/* Reset & Base Styles */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
}

html {
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-sans);
    background: var(--bg);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    line-height: 1.5;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.2;
    color: var(--text-primary);
}

h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }
h5 { font-size: 1rem; }
h6 { font-size: 0.875rem; }

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

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

a:hover {
    color: var(--accent-dark);
}

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

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

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

input:focus, textarea:focus, select:focus {
    outline: none;
}

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

/* Scrollbar */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--border-dark);
    border-radius: 3px;
}

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

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

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

/* App Container */
.app-container {
    max-width: 100%;
    margin: 0 auto;
    background: var(--bg);
    min-height: 100vh;
    position: relative;
}

/* Mobile (default) */
@media (max-width: 767px) {
    .app-container {
        max-width: 100%;
        padding-bottom: 90px;
    }
}

/* Tablet/iPad */
@media (min-width: 768px) and (max-width: 1024px) {
    .app-container {
        max-width: 600px;
        padding-bottom: 100px;
    }
}

/* Desktop/Web */
@media (min-width: 1025px) {
    .app-container {
        max-width: 1200px;
        display: grid;
        grid-template-columns: var(--sidebar-width) 1fr;
        gap: 24px;
        padding: 24px;
    }
}

/* Page Transitions */
.page {
    display: none;
    animation: fadeIn 0.3s ease;
}

.page.active {
    display: block;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

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

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

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

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* 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;
}

.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-accent { color: var(--accent); }
.text-success { color: var(--success); }
.text-warning { color: var(--warning); }
.text-danger { color: var(--danger); }

.bg-card { background: var(--card-bg); }
.bg-secondary { background: var(--bg-secondary); }

.animate-slide-up {
    animation: slideUp 0.5s ease forwards;
}

.animate-scale-in {
    animation: scaleIn 0.3s ease forwards;
}

.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

/* Responsive Typography */
@media (min-width: 768px) {
    html {
        font-size: 17px;
    }
}

@media (min-width: 1025px) {
    html {
        font-size: 18px;
    }
}