/* =====================================================================
   VARIABLES
   ===================================================================== */

:root {
    --color-bg: #ffffff;
    --color-bg-alt: #f8fafc;
    --color-bg-card: #ffffff;

    --color-text: #0f172a;
    --color-text-muted: #64748b;

    --color-accent: #2563eb;
    --color-accent-dark: #1d4ed8;
    --color-accent-light: #eff6ff;

    --color-border: #e2e8f0;

    --radius-sm: 6px;
    --radius: 12px;
    --radius-lg: 16px;

    --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
    --shadow: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.1);

    --content-width: 1100px;
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, sans-serif;

    --header-h: 64px;
}

.theme-dark {
    --color-bg: #0f172a;
    --color-bg-alt: #1e293b;
    --color-bg-card: #1e293b;

    --color-text: #f1f5f9;
    --color-text-muted: #94a3b8;

    --color-accent: #3b82f6;
    --color-accent-dark: #2563eb;
    --color-accent-light: rgba(59,130,246,0.12);

    --color-border: #334155;

    --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
    --shadow: 0 4px 16px rgba(0,0,0,0.4);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.5);
}


/* =====================================================================
   RESET & BASE
   ===================================================================== */

*, *::before, *::after { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    margin: 0;
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    background: var(--color-bg);
    color: var(--color-text);
    transition: background 0.3s, color 0.3s;
    -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; }
a { color: inherit; }
button { font-family: inherit; }

.skip-link {
    position: absolute;
    top: -40px;
    left: 12px;
    padding: 6px 12px;
    background: var(--color-accent);
    color: #fff;
    border-radius: var(--radius-sm);
    font-size: 0.875rem;
    text-decoration: none;
    z-index: 9999;
}
.skip-link:focus { top: 12px; }


/* =====================================================================
   LAYOUT HELPERS
   ===================================================================== */

.container {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.section {
    padding: 6rem 0;
}

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

.section-header {
    margin-bottom: 3rem;
}

.section-label {
    display: inline-block;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: 0.5rem;
}

.section-title {
    font-size: clamp(1.75rem, 4vw, 2.25rem);
    font-weight: 700;
    margin: 0 0 0.75rem;
    letter-spacing: -0.02em;
    color: var(--color-text);
}

.section-subtitle {
    color: var(--color-text-muted);
    margin: 0;
    font-size: 1.05rem;
    max-width: 520px;
}


/* =====================================================================
   BUTTONS
   ===================================================================== */

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.4em;
    padding: 0.65rem 1.4rem;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    border: 2px solid transparent;
    transition: background 0.2s, color 0.2s, border-color 0.2s, transform 0.15s, box-shadow 0.2s;
    white-space: nowrap;
}

.btn--primary {
    background: var(--color-accent);
    color: #fff;
    border-color: var(--color-accent);
}
.btn--primary:hover {
    background: var(--color-accent-dark);
    border-color: var(--color-accent-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37,99,235,0.3);
}

.btn--outline {
    background: transparent;
    color: var(--color-accent);
    border-color: var(--color-accent);
}
.btn--outline:hover {
    background: var(--color-accent-light);
    transform: translateY(-1px);
}

.btn--sm {
    padding: 0.45rem 1rem;
    font-size: 0.82rem;
}


/* =====================================================================
   HEADER
   ===================================================================== */

.header {
    position: sticky;
    top: 0;
    height: var(--header-h);
    background: rgba(255,255,255,0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
    z-index: 100;
    transition: background 0.3s, border-color 0.3s;
}

.theme-dark .header {
    background: rgba(15,23,42,0.85);
}

.header__inner {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header__logo {
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--color-accent);
    text-decoration: none;
    letter-spacing: -0.01em;
}

/* Hamburger */
.header__menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.header__menu-toggle span {
    display: block;
    width: 22px;
    height: 2px;
    background: var(--color-text);
    border-radius: 2px;
    transition: transform 0.25s, opacity 0.25s;
}

