:root {
    /* Fonts */
    --font-primary: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-secondary: 'Roboto', sans-serif;

    /* Base Colors */
    --color-bg: #121212;
    --color-bg-container: #1e1e1e;
    --color-bg-header-footer: #1f2937;
    --color-text-primary: #e0e0e0;
    --color-text-secondary: #a0a0a0;
    --color-accent: #4f8ef7;
    --color-accent-hover: #82b1ff;
    --color-shadow: #00000099;

    /* Additional Palette */
    --color-success: #4caf50;
    --color-success-hover: #66bb6a;
    --color-warning: #fbc02d;
    --color-warning-hover: #ffca28;
    --color-error: #f44336;
    --color-error-hover: #ef5350;
    --color-info: #00bcd4;
    --color-info-hover: #26c6da;
    --color-border: #2c2c2c;
    --color-input-bg: #1a1a1a;
    --color-input-text: #e0e0e0;
    --color-input-placeholder: #888888;
    --color-button-text: #ffffff;

    /* Spacing */
    --space-xs: 5px;
    --space-sm: 10px;
    --space-md: 20px;
    --space-lg: 30px;
    --space-xl: 40px;

    /* Border radius */
    --radius-sm: 5px;
    --radius-md: 8px;
    --radius-lg: 12px;
}

/* Base resets */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: var(--font-primary);
    color: var(--color-text-primary);
    scrollbar-width: thin;
    scrollbar-color: var(--color-accent) var(--color-bg-container);
}

html,
body {
    height: 100%;
}

body {
    background-color: var(--color-bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    line-height: 1.6;
}

/* Scrollbars */
::-webkit-scrollbar {
    width: 12px;
    height: 12px;
}

::-webkit-scrollbar-track {
    background: var(--color-bg-container);
    border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb {
    background-color: var(--color-accent);
    border-radius: var(--radius-md);
    border: 3px solid var(--color-bg-container);
    transition: background-color 0.3s ease;
}

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

::-webkit-scrollbar-corner {
    background: var(--color-bg-container);
}

/* Headers & Footer */
header,
footer {
    background-color: var(--color-bg-header-footer);
    color: var(--color-text-primary);
    padding: var(--space-md);
    width: 100%;
}

header {
    border-radius: 0 0 var(--radius-md) var(--radius-md);
}

footer {
    border-radius: var(--radius-md) var(--radius-md) 0 0;
}

/* Navigation */
nav {
    margin-top: var(--space-lg);
}

nav a {
    color: var(--color-accent);
    text-decoration: none;
    margin: 0 var(--space-sm);
    font-size: 1.1rem;
    transition: color 0.3s ease;
}

nav a:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

/* Main content */
main {
    margin-top: var(--space-lg);
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 0 var(--space-md);
    flex: 1;
    padding-bottom: var(--space-xl);
}

.app-container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-lg);
    background-color: var(--color-bg-container);
    box-shadow: 0 0 15px var(--color-shadow);
    border-radius: var(--radius-md);
}

/* Typography */
h1 {
    font-family: var(--font-secondary);
    font-size: 2.5rem;
    margin-bottom: var(--space-sm);
    color: var(--color-text-primary);
}

h2 {
    font-family: var(--font-secondary);
    font-size: 2rem;
    margin-bottom: var(--space-sm);
    color: var(--color-accent);
}

p {
    font-size: 1.2rem;
    color: var(--color-text-secondary);
}

/* Links */
a {
    color: var(--color-accent);
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: var(--color-accent-hover);
    text-decoration: underline;
}

/* Sections */
section {
    margin: var(--space-lg);
}

.hero {
    text-align: center;
}

/* Lists */
ul {
    margin-top: var(--space-sm);
    padding-left: var(--space-lg);
}

li {
    margin-bottom: var(--space-xs);
    color: var(--color-text-secondary);
}

/* Buttons */
button {
    padding: var(--space-sm) var(--space-md);
    border: none;
    border-radius: var(--radius-sm);
    cursor: pointer;
    font-family: var(--font-secondary);
    font-weight: 500;
    transition: background-color 0.3s ease, transform 0.2s ease;
}

