:root {
    --header-height: 72px;
    --surface: #F5FAFE;
    --feature-image-size: 270px;
    --column-gutter: 15px;
    --hero-name-cycle: 6s;
    --text: #212121;
    --ink: #0a1a2e;
    --ink-light: #1e3a5f;
    --accent: #ffc200;
    --success: #28a745;
    --error: #dc3545;
    --timeline-dot: #474559;
}

   @font-face {
       font-family: 'Calibri';
       src: url('../fonts/calibri-regular.ttf') format('truetype');
       font-weight: 400;
       font-style: normal;
       font-display: swap;
   }

   @font-face {
       font-family: 'Calibri';
       src: url('../fonts/calibri-bold.ttf') format('truetype');
       font-weight: 700;
       font-style: normal;
       font-display: swap;
   }

   html, body {
       overflow-x: hidden;
       max-width: 100%;
   }

   * {
       font-family: 'Calibri', sans-serif;
   }

   body {
       font-family: 'Calibri', sans-serif;
       padding-top: var(--header-height);
   }

   ul {
       margin: 0;
       padding: 0;
   }

   ul li {
       list-style: none;
   }

   a {
       font-weight: normal;
       text-decoration: none !important;
       transition: all 0.4s ease;
   }

   a:hover {
       color: var(--accent) !important;
   }

   p {
       font-size: 16px;
       font-weight: 300;
       line-height: 1.5;
       color: var(--text);
   }

   strong, b {
       font-weight: 700;
   }

   h1, h2, h3, h4, h5 {
       font-weight: bold;
       letter-spacing: -1px;
   }

   h1 {
       color: var(--text);
       font-size: 2.8em;
       margin: 24px 0;
   }

   h2,
   h3 {
       color: var(--text);
       font-size: 25px;
   }

   h4 {
       color: var(--text);
       font-size: 20px;
   }

   .subtitle {
       color: var(--text);
       font-size: 20px;
       font-weight: bold;
       letter-spacing: -1px;
       line-height: 1.2;
       margin-bottom: 0.5rem;
   }

.project-info .img-fluid {
    width: var(--feature-image-size);
}

.about-image img,
.about-me .project-info img {
    width: var(--feature-image-size);
    max-width: 100%;
    aspect-ratio: 1 / 1;
    object-fit: contain;
}

.about-me .row {
    align-items: center;
}

section {
    padding-top: 3rem;
    padding-bottom: 3rem;
}

section.about {
    padding-top: 5rem;
}

.container {
    max-width: 1000px;
    margin-left: auto;
    margin-right: auto;
}

section.about .container {
    max-width: 1000px;
}

section.project .container {
    max-width: 1100px;
}

section.resume .container {
    max-width: 1100px;
}

section.contact .container {
    max-width: 1200px;
}

section.about .row,
section.project .row,
section.resume .row,
section.contact .row {
    justify-content: center;
}

.swiper-slide .row {
    justify-content: center;
}

.swiper-slide .row > [class*="col-"] {
    padding-left: 15px;
    padding-right: 15px;
}

   .color-text {
       color: var(--ink);
   }

   .navbar {
       position: fixed;
       background-color: var(--surface);
       top: 0;
       right: 0;
       left: 0;
       z-index: 999999;
       box-shadow: none;
   }

   .navbar.scrolled {
       box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
   }

   .navbar-brand {
       font-weight: bold;
   }

   .navbar-brand-icon {
       font-size: 40px;
   }

   @media (min-width: 992px) {
       .navbar-brand-icon {
           margin-left: 24px;
       }

       .navbar-collapse {
           margin-left: 30%;
       }
   }

   .navbar-expand-sm .navbar-nav .nav-link {
       padding: 0 20px;
       color: var(--ink);
   }

   .nav-link {
       font-weight: bold;
       font-size: 16px;
       overflow: hidden;
   }

   body {
       font-size: 16px;
   }

   td, th, li, span, label, input, textarea, select {
       font-size: 16px;
   }

   .nav-link span {
       position: relative;
       display: inline-block;
       transition: transform 0.3s;
   }

   .nav-link span:before {
       position: absolute;
       top: 100%;
       content: attr(data-hover);
       transform: translate3d(0, 0, 0);
   }

