/* =========================================================
   HRTOS INTERNATIONAL WEBSITE
   ---------------------------------------------------------
   File        : style.css
   Project     : HRTOS
   Website     : https://en.hrtos.com/
   Version     : 2.0.0
   Description : Global design system and component styles
   Copyright   : HRTOS Project
   ========================================================= */


/* =========================================================
   01. CSS VARIABLES
   ========================================================= */

:root {
    /* Brand Colors */
    --primary: #2878e5;
    --primary-dark: #155fc2;
    --primary-light: #eaf2ff;

    /* Background */
    --bg-body: #ffffff;
    --bg-light: #f6f8fb;
    --bg-dark: #101a2b;
    --bg-card: #ffffff;

    /* Text */
    --text-primary: #172338;
    --text-secondary: #64748b;
    --text-light: #aab7ca;
    --text-white: #ffffff;

    /* Borders */
    --border: #e5eaf1;
    --border-dark: #29364a;

    /* Accent */
    --accent: #36a3ff;
    --success: #16a36a;

    /* Typography */
    --font-main:
        "Inter",
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        sans-serif;

    --font-code:
        "SFMono-Regular",
        Consolas,
        "Liberation Mono",
        monospace;

    /* Layout */
    --container-width: 1200px;
    --header-height: 76px;

    /* Radius */
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 18px;

    /* Shadows */
    --shadow-sm:
        0 2px 8px rgba(16, 36, 64, 0.05);

    --shadow-md:
        0 8px 28px rgba(16, 36, 64, 0.08);

    --shadow-lg:
        0 18px 50px rgba(16, 36, 64, 0.12);

    /* Transition */
    --transition:
        all 0.25s ease;
}


/* =========================================================
   02. RESET
   ========================================================= */

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

html {
    scroll-behavior: smooth;
    scroll-padding-top: 90px;
}

body {
    font-family: var(--font-main);
    font-size: 16px;
    line-height: 1.75;
    color: var(--text-primary);
    background: var(--bg-body);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.menu-open {
    overflow: hidden;
}

img {
    display: block;
    max-width: 100%;
    height: auto;
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition);
}

button,
input,
textarea,
select {
    font: inherit;
}

button {
    cursor: pointer;
}

ul,
ol {
    padding-left: 22px;
}

::selection {
    background: var(--primary);
    color: #ffffff;
}


/* =========================================================
   03. GLOBAL LAYOUT
   ========================================================= */

.container {
    width: min(
        var(--container-width),
        calc(100% - 48px)
    );
    margin: 0 auto;
}

.section {
    position: relative;
    padding: 100px 0;
    background: var(--bg-body);
}

.section-light {
    background: var(--bg-light);
}

.section-dark {
    color: var(--text-white);
    background: var(--bg-dark);
}

.section-dark p {
    color: var(--text-light);
}

.section-dark h2,
.section-dark h3 {
    color: var(--text-white);
}

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

.section-heading {
    max-width: 760px;
    margin: 0 auto 55px;
    text-align: center;
}

.section-heading h2 {
    margin-bottom: 18px;
}

.section-heading p {
    margin-top: 10px;
    color: var(--text-secondary);
    font-size: 17px;
}

.section-dark .section-heading p {
    color: var(--text-light);
}


/* =========================================================
   04. TYPOGRAPHY
   ========================================================= */

h1,
h2,
h3,
h4,
h5,
h6 {
    color: var(--text-primary);
    font-weight: 700;
    line-height: 1.25;
    letter-spacing: -0.035em;
}

h1 {
    font-size: clamp(42px, 6vw, 68px);
}

h2 {
    font-size: clamp(30px, 4vw, 42px);
}

h3 {
    font-size: 21px;
}

h4 {
    font-size: 17px;
}

p {
    color: var(--text-secondary);
}

.eyebrow {
    display: inline-block;
    margin-bottom: 18px;
    color: var(--primary);
    font-size: 12px;
    font-weight: 800;
    letter-spacing: 0.16em;
    text-transform: uppercase;
}

.text-link {
    display: inline-block;
    margin-top: 18px;
    color: var(--primary);
    font-weight: 650;
}

