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

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -webkit-tap-highlight-color: transparent;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    font-weight: var(--font-normal);
    line-height: var(--leading-normal);
    color: var(--color-text);
    background: var(--color-bg);
    min-height: 100vh;
    min-height: 100dvh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

h1 { font-size: var(--text-4xl); }
h2 { font-size: var(--text-3xl); }
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 {
    color: var(--color-text-secondary);
}

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

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

/* Forms */
input, textarea, select, button {
    font-family: inherit;
    font-size: inherit;
    line-height: inherit;
    color: inherit;
}

input, textarea, select {
    width: 100%;
    padding: var(--space-3) var(--space-4);
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text);
    transition: all var(--transition-fast);
}

input:focus, textarea:focus, select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-muted);
}

input::placeholder, textarea::placeholder {
    color: var(--color-text-muted);
}

input:disabled, textarea:disabled, select:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

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

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

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
}

/* Buttons */
button {
    cursor: pointer;
    border: none;
    background: transparent;
}

button:disabled {
    cursor: not-allowed;
    opacity: 0.5;
}

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

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

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--color-border-hover);
    border-radius: var(--radius-full);
}

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

/* Utility Classes */
.hidden {
    display: none !important;
}

.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;
}

/* Loading Animation */
@keyframes spin {
    to { transform: rotate(360deg); }
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { 
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateX(-20px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

/* Loader Circle Animation */
@keyframes loaderRotate {
    100% { transform: rotate(360deg); }
}

.loader-circle {
    animation: loaderRotate 1.5s linear infinite;
    transform-origin: center;
}