/*
 * Kaan Esendemir - Personal Website
 * Terminal-Inspired Light Theme
 */

/* ========================================
   CSS Custom Properties
   ======================================== */
:root {
    /* Light Theme Colors */
    --color-bg: #fafafa;
    --color-bg-alt: #f0f0f0;
    --color-bg-card: #ffffff;
    --color-border: #e0e0e0;
    --color-border-light: #ebebeb;

    /* Text Colors */
    --color-text: #374151;
    --color-text-secondary: #6b7280;
    --color-text-muted: #9ca3af;
    --color-text-dark: #111827;

    /* Accent Colors - Slate Blue */
    --color-primary: #4A6FA5;
    --color-primary-hover: #3B5A8A;
    --color-primary-dim: rgba(74, 111, 165, 0.1);

    /* Secondary accent - deeper blue */
    --color-secondary: #3B5A8A;
    --color-secondary-hover: #2E4870;
    --color-secondary-dim: rgba(59, 90, 138, 0.08);

    /* Typography */
    --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', 'Consolas', monospace;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 0.75rem;
    --space-lg: 1rem;
    --space-xl: 1.5rem;
    --space-2xl: 2rem;
    --space-3xl: 3rem;
    --space-4xl: 4rem;

    /* Layout */
    --container-max: 1100px;
    --sidebar-width: 180px;
    --content-max: 720px;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

/* ========================================
   Reset & Base
   ======================================== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 15px;
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font-mono);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.6;
    min-height: 100vh;
}

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

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

a:hover {
    color: var(--color-primary-hover);
}

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

/* ========================================
   Typography
   ======================================== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-text-dark);
}

h1 {
    font-size: 1.75rem;
    font-weight: 700;
}

h2 {
    font-size: 1.125rem;
    margin-bottom: var(--space-md);
}

h3 {
    font-size: 0.9375rem;
    margin-bottom: var(--space-sm);
}

p {
    margin-bottom: var(--space-md);
}

.lead {
    font-size: 0.875rem;
    color: var(--color-text-secondary);
    line-height: 1.7;
}

/* ========================================
   Main Layout
   ======================================== */
.page-wrapper {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-2xl) var(--space-lg);
    display: grid;
    grid-template-columns: 1fr var(--sidebar-width);
    gap: var(--space-3xl);
    position: relative;
}

.main-content {
    max-width: var(--content-max);
}

/* ========================================
   Mobile Menu Toggle
   ======================================== */
.menu-toggle {
    display: none;
    position: fixed;
    top: var(--space-lg);
    right: var(--space-lg);
    z-index: 1000;
    width: 40px;
    height: 40px;
    padding: 0;
    border: 1px solid var(--color-border);
    border-radius: 6px;
    background: var(--color-bg-card);
    cursor: pointer;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 4px;
    box-shadow: var(--shadow-md);
}

.menu-toggle__bar {
    display: block;
    width: 18px;
    height: 2px;
    background: var(--color-text);
    border-radius: 1px;
    transition: all var(--transition-fast);
}

.menu-toggle.is-active .menu-toggle__bar:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
}

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

.menu-toggle.is-active .menu-toggle__bar:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
}

/* ========================================
   Sidebar Navigation
   ======================================== */
.sidebar {
    position: sticky;
    top: var(--space-2xl);
    height: fit-content;
    padding-left: var(--space-xl);
    border-left: 1px solid var(--color-border);
}

.sidebar__nav {
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.sidebar__link {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    padding: var(--space-xs) var(--space-sm);
    border-radius: 3px;
    transition: all var(--transition-fast);
    position: relative;
}

.sidebar__link:hover {
    color: var(--color-text-dark);
    background: var(--color-bg-alt);
}

.sidebar__link:hover::before {
    content: "> ";
    color: var(--color-primary);
    position: absolute;
    left: -0.75rem;
}

