/* Universal Styles */

* {
    box-sizing: border-box;
}

:root {
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-dark: #0f172a;
  --accent-color: #38bdf8;
  --border-card-color: rgba(255, 255, 255, 0.12);
  --surface-card: rgba(255, 255, 255, 0.03);
  --surface-section: rgba(255, 255, 255, 0.02);
  --color-palette1: #072260;
  --color-palette2: #DC143C;
  --color-palette3: #C5D86D;
  --color-palette4: #AFE0CE;
  --color-palette5: #FFEDDF;
  --color-palette6: #86615C;
  --color-palette7: #FF00FF;
  --color-palette8: #FF4500;
  --color-palette9: #FFFF00;
  --color-palette10: #7FFFD4;
  --color-palette11: #00FF7F;
  --color-palette12: #fa8072;
}

html {
    font-family: "Georgia", serif;
    font-size: 16px;
    scroll-behavior: smooth;
}

body {
    background: linear-gradient(135deg, #0f172a, #1e293b);
    color: var(--text-primary);
    margin: 0;
    line-height: 1.5;
}

.main-content {
    padding: 0 1rem 2rem;
}

/* Header */

header {
  width: 100%;
  border-bottom: solid 1px var(--border-card-color);
}

header .content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 1.5rem;
    min-height: 3.5rem;
    padding: 1rem;
    flex-wrap: wrap;
}

header .main-title {
    flex: 1 1 260px;
    margin: 0;
    font-size: clamp(1.5rem, 2vw, 2rem);
}

header nav {
    flex: 1 1 420px;
}

header nav ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    list-style-type: none;
    gap: 1rem;
    margin: 0;
    padding: 0;
}

nav li {
    padding: 0;
}

nav a {
    display: inline-block;
    padding: 0.4rem 0.75rem;
    border-radius: 0.4rem;
    font-size: 1.1rem;
    color: var(--text-secondary);
    text-decoration: none;
    transition: color 0.3s ease, background-color 0.3s ease, transform 0.3s ease;
}

nav a:hover {
    color: var(--accent-color);
    background-color: rgba(255, 255, 255, 0.06);    
    transform: translateY(-1px);
}

/* Main Content */

/* Shared Section Styles */

.colors, .fonts, .text-styles, .buttons {
    display: flex;
    flex-direction: column;
    padding: 1rem;
    border: 1px solid var(--border-card-color);
    border-radius: 0.5rem;
    background-color: var(--surface-section);
    margin-top: 2rem;
}

.colors h2, .fonts h2, .text-styles h2, .buttons h2 {
    margin: 1rem;
    color: var(--text-primary);
}

/* Color section */

.color-palette {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
    gap: 2rem;
    margin: 1.5rem 0;
}

.color-item {
    min-height: 170px;
    padding: 1rem;
    border: 1px solid var(--border-card-color);
    border-radius: 0.5rem;
    text-align: center;
    color: var(--text-primary);
}

.color-item h3 {
    margin-top: 0;
    margin-bottom: 1rem;
}

.color-item p {
    margin: 0.4rem 0;
}

.dark-navy {
    background-color: var(--color-palette1);
}

.crimson {
    background-color: var(--color-palette2);
}

.lime-cream {
    background-color: var(--color-palette3);
}

.pearl-aqua {
    background-color: var(--color-palette4);
    color: var(--text-dark);
}

.linen {
    background-color: var(--color-palette5);
    color: var(--text-dark);
}

.smoky-rose {
    background-color: var(--color-palette6);
}

.magenta {
    background-color: var(--color-palette7);
}

.orange-red {
    background-color: var(--color-palette8);
}

.yellow {
    background-color: var(--color-palette9);
    color: var(--text-dark);
}

.aquamarine {
    background-color: var(--color-palette10);
    color: var(--text-dark);
}

.spring-green {
    background-color: var(--color-palette11);
    color: var(--text-dark);
}

.salmon {
    background-color: var(--color-palette12);
}

/* Fonts section */

.font-samples {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 1.5rem 0;
}

.font-item {
    min-height: 170px;
    padding: 1rem;
    text-align: left;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--surface-card);
    border: 1px solid var(--border-card-color);
    border-radius: 0.5rem;
}

.font-item h3 {
    margin-top: 0;
    margin-bottom: 1rem;
    text-decoration: underline;
}

.author a {
    color: var(--text-muted);
    text-decoration: none;
    transition: color 0.3s ease;
}

.font-item a:hover {
    color: var(--accent-color); 
}

.inter, .inter a {
    font-family: 'Inter', sans-serif;
}

.poppins, .poppins a {
    font-family: 'Poppins', sans-serif;
}

.roboto, .roboto a {
    font-family: 'Roboto', sans-serif;
}

.montserrat, .montserrat a {
    font-family: 'Montserrat', sans-serif;
}

.merriweather, .merriweather a {
    font-family: 'Merriweather', serif;
}

.fira-code, .fira-code a {
    font-family: 'Fira Code', monospace;
}   

.playfair-display, .playfair-display a {
    font-family: 'Playfair Display', serif;
}