   .navbar-light .navbar-nav .nav-link:focus,
   .navbar-light .navbar-nav .nav-link:hover {
       color: var(--accent);
       font-weight: bold;
   }

   .navbar-light .navbar-nav .nav-link:focus span,
   .navbar-light .navbar-nav .nav-link:hover span {
       transform: translateY(-100%);
   }

   @media (hover: none) {
       .nav-link span {
           transition: none;
       }

       .nav-link span::before {
           display: none;
       }

       .navbar-light .navbar-nav .nav-link:focus span,
       .navbar-light .navbar-nav .nav-link:hover span {
           transform: none;
       }
   }

   .navbar-toggler {
       border: 0;
       padding: 0;
       width: 32px;
       height: 32px;
       line-height: 32px;
       outline: none;
       cursor: pointer;
       margin-right: 10px;
   }

   .navbar-toggler:focus {
       outline: none;
   }

   .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon:first-child {
       transform: rotate(45deg);
       top: 6px;
   }

   .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon:nth-child(2) {
       display: none;
   }

   .navbar-toggler[aria-expanded="true"] .navbar-toggler-icon:last-child {
       transform: rotate(-45deg);
       bottom: 1px;
   }

   .navbar-toggler .navbar-toggler-icon {
       background: var(--text);
       display: block;
       width: 100%;
       height: 2px;
       margin: 5px 0;
       transition: all 0.4s ease;
       position: relative;
   }

section.about > .container > .row {
    justify-content: center;
    gap: 20px;
}

section.about .col-lg-7 {
    flex: 0 0 55%;
    max-width: 55%;
}

section.about .col-lg-5 {
    flex: 0 0 40%;
    max-width: 40%;
}

.social-icons {
    padding-top: 24px;
}

.social-icons a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    color: var(--ink);
    margin: 0 20px 0 0;
    text-decoration: none;
    transition: transform 250ms ease-out, color 250ms ease-out;
}

.about-text table td {
    padding: 4px 0;
}

.about-text table td:first-child {
    width: 32px;
}

.social-icons a svg {
    width: 26px;
    height: 26px;
    fill: currentColor;
    display: block;
}

.social-icons a:hover {
    color: var(--accent);
    transform: translateY(-5px);
}

   .custom-btn {
       display: inline-block;
       width: auto;
       height: 40px;
       padding: 0 20px;
       font-size: 16px;
       font-weight: bold;
       line-height: 38px;
       text-align: center;
       white-space: nowrap;
       background: linear-gradient(90deg, var(--ink-light), var(--ink));
       color: #ffffff;
       border: none;
       border-radius: 10px;
       box-shadow: 0 4px 12px rgba(14, 30, 59, 0.2);
       transition: all 0.3s ease;
       cursor: pointer;
   }

   .custom-btn:hover {
       background: linear-gradient(90deg, var(--ink), var(--ink-light));
       color: #ffffff !important;
       transform: scale(1.03);
       box-shadow: 0 6px 16px rgba(14, 30, 59, 0.3);
   }

   .animated {
       position: relative;
       font-size: 28px;
   }

   .animated .mr-2 {
       font-size: 28px;
   }

   .animated-info {
       display: inline-block;
       vertical-align: top;
       min-width: 280px;
       position: relative;
   }

   .animated-item {
       color: var(--accent);
       font-size: 28px;
       line-height: inherit;
       display: block;
       opacity: 0;
       overflow: hidden;
       position: absolute;
       top: 0;
       right: 0;
       left: 0;
       animation: BottomTotop var(--hero-name-cycle) linear infinite;
   }

   .animated-item:nth-child(2) {
       animation-delay: calc(var(--hero-name-cycle) / 2);
   }

   @keyframes BottomTotop {
       0% { opacity: 0; transform: translateY(8px); }
       4% { opacity: 1; transform: translateY(0); }
       48% { opacity: 1; transform: translateY(0); }
       54% { opacity: 0; transform: translateY(-8px); }
       100% { opacity: 0; transform: translateY(-8px); }
   }

   .timeline-wrapper {
       position: relative;
       padding: 22px 0;
   }

   .timeline-wrapper:last-child:before {
       height: 0;
   }

   .timeline-wrapper:before {
       content: "";
       background: var(--timeline-dot);
       width: 3px;
       height: 100%;
       position: absolute;
       left: 38px;
   }

