/* ============================================
   Base Styles
   Reset, Typography, and Foundation
   ============================================ */

/* ========== Modern CSS Reset ========== */
*{user-select: none;}
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
}

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    font-weight: var(--font-normal);
    line-height: var(--leading-normal);
    color: var(--color-text-primary);
    background-color: var(--color-bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

/* ========== Typography ========== */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-primary);
    font-weight: var(--font-bold);
    line-height: var(--leading-tight);
    letter-spacing: var(--tracking-tight);
    color: var(--color-text-primary);
}

h1 {
    font-size: var(--text-5xl);
}

h2 {
    font-size: var(--text-4xl);
}

h3 {
    font-size: var(--text-2xl);
}

h4 {
    font-size: var(--text-xl);
}

h5 {
    font-size: var(--text-lg);
}

h6 {
    font-size: var(--text-base);
}

p {
    font-size: var(--text-base);
    line-height: var(--leading-relaxed);
    color: var(--color-text-secondary);
}

p+p {
    margin-top: var(--space-4);
}

strong,
b {
    font-weight: var(--font-semibold);
    color: var(--color-text-primary);
}

em,
i {
    font-style: italic;
}

small {
    font-size: var(--text-sm);
}

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

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

a:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* ========== Lists ========== */
ul,
ol {
    list-style: none;
}

/* ========== Images ========== */
img,
picture,
video,
canvas,
svg {
    display: block;
    max-width: 100%;
    height: auto;
}

/* ========== Form Elements ========== */
button,
input,
select,
textarea {
    font: inherit;
    color: inherit;
}

button {
    cursor: pointer;
    background: none;
    border: none;
}

input,
textarea {
    background-color: var(--color-bg-tertiary);
    border: var(--border-thin);
    padding: var(--space-3) var(--space-4);
    border-radius: var(--radius-sm);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

input:focus,
textarea:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: var(--shadow-glow);
}

/* ========== Code ========== */
code,
kbd,
samp,
pre {
    font-family: var(--font-mono);
    font-size: var(--text-sm);
}

code {
    background-color: var(--color-bg-tertiary);
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
    color: var(--color-primary-light);
}

pre {
    background-color: var(--color-bg-tertiary);
    padding: var(--space-4);
    border-radius: var(--radius-md);
    overflow-x: auto;
    border: var(--border-thin);
}

pre code {
    background: none;
    padding: 0;
}

/* ========== Selection ========== */
::selection {
    background-color: var(--color-primary);
    color: var(--color-text-inverse);
}

/* ========== Focus Styles ========== */
:focus {
    outline: none;
}

:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* ========== Scrollbar ========== */
::-webkit-scrollbar {
    width: 10px;
    height: 10px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-secondary);
}

::-webkit-scrollbar-thumb {
    background: var(--color-border-strong);
    border-radius: var(--radius-lg);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-primary);
}

/* Firefox */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--color-border-strong) var(--color-bg-secondary);
}

/* ========== 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-width: 0;
}

.container {
    width: 100%;
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

/* ========== Scroll Progress Bar ========== */
.scroll-progress {
    position: fixed;
    top: 0;
    left: 0;
    width: 0%;
    height: 3px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-primary-light));
    z-index: var(--z-fixed);
    transition: width 50ms ease-out;
}