/* ==========================================================================
   Design tokens
   ========================================================================== */

:root {
    /* Apple-style neutral palette */
    --bg: #fbfbfd;
    --bg-alt: #f5f5f7;
    --surface: rgba(255, 255, 255, 0.72);
    --surface-solid: #ffffff;
    --text: #1d1d1f;
    --text-secondary: #6e6e73;
    --accent: #0071e3;
    --accent-hover: #0077ed;
    --border: rgba(0, 0, 0, 0.08);
    --border-strong: rgba(0, 0, 0, 0.14);
    --shadow-color: rgba(0, 0, 0, 0.1);
    --nav-bg: rgba(251, 251, 253, 0.75);

    /* Ambient light behind the page — gives the glass materials something to blur.
       Without this, backdrop-filter has nothing but a flat color under it and reads as flat. */
    --ambient-1: radial-gradient(760px circle at 10% -8%, rgba(0, 113, 227, 0.20), transparent 62%);
    --ambient-2: radial-gradient(640px circle at 92% 8%, rgba(124, 92, 255, 0.16), transparent 60%);
    --ambient-3: radial-gradient(900px circle at 50% 105%, rgba(255, 149, 0, 0.09), transparent 60%);

    /* Shape system — one radius per role, used everywhere instead of ad hoc values */
    --radius-icon: 30%;
    --radius-pill: 980px;
    --radius-card: 1.25rem;

    /* Apple's signature "ease-out" motion curve — used everywhere instead of linear/ease */
    --ease-spring: cubic-bezier(0.32, 0.72, 0, 1);
    --ease-soft: cubic-bezier(0.16, 1, 0.3, 1);
    --duration-fast: 0.15s;
    --duration-base: 0.4s;
}

:root[data-theme="dark"] {
    --bg: #000000;
    --bg-alt: #1d1d1f;
    --surface: rgba(29, 29, 31, 0.72);
    --surface-solid: #1d1d1f;
    --text: #f5f5f7;
    --text-secondary: #86868b;
    --accent: #2997ff;
    --accent-hover: #4dabff;
    --border: rgba(255, 255, 255, 0.12);
    --border-strong: rgba(255, 255, 255, 0.2);
    --shadow-color: rgba(0, 0, 0, 0.4);
    --nav-bg: rgba(0, 0, 0, 0.68);
    --ambient-1: radial-gradient(760px circle at 10% -8%, rgba(41, 151, 255, 0.18), transparent 62%);
    --ambient-2: radial-gradient(640px circle at 92% 8%, rgba(150, 110, 255, 0.14), transparent 60%);
    --ambient-3: radial-gradient(900px circle at 50% 105%, rgba(41, 151, 255, 0.12), transparent 60%);
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --bg: #000000;
        --bg-alt: #1d1d1f;
        --surface: rgba(29, 29, 31, 0.72);
        --surface-solid: #1d1d1f;
        --text: #f5f5f7;
        --text-secondary: #86868b;
        --accent: #2997ff;
        --accent-hover: #4dabff;
        --border: rgba(255, 255, 255, 0.12);
        --border-strong: rgba(255, 255, 255, 0.2);
        --shadow-color: rgba(0, 0, 0, 0.4);
        --nav-bg: rgba(0, 0, 0, 0.68);
        --ambient-1: radial-gradient(760px circle at 10% -8%, rgba(41, 151, 255, 0.18), transparent 62%);
        --ambient-2: radial-gradient(640px circle at 92% 8%, rgba(150, 110, 255, 0.14), transparent 60%);
        --ambient-3: radial-gradient(900px circle at 50% 105%, rgba(41, 151, 255, 0.12), transparent 60%);
    }
}

/* ==========================================================================
   Base
   ========================================================================== */

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    font-optical-sizing: auto;
    line-height: 1.6;
    color: var(--text);
    background-color: var(--bg);
    background-image: var(--ambient-1), var(--ambient-2), var(--ambient-3);
    background-repeat: no-repeat;
    background-attachment: fixed;
    transition: background-color var(--duration-base) var(--ease-soft), color var(--duration-base) var(--ease-soft);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

section {
    scroll-margin-top: 84px;
}

h1, h2, h3, h4 {
    font-weight: 600;
}

/* Display type: tight leading, negative tracking — grows more negative with size */
.about-text h1 {
    font-size: clamp(2.25rem, 5vw, 3.5rem);
    line-height: 1.05;
    letter-spacing: -0.03em;
}

section > .container > h2 {
    font-size: clamp(1.75rem, 4vw, 2.5rem);
    line-height: 1.1;
    letter-spacing: -0.02em;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text);
}