.text-link:hover {
    color: var(--primary-dark);
    transform: translateX(4px);
}


/* =========================================================
   05. HEADER
   ========================================================= */

.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    width: 100%;
    height: var(--header-height);
    background: rgba(255, 255, 255, 0.96);
    border-bottom: 1px solid var(--border);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 100%;
    gap: 24px;
}

.site-header.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-sm);
}

.logo {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
    font-size: 25px;
    font-weight: 800;
    letter-spacing: -0.05em;
    color: var(--text-primary);
}

.logo img {
    width: 36px;
    height: 36px;
    object-fit: contain;
}

.main-nav {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 20px;
}

.main-nav a {
    position: relative;
    padding: 8px 0;
    color: #526176;
    font-size: 13px;
    font-weight: 600;
    white-space: nowrap;
}

.main-nav a:hover,
.main-nav a.active {
    color: var(--primary);
}

.main-nav a::after {
    position: absolute;
    right: 0;
    bottom: 0;
    left: 0;
    height: 2px;
    content: "";
    background: var(--primary);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.25s ease;
}

.main-nav a:hover::after,
.main-nav a.active::after {
    transform: scaleX(1);
}

.header-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 10px 19px;
    border-radius: var(--radius-sm);
    background: var(--primary);
    color: #ffffff;
    font-size: 13px;
    font-weight: 700;
    white-space: nowrap;
}

.header-cta:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
}


/* =========================================================
   06. HERO
   ========================================================= */

.page-hero {
    position: relative;
    display: flex;
    align-items: center;
    min-height: 550px;
    overflow: hidden;
    padding: 110px 0;
    color: #ffffff;
    background:
        radial-gradient(
            ellipse at 80% 20%,
            rgba(40, 120, 229, 0.27),
            transparent 45%
        ),
        linear-gradient(
            125deg,
            #101a2b 0%,
            #152945 60%,
            #10233c 100%
        );
}

.page-hero::before {
    position: absolute;
    top: -200px;
    right: -150px;
    width: 600px;
    height: 600px;
    border: 1px solid rgba(255,255,255,0.08);
    border-radius: 50%;
    content: "";
    box-shadow:
        0 0 0 70px rgba(255,255,255,0.02),
        0 0 0 140px rgba(255,255,255,0.015);
    pointer-events: none;
}

.page-hero::after {
    position: absolute;
    right: 8%;
    bottom: 10%;
    width: 250px;
    height: 250px;
    border: 1px solid rgba(54,163,255,0.18);
    border-radius: 50%;
    content: "";
    pointer-events: none;
}

.page-hero .container {
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 850px;
}

.page-hero h1 {
    margin-bottom: 25px;
    color: #ffffff;
    letter-spacing: -0.055em;
}

.page-hero .eyebrow {
    color: #65b7ff;
}

.hero-description {
    max-width: 680px;
    color: #c1cee0;
    font-size: 18px;
    line-height: 1.85;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    margin-top: 35px;
}


/* =========================================================
   07. BUTTONS
   ========================================================= */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 48px;
    padding: 12px 25px;
    border: 1px solid transparent;
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 700;
    transition: var(--transition);
}

.btn-primary {
    background: var(--primary);
    color: #ffffff;
}

.btn-primary:hover {
    background: var(--primary-dark);
    box-shadow: 0 8px 20px rgba(40,120,229,0.25);
    transform: translateY(-3px);
}

.btn-secondary {
    border-color: rgba(255,255,255,0.3);
    color: #ffffff;
    background: transparent;
}

.btn-secondary:hover {
    border-color: #ffffff;
    background: rgba(255,255,255,0.08);
    transform: translateY(-3px);
}

.section-light .btn-secondary {
    border-color: var(--border);
    color: var(--text-primary);
}

.section-light .btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
}


/* =========================================================
   08. CONTENT CARDS
   ========================================================= */

.content-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 25px;
}

.content-card {
    position: relative;
    padding: 34px 30px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: var(--bg-card);
    box-shadow: var(--shadow-sm);
    transition: var(--transition);
}

