@import url('https://fonts.googleapis.com/css2?family=Barlow:wght@500;700&display=swap');

:root {
    --blue: #6EC1E4;
    --blue-dark: #1A1D56;
    --blue-dark-2: #11133d;
    --white: #ffffff;
    --light: #f3f8fb;
    --grey: #647083;
    --line: #dce6ed;
    --bad: #c84c5a;
    --good: #188b68;
    --radius: 18px;
    --shadow: 0 12px 40px rgba(26, 29, 86, 0.10);
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--blue-dark);
    background: var(--white);
    font-family: Arial, Helvetica, sans-serif;
    line-height: 1.6;
}

h1,
h2,
h3,
h4,
button,
nav,
.eyebrow,
.criterion-code,
.card-icon,
.section-number,
.demo-label {
    font-family: 'Barlow', sans-serif;
    font-weight: 700;
}

h1,
h2,
h3,
p {
    margin-top: 0;
}

a {
    color: inherit;
}

code,
pre {
    font-family: Consolas, 'Courier New', monospace;
}

code {
    color: var(--blue-dark);
    background: #eaf4f8;
    padding: 0.1em 0.35em;
    border-radius: 5px;
}

pre {
    margin: 0;
    overflow-x: auto;
    color: #dce9ef;
    background: #11142e;
    border-radius: 12px;
    padding: 1rem;
    font-size: 0.82rem;
    line-height: 1.55;
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 20;
    background: rgba(255, 255, 255, 0.95);
    border-bottom: 1px solid var(--line);
    backdrop-filter: blur(14px);
}

.header-inner {
    width: min(1180px, calc(100% - 2rem));
    margin: 0 auto;
    min-height: 76px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 2rem;
}

.brand img {
    display: block;
    width: 132px;
    height: auto;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 1.6rem;
}

.main-nav a {
    text-decoration: none;
    font-size: 0.95rem;
}

.main-nav a:hover {
    color: #2c9bc8;
}

.menu-toggle {
    display: none;
    border: 0;
    background: transparent;
}

.hero {
    width: min(1180px, calc(100% - 2rem));
    margin: 0 auto;
    padding: 5rem 0 6rem;
    display: grid;
    gap: 3rem;
}

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

.eyebrow {
    margin-bottom: 0.6rem;
    color: #2c9bc8;
    letter-spacing: 0.12em;
    font-size: 0.78rem;
}

.hero h1 {
    margin-bottom: 1.3rem;
    font-size: clamp(2.7rem, 8vw, 5.8rem);
    line-height: 0.96;
    letter-spacing: -0.035em;
}

.hero h1 span {
    color: #2c9bc8;
}

.hero-text {
    max-width: 650px;
    color: var(--grey);
    font-size: 1.12rem;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.8rem;
    margin-top: 1rem;
}

.button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 0.7rem 1.1rem;
    border: 2px solid transparent;
    border-radius: 999px;
    cursor: pointer;
    text-decoration: none;
}

.button-primary {
    color: var(--white);
    background: var(--blue-dark);
}

.button-secondary {
    color: var(--blue-dark);
    border-color: var(--blue-dark);
    background: transparent;
}

.hero-demo {
    position: relative;
    overflow: hidden;
    padding: 0 0 1rem;
    border-radius: var(--radius);
    background: #11142e;
    box-shadow: var(--shadow);
    transform: rotate(1deg);
}

.browser-bar {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    min-height: 42px;
    padding: 0 1rem;
    color: #aeb7d1;
    background: #1d2042;
    font-size: 0.78rem;
}

.browser-bar span {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #58617d;
}

.browser-bar strong {
    margin-left: auto;
    margin-right: auto;
    font-family: Arial, Helvetica, sans-serif;
    font-weight: normal;
}

.hero-demo pre {
    border-radius: 0;
    padding: 1.3rem;
}

.demo-badge {
    display: inline-block;
    margin: 0 1rem;
    padding: 0.35rem 0.7rem;
    border: 1px solid rgba(110, 193, 228, 0.35);
    border-radius: 999px;
    color: var(--blue);
    font-family: 'Barlow', sans-serif;
    font-weight: 500;
    font-size: 0.8rem;
}

.section {
    width: min(1180px, calc(100% - 2rem));
    margin: 0 auto;
    padding: 5rem 0;
}

.intro {
    border-top: 1px solid var(--line);
}

.section-heading {
    display: grid;
    grid-template-columns: auto 1fr;
    gap: 1.3rem;
    align-items: start;
    margin-bottom: 2.5rem;
}

.section-number {
    display: grid;
    place-items: center;
    width: 50px;
    height: 50px;
    color: var(--blue-dark);
    background: var(--blue);
    border-radius: 14px;
    font-size: 1.2rem;
}

.section-heading h2 {
    max-width: 800px;
    margin-bottom: 0;
    font-size: clamp(2rem, 5vw, 3.7rem);
    line-height: 1;
    letter-spacing: -0.025em;
}

.intro-grid {
    display: grid;
    gap: 1rem;
}

.info-card {
    padding: 1.5rem;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--white);
    box-shadow: var(--shadow);
}

