-heading h2 {
    color: #123b63;

    font-size: 32px;

    margin:
        7px
        0
        10px;
}


.section-heading p {
    color: #6b7280;

    font-size: 15px;
}


/* ========================================
   INTERNET OVERVIEW
======================================== */

.overview-section {
    margin-bottom: 70px;
}


.overview-card {
    background: white;

    padding: 32px;

    border-radius: 18px;

    box-shadow:
        0 8px 25px rgba(
            0,
            0,
            0,
            0.07
        );

    border: 1px solid #e5e7eb;
}


.overview-text {
    max-width: 800px;

    margin: auto;

    text-align: center;
}


.section-number {
    display: inline-flex;

    align-items: center;

    justify-content: center;

    width: 38px;

    height: 38px;

    background: #dbeafe;

    color: #2563eb;

    border-radius: 50%;

    font-size: 12px;

    font-weight: bold;

    margin-bottom: 10px;
}


.overview-text h3 {
    color: #123b63;

    font-size: 24px;

    margin-bottom: 10px;
}


.overview-text p {
    color: #6b7280;
}


/* ========================================
   FLOW
======================================== */

.flow {
    display: flex;

    align-items: center;

    justify-content: center;

    gap: 14px;

    margin-top: 30px;

    flex-wrap: wrap;
}


.flow-box {
    min-width: 150px;

    background: #f5f9ff;

    border: 1px solid #bfdbfe;

    border-radius: 13px;

    padding: 18px;

    text-align: center;

    transition: 0.3s;
}


.flow-box:hover {
    transform: translateY(-4px);

    box-shadow:
        0 8px 20px rgba(
            37,
            99,
            235,
            0.12
        );
}


.flow-icon {
    display: block;

    font-size: 27px;

    margin-bottom: 6px;
}


.flow-box strong {
    display: block;

    color: #123b63;

    font-size: 15px;
}


.flow-box small {
    display: block;

    color: #6b7280;

    margin-top: 3px;

    font-size: 12px;
}


.flow-arrow {
    color: #2563eb;

    font-size: 25px;

    font-weight: bold;
}


/* ========================================
   NETWORK CONCEPT CARDS
======================================== */

.concept-section {
    margin-bottom: 70px;
}


.concept-grid {
    display: grid;

    grid-template-columns:
        repeat(4, 1fr);

    gap: 18px;
}


.concept-card {
    background: white;

    border: 1px solid #e5e7eb;

    border-radius: 16px;

    padding: 25px;

    box-shadow:
        0 6px 20px rgba(
            0,
            0,
            0,
            0.05
        );

    transition: 0.3s;
}


.concept-card:hover {
    transform: translateY(-6px);

    border-color: #bfdbfe;

    box-shadow:
        0 12px 28px rgba(
            37,
            99,
            235,
            0.12
        );
}


.concept-icon {
    width: 48px;

    height: 48px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: #eff6ff;

    border-radius: 12px;

    font-size: 23px;

    margin-bottom: 17px;
}


.concept-card h3 {
    color: #123b63;

    font-size: 18px;

    margin-bottom: 8px;
}


.concept-card p {
    color: #6b7280;

    font-size: 14px;
}


/* ========================================
   INFORMATION GRID
======================================== */

.information-grid {
    display: grid;

    grid-template-columns:
        repeat(2, 1fr);

    gap: 22px;

    margin-bottom: 70px;
}


.info-card {
    background: white;

    padding: 28px;

    border-radius: 17px;

    border: 1px solid #e5e7eb;

    box-shadow:
        0 7px 23px rgba(
            0,
            0,
            0,
            0.06
        );
}


.card-heading {
    display: flex;

    align-items: center;

    gap: 13px;

    margin-bottom: 22px;
}


.card-icon {
    width: 48px;

    height: 48px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: #eff6ff;

    border-radius: 12px;

    font-size: 22px;
}


.card-label {
    display: block;

    color: #2563eb;

    font-size: 10px;

    font-weight: bold;

    letter-spacing: 1.5px;

    margin-bottom: 2px;
}


.info-card h2 {
    color: #123b63;

    font-size: 21px;
}


.info-card > p {
    color: #5f6b7a;

    margin-bottom: 18px;
}


/* ========================================
   URL
======================================== */

.url-box {
    background: #101827;

    color: #8fe7ff;

    padding: 16px;

    border-radius: 10px;

    overflow-x: auto;

    white-space: nowrap;

    margin-bottom: 18px;

    font-family:
        Consolas,
        monospace;