.content-card:hover {
    border-color: rgba(40,120,229,0.35);
    box-shadow: var(--shadow-md);
    transform: translateY(-6px);
}

.card-number {
    margin-bottom: 22px;
    color: var(--primary);
    font-family: var(--font-code);
    font-size: 28px;
    font-weight: 700;
}

.content-card h3 {
    margin-bottom: 14px;
}

.content-card p {
    font-size: 14px;
    line-height: 1.85;
}


/* =========================================================
   09. PHILOSOPHY GRID
   ========================================================= */

.philosophy-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1px;
    overflow: hidden;
    border: 1px solid var(--border-dark);
    border-radius: var(--radius-md);
    background: var(--border-dark);
}

.philosophy-item {
    min-height: 190px;
    padding: 35px;
    background: #152238;
    transition: var(--transition);
}

.philosophy-item:hover {
    background: #1b2d48;
}

.philosophy-item h3 {
    margin-bottom: 15px;
    color: #ffffff;
}

.philosophy-item p {
    font-size: 14px;
    line-height: 1.85;
}


/* =========================================================
   10. SCOPE GRID
   ========================================================= */

.scope-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 22px;
}

.scope-item {
    position: relative;
    padding: 30px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: #ffffff;
    transition: var(--transition);
}

.scope-item:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-md);
    transform: translateY(-5px);
}

.scope-item h3 {
    margin-bottom: 12px;
}

.scope-item p {
    font-size: 14px;
    line-height: 1.8;
}

.scope-item .text-link {
    font-size: 13px;
}


/* =========================================================
   11. TIMELINE
   ========================================================= */

.timeline {
    position: relative;
    max-width: 900px;
    margin: 0 auto;
    padding-left: 135px;
}

.timeline::before {
    position: absolute;
    top: 10px;
    bottom: 10px;
    left: 92px;
    width: 2px;
    content: "";
    background: linear-gradient(
        to bottom,
        var(--primary),
        rgba(40,120,229,0.12)
    );
}

.timeline-item {
    position: relative;
    padding-bottom: 65px;
}

.timeline-item:last-child {
    padding-bottom: 0;
}

.timeline-year {
    position: absolute;
    top: 0;
    left: -135px;
    width: 75px;
    color: var(--accent);
    font-family: var(--font-code);
    font-size: 20px;
    font-weight: 700;
    text-align: right;
}

.timeline-item::before {
    position: absolute;
    top: 8px;
    left: -49px;
    width: 12px;
    height: 12px;
    border: 3px solid var(--primary);
    border-radius: 50%;
    content: "";
    background: var(--bg-dark);
    box-shadow: 0 0 0 5px rgba(40,120,229,0.12);
}

.timeline-content {
    padding: 0 0 0 5px;
}

.timeline-content h3 {
    margin-bottom: 15px;
    color: #ffffff;
    font-size: 23px;
}

.timeline-content p {
    margin-bottom: 14px;
    color: #aab7ca;
    font-size: 15px;
}

.timeline-content ul {
    margin: 15px 0;
    color: #aab7ca;
    font-size: 14px;
}

.timeline-content li {
    margin-bottom: 8px;
    padding-left: 5px;
}


/* =========================================================
   12. ABOUT STATEMENT
   ========================================================= */

.about-statement {
    max-width: 850px;
    margin: 0 auto;
    padding: 55px;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    background: #ffffff;
    box-shadow: var(--shadow-sm);
}

.about-statement h2 {
    margin-bottom: 25px;
}

.about-statement p {
    margin-bottom: 18px;
    font-size: 16px;
    line-height: 1.9;
}

.about-statement a {
    color: var(--primary);
    font-weight: 600;
}

.about-statement a:hover {
    text-decoration: underline;
}


/* =========================================================
   13. CTA SECTION
   ========================================================= */

.cta-section {
    overflow: hidden;
    color: #ffffff;
    background:
        radial-gradient(
            circle at 85% 20%,
            rgba(54,163,255,0.2),
            transparent 40%
        ),
        linear-gradient(120deg, #11233d, #173c67);
}