.card-icon {
    display: grid;
    place-items: center;
    width: 42px;
    height: 42px;
    margin-bottom: 1.1rem;
    color: var(--white);
    background: var(--blue-dark);
    border-radius: 12px;
}

.info-card h3 {
    margin-bottom: 0.4rem;
    font-size: 1.4rem;
}

.info-card p {
    margin-bottom: 0;
    color: var(--grey);
}

.criteria-section {
    padding-top: 3rem;
}

.section-dark {
    width: 100%;
    padding-left: max(1rem, calc((100% - 1180px) / 2));
    padding-right: max(1rem, calc((100% - 1180px) / 2));
    color: var(--white);
    background: var(--blue-dark);
}

.section-dark .section-number {
    color: var(--white);
    background: var(--blue);
}

.section-dark .section-heading .eyebrow {
    color: var(--blue);
}

.criteria-list {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.criterion {
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--white);
    color: var(--blue-dark);
}

.criterion-head {
    width: 100%;
    display: grid;
    grid-template-columns: 76px 1fr 30px;
    align-items: center;
    gap: 1rem;
    padding: 1.15rem 1.3rem;
    border: 0;
    background: transparent;
    color: inherit;
    text-align: left;
    cursor: pointer;
}

.criterion-head:hover {
    background: #f7fbfd;
}

.criterion-code {
    color: #2c9bc8;
    font-size: 0.85rem;
}

.criterion-title {
    font-size: 1.1rem;
}

.criterion-arrow {
    display: grid;
    place-items: center;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    color: var(--white);
    background: var(--blue-dark);
    font-size: 1.2rem;
    line-height: 1;
    transition: transform 0.2s ease;
}

.criterion.open .criterion-arrow {
    transform: rotate(45deg);
}

.criterion-body {
    display: none;
    padding: 0 1.3rem 1.5rem;
}

.criterion.open .criterion-body {
    display: block;
}

.rule {
    max-width: 900px;
    color: var(--grey);
}

.example-grid {
    display: grid;
    gap: 1rem;
    margin: 1.2rem 0;
}

.example {
    overflow: hidden;
    border: 1px solid var(--line);
    border-radius: 14px;
}

.example-label {
    padding: 0.65rem 0.85rem;
    font-family: 'Barlow', sans-serif;
    font-weight: 700;
    font-size: 0.85rem;
}

.example.bad .example-label {
    color: var(--bad);
    background: #fff2f3;
}

.example.good .example-label {
    color: var(--good);
    background: #edf9f5;
}

.example pre {
    border-radius: 0;
}

.why {
    margin: 1rem 0 0;
    padding: 0.9rem 1rem;
    border-left: 4px solid var(--blue);
    color: var(--grey);
    background: var(--light);
}

.image-weight-demo {
    display: grid;
    gap: 0.8rem;
    margin: 1.2rem 0;
}

.fake-image {
    min-height: 100px;
    display: flex;
    flex-direction: column;
    justify-content: end;
    padding: 1rem;
    border-radius: 14px;
    color: var(--white);
    background: linear-gradient(135deg, #5a7e91, #18244b);
}

.fake-image strong {
    font-family: 'Barlow', sans-serif;
    font-size: 1.5rem;
}

.fake-image span {
    font-family: 'Barlow', sans-serif;
    font-weight: 500;
}

.photo-medium {
    background: linear-gradient(135deg, #4e9cc1, #1a1d56);
}

.photo-heavy {
    background: linear-gradient(135deg, #7b4250, #20162e);
}

.format-row,
.mini-rules {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 1rem;
}

.format-row span,
.mini-rules span,
.tag {
    padding: 0.5rem 0.7rem;
    border: 1px solid var(--line);
    border-radius: 999px;
    color: var(--grey);
    background: var(--light);
    font-size: 0.85rem;
}

.file-tree {
    max-width: 600px;
    padding: 1.2rem;
    border-radius: 14px;
    color: #dce9ef;
    background: #11142e;
    font-family: Consolas, monospace;
}

.tree-file,
.tree-root {
    margin: 0.35rem 0;
}

.tree-file em {
    color: var(--blue);
}

.folder-example {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.7rem;
    padding: 1rem;
    border-radius: 14px;
    background: var(--light);
}

.font-demo {
    padding: 1.5rem;
    margin-bottom: 1rem;
    border-radius: 14px;
    background: var(--light);
}

.font-title {
    margin-bottom: 0.4rem;
    color: var(--blue-dark);
    font-family: 'Barlow', sans-serif;
    font-weight: 700;
    font-size: 2rem;
}

.font-demo p {
    margin-bottom: 0;
    color: var(--grey);
}

.semantic-map {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.semantic-map span {
    padding: 0.6rem 0.8rem;
    border-radius: 10px;
    color: var(--white);
    background: var(--blue-dark);
    font-family: Consolas, monospace;
}

.section-dark .criterion {
    border-color: rgba(255, 255, 255, 0.12);
}

.section-dark .criterion-head:hover {
    background: #20245f;
}

.section-dark .criterion-body {
    background: #fff;
}

.responsive-demo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 1.2rem;
}

.phone,
.desktop {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 130px;
    padding: 1rem;
    border: 2px solid var(--blue);
    border-radius: 14px;
    text-align: center;
}