/* Small text: slightly positive tracking for legibility, body copy near zero */
.project-tags span,
.github-repo-badge,
.timeline-date {
    letter-spacing: 0.01em;
}

/* ==========================================================================
   Navbar — translucent material, content scrolls underneath
   ========================================================================== */

.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background-color: transparent;
    backdrop-filter: blur(0px) saturate(180%);
    -webkit-backdrop-filter: blur(0px) saturate(180%);
    z-index: 1000;
    transition: background-color var(--duration-base) var(--ease-soft), backdrop-filter var(--duration-base) var(--ease-soft), -webkit-backdrop-filter var(--duration-base) var(--ease-soft), box-shadow var(--duration-base) var(--ease-soft);
}

/* Edge effect instead of a hard divider: the material only thickens once
   there's content sliding under it to separate from. */
.navbar.scrolled {
    background-color: var(--nav-bg);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    box-shadow: 0 8px 24px -16px var(--shadow-color);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.9rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
}

.logo img {
    height: 32px;
    width: auto;
    display: block;
}

.logo .logo-dark {
    display: none;
}

:root[data-theme="dark"] .logo .logo-light {
    display: none;
}

:root[data-theme="dark"] .logo .logo-dark {
    display: block;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .logo .logo-light {
        display: none;
    }

    :root:not([data-theme="light"]) .logo .logo-dark {
        display: block;
    }
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 1.75rem;
    list-style: none;
}

.nav-links a {
    position: relative;
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    transition: color var(--duration-fast) var(--ease-spring);
}

.nav-links a::after {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    bottom: -6px;
    height: 2px;
    background: var(--accent);
    border-radius: 2px;
    transform: scaleX(0);
    transform-origin: center;
    transition: transform var(--duration-base) var(--ease-spring);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text);
}

.nav-links a.active::after {
    transform: scaleX(1);
}

.social-icons {
    display: flex;
    align-items: center;
    gap: 1rem;
    margin-left: 0.5rem;
    padding-left: 1rem;
    border-left: 1px solid var(--border);
}

.social-icons a {
    color: var(--text-secondary);
    font-size: 1.1rem;
    transition: color var(--duration-fast) var(--ease-spring), transform var(--duration-fast) var(--ease-spring);
}

.social-icons a:hover {
    color: var(--accent);
    transform: translateY(-2px);
}

/* Theme toggle — small glass pill */
.theme-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px;
    height: 34px;
    border-radius: 50%;
    border: none;
    background: var(--surface-solid);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 4px 12px var(--shadow-color);
    color: var(--text);
    cursor: pointer;
    font-size: 0.95rem;
    margin-left: 0.75rem;
    transition: transform var(--duration-fast) var(--ease-spring), background-color var(--duration-fast) var(--ease-spring), box-shadow var(--duration-fast) var(--ease-spring);
}

.theme-toggle:hover {
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05), 0 6px 16px var(--shadow-color);
}

.theme-toggle:active,
.theme-toggle.is-pressed {
    transform: scale(0.9);
}

/* Language toggle — same glass pill language, shows the target language */
.lang-toggle {
    display: inline-flex;
    align-items: center;
    gap: 0.35rem;
    height: 34px;
    padding: 0 0.75rem;
    border-radius: var(--radius-pill);
    border: none;
    background: var(--surface-solid);
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 4px 12px var(--shadow-color);
    color: var(--text);
    text-decoration: none;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.02em;
    transition: transform var(--duration-fast) var(--ease-spring), box-shadow var(--duration-fast) var(--ease-spring);
}

.lang-toggle i {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.lang-toggle:hover {
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05), 0 6px 16px var(--shadow-color);
}

.lang-toggle:active,
.lang-toggle.is-pressed {
    transform: scale(0.93);
}

/* ==========================================================================
   Buttons — instant press feedback, never wait for release
   ========================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    border-radius: var(--radius-pill);
    font-weight: 500;
    font-size: 1rem;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: transform var(--duration-fast) var(--ease-spring), background-color var(--duration-fast) var(--ease-spring), box-shadow var(--duration-fast) var(--ease-spring);
}