   .timeline-yr {
       background: var(--timeline-dot);
       border-radius: 100%;
       position: absolute;
       width: 75px;
       height: 75px;
       line-height: 75px;
       text-align: center;
   }

   .timeline-yr span {
       color: #ffffff;
       font-size: 16px;
       font-weight: bold;
       display: block;
       line-height: 75px;
   }

   .timeline-info {
       display: inline-block;
       vertical-align: top;
       max-width: 432px;
       margin-left: 6em;
   }

   .swiper {
       width: 100%;
       padding-bottom: 30px;
       position: relative;
   }

   .swiper-slide {
       display: flex;
       justify-content: center;
       align-items: center;
       background: #fff;
       border-radius: 10px;
       transition: transform 0.2s ease;
   }

   .swiper-slide:hover {
       transform: translateY(-5px);
   }

   .swiper-slide .container {
       padding: 20px;
   }

   .swiper-slide img {
       width: 100%;
       height: auto;
       border-radius: 8px;
       object-fit: cover;
       max-height: 300px;
   }

   .swiper-slide .text-left {
       padding: 20px;
   }

   .swiper-slide h3 {
       font-size: 25px;
       margin-bottom: 10px;
   }

   .swiper-slide .subtitle {
       font-size: 20px;
       color: var(--text);
       line-height: 1.2;
       margin-bottom: 15px;
   }

   .swiper-slide p {
       font-size: 16px;
       line-height: 1.6;
       color: var(--text);
   }

   .swiper-slide .btn {
       margin-top: 15px;
   }

   #certificate .swiper-slide .color-text,
   #certificate .swiper-slide .text-left {
       text-align: left;
   }

   #certificate .swiper-slide .color-text h3,
   #certificate .swiper-slide .color-text h5,
   #certificate .swiper-slide .color-text table,
   #certificate .swiper-slide .color-text a {
       text-align: left;
   }

   .swiper-pagination {
       position: relative;
       bottom: 10px;
   }

   .swiper-pagination-bullet {
       width: 10px;
       height: 10px;
       background: #D6D6D6;
       opacity: 0.7;
       transition: all 0.3s ease;
   }

   .swiper-pagination-bullet-active {
       background: var(--accent);
       opacity: 1;
   }

   .swiper-button-prev,
   .swiper-button-next {
       background-color: var(--accent);
       color: #fff;
       width: 45px;
       height: 45px;
       border-radius: 50%;
       box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
       top: 80%;
       transform: translateY(-50%);
       z-index: 10;
       transition: all 0.3s ease;
   }

   .swiper-button-prev {
       left: 10px;
   }

   .swiper-button-next {
       right: 10px;
   }

   .swiper-button-prev:hover,
   .swiper-button-next:hover {
       background-color: #e0a800;
       transform: scale(1.1) translateY(-50%);
   }

   .responsive-video {
       width: 100%;
       max-width: 500px;
       height: auto;
       border-radius: 10px;
   }

   .contact-form h2 {
       margin-bottom: 0;
       padding-left: var(--column-gutter);
       padding-right: var(--column-gutter);
   }

   .contact-form .form-control {
       background: transparent;
       border-radius: 2px;
       outline: none;
       box-shadow: none;
       font-weight: bold;
       margin: 16px 0;
   }

   .contact-form .form-control:not(textarea) {
       height: 48px;
   }

   .contact-form .form-control:hover,
   .contact-form .form-control:focus {
       border-color: var(--accent);
   }

   .contact-form button[type="submit"] {
       width: 100%;
       height: 48px;
       font-size: 16px;
       line-height: 48px;
       padding: 0 24px;
   }

   .contact-form button[type="submit"]:disabled {
       background: #ccc !important;
       cursor: not-allowed;
       transform: none !important;
       box-shadow: none !important;
   }

   #formMessage {
       font-size: 15px;
       margin-top: 10px;
       text-align: center;
   }

   #countdown {
       font-weight: normal;
       opacity: 0.8;
   }

   .form-message-success {
       color: var(--success);
       font-weight: bold;
   }