.sidebar__link--active {
    color: var(--color-text-dark);
    background: var(--color-bg-alt);
}

.sidebar__link--active::before {
    content: "> ";
    color: var(--color-primary);
    position: absolute;
    left: -0.75rem;
}

/* ========================================
   Profile Header
   ======================================== */
.profile {
    display: flex;
    gap: var(--space-xl);
    align-items: flex-start;
    margin-bottom: var(--space-3xl);
    padding-bottom: var(--space-2xl);
    border-bottom: 1px solid var(--color-border);
}

.profile__photo {
    width: 120px;
    height: 120px;
    border-radius: 6px;
    overflow: hidden;
    flex-shrink: 0;
    background: var(--color-bg-alt);
    border: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.profile__photo svg {
    width: 48px;
    height: 48px;
    color: var(--color-text-muted);
}

.profile__info {
    flex: 1;
}

.profile__name {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-text-dark);
    margin-bottom: var(--space-xs);
}

.profile__name::before {
    content: "$ ";
    color: var(--color-primary);
}

.profile__title {
    font-size: 0.875rem;
    color: var(--color-primary);
    margin-bottom: var(--space-md);
}

.profile__bio {
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-lg);
}

.profile__links {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
}

/* ========================================
   Sections
   ======================================== */
.section {
    margin-bottom: var(--space-3xl);
    scroll-margin-top: var(--space-2xl);
}

.section:last-child {
    margin-bottom: 0;
}

.section__title {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--color-text-dark);
    margin-bottom: var(--space-lg);
    padding-bottom: var(--space-sm);
    border-bottom: 1px solid var(--color-border);
    text-transform: lowercase;
}

.section__title::before {
    content: "## ";
    color: var(--color-primary);
}

/* ========================================
   Cards & Items
   ======================================== */
.card {
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    padding: var(--space-lg);
    margin-bottom: var(--space-md);
    box-shadow: var(--shadow-sm);
}

.card:last-child {
    margin-bottom: 0;
}

.card__label {
    display: inline-block;
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--color-primary);
    background: var(--color-primary-dim);
    padding: 0.125rem 0.5rem;
    border-radius: 3px;
    margin-bottom: var(--space-sm);
}

.card__title {
    font-size: 0.875rem;
    font-weight: 600;
    margin-bottom: var(--space-sm);
    color: var(--color-text-dark);
    line-height: 1.4;
}

.card__meta {
    font-size: 0.6875rem;
    color: var(--color-text-muted);
    margin-bottom: var(--space-sm);
}

.card__text {
    font-size: 0.8125rem;
    color: var(--color-text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-sm);
}

.card__text:last-child {
    margin-bottom: 0;
}

/* ========================================
   About Text
   ======================================== */
.about-text {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.about-text p {
    font-size: 0.875rem;
    line-height: 1.75;
    color: var(--color-text-secondary);
    margin: 0;
}

.about-text__heading {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-text-dark);
    margin: 0 0 var(--space-sm) 0;
    padding-top: var(--space-md);
}

.about-text__heading:first-child {
    padding-top: 0;
}

/* ========================================
   Tags
   ======================================== */
.tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
    margin-top: var(--space-sm);
}

.tag {
    display: inline-block;
    font-size: 0.625rem;
    font-weight: 500;
    padding: 0.125rem 0.375rem;
    background-color: var(--color-primary-dim);
    color: var(--color-primary);
    border-radius: 3px;
    border: 1px solid transparent;
}

/* ========================================
   Experience Lines
   ======================================== */
.experience-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.experience-line {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) 0;
    font-size: 0.8125rem;
    border-bottom: 1px solid var(--color-border-light);
}

.experience-line:last-child {
    border-bottom: none;
}

.experience-line__org {
    font-weight: 600;
    color: var(--color-text-dark);
}