.btn:active,
.btn.is-pressed {
    transform: scale(0.97);
}

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

.btn.primary:hover {
    background-color: var(--accent-hover);
}

.btn.secondary {
    background-color: var(--bg-alt);
    color: var(--text);
}

.btn.secondary:hover {
    background-color: var(--border);
}

.btn.small {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
    border-radius: 50%;
    width: 2.5rem;
    height: 2.5rem;
}

/* ==========================================================================
   About / hero
   ========================================================================== */

.about {
    padding: 9rem 0 5rem;
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 4rem;
    align-items: center;
}

.profile-section {
    display: flex;
    justify-content: center;
}

/* Squircle-ish rounding, in the spirit of Apple's app-icon superellipse */
.profile-image {
    width: 260px;
    height: 260px;
    border-radius: var(--radius-icon);
    overflow: hidden;
    box-shadow: 0 20px 50px var(--shadow-color);
    border: 1px solid var(--border);
}

.profile-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.subtitle {
    font-size: clamp(1.1rem, 2vw, 1.4rem);
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    letter-spacing: -0.01em;
}

.bio {
    font-size: 1.1rem;
    line-height: 1.75;
    color: var(--text);
    max-width: 60ch;
}

/* ==========================================================================
   Glass surface — shared by cards across the page
   ========================================================================== */

.preview-card,
.project-card,
.timeline-content,
.education-item,
.contact-card,
.cv-embed-wrapper {
    background-color: var(--surface);
    backdrop-filter: blur(20px) saturate(160%);
    -webkit-backdrop-filter: blur(20px) saturate(160%);
    border: none;
    border-radius: var(--radius-card);
    /* Contact shadow (tight, low-opacity) + ambient shadow (soft, diffuse) reads
       as a thicker, more physical surface than a single flat blur. */
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 12px 28px var(--shadow-color);
    transition: transform var(--duration-base) var(--ease-spring), box-shadow var(--duration-base) var(--ease-spring);
}

.preview-card:hover,
.project-card:hover,
.education-item:hover {
    transform: translateY(-6px);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05), 0 20px 44px var(--shadow-color);
}

/* ==========================================================================
   Social previews
   ========================================================================== */

.social-previews {
    padding: 2rem 0;
}

.preview-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1.5rem;
    margin-top: 1rem;
}

.preview-card {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.preview-header {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.preview-avatar {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    object-fit: cover;
    border: 1px solid var(--border);
}

.preview-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.2rem;
    color: var(--accent);
    background-color: var(--bg-alt);
    border-radius: 50%;
    border: 1px solid var(--border);
}

.preview-info {
    flex: 1;
    min-width: 0;
}

.preview-info h3 {
    font-size: 1.05rem;
    color: var(--text);
    margin: 0;
}

.preview-info p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin: 0.2rem 0 0;
}

.preview-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.7rem 1.1rem;
    background-color: var(--bg-alt);
    color: var(--text);
    text-decoration: none;
    border-radius: var(--radius-pill);
    border: 1px solid var(--border);
    font-weight: 500;
    font-size: 0.95rem;
    margin-top: auto;
    transition: transform var(--duration-fast) var(--ease-spring), background-color var(--duration-fast) var(--ease-spring), border-color var(--duration-fast) var(--ease-spring);
}

.preview-button i {
    color: var(--accent);
}

.preview-button:hover {
    background-color: var(--border);
    border-color: var(--border-strong);
}

.preview-button:active,
.preview-button.is-pressed {
    transform: scale(0.97);
}

/* ==========================================================================
   Projects
   ========================================================================== */

.projects {
    padding: 5rem 0;
}

.project-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(290px, 1fr));
    gap: 1.75rem;
    align-items: stretch;
}

.project-card {
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.project-image-preview {
    width: 100%;
    height: 200px;
    object-fit: cover;
    display: block;
    background: var(--bg-alt);
}

.project-card:hover .project-image-preview {
    transform: scale(1.04);
}

.project-image-preview {
    transition: transform var(--duration-base) var(--ease-spring);
}

.project-info {
    padding: 1.25rem 1.4rem 1.5rem;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    flex: 1;
}

.project-info h3 {
    font-size: 1.2rem;
    letter-spacing: -0.01em;
    color: var(--text);
}

.project-info p {
    color: var(--text-secondary);
    line-height: 1.6;
    font-size: 0.95rem;
}