   .form-message-error {
       color: var(--error);
       font-weight: bold;
   }

   .footer {
       background-color: var(--surface);
       height: var(--header-height);
       display: flex;
       align-items: center;
   }

   .copyright-text {
       font-size: 16px;
       font-weight: normal;
       display: block;
       margin-bottom: 0;
   }

   a {
       font-size: 16px;
   }

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

.container {
    padding-left: 10px;
    padding-right: 10px;
}

.row {
    margin-left: 0;
    margin-right: 0;
}

.row > [class*="col-"] {
    padding-left: 15px;
    padding-right: 15px;
}

@media (max-width: 991px) {

    section {
        padding-top: 1.5rem;
        padding-bottom: 1.5rem;
    }

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

    .container,
    section.about .container,
    section.project .container,
    section.resume .container,
    section.contact .container {
        max-width: 100%;
        padding-left: 12px;
        padding-right: 12px;
    }

    .swiper-slide .container {
        padding: 15px;
    }

    .swiper-slide img {
        max-height: 250px;
    }

    .swiper-button-prev,
    .swiper-button-next {
        width: 40px;
        height: 40px;
    }

    .swiper-button-prev::after,
    .swiper-button-next::after {
        font-size: 18px;
        font-weight: bold;
    }
}

@media (max-width: 768px) {

    section {
        padding-top: 1.25rem;
        padding-bottom: 1.25rem;
    }

    section.about {
        padding-top: 2.5rem;
    }

    section.about .col-lg-7,
    section.about .col-lg-5 {
        flex: 0 0 100%;
        max-width: 100%;
    }

    section.about > .container > .row {
        flex-direction: column-reverse;
        gap: 0;
    }

    section.about .row {
        text-align: left;
    }

    section.about .about-text {
        text-align: left;
        margin-left: 1rem;
    }

    section.about .about-text table {
        margin: 0;
        text-align: left;
    }

    section.about .social-icons {
        justify-content: flex-start;
        display: flex;
    }

    section.about .custom-btn-group {
        text-align: left;
    }

    section.about .about-image {
        text-align: center;
        margin-bottom: 25px;
    }

    section.about .about-image img {
        max-width: 220px;
        margin: 0 auto;
    }

    .animated {
        justify-content: flex-start;
        flex-wrap: wrap;
    }

    .animated-info {
        min-width: 100%;
        text-align: left;
    }

    .animated,
    .animated .mr-2,
    .animated-item {
        font-size: 24px;
    }

    .animated-info .animated-item {
        font-size: 26px;
    }

    .animated-item {
        text-align: left;
    }

    .swiper-slide .row {
        flex-direction: column;
        text-align: center;
    }

    .swiper-slide .text-left {
        padding: 15px 10px;
    }

    .swiper-slide img {
        max-height: 200px;
        margin: 0 auto;
    }

    .swiper-button-prev,
    .swiper-button-next {
        display: none;
    }

    .project .project-info {
        text-align: center;
        margin-bottom: 20px;
    }

    .about-me .project-info {
        display: none;
    }

    .about-me .text-left.mt-4,
    .about-me .mt-4 {
        margin-top: 0 !important;
    }

    .about-me p.color-text,
    #project .swiper-slide p,
    #hackathon .swiper-slide p,
    #certificate .swiper-slide p {
        text-align: justify;
        -webkit-hyphens: auto;
        -ms-hyphens: auto;
        hyphens: auto;
    }

    section.resume .row {
        flex-direction: column;
    }

    section.resume .col-lg-6 {
        flex: 0 0 100%;
        max-width: 100%;
        margin-bottom: 2rem;
    }

    section.resume .col-lg-6:last-child {
        margin-bottom: 0;
    }

    section.resume h2 {
        text-align: center;
    }

    section.resume .timeline-info h3 {
        text-align: left;
    }

    .timeline-info {
        max-width: calc(100% - 90px);
        margin-left: 5em;
    }

    .timeline-yr {
        width: 60px;
        height: 60px;
        line-height: 60px;
    }

    .timeline-yr span {
        font-size: 15px;
        line-height: 60px;
    }

    .timeline-wrapper:before {
        left: 28px;
    }

    section.contact .row {
        flex-direction: column;
    }

    section.contact .col-lg-8 {
        flex: 0 0 100%;
        max-width: 100%;
    }