.experience-line__role {
    color: var(--color-text-secondary);
}

.experience-line__years {
    margin-left: auto;
    font-size: 0.6875rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    padding: 0.125rem 0.5rem;
    background-color: var(--color-primary-dim);
    color: var(--color-primary);
    border-radius: 3px;
    white-space: nowrap;
}

@media (max-width: 600px) {
    .experience-line {
        flex-wrap: wrap;
    }

    .experience-line__years {
        margin-left: 0;
        margin-top: var(--space-xs);
    }
}

/* ========================================
   Education Lines
   ======================================== */
.education-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.education-line {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: var(--space-sm) 0;
    font-size: 0.8125rem;
    border-bottom: 1px solid var(--color-border-light);
}

.education-line:last-child {
    border-bottom: none;
}

.education-line__school {
    font-weight: 600;
    color: var(--color-text-dark);
}

.education-line__degree {
    color: var(--color-text-secondary);
}

/* ========================================
   Item Lists
   ======================================== */
.item-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

.item-list--horizontal {
    flex-direction: row;
}

.item-list--horizontal .item {
    flex: 1;
}

.item {
    display: flex;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    box-shadow: var(--shadow-sm);
}

.item__icon {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-primary-dim);
    border-radius: 4px;
    color: var(--color-primary);
    flex-shrink: 0;
}

.item__icon svg {
    width: 16px;
    height: 16px;
}

.item__content {
    flex: 1;
    min-width: 0;
}

.item__title {
    font-size: 0.8125rem;
    font-weight: 600;
    color: var(--color-text-dark);
    margin-bottom: var(--space-xs);
}

.item__subtitle {
    font-size: 0.6875rem;
    color: var(--color-text-secondary);
}

.item__desc {
    font-size: 0.75rem;
    color: var(--color-text-muted);
    margin-top: var(--space-xs);
    line-height: 1.5;
}

/* ========================================
   Profile Links
   ======================================== */
.profile-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    font-size: 0.6875rem;
    font-weight: 500;
    color: var(--color-text-secondary);
    padding: 0.25rem 0.625rem;
    border: 1px solid var(--color-border);
    border-radius: 4px;
    transition: all var(--transition-fast);
    background: var(--color-bg-card);
}

.profile-link:hover {
    color: var(--color-primary);
    border-color: var(--color-primary);
    background-color: var(--color-primary-dim);
}

.profile-link svg {
    width: 12px;
    height: 12px;
}

.profile-link--disabled {
    opacity: 0.5;
    cursor: default;
}

.profile-link--disabled:hover {
    color: var(--color-text-secondary);
    border-color: var(--color-border);
    background-color: var(--color-bg-card);
}

.profile-link--icon {
    padding: 0.375rem;
    gap: 0;
}

.profile-link--icon svg {
    width: 14px;
    height: 14px;
}

/* ========================================
   Buttons
   ======================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    padding: 0.375rem 0.75rem;
    font-family: var(--font-mono);
    font-size: 0.75rem;
    font-weight: 500;
    border-radius: 4px;
    border: 1px solid transparent;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
}

.btn--primary {
    background-color: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
}

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

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

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

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

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

/* ========================================
   Topics Grid
   ======================================== */
.topics-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-sm);
}

.topic-item {
    font-size: 0.75rem;
    color: var(--color-text-secondary);
    padding: var(--space-sm) var(--space-md);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 4px;
}

.topic-item::before {
    content: "- ";
    color: var(--color-primary);
}

/* ========================================
   Empty State
   ======================================== */
.empty-state {
    padding: var(--space-xl);
    background: var(--color-bg-alt);
    border-radius: 6px;
    border: 1px dashed var(--color-border);
    text-align: center;
}

.empty-state__text {
    font-size: 0.75rem;
    color: var(--color-text-muted);
}

.empty-state__text::before {
    content: "// ";
    color: var(--color-text-muted);
}

/* ========================================
   Contact Section
   ======================================== */
.contact-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}