.project-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-top: 0.25rem;
}

.project-tags span {
    background-color: var(--bg-alt);
    color: var(--text);
    padding: 0.25rem 0.7rem;
    border-radius: var(--radius-pill);
    font-size: 0.8rem;
    border: 1px solid var(--border);
}

.project-links {
    display: flex;
    gap: 0.75rem;
    margin-top: auto;
    padding-top: 0.75rem;
}

.project-links a {
    color: var(--text);
}

.github-more-repos-section {
    margin-top: 2.5rem;
}

.github-closing-text {
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}

.github-more-repos {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.6rem;
}

.github-repo-badge {
    display: inline-block;
    background: var(--surface-solid);
    color: var(--accent);
    font-size: 0.9rem;
    font-weight: 500;
    border-radius: var(--radius-pill);
    border: 1px solid var(--accent);
    padding: 0.5rem 0.9rem;
    text-decoration: none;
    transition: background-color var(--duration-fast) var(--ease-spring), color var(--duration-fast) var(--ease-spring), transform var(--duration-fast) var(--ease-spring);
}

.github-repo-badge:hover {
    background: var(--accent);
    color: #fff;
}

.github-repo-badge:active,
.github-repo-badge.is-pressed {
    transform: scale(0.96);
}

/* ==========================================================================
   Experience — timeline
   ========================================================================== */

.experience {
    padding: 5rem 0;
}

.timeline {
    position: relative;
    max-width: 800px;
    margin: 0 auto;
}

.timeline::before {
    content: '';
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    width: 2px;
    height: 100%;
    background-color: var(--border);
}

.timeline-item {
    position: relative;
    margin-bottom: 2.5rem;
}

.timeline-content {
    position: relative;
    width: calc(50% - 2rem);
    padding: 1.5rem;
}

.timeline-item:nth-child(odd) .timeline-content {
    margin-left: auto;
}

.timeline-content::before {
    content: '';
    position: absolute;
    top: 1.75rem;
    width: 0.85rem;
    height: 0.85rem;
    background-color: var(--accent);
    border-radius: 50%;
    box-shadow: 0 0 0 4px var(--bg);
}

.timeline-item:nth-child(odd) .timeline-content::before { left: -2.45rem; }
.timeline-item:nth-child(even) .timeline-content::before { right: -2.45rem; }

.timeline-content h3 {
    font-size: 1.15rem;
    letter-spacing: -0.01em;
    margin-bottom: 0.3rem;
    color: var(--text);
}

.timeline-content h4 {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.4rem;
}

.timeline-date {
    font-size: 0.85rem;
    color: var(--accent);
    font-weight: 500;
}

/* ==========================================================================
   Education
   ========================================================================== */

.education {
    padding: 5rem 0;
}

.education-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1.5rem;
    max-width: 800px;
    margin: 0 auto;
}

.education-item {
    padding: 1.75rem;
}

.education-item h3 {
    font-size: 1.15rem;
    letter-spacing: -0.01em;
    margin-bottom: 0.4rem;
    color: var(--text);
}

.education-item .degree {
    color: var(--text-secondary);
    margin-bottom: 0.4rem;
}

.education-item .date {
    color: var(--accent);
    font-weight: 500;
    font-size: 0.9rem;
}

/* ==========================================================================
   Contact
   ========================================================================== */

.contact {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 5rem 0;
}

.contact-card {
    padding: 3rem 2.5rem;
    max-width: 420px;
    width: 100%;
    margin: 0 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
}

.contact-divider i {
    font-size: 2rem;
    color: var(--accent);
    margin-bottom: 1rem;
}

.contact-title {
    font-size: clamp(1.6rem, 3vw, 2rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: 0.75rem;
    color: var(--text);
}

.contact-desc {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 2rem;
}

.contact-btn {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    font-weight: 600;
    font-size: 1.05rem;
    padding: 0.9rem 2.2rem;
    border: none;
    border-radius: var(--radius-pill);
    cursor: pointer;
    text-decoration: none;
    transition: transform var(--duration-fast) var(--ease-spring), background-color var(--duration-fast) var(--ease-spring);
}

.contact-btn:hover {
    background: var(--accent-hover);
}

.contact-btn:active,
.contact-btn.is-pressed {
    transform: scale(0.97);
}

/* ==========================================================================
   CV
   ========================================================================== */