    .contact-form h2 {
        text-align: center;
        padding-left: 0;
        padding-right: 0;
    }

    h2,
    h3 {
        font-size: 1.5em;
    }

    p {
        font-size: 16px;
    }

    .responsive-video {
        max-width: 100%;
        height: auto;
    }
}

@media (max-width: 576px) {

    section {
        padding-top: 1rem;
        padding-bottom: 1rem;
    }

    section.about {
        padding-top: 2rem;
    }

    .container,
    section .container {
        padding-left: 10px;
        padding-right: 10px;
    }

    section.about .about-image img {
        max-width: 180px;
    }

    .animated-info {
        min-width: 200px;
    }

    .animated,
    .animated .mr-2,
    .animated-item {
        font-size: 20px;
    }

    .animated-info .animated-item {
        font-size: 22px;
    }

    .timeline-info {
        margin-left: 4.5em;
        max-width: calc(100% - 80px);
    }

    .timeline-yr {
        width: 50px;
        height: 50px;
        line-height: 50px;
    }

    .timeline-yr span {
        font-size: 15px;
        line-height: 50px;
    }

    .timeline-wrapper:before {
        left: 23px;
    }

    .timeline-info h3 {
        font-size: 1.1rem;
    }

    .timeline-info .subtitle {
        font-size: 0.95rem;
    }

    .timeline-info table td {
        font-size: 15px;
    }

    .project .project-info img,
    .swiper-slide img {
        max-width: 100%;
        max-height: 180px;
    }

    .swiper-slide h3 {
        font-size: 1.3em;
    }

    .swiper-slide .subtitle {
        font-size: 0.95em;
    }

    .swiper-slide p {
        font-size: 15px;
    }

    .contact-form {
        padding: 0;
    }

    .social-icons a {
        margin: 0 12px 0 0;
    }

    .social-icons a svg {
        width: 24px;
        height: 24px;
    }

    h2,
    h3 {
        font-size: 1.3em;
    }

    p {
        font-size: 15px;
    }

    .small-text {
        font-size: 15px;
        padding: 6px 12px;
    }

    .navbar-collapse {
        background: var(--surface);
        padding: 15px;
        margin-top: 10px;
        border-radius: 8px;
        box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    }

    .navbar-expand-sm .navbar-nav .nav-link {
        padding: 10px 0;
    }

    .nav-link span::before {
        display: none;
    }

    .navbar-light .navbar-nav .nav-link:focus span,
    .navbar-light .navbar-nav .nav-link:hover span {
        transform: none;
    }

    .responsive-video {
        max-width: 100%;
        height: 200px;
    }
}

@media (max-width: 400px) {
    .row > [class*="col-"] {
        padding-left: 0;
        padding-right: 0;
    }

    .swiper {
        padding-bottom: 0;
    }

    .timeline-info {
        margin-left: 3.8em;
        max-width: calc(100% - 65px);
    }

    .timeline-yr {
        width: 42px;
        height: 42px;
        line-height: 42px;
    }

    .timeline-yr span {
        font-size: 15px;
        line-height: 42px;
    }

    .timeline-wrapper:before {
        left: 19px;
    }

    .timeline-info h3 {
        font-size: 1rem;
    }

    .timeline-info .subtitle {
        font-size: 15px;
    }

    .timeline-info table td {
        font-size: 15px;
    }

    .animated,
    .animated .mr-2,
    .animated-item {
        font-size: 18px;
    }

    .animated-info .animated-item {
        font-size: 20px;
    }

    h2,
    h3 {
        font-size: 1.2em;
    }

    p {
        font-size: 15px;
    }

}


   :focus-visible {
       outline: 3px solid var(--accent);
       outline-offset: 2px;
   }

   .custom-btn:focus-visible,
   .social-icons a:focus-visible {
       outline: 3px solid var(--ink);
       outline-offset: 3px;
   }

   @media (prefers-reduced-motion: reduce) {
       *,
       *::before,
       *::after {
           animation-duration: 0.01ms !important;
           animation-iteration-count: 1 !important;
           transition-duration: 0.01ms !important;
           scroll-behavior: auto !important;
       }

       .animated-item {
           opacity: 1;
       }

       .animated-item:nth-child(2) {
           display: none;
       }
   }