.contact-item {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    padding: var(--space-md);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border);
    border-radius: 6px;
    box-shadow: var(--shadow-sm);
}

.contact-item__icon {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-primary-dim);
    border-radius: 4px;
    color: var(--color-primary);
}

.contact-item__icon svg {
    width: 14px;
    height: 14px;
}

.contact-item__label {
    font-size: 0.625rem;
    color: var(--color-text-muted);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.contact-item__value {
    font-size: 0.75rem;
    font-weight: 500;
    color: var(--color-text-dark);
}

.contact-item__value a {
    color: var(--color-primary);
}

.contact-item__value a:hover {
    color: var(--color-primary-hover);
}

/* Contact Row Layout */
.contact-row {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-lg);
}

.contact-row .contact-grid {
    flex: 1;
}

.contact-row .btn {
    flex-shrink: 0;
    align-self: center;
}

/* ========================================
   Footer
   ======================================== */
.footer {
    padding: var(--space-xl) var(--space-lg);
    border-top: 1px solid var(--color-border);
    margin-top: var(--space-2xl);
    background: var(--color-bg-alt);
}

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

.footer__copy {
    font-size: 0.625rem;
    color: var(--color-text-muted);
}

.footer__links {
    display: flex;
    gap: var(--space-lg);
}

.footer__link {
    font-size: 0.625rem;
    color: var(--color-text-muted);
}

.footer__link:hover {
    color: var(--color-primary);
}

/* ========================================
   Responsive
   ======================================== */
@media (max-width: 900px) {
    .menu-toggle {
        display: flex;
    }

    .page-wrapper {
        grid-template-columns: 1fr;
        gap: var(--space-xl);
        padding-top: var(--space-4xl);
    }

    .sidebar {
        position: fixed;
        top: 0;
        right: -100%;
        width: 200px;
        height: 100vh;
        background: var(--color-bg-card);
        border-left: 1px solid var(--color-border);
        padding: var(--space-4xl) var(--space-xl) var(--space-xl);
        z-index: 999;
        transition: right var(--transition-base);
        box-shadow: -4px 0 20px rgba(0, 0, 0, 0.1);
    }

    .sidebar.is-open {
        right: 0;
    }

    .sidebar__nav {
        flex-direction: column;
        gap: var(--space-xs);
    }

    .sidebar__link {
        font-size: 0.875rem;
        padding: var(--space-sm) var(--space-md);
    }

    .sidebar__link::before {
        display: none;
    }

    .sidebar__link:hover::before,
    .sidebar__link--active::before {
        display: block;
        left: 0;
    }

    .main-content {
        max-width: 100%;
    }

    .profile {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .profile__links {
        justify-content: center;
    }

    .contact-row {
        flex-direction: column;
        align-items: stretch;
    }

    .contact-row .btn {
        align-self: flex-start;
        margin-top: var(--space-lg);
    }

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

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

    /* Overlay for mobile menu */
    .menu-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.3);
        z-index: 998;
    }

    .menu-overlay.is-visible {
        display: block;
    }
}

@media (max-width: 600px) {
    html {
        font-size: 14px;
    }

    .page-wrapper {
        padding: var(--space-lg);
    }

    .profile__photo {
        width: 100px;
        height: 100px;
    }

    .profile__name {
        font-size: 1.25rem;
    }

    .footer__inner {
        flex-direction: column;
        text-align: center;
    }

    .item-list--horizontal {
        flex-direction: column;
    }
}

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

.mt-sm { margin-top: var(--space-sm); }
.mt-md { margin-top: var(--space-md); }
.mt-lg { margin-top: var(--space-lg); }
.mt-xl { margin-top: var(--space-xl); }

.mb-sm { margin-bottom: var(--space-sm); }
.mb-md { margin-bottom: var(--space-md); }
.mb-lg { margin-bottom: var(--space-lg); }
.mb-xl { margin-bottom: var(--space-xl); }