@media (max-width: 767px) {
    .header__menu-toggle { display: flex; }
    .header__nav {
        display: none;
        position: absolute;
        top: var(--header-h);
        left: 0;
        right: 0;
        background: var(--color-bg);
        border-bottom: 1px solid var(--color-border);
        padding: 1rem 1.5rem 1.5rem;
    }
    .header__nav--open { display: block; }
    .header__nav-list {
        flex-direction: column;
        gap: 0.25rem;
    }
}

.header__nav-list {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    align-items: center;
    gap: 0.25rem;
}

.header__nav-link {
    display: block;
    padding: 0.4rem 0.75rem;
    border-radius: var(--radius-sm);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--color-text-muted);
    transition: color 0.2s, background 0.2s;
}
.header__nav-link:hover {
    color: var(--color-text);
    background: var(--color-bg-alt);
}
.header__nav-link.active {
    color: var(--color-accent);
}


/* =====================================================================
   THEME TOGGLE
   ===================================================================== */

.theme-toggle {
    background: none;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--color-text-muted);
    transition: background 0.2s, color 0.2s;
}
.theme-toggle:hover {
    background: var(--color-bg-alt);
    color: var(--color-text);
}
.theme-toggle svg {
    width: 16px;
    height: 16px;
}
.theme-toggle .icon-sun { display: none; }
.theme-dark .theme-toggle .icon-sun { display: block; }
.theme-dark .theme-toggle .icon-moon { display: none; }


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

.hero {
    padding: 5rem 0 4rem;
    min-height: calc(100vh - var(--header-h));
    display: flex;
    align-items: center;
}

.hero__inner {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 4rem;
    align-items: center;
}

.hero__eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.82rem;
    font-weight: 600;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin-bottom: 1rem;
}
.hero__eyebrow::before {
    content: '';
    display: inline-block;
    width: 24px;
    height: 2px;
    background: var(--color-accent);
    border-radius: 2px;
}

.hero__title {
    font-size: clamp(2.2rem, 5vw, 3.25rem);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.15;
    margin: 0 0 1.25rem;
    color: var(--color-text);
}

.hero__name {
    color: var(--color-accent);
}

.hero__subtitle {
    font-size: 1.05rem;
    color: var(--color-text-muted);
    max-width: 480px;
    margin: 0 0 2rem;
    line-height: 1.7;
}

.hero__actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
}

.hero__image-frame {
    width: 280px;
    height: 320px;
    border-radius: var(--radius-lg);
    overflow: hidden;
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
}
.hero__image-frame img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: opacity 0.3s;
}

@media (max-width: 768px) {
    .hero__inner {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 2.5rem;
    }
    .hero__eyebrow { justify-content: center; }
    .hero__subtitle { margin: 0 auto 2rem; }
    .hero__actions { justify-content: center; }
    .hero__image { display: flex; justify-content: center; }
    .hero__image-frame { width: 220px; height: 250px; }
}


/* =====================================================================
   ABOUT
   ===================================================================== */

.about__grid {
    display: grid;
    grid-template-columns: 1fr auto;
    gap: 4rem;
    align-items: start;
}

.about__text p {
    color: var(--color-text-muted);
    margin: 0 0 1.1rem;
    font-size: 1.02rem;
    line-height: 1.75;
    max-width: 560px;
}

.about__links {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.about__social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.88rem;
    font-weight: 600;
    color: var(--color-text-muted);
    text-decoration: none;
    padding: 0.45rem 0.9rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.about__social-link svg { width: 16px; height: 16px; }
.about__social-link:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
    background: var(--color-accent-light);
}

.about__stats {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    min-width: 160px;
}

.stat-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 1.25rem 1.5rem;
    box-shadow: var(--shadow-sm);
    text-align: center;
}
.stat-card__number {
    display: block;
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: -0.02em;
    line-height: 1;
    margin-bottom: 0.3rem;
}
.stat-card__label {
    font-size: 0.8rem;
    color: var(--color-text-muted);
    font-weight: 500;
}