/* Button Variants */
button.primary {
    background-color: var(--color-accent);
    color: var(--color-button-text);
}

button.primary:hover {
    background-color: var(--color-accent-hover);
    transform: translateY(-1px);
}

button.success {
    background-color: var(--color-success);
    color: var(--color-button-text);
}

button.success:hover {
    background-color: var(--color-success-hover);
}

button.warning {
    background-color: var(--color-warning);
    color: var(--color-button-text);
}

button.warning:hover {
    background-color: var(--color-warning-hover);
}

button.error {
    background-color: var(--color-error);
    color: var(--color-button-text);
}

button.error:hover {
    background-color: var(--color-error-hover);
}

button.info {
    background-color: var(--color-info);
    color: var(--color-button-text);
}

button.info:hover {
    background-color: var(--color-info-hover);
}

/* Inputs & Textareas */
input,
textarea,
select {
    background-color: var(--color-input-bg);
    color: var(--color-input-text);
    border: 1px solid var(--color-border);
    padding: var(--space-sm);
    border-radius: var(--radius-sm);
    font-family: var(--font-primary);
    width: 100%;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

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

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--color-accent);
    box-shadow: 0 0 5px var(--color-accent);
}

/* Alerts */
.alert {
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--radius-sm);
    margin: var(--space-sm) 0;
    font-family: var(--font-primary);
}

.alert-success {
    background-color: var(--color-success);
    color: var(--color-button-text);
}

.alert-warning {
    background-color: var(--color-warning);
    color: var(--color-button-text);
}

.alert-error {
    background-color: var(--color-error);
    color: var(--color-button-text);
}

.alert-info {
    background-color: var(--color-info);
    color: var(--color-button-text);
}

/* Project Cards */
.project-card {
    background-color: var(--color-input-bg);
    padding: var(--space-md);
    border-radius: var(--radius-md);
    border: 1px solid var(--color-border);
    margin-top: var(--space-md);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 20px var(--color-shadow);
}

.project-card h3 {
    color: var(--color-accent);
    margin-bottom: var(--space-xs);
}

.project-tags {
    margin-top: var(--space-sm);
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-xs);
}

.tag {
    background-color: var(--color-bg-header-footer);
    color: var(--color-accent);
    padding: 4px 10px;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    border: 1px solid var(--color-border);
}

.project-links {
    margin-top: var(--space-sm);
    display: flex;
    gap: var(--space-md);
}

.project-links a {
    font-size: 0.95rem;
    font-weight: 500;
}

/* Contact Page */
.contact-links {
    margin-top: var(--space-md);
    display: flex;
    gap: var(--space-md);
    flex-wrap: wrap;
}

.contact-form {
    margin-top: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.contact-form .input {
    margin-bottom: var(--space-md);
    display: flex;
    flex-direction: column;
    gap: var(--space-xs);
}

.contact-form button {
    width: fit-content;
}

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

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

@keyframes pulse {
    0%,
    100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.03);
    }
}

/* Apply fade-in animation to containers */
.app-container,
header,
footer,
main {
    animation: fadeIn 0.5s ease forwards;
}

/* Headings gently fade in upwards */
h1, h2, p {
    animation: fadeUp 0.6s ease forwards;
}

/* Links */
a {
    transition: color 0.3s ease, transform 0.2s ease;
}

a:hover {
    transform: translateY(-2px);
}

/* Buttons */
button {
    transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.2s ease;
}

button:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--color-shadow);
}

/* Alerts: subtle fade and pulse on mount */
.alert {
    animation: fadeIn 0.4s ease forwards;
}

.alert-success,
.alert-warning,
.alert-error,
.alert-info {
    transition: background-color 0.3s ease, transform 0.2s ease;
}

.alert-success:hover,
.alert-warning:hover,
.alert-error:hover,
.alert-info:hover {
    animation: pulse 1s ease infinite;
}

/* Inputs & Textareas */
input, textarea, select {
    transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.2s ease;
}

input:focus,
textarea:focus,
select:focus {
    transform: scale(1.01);
}

/* Nav Links: subtle hover movement */
nav a:hover {
    transform: translateY(-2px);
}

/* Optional: staggered fade-in for children inside app-container */
.app-container > * {
    opacity: 0;
    animation: fadeUp 0.5s ease forwards;
}

.app-container > *:nth-child(1) { animation-delay: 0.1s; }
.app-container > *:nth-child(2) { animation-delay: 0.2s; }
.app-container > *:nth-child(3) { animation-delay: 0.3s; }
.app-container > *:nth-child(4) { animation-delay: 0.4s; }