.phone {
    width: 115px;
}

.desktop {
    width: 180px;
}

.responsive-demo span {
    font-size: 2rem;
}

.responsive-demo small {
    color: var(--grey);
}

.arrow {
    color: #2c9bc8;
    font-size: 1.8rem;
}

.layout-demo {
    display: grid;
    gap: 1rem;
    margin-bottom: 1.2rem;
}

.layout-demo > div {
    padding: 1rem;
    border-radius: 14px;
    background: var(--light);
}

.demo-label {
    display: block;
    margin-bottom: 0.6rem;
    color: #2c9bc8;
    font-size: 0.8rem;
}

.flex-box {
    display: flex;
    gap: 0.5rem;
}

.flex-box i,
.grid-box i {
    display: grid;
    place-items: center;
    width: 40px;
    height: 40px;
    color: var(--white);
    background: var(--blue-dark);
    border-radius: 8px;
    font-style: normal;
    font-family: 'Barlow', sans-serif;
    font-weight: 700;
}

.grid-box {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.5rem;
}

.layout-demo p {
    margin: 0.7rem 0 0;
    color: var(--grey);
    font-size: 0.9rem;
}

.checklist-section {
    padding-bottom: 6rem;
}

.progress-card {
    margin-bottom: 1.5rem;
    padding: 1.3rem;
    border-radius: var(--radius);
    background: var(--blue-dark);
    color: var(--white);
}

.progress-top {
    display: flex;
    align-items: end;
    justify-content: space-between;
    gap: 1rem;
    margin-bottom: 0.8rem;
}

.progress-top strong {
    display: block;
    font-family: 'Barlow', sans-serif;
    font-size: 1.4rem;
}

.progress-top button {
    border: 0;
    border-bottom: 1px solid var(--blue);
    padding: 0.2rem;
    color: var(--blue);
    background: transparent;
    cursor: pointer;
}

.progress-track {
    height: 10px;
    overflow: hidden;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.12);
}

.progress-track span {
    display: block;
    width: 0;
    height: 100%;
    border-radius: inherit;
    background: var(--blue);
    transition: width 0.25s ease;
}

.checklist-grid {
    display: grid;
    gap: 1rem;
}

.check-group {
    padding: 1.3rem;
    border: 1px solid var(--line);
    border-radius: var(--radius);
}

.check-group h3 {
    margin-bottom: 1rem;
}

.check-group label {
    display: flex;
    align-items: flex-start;
    gap: 0.65rem;
    margin: 0.65rem 0;
    color: var(--grey);
    cursor: pointer;
}

.check-group input {
    width: 18px;
    height: 18px;
    margin-top: 0.2rem;
    accent-color: var(--blue-dark);
}

.check-group label:has(input:checked) {
    color: var(--blue-dark);
    text-decoration: line-through;
    text-decoration-color: var(--blue);
}

.site-footer {
    width: min(1180px, calc(100% - 2rem));
    margin: 0 auto;
    padding: 2rem 0 3rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1rem;
    border-top: 1px solid var(--line);
}

.site-footer img {
    width: 105px;
}

.site-footer p {
    margin: 0.3rem 0 0;
    color: var(--grey);
    font-size: 0.85rem;
}

.back-top {
    text-decoration: none;
    font-family: 'Barlow', sans-serif;
    font-weight: 700;
}

@media screen and (min-width: 700px) {
    .hero {
        grid-template-columns: 1.05fr 0.95fr;
        align-items: center;
    }

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

    .example-grid {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }

    .image-weight-demo {
        grid-template-columns: repeat(3, 1fr);
    }

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

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

@media screen and (min-width: 900px) {
    .section {
        padding-top: 6rem;
        padding-bottom: 6rem;
    }

    .criterion-head {
        grid-template-columns: 90px 1fr 30px;
        padding: 1.2rem 1.5rem;
    }

    .criterion-body {
        padding: 0 1.5rem 1.8rem;
    }
}

@media screen and (max-width: 699px) {
    .menu-toggle {
        width: 42px;
        height: 42px;
        display: flex;
        flex-direction: column;
        justify-content: center;
        gap: 5px;
        padding: 8px;
        cursor: pointer;
    }

    .menu-toggle span:not(.sr-only) {
        display: block;
        width: 100%;
        height: 2px;
        background: var(--blue-dark);
    }

    .main-nav {
        position: absolute;
        top: 76px;
        left: 0;
        width: 100%;
        display: none;
        flex-direction: column;
        align-items: stretch;
        gap: 0;
        padding: 0.5rem 1rem 1rem;
        background: var(--white);
        border-bottom: 1px solid var(--line);
    }

    .main-nav.open {
        display: flex;
    }

    .main-nav a {
        padding: 0.75rem;
    }

    .criterion-head {
        grid-template-columns: 62px 1fr 30px;
    }

    .responsive-demo {
        gap: 0.5rem;
    }

    .desktop {
        width: 145px;
    }

    .site-footer {
        align-items: flex-start;
        flex-direction: column;
    }
}