.source-code-pro, .source-code-pro a {
    font-family: 'Source Code Pro', monospace;
}

.nunito-sans, .nunito-sans a {
    font-family: 'Nunito Sans', sans-serif;
}

/* Text Styles */

.text-style {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 1.5rem 0;
}

.text-style-item {
    min-height: 170px;
    padding: 1rem;
    text-align: left;
    line-height: 1.5;
    color: var(--text-primary);
    background-color: var(--surface-card);
    border: 1px solid var(--border-card-color);
    border-radius: 0.5rem; 
}

.text-style-item ul {
    margin-bottom: 0;
    padding-left: 1.2rem;
}

.text-style-item li {
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

.heading1 h1, .heading2 h2, .heading3 h3, .paragraph p {
    margin-top: 0;
    margin-bottom: 1rem;
}

/* Buttons */

.button-samples {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
    margin: 2rem 0;
}

.classic-button, .flat-button, .skeuomorphism-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: min(100%, 220px);
    min-height: 56px;
    padding: 1rem 2rem;
    border-radius: 0.25rem;
    font-family: "Inter", serif;
    font-size: 1.125rem;
    font-weight: 500;
    letter-spacing: 0.03em;
    text-align: center;
    cursor: pointer;
    transition: background-color 0.3s ease, color 0.3s ease, transform 0.3s ease, box-shadow 0.3s ease;
}

/* Classic Button */

.classic-button {
    background-color: var(--accent-color);
    color: var(--text-dark);
    border: none;
}

.classic-button:hover {
    background-color: #0ea5e9;
    transform: translateY(-2px);
    box-shadow: 0 6px 14px rgba(0,0,0,0.3);
}

/* Flat Button */

.flat-button {
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-card-color);
}

.flat-button:hover {
    background-color: rgba(255,255,255,0.06);
    color: var(--accent-color);
    transform: translateY(-2px);
}

.flat-button span {
    position: relative;
    display: inline-block;
    transition: transform 0.3s;
}

.flat-button span:after {
    content: "\00bb";
    position: absolute;
    right: -1.25rem;
    opacity: 0;
    transition: opacity 0.3s ease, right 0.3s ease;
}

.flat-button:hover span {
  transform: translateX(-0.2rem);
}

.flat-button:hover span:after {
    right: -1rem;
    opacity: 1;
}

/* Skeuomorphism Button */

.skeuomorphism-button {
    background: linear-gradient(145deg, #f8fafc, #e2e8f0);
    color: var(--text-dark);
    border: 1px solid rgba(0,0,0,0.2);
    box-shadow:
        6px 6px 14px rgba(0,0,0,0.45),
        -3px -3px 8px rgba(255,255,255,0.7),
        inset 0 1px 2px rgba(255,255,255,0.8);
}

.skeuomorphism-button:hover {
    transform: translateY(-2px);
    box-shadow:
        8px 8px 18px rgba(0,0,0,0.5),
        -4px -4px 10px rgba(255,255,255,0.8),
        inset 0 1px 2px rgba(255,255,255,0.9);
}

.skeuomorphism-button:active {
    transform: translateY(1px);
    box-shadow:
        inset 4px 4px 8px rgba(0,0,0,0.4),
        inset -2px -2px 6px rgba(255,255,255,0.6);
}

/* Footer */

footer {
    width: 100%;
    height: 4rem;
    font-size: 1rem;
    text-align: right;
    border-top: solid 1px var(--border-card-color);
}

footer .content {
    padding: 1rem;
}

/* ============================= */
/* MOBILE (≤ 600px) */
/* ============================= */

@media (max-width: 600px) {

    header .main-title {
        text-align: center;
    }

    header nav ul {
        flex-direction: column;
        align-items: center;
        gap: 0.5em;
    }
  
    nav a {
        display: block;
        width: 100%;
        max-width: 220px;
        padding: 0.6rem;
        text-align: center;
    }

    .button-samples {
        flex-direction: column;
        align-items: center;
    }
    
    .classic-button, .flat-button, .skeuomorphism-button {
        width: 100%;
        max-width: 320px;
    }

    footer {
        text-align: center;
    }
}

/* ============================= */
/* VERY SMALL SCREENS (≤ 400px) */
/* ============================= */

@media (max-width: 400px) {

    nav a {
        padding: 0.5rem;
    }

    .color-palette, .font-samples, .text-style {
        gap: 0.75rem;
    }

    .button-samples {
        gap: 1rem;
    }

    .classic-button, .flat-button, .skeuomorphism-button {
        padding: 0.8rem 1rem;
        font-size: 1rem;
        white-space: normal;
    }

}

/* ============================= */
/* EXTRA SMALL (≤ 320px) */
/* ============================= */

@media (max-width: 320px) {
    
    /* grids stack */
    
    .color-palette, .font-samples, .text-style {
        grid-template-columns: 1fr;
    }

}