.cv-section {
    padding: 5rem 0 4rem;
}

.cv-title {
    text-align: center;
    font-size: clamp(1.6rem, 3vw, 2rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text);
    margin-bottom: 2rem;
}

.cv-actions {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2.5rem;
    flex-wrap: wrap;
}

.cv-btn {
    font-size: 1rem;
    font-weight: 600;
    padding: 0.85rem 2rem;
    border-radius: var(--radius-pill);
    border: none;
    background: var(--accent);
    color: #fff;
    text-decoration: none;
    display: inline-block;
    cursor: pointer;
    transition: transform var(--duration-fast) var(--ease-spring), background-color var(--duration-fast) var(--ease-spring);
}

.cv-btn:hover {
    background: var(--accent-hover);
}

.cv-btn:active,
.cv-btn.is-pressed {
    transform: scale(0.97);
}

.cv-btn.secondary {
    background: transparent;
    color: var(--accent);
    border: 1px solid var(--accent);
}

.cv-btn.secondary:hover {
    background: var(--accent);
    color: #fff;
}

.cv-embed-wrapper {
    width: 100%;
    max-width: 800px;
    margin: 0 auto;
    overflow: hidden;
}

.cv-iframe {
    width: 100%;
    min-height: 500px;
    border: none;
    display: block;
    background: transparent;
}

/* ==========================================================================
   Footer
   ========================================================================== */

.footer {
    padding: 2.5rem 0;
    text-align: center;
    border-top: 1px solid var(--border);
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 1rem;
}

.social-links a {
    color: var(--text-secondary);
    font-size: 1.35rem;
    transition: color var(--duration-fast) var(--ease-spring), transform var(--duration-fast) var(--ease-spring);
}

.social-links a:hover {
    color: var(--accent);
    transform: translateY(-3px);
}

.footer p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* ==========================================================================
   Hamburger — morphs into a close (X) glyph, hints at the outcome
   ========================================================================== */

.hamburger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    cursor: pointer;
    padding: 0.5rem;
    width: 34px;
    height: 34px;
}

.hamburger span {
    display: block;
    width: 22px;
    height: 2px;
    background-color: var(--text);
    border-radius: 2px;
    transition: transform var(--duration-base) var(--ease-spring), opacity var(--duration-fast) var(--ease-spring);
}

.hamburger.active span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

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

.hamburger.active span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ==========================================================================
   Scroll reveal
   ========================================================================== */

.fade-in {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.6s var(--ease-soft), transform 0.6s var(--ease-soft);
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
    .logo img {
        height: 26px;
    }

    .hamburger {
        display: flex;
    }

    .nav-links {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background-color: var(--nav-bg);
        backdrop-filter: blur(20px) saturate(180%);
        -webkit-backdrop-filter: blur(20px) saturate(180%);
        padding: 2rem;
        flex-direction: column;
        align-items: center;
        gap: 1.5rem;
        transform: translateY(-12px);
        opacity: 0;
        pointer-events: none;
        transition: transform var(--duration-base) var(--ease-spring), opacity var(--duration-base) var(--ease-spring);
        border-bottom: 1px solid var(--border);
    }

    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: auto;
    }

    .social-icons {
        margin-left: 0;
        padding-left: 0;
        border-left: none;
    }

    .about-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .profile-section {
        margin-bottom: 1rem;
    }

    .bio {
        max-width: none;
        margin: 0 auto;
    }

    .timeline::before {
        left: 1rem;
    }

    .timeline-content {
        width: calc(100% - 3rem);
        margin-left: 3rem !important;
    }

    .timeline-content::before {
        left: -2.45rem !important;
        right: auto !important;
    }

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

@media (max-width: 480px) {
    .container {
        padding: 0 1.25rem;
    }

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

    .contact-card {
        padding: 2.25rem 1.5rem;
    }
}

@media (max-width: 900px) {
    .project-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 600px) {
    .project-grid {
        grid-template-columns: 1fr;
    }

    .cv-iframe {
        min-height: 260px;
    }
}

/* ==========================================================================
   Accessibility & user preferences
   ========================================================================== */

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    * {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.2s !important;
    }

    .fade-in {
        transform: none;
    }

    .preview-card:hover,
    .project-card:hover,
    .education-item:hover,
    .btn:active,
    .contact-btn:active,
    .cv-btn:active,
    .github-repo-badge:active,
    .theme-toggle:active {
        transform: none;
    }
}