.cta-content {
    max-width: 780px;
    margin: 0 auto;
    text-align: center;
}

.cta-content .eyebrow {
    color: #72c0ff;
}

.cta-content h2 {
    margin-bottom: 20px;
    color: #ffffff;
}

.cta-content p {
    color: #c2d1e5;
    font-size: 17px;
}

.cta-content .hero-actions {
    justify-content: center;
}


/* =========================================================
   14. FOOTER
   ========================================================= */

.site-footer {
    padding: 75px 0 25px;
    color: #ffffff;
    background: #0b1422;
}

.footer-main {
    display: grid;
    grid-template-columns: 1.7fr 1fr 1fr 1fr;
    gap: 45px;
    padding-bottom: 55px;
}

.footer-brand .logo {
    margin-bottom: 20px;
    color: #ffffff;
}

.footer-brand p {
    max-width: 300px;
    color: #8d9bb0;
    font-size: 14px;
    line-height: 1.85;
}

.footer-links {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
}

.footer-links h4 {
    margin-bottom: 8px;
    color: #ffffff;
}

.footer-links a {
    color: #8d9bb0;
    font-size: 13px;
}

.footer-links a:hover {
    color: #ffffff;
    transform: translateX(3px);
}

.footer-bottom {
    display: flex;
    justify-content: space-between;
    gap: 20px;
    padding-top: 22px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.footer-bottom p {
    color: #74839a;
    font-size: 12px;
}


/* =========================================================
   15. PAGE CONTENT / ARTICLE
   ========================================================= */

.page-content {
    max-width: 850px;
    margin: 0 auto;
}

.page-content h2 {
    margin: 45px 0 20px;
    font-size: 30px;
}

.page-content h3 {
    margin: 30px 0 15px;
}

.page-content p {
    margin-bottom: 18px;
    line-height: 1.9;
}

.page-content ul,
.page-content ol {
    margin: 20px 0;
    color: var(--text-secondary);
}

.page-content li {
    margin-bottom: 10px;
}

.page-content a {
    color: var(--primary);
}

.page-content a:hover {
    text-decoration: underline;
}


/* =========================================================
   16. CODE BLOCKS
   ========================================================= */

pre,
code {
    font-family: var(--font-code);
}

pre {
    overflow-x: auto;
    margin: 25px 0;
    padding: 25px;
    border: 1px solid #27364c;
    border-radius: var(--radius-md);
    background: #101a2b;
    color: #d8e5f5;
    font-size: 13px;
    line-height: 1.8;
}

code {
    padding: 3px 6px;
    border-radius: 4px;
    background: #eef3f9;
    color: #245ba0;
    font-size: 0.9em;
}

pre code {
    padding: 0;
    background: transparent;
    color: inherit;
}


/* =========================================================
   17. TABLES
   ========================================================= */

.table-wrapper {
    overflow-x: auto;
    margin: 30px 0;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}

table {
    width: 100%;
    border-collapse: collapse;
    background: #ffffff;
}

th,
td {
    padding: 15px 18px;
    border-bottom: 1px solid var(--border);
    text-align: left;
    font-size: 14px;
}

th {
    background: var(--bg-light);
    color: var(--text-primary);
    font-weight: 700;
}

td {
    color: var(--text-secondary);
}

tr:last-child td {
    border-bottom: none;
}


/* =========================================================
   18. FEATURE LIST
   ========================================================= */

.feature-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 20px;
}

.feature-item {
    padding: 25px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: #ffffff;
}

.feature-item h3 {
    margin-bottom: 12px;
}

.feature-item p {
    font-size: 14px;
}


/* =========================================================
   19. STATISTICS
   ========================================================= */

.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 20px;
}

.stat-item {
    padding: 28px 20px;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    background: #ffffff;
    text-align: center;
}

.stat-number {
    display: block;
    margin-bottom: 8px;
    color: var(--primary);
    font-family: var(--font-code);
    font-size: 34px;
    font-weight: 800;
}

.stat-label {
    color: var(--text-secondary);
    font-size: 13px;
}


/* =========================================================
   20. BADGES
   ========================================================= */