    font-size: 14px;
}


.url-parts {
    display: grid;

    gap: 10px;
}


.url-parts div {
    display: flex;

    align-items: center;

    justify-content: space-between;

    gap: 15px;

    padding: 10px 12px;

    background: #f7faff;

    border-radius: 8px;
}


.url-parts strong {
    color: #1769aa;

    font-size: 13px;

    overflow-wrap: anywhere;
}


.url-parts span {
    color: #6b7280;

    font-size: 12px;

    white-space: nowrap;
}


/* ========================================
   DOMAIN HIGHLIGHT
======================================== */

.highlight-box {
    display: flex;

    align-items: flex-start;

    gap: 12px;

    background: #eff6ff;

    border-left: 4px solid #2563eb;

    padding: 15px;

    border-radius: 8px;
}


.highlight-box > span {
    font-size: 20px;
}


.highlight-box p {
    color: #475569;

    font-size: 14px;
}


/* ========================================
   BROWSER & SERVER
======================================== */

.browser-section {
    margin-bottom: 70px;
}


.browser-grid {
    display: grid;

    grid-template-columns:
        repeat(2, 1fr);

    gap: 22px;
}


.browser-card {
    display: flex;

    align-items: flex-start;

    gap: 20px;

    padding: 28px;

    background: white;

    border-radius: 17px;

    border: 1px solid #e5e7eb;

    box-shadow:
        0 7px 23px rgba(
            0,
            0,
            0,
            0.06
        );

    transition: 0.3s;
}


.browser-card:hover {
    transform: translateY(-4px);
}


.browser-icon {
    min-width: 60px;

    height: 60px;

    display: flex;

    align-items: center;

    justify-content: center;

    border-radius: 14px;

    background: #eff6ff;

    font-size: 28px;
}


.browser-card h3 {
    color: #123b63;

    font-size: 21px;

    margin-bottom: 7px;
}


.browser-card p {
    color: #667085;

    font-size: 14px;
}


/* ========================================
   WORKING PRINCIPLE
======================================== */

.working-section {
    margin-bottom: 70px;
}


.steps-container {
    display: grid;

    grid-template-columns:
        repeat(5, 1fr);

    gap: 14px;
}


.step-card {
    position: relative;

    background: white;

    padding: 25px 18px;

    border-radius: 15px;

    border: 1px solid #e5e7eb;

    box-shadow:
        0 6px 20px rgba(
            0,
            0,
            0,
            0.05
        );

    text-align: center;

    transition: 0.3s;
}


.step-card:hover {
    transform: translateY(-5px);

    border-color: #bfdbfe;

    box-shadow:
        0 10px 25px rgba(
            37,
            99,
            235,
            0.12
        );
}


.step-number {
    position: absolute;

    top: 12px;

    right: 12px;

    color: #2563eb;

    font-size: 10px;

    font-weight: bold;
}


.step-icon {
    width: 55px;

    height: 55px;

    margin: 8px auto 15px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: #eff6ff;

    border-radius: 50%;

    font-size: 24px;
}


.step-card h3 {
    color: #123b63;

    font-size: 16px;

    margin-bottom: 7px;
}


.step-card p {
    color: #6b7280;

    font-size: 13px;
}


/* ========================================
   CLIENT VS SERVER
======================================== */

.comparison-section {
    margin-bottom: 70px;
}


.comparison-card {
    display: grid;

    grid-template-columns:
        1fr
        auto
        1fr;

    align-items: stretch;

    background: white;

    border: 1px solid #e5e7eb;

    border-radius: 18px;

    overflow: hidden;

    box-shadow:
        0 8px 25px rgba(
            0,
            0,
            0,
            0.07
        );
}


.comparison-column {
    padding: 30px;
}


.comparison-header {
    display: flex;

    align-items: center;

    gap: 14px;

    margin-bottom: 24px;
}


.comparison-header > span {
    width: 50px;

    height: 50px;

    display: flex;

    align-items: center;

    justify-content: center;

    border-radius: 12px;

    background: #eff6ff;

    font-size: 23px;
}


.comparison-header h3 {
    color: #123b63;

    font-size: 21px;
}


.comparison-header small {
    color: #6b7280;

    font-size: 12px;
}


.comparison-item {
    display: flex;

    align-items: flex-start;

    gap: 10px;

    margin-bottom: 15px;
}


.comparison-item > span {
    width: 21px;

    height: 21px;

    flex-shrink: 0;

    display: flex;

    align-items: center;

    justify-content: center;

    background: #dbeafe;

    color: #2563eb;

    border-radius: 50%;