@media (prefers-reduced-transparency: reduce) {
    .navbar,
    .nav-links,
    .preview-card,
    .project-card,
    .timeline-content,
    .education-item,
    .contact-card,
    .cv-embed-wrapper {
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
        background-color: var(--surface-solid);
    }
}

/* ==========================================================================
   Teaser widget — a docked, self-animating icon that peeks a bubble
   ========================================================================== */

.teaser-widget {
    position: fixed;
    right: 1.5rem;
    bottom: 1.5rem;
    z-index: 1500;
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 0.75rem;
}

.teaser-fab {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-icon);
    border: none;
    background: var(--surface-solid);
    box-shadow: 0 10px 30px var(--shadow-color), inset 0 1px 0 rgba(255, 255, 255, 0.5);
    color: var(--text);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    animation: teaser-float 4s var(--ease-soft) infinite;
    transition: transform var(--duration-fast) var(--ease-spring), box-shadow var(--duration-base) var(--ease-spring);
}

.teaser-fab svg {
    width: 22px;
    height: 22px;
}

:root[data-theme="dark"] .teaser-fab {
    box-shadow: 0 10px 30px var(--shadow-color), inset 0 1px 0 rgba(255, 255, 255, 0.08);
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .teaser-fab {
        box-shadow: 0 10px 30px var(--shadow-color), inset 0 1px 0 rgba(255, 255, 255, 0.08);
    }
}

.teaser-fab:hover {
    box-shadow: 0 14px 36px var(--shadow-color), inset 0 1px 0 rgba(255, 255, 255, 0.5);
}

.teaser-fab:active,
.teaser-fab.is-pressed {
    transform: scale(0.92);
}

@keyframes teaser-float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.teaser-bubble {
    position: relative;
    padding: 0.65rem 1rem 0.65rem 0.65rem;
    border-radius: 1.1rem;
    background: var(--surface);
    backdrop-filter: blur(20px) saturate(160%);
    -webkit-backdrop-filter: blur(20px) saturate(160%);
    border: none;
    box-shadow: 0 1px 2px rgba(0, 0, 0, 0.04), 0 14px 34px var(--shadow-color);
    opacity: 0;
    transform: translateY(8px) scale(0.94);
    transform-origin: bottom right;
    pointer-events: none;
    transition: opacity var(--duration-base) var(--ease-spring), transform var(--duration-base) var(--ease-spring);
}

.teaser-item {
    display: none;
    align-items: center;
    gap: 0.6rem;
}

.teaser-item.is-active {
    display: flex;
}

.teaser-bubble::after {
    content: '';
    position: absolute;
    right: 20px;
    bottom: -6px;
    width: 12px;
    height: 12px;
    background: var(--surface-solid);
    box-shadow: 2px 2px 4px rgba(0, 0, 0, 0.04);
    transform: rotate(45deg);
}

.teaser-bubble.visible {
    opacity: 1;
    transform: translateY(0) scale(1);
    pointer-events: auto;
}

.teaser-app-icon {
    width: 38px;
    height: 38px;
    border-radius: var(--radius-icon);
    object-fit: cover;
    background: #1d1d1f;
    box-shadow: 0 6px 14px -2px color-mix(in srgb, var(--accent) 45%, transparent), inset 0 1px 0 rgba(255, 255, 255, 0.35);
    flex-shrink: 0;
}

.teaser-app-info {
    display: flex;
    flex-direction: column;
    line-height: 1.3;
    white-space: nowrap;
}

.teaser-app-name {
    font-size: 0.9rem;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: var(--text);
}

.teaser-app-badge {
    font-size: 0.75rem;
    font-weight: 500;
    letter-spacing: -0.005em;
    color: var(--accent);
}

@media (max-width: 480px) {
    .teaser-widget {
        right: 1rem;
        bottom: 1rem;
    }

    .teaser-fab {
        width: 50px;
        height: 50px;
        font-size: 1.15rem;
    }
}

@media (prefers-contrast: more) {
    .teaser-fab,
    .teaser-bubble {
        background: var(--surface-solid);
    }
}

@media (prefers-contrast: more) {
    :root {
        --border: var(--border-strong);
    }

    .preview-card,
    .project-card,
    .timeline-content,
    .education-item,
    .contact-card {
        border-width: 1.5px;
        background-color: var(--surface-solid);
    }
}