.badge {
    display: inline-flex;
    align-items: center;
    padding: 5px 11px;
    border-radius: 30px;
    background: var(--primary-light);
    color: var(--primary);
    font-size: 11px;
    font-weight: 700;
}

.badge-success {
    background: #e7f7ef;
    color: var(--success);
}

.badge-dark {
    background: #26364d;
    color: #ffffff;
}


/* =========================================================
   21. FORMS
   ========================================================= */

.form-group {
    margin-bottom: 22px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 650;
}

.form-control {
    display: block;
    width: 100%;
    padding: 13px 15px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    outline: none;
    background: #ffffff;
    color: var(--text-primary);
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(40,120,229,0.1);
}

textarea.form-control {
    min-height: 140px;
    resize: vertical;
}


/* =========================================================
   22. IMAGES
   ========================================================= */

.image-box {
    overflow: hidden;
    border-radius: var(--radius-md);
    background: var(--bg-light);
}

.image-box img {
    width: 100%;
    transition: transform 0.5s ease;
}

.image-box:hover img {
    transform: scale(1.04);
}

.hero-image {
    width: 100%;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.architecture-image {
    width: 100%;
    margin: 30px 0;
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
}


/* =========================================================
   23. READING PROGRESS
   ========================================================= */

.reading-progress {
    position: fixed;
    top: 0;
    left: 0;
    z-index: 9999;
    width: 0;
    height: 3px;
    background: var(--primary);
    transition: width 0.1s linear;
}


/* =========================================================
   24. MOBILE MENU BUTTON
   ========================================================= */

.menu-toggle {
    display: none;
    width: 42px;
    height: 42px;
    padding: 10px;
    border: 1px solid var(--border);
    border-radius: 8px;
    background: transparent;
    color: var(--text-primary);
    cursor: pointer;
}

.menu-toggle span {
    display: block;
    height: 2px;
    margin: 5px 0;
    background: currentColor;
    transition: all 0.25s ease;
}

.menu-toggle.active span:first-child {
    transform: translateY(7px) rotate(45deg);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:last-child {
    transform: translateY(-7px) rotate(-45deg);
}


/* =========================================================
   25. BACK TO TOP
   ========================================================= */

.back-to-top {
    position: fixed;
    right: 25px;
    bottom: 25px;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    width: 46px;
    height: 46px;
    border: none;
    border-radius: 50%;
    background: var(--primary);
    color: #ffffff;
    font-size: 24px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition);
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-4px);
}


/* =========================================================
   26. SCROLL REVEAL
   ========================================================= */

.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition:
        opacity 0.6s ease,
        transform 0.6s ease;
}

.reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}


/* =========================================================
   27. SECTION ACTION
   ========================================================= */

.section-action {
    margin-top: 40px;
    text-align: center;
}


/* =========================================================
   28. ACCESSIBILITY
   ========================================================= */

a:focus-visible,
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
    outline: 3px solid rgba(40,120,229,0.45);
    outline-offset: 3px;
}

.skip-link {
    position: absolute;
    top: -100px;
    left: 15px;
    z-index: 10000;
    padding: 12px 18px;
    border-radius: 6px;
    background: var(--primary);
    color: #ffffff;
}

.skip-link:focus {
    top: 15px;
}


/* =========================================================
   29. PRINT
   ========================================================= */

@media print {

    .site-header,
    .site-footer,
    .back-to-top,
    .reading-progress,
    .hero-actions {
        display: none !important;
    }

    body {
        color: #000000;
        background: #ffffff;
    }

    .section,
    .page-hero {
        padding: 25px 0;
        color: #000000;
        background: #ffffff;
    }

    h1,
    h2,
    h3,
    p {
        color: #000000 !important;
    }

    .reveal {
        opacity: 1;
        transform: none;
    }

}


/* =========================================================
   30. REDUCED MOTION
   ========================================================= */

@media (prefers-reduced-motion: reduce) {

    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }

    .reveal {
        opacity: 1;
        transform: none;
    }

}


/* =========================================================
   END OF HRTOS GLOBAL STYLESHEET
   ========================================================= */