    font-size: 12px;

    font-weight: bold;
}


.comparison-item p {
    color: #5f6b7a;

    font-size: 14px;
}


.comparison-divider {
    display: flex;

    align-items: center;

    justify-content: center;

    padding: 0 15px;

    color: white;

    font-size: 13px;

    font-weight: bold;

    background: #1769aa;
}


/* ========================================
   SUMMARY
======================================== */

.summary-section {
    margin-bottom: 20px;
}


.summary-card {
    display: flex;

    align-items: center;

    gap: 22px;

    background:
        linear-gradient(
            135deg,
            #123c69,
            #1769aa
        );

    color: white;

    padding: 32px;

    border-radius: 18px;

    box-shadow:
        0 12px 30px rgba(
            23,
            105,
            170,
            0.2
        );
}


.summary-icon {
    min-width: 65px;

    height: 65px;

    display: flex;

    align-items: center;

    justify-content: center;

    background: rgba(
        255,
        255,
        255,
        0.12
    );

    border-radius: 15px;

    font-size: 30px;
}


.summary-card > div:last-child > span {
    font-size: 11px;

    letter-spacing: 1.5px;

    color: #bfdbfe;

    font-weight: bold;
}


.summary-card h2 {
    font-size: 24px;

    margin:
        5px
        0
        7px;
}


.summary-card p {
    color: #dbeafe;

    font-size: 14px;

    max-width: 750px;
}


/* ========================================
   FOOTER
======================================== */

footer {
    background: #101827;

    color: white;

    margin-top: 30px;
}


.footer-content {
    width: min(1120px, 92%);

    margin: auto;

    padding: 35px 0;

    display: flex;

    align-items: center;

    justify-content: space-between;

    gap: 30px;
}


.footer-content h3 {
    margin-bottom: 5px;

    font-size: 17px;
}


.footer-content p {
    color: #cbd5e1;

    font-size: 13px;
}


.footer-content > div:last-child {
    text-align: right;
}


/* ========================================
   RESPONSIVE - TABLET
======================================== */

@media (max-width: 950px) {

    .hero-container {
        grid-template-columns: 1fr;

        text-align: center;
    }


    .hero-content {
        margin: auto;
    }


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


    .hero-visual {
        max-width: 600px;

        margin: auto;

        width: 100%;
    }


    .concept-grid {
        grid-template-columns:
            repeat(2, 1fr);
    }


    .steps-container {
        grid-template-columns:
            repeat(3, 1fr);
    }

}


/* ========================================
   RESPONSIVE - MOBILE
======================================== */

@media (max-width: 750px) {

    .nav-container {
        flex-direction: column;

        padding:
            14px 0;
    }


    .nav-links {
        width: 100%;

        justify-content: center;

        gap: 15px;

        flex-wrap: wrap;
    }


    .nav-links a {
        font-size: 12px;
    }


    .hero {
        padding: 55px 0;
    }


    .hero h1 {
        font-size: 42px;
    }


    .network-flow {
        flex-wrap: wrap;
    }


    .connection {
        display: none;
    }


    .information-grid,
    .browser-grid {
        grid-template-columns: 1fr;
    }


    .steps-container {
        grid-template-columns:
            repeat(2, 1fr);
    }


    .comparison-card {
        grid-template-columns: 1fr;
    }


    .comparison-divider {
        padding: 10px;

        min-height: 40px;
    }


    .summary-card {
        align-items: flex-start;
    }


    .footer-content {
        flex-direction: column;

        text-align: center;
    }


    .footer-content > div:last-child {
        text-align: center;
    }

}


/* ========================================
   RESPONSIVE - SMALL MOBILE
======================================== */

@media (max-width: 480px) {

    .container {
        width: 92%;
    }


    .hero h1 {
        font-size: 35px;
    }


    .hero-content > p {
        font-size: 16px;
    }


    .hero-buttons {
        flex-direction: column;
    }


    .primary-button,
    .secondary-button {
        width: 100%;

        text-align: center;
    }


    .network-card {
        padding: 25px 15px;
    }


    .flow {
        flex-direction: column;
    }


    .flow-arrow {
        transform: rotate(90deg);
    }


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


    .steps-container {
        grid-template-columns: 1fr;
    }


    .overview-card,
    .info-card,
    .browser-card,
    .comparison-column {
        padding: 22px;
    }


    .url-parts div {
        flex-direction: column;

        align-items: flex-start;
    }


    .summary-card {
        flex-direction: column;
    }


    .section-heading h2 {
        font-size: 27px;
    }

}