@media (max-width: 768px) {
    .about__grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    .about__stats {
        flex-direction: row;
        flex-wrap: wrap;
        min-width: unset;
    }
    .stat-card { flex: 1; min-width: 120px; }
}


/* =====================================================================
   SKILLS
   ===================================================================== */

.skills__grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

@media (max-width: 700px) {
    .skills__grid { grid-template-columns: 1fr; }
}

.skill-group {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    padding: 1.5rem;
    box-shadow: var(--shadow-sm);
}

.skill-group__title {
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--color-accent);
    margin: 0 0 1rem;
}

.skill-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.skill-tag {
    font-size: 0.8rem;
    font-weight: 500;
    color: var(--color-text-muted);
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    padding: 0.3rem 0.7rem;
    border-radius: 100px;
    transition: color 0.2s, border-color 0.2s;
}
.skill-tag:hover {
    color: var(--color-accent);
    border-color: var(--color-accent);
}


/* =====================================================================
   PROJECTS
   ===================================================================== */

.projects__grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

@media (max-width: 900px) {
    .projects__grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 600px) {
    .projects__grid { grid-template-columns: 1fr; }
}

.project-card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    transition: transform 0.2s, box-shadow 0.2s;
}
.project-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.project-card__image {
    height: 160px;
    overflow: hidden;
}
.project-card__image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.project-card__image--placeholder {
    background: var(--color-accent-light);
    display: flex;
    align-items: center;
    justify-content: center;
}
.project-card__image--placeholder span {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-accent);
    letter-spacing: -0.02em;
    opacity: 0.6;
}

.project-card__body {
    padding: 1.25rem;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.project-card__title {
    font-size: 1.05rem;
    font-weight: 700;
    margin: 0 0 0.5rem;
    color: var(--color-text);
}

.project-card__description {
    font-size: 0.88rem;
    color: var(--color-text-muted);
    line-height: 1.6;
    margin: 0 0 1rem;
    flex: 1;
}

.project-card__tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    margin-bottom: 1.1rem;
}
.project-card__tags span {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-accent);
    background: var(--color-accent-light);
    padding: 0.25rem 0.6rem;
    border-radius: 100px;
}

.project-card__actions {
    margin-top: auto;
}


/* =====================================================================
   CONTACT
   ===================================================================== */

.contact__wrapper {
    max-width: 560px;
}

.contact__form {
    display: flex;
    flex-direction: column;
    gap: 1.1rem;
    margin-bottom: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.form-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--color-text);
}

.form-input {
    width: 100%;
    padding: 0.65rem 0.9rem;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    color: var(--color-text);
    transition: border-color 0.2s, box-shadow 0.2s;
}
.form-input::placeholder { color: var(--color-text-muted); }
.form-input:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 0 3px rgba(37,99,235,0.1);
}

.form-textarea {
    resize: vertical;
    min-height: 130px;
}

.contact__info {
    margin-top: 1.25rem;
}
.contact__info-text {
    font-size: 0.88rem;
    color: var(--color-text-muted);
    margin: 0 0 0.3rem;
}
.contact__email {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--color-accent);
    text-decoration: none;
}
.contact__email:hover { text-decoration: underline; }


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

.footer {
    border-top: 1px solid var(--color-border);
    padding: 1.75rem 0;
    background: var(--color-bg);
}

.footer__inner {
    max-width: var(--content-width);
    margin: 0 auto;
    padding: 0 1.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
    flex-wrap: wrap;
}

.footer__text {
    font-size: 0.85rem;
    color: var(--color-text-muted);
    margin: 0;
}

.footer__nav {
    display: flex;
    gap: 1.25rem;
    flex-wrap: wrap;
}

.footer__link {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--color-text-muted);
    text-decoration: none;
    transition: color 0.2s;
}
.footer__link:hover { color: var(--color-accent); }


/* =====================================================================
   SCROLL ANIMATIONS
   ===================================================================== */

.reveal {
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}
.reveal.visible {
    opacity: 1;
    transform: none;
}

@media (prefers-reduced-motion: reduce) {
    .reveal { opacity: 1; transform: none; }
}