:root {
    --primary: #00d2ff;
    --background: #252830;
    --surface: #252830;
    --text: #e2e8f0;
    --text-muted: #94a3b8;
    --shadow-light: rgba(255, 255, 255, 0.05);
    --shadow-dark: rgba(0, 0, 0, 0.5);
    --shadow-glow: rgba(0, 210, 255, 0.3);
}

body {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    background: var(--background);
    color: var(--text);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    background: var(--surface);
    padding: 2.5rem 2rem;
    border-radius: 2rem;
    width: 90%;
    max-width: 480px;
    box-shadow: 12px 12px 24px var(--shadow-dark), -12px -12px 24px var(--shadow-light);
    transition: transform 0.3s ease;
}

h1 {
    text-align: center;
    margin-top: 0;
    margin-bottom: 2.5rem;
    font-size: 1.75rem;
    font-weight: 600;
    color: #fff;
    letter-spacing: -0.025em;
    text-shadow: 2px 2px 4px var(--shadow-dark), -2px -2px 4px var(--shadow-light);
}

.password-box {
    display: flex;
    background: var(--surface);
    border-radius: 1rem;
    overflow: hidden;
    margin-bottom: 2.5rem;
    box-shadow: inset 8px 8px 16px var(--shadow-dark), inset -8px -8px 16px var(--shadow-light);
}

#password {
    background: transparent;
    border: none;
    color: var(--primary);
    font-family: 'Consolas', monospace;
    font-size: 1.25rem;
    font-weight: 600;
    padding: 1.25rem 1.5rem;
    width: 100%;
    min-width: 0;
    outline: none;
    letter-spacing: 0.5px;
    text-overflow: ellipsis;
    text-shadow: 0 0 10px rgba(0, 210, 255, 0.2);
}

.buttons {
    display: flex;
    flex-shrink: 0;
    padding: 0.5rem;
}

.buttons button {
    background: var(--surface);
    border: none;
    border-radius: 0.75rem;
    color: var(--text);
    padding: 0.75rem;
    margin-left: 0.5rem;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 1.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 4px 4px 8px var(--shadow-dark), -4px -4px 8px var(--shadow-light);
}

.buttons button:active {
    box-shadow: inset 4px 4px 8px var(--shadow-dark), inset -4px -4px 8px var(--shadow-light);
    transform: translateY(2px);
}

.settings {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.setting {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 1rem;
    color: var(--text-muted);
}

.length-setting {
    flex-direction: column;
    align-items: stretch;
    margin-bottom: 1rem;
    gap: 1.25rem;
}

.length-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

#length-val {
    background: var(--surface);
    color: var(--primary);
    padding: 0.4rem 0.8rem;
    border-radius: 0.75rem;
    font-size: 0.875rem;
    font-weight: 700;
    box-shadow: inset 4px 4px 8px var(--shadow-dark), inset -4px -4px 8px var(--shadow-light);
}

/* Custom Range Input */
input[type=range] {
    -webkit-appearance: none;
    appearance: none;
    width: 100%;
    background: transparent;
}

input[type=range]:focus {
    outline: none;
}

input[type=range]::-webkit-slider-thumb {
    -webkit-appearance: none;
    height: 24px;
    width: 24px;
    border-radius: 50%;
    background: var(--surface);
    cursor: pointer;
    margin-top: -10px;
    box-shadow: 4px 4px 8px var(--shadow-dark), -4px -4px 8px var(--shadow-light), inset 0 0 0 4px var(--primary);
    transition: transform 0.1s;
}

input[type=range]::-webkit-slider-thumb:hover {
    box-shadow: 4px 4px 8px var(--shadow-dark), -4px -4px 8px var(--shadow-light), inset 0 0 0 6px var(--primary);
}

input[type=range]::-webkit-slider-runnable-track {
    width: 100%;
    height: 6px;
    cursor: pointer;
    background: var(--surface);
    border-radius: 3px;
    box-shadow: inset 2px 2px 4px var(--shadow-dark), inset -2px -2px 4px var(--shadow-light);
}

/* Firefox range */
input[type=range]::-moz-range-thumb {
    height: 24px;
    width: 24px;
    border-radius: 50%;
    background: var(--surface);
    cursor: pointer;
    border: none;
    box-shadow: 4px 4px 8px var(--shadow-dark), -4px -4px 8px var(--shadow-light), inset 0 0 0 4px var(--primary);
}

input[type=range]::-moz-range-track {
    width: 100%;
    height: 6px;
    cursor: pointer;
    background: var(--surface);
    border-radius: 3px;
    border: none;
    box-shadow: inset 2px 2px 4px var(--shadow-dark), inset -2px -2px 4px var(--shadow-light);
}

/* Custom Checkbox */
input[type="checkbox"] {
    appearance: none;
    background-color: var(--surface);
    margin: 0;
    font: inherit;
    color: currentColor;
    width: 1.5em;
    height: 1.5em;
    border: none;
    border-radius: 0.35em;
    display: grid;
    place-content: center;
    cursor: pointer;
    box-shadow: 4px 4px 8px var(--shadow-dark), -4px -4px 8px var(--shadow-light);
    transition: all 0.2s ease;
}

input[type="checkbox"]::before {
    content: "";
    width: 0.75em;
    height: 0.75em;
    transform: scale(0);
    transition: 120ms transform ease-in-out;
    box-shadow: inset 1em 1em var(--primary);
    transform-origin: center;
    clip-path: polygon(14% 44%, 0 65%, 50% 100%, 100% 16%, 80% 0%, 43% 62%);
    filter: drop-shadow(0 0 4px var(--shadow-glow));
}

input[type="checkbox"]:checked {
    box-shadow: inset 4px 4px 8px var(--shadow-dark), inset -4px -4px 8px var(--shadow-light);
}

input[type="checkbox"]:checked::before {
    transform: scale(1);
}

.privacy {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 2rem;
    margin-bottom: 0;
    line-height: 1.5;
    opacity: 0.7;
}

@media (max-width: 480px) {
    .container {
        padding: 2rem 1.5rem;
        border-radius: 1.5rem;
    }
    
    #password {
        font-size: 1.1rem;
        padding: 1